First commit

2024-12-13 23:26:02 +05:30
commit ce95aceed5
93 changed files with 2976 additions and 0 deletions
--- a/app/.gitignore
+++ b/app/.gitignore
@@ -0,0 +1 @@
+/build
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -0,0 +1,58 @@
+plugins {
+    alias(libs.plugins.android.application)
+    alias(libs.plugins.kotlin.android)
+}
+
+android {
+    namespace = "devs.org.calculator"
+    compileSdk = 35
+
+    defaultConfig {
+        applicationId = "devs.org.calculator"
+        minSdk = 26
+        targetSdk = 34
+        versionCode = 1
+        versionName = "1.0"
+
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    buildTypes {
+        release {
+            isMinifyEnabled = false
+            proguardFiles(
+                getDefaultProguardFile("proguard-android-optimize.txt"),
+                "proguard-rules.pro"
+            )
+        }
+    }
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_11
+        targetCompatibility = JavaVersion.VERSION_11
+    }
+    kotlinOptions {
+        jvmTarget = "11"
+    }
+    buildFeatures{
+        viewBinding = true
+    }
+}
+
+dependencies {
+
+    implementation(libs.androidx.core.ktx)
+    implementation(libs.androidx.appcompat)
+    implementation(libs.material)
+    implementation(libs.androidx.activity)
+    implementation(libs.androidx.constraintlayout)
+    testImplementation(libs.junit)
+    androidTestImplementation(libs.androidx.junit)
+    androidTestImplementation(libs.androidx.espresso.core)
+
+    //custom dependencies
+    implementation(libs.exp4j)
+    implementation("com.github.bumptech.glide:glide:4.16.0")
+    implementation("androidx.documentfile:documentfile:1.0.1")
+    implementation("com.github.chrisbanes:PhotoView:2.3.0")
+    implementation("androidx.viewpager:viewpager:1.0.0")
+}
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile
--- a/app/src/androidTest/java/devs/org/calculator/ExampleInstrumentedTest.kt
+++ b/app/src/androidTest/java/devs/org/calculator/ExampleInstrumentedTest.kt
@@ -0,0 +1,24 @@
+package devs.org.calculator
+
+import androidx.test.platform.app.InstrumentationRegistry
+import androidx.test.ext.junit.runners.AndroidJUnit4
+
+import org.junit.Test
+import org.junit.runner.RunWith
+
+import org.junit.Assert.*
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+@RunWith(AndroidJUnit4::class)
+class ExampleInstrumentedTest {
+    @Test
+    fun useAppContext() {
+        // Context of the app under test.
+        val appContext = InstrumentationRegistry.getInstrumentation().targetContext
+        assertEquals("devs.org.calculator", appContext.packageName)
+    }
+}
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -0,0 +1,65 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"
+        android:maxSdkVersion="32" />
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
+        android:maxSdkVersion="29" />
+    <uses-permission android:name="android.permission.READ_MEDIA_IMAGES"
+        tools:ignore="SelectedPhotoAccess" />
+    <uses-permission android:name="android.permission.READ_MEDIA_VIDEO"
+        tools:ignore="SelectedPhotoAccess" />
+    <uses-permission android:name="android.permission.READ_MEDIA_AUDIO" />
+    <uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE"
+        tools:ignore="ScopedStorage" />
+
+    <application
+        android:name=".CalculatorApp"
+        android:allowBackup="true"
+        android:dataExtractionRules="@xml/data_extraction_rules"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.Calculator"
+        tools:targetApi="31">
+        <activity
+            android:name=".activities.DocumentsActivity"
+            android:exported="false" />
+        <activity
+            android:name=".activities.AudioGalleryActivity"
+            android:exported="false" />
+        <activity
+            android:name=".activities.VideoGalleryActivity"
+            android:exported="false" />
+        <activity
+            android:name=".activities.ImageGalleryActivity"
+            android:exported="false" />
+        <activity
+            android:name=".activities.SetupPasswordActivity"
+            android:exported="false" />
+        <activity
+            android:name=".activities.SplashActivity"
+            android:exported="true"/>
+
+        <activity
+            android:name=".activities.MainActivity"
+            android:exported="true" >
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+        <activity
+            android:name=".activities.HiddenVaultActivity"
+            android:exported="true" />
+        <activity
+            android:name=".activities.PreviewActivity"
+            android:theme="@style/Theme.AppCompat.NoActionBar"
+            android:configChanges="orientation|screenSize"/>
+    </application>
+
+</manifest>
--- a/app/src/main/ic_launcher-playstore.png
+++ b/app/src/main/ic_launcher-playstore.png
--- a/app/src/main/java/devs/org/calculator/CalculatorApp.kt
+++ b/app/src/main/java/devs/org/calculator/CalculatorApp.kt
@@ -0,0 +1,12 @@
+package devs.org.calculator
+
+import android.app.Application
+import com.google.android.material.color.DynamicColors
+
+class CalculatorApp : Application() {
+    override fun onCreate() {
+        super.onCreate()
+        // Apply dynamic colors to enable Material You theming
+        DynamicColors.applyToActivitiesIfAvailable(this)
+    }
+} 
--- a/app/src/main/java/devs/org/calculator/activities/AudioGalleryActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/AudioGalleryActivity.kt
@@ -0,0 +1,60 @@
+package devs.org.calculator.activities
+
+import android.content.Intent
+import android.net.Uri
+import android.os.Bundle
+import android.widget.Toast
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.contract.ActivityResultContracts
+import devs.org.calculator.utils.FileManager
+import java.io.File
+
+class AudioGalleryActivity : BaseGalleryActivity() {
+    override val fileType = FileManager.FileType.AUDIO
+    private lateinit var pickAudioLauncher: ActivityResultLauncher<Intent>
+    private var selectedUri: Uri? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setupFabButton()
+
+        pickAudioLauncher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
+            if (result.resultCode == RESULT_OK) {
+                val uri = result.data?.data
+                if (uri != null) {
+                    selectedUri = uri
+                    try {
+                        val file = fileManager.copyFileToHiddenDir(selectedUri!!, fileType)
+                        if (file != null && file.exists()) {
+                            Toast.makeText(this, "File hidden successfully", Toast.LENGTH_SHORT).show()
+                            loadFiles()
+                        } else {
+                            Toast.makeText(this, "Failed to hide file", Toast.LENGTH_SHORT).show()
+                        }
+                    } catch (e: Exception) {
+                        Toast.makeText(this, "Error: ${e.message}", Toast.LENGTH_SHORT).show()
+                    }
+                } else {
+                    Toast.makeText(this, "No audio selected", Toast.LENGTH_SHORT).show()
+                }
+            }
+        }
+    }
+
+    private fun setupFabButton() {
+        binding.fabAdd.setOnClickListener {
+            val intent = Intent(Intent.ACTION_OPEN_DOCUMENT).apply {
+                type = "audio/*"
+                addCategory(Intent.CATEGORY_OPENABLE)
+                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION)
+            }
+            pickAudioLauncher.launch(intent)
+        }
+    }
+
+    override fun openPreview(file: File) {
+        // Implement audio preview
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/BaseGalleryActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/BaseGalleryActivity.kt
@@ -0,0 +1,100 @@
+package devs.org.calculator.activities
+
+import android.Manifest
+import android.content.Intent
+import android.content.pm.PackageManager
+import android.net.Uri
+import android.os.Build
+import android.os.Bundle
+import android.os.Environment
+import android.provider.Settings
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.IntentSenderRequest
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.appcompat.app.AppCompatActivity
+import androidx.recyclerview.widget.GridLayoutManager
+import devs.org.calculator.adapters.FileAdapter
+import devs.org.calculator.databinding.ActivityGalleryBinding
+import devs.org.calculator.utils.FileManager
+import java.io.File
+
+abstract class BaseGalleryActivity : AppCompatActivity() {
+    protected lateinit var binding: ActivityGalleryBinding
+    protected lateinit var fileManager: FileManager
+    protected lateinit var adapter: FileAdapter
+
+    private lateinit var intentSenderLauncher: ActivityResultLauncher<IntentSenderRequest>
+
+    abstract val fileType: FileManager.FileType
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setupIntentSenderLauncher()
+        checkPermissions()
+        binding = ActivityGalleryBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        fileManager = FileManager(this, this)
+        setupRecyclerView()
+        loadFiles()
+    }
+
+    private fun setupIntentSenderLauncher() {
+        intentSenderLauncher = registerForActivityResult(
+            ActivityResultContracts.StartIntentSenderForResult()
+        ) { result ->
+            if (result.resultCode == RESULT_OK) {
+                loadFiles() // Refresh the list after deletion
+            }
+        }
+    }
+
+    private fun setupRecyclerView() {
+        binding.recyclerView.layoutManager = GridLayoutManager(this, 3)
+        adapter = FileAdapter(
+            fileType
+        )
+        binding.recyclerView.adapter = adapter
+    }
+
+    protected fun loadFiles() {
+        val files = fileManager.getFilesInHiddenDir(fileType)
+        adapter.submitList(files)
+    }
+
+    abstract fun openPreview(file: File)
+
+    private fun checkPermissions() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
+            if (!Environment.isExternalStorageManager()) {
+                val intent = Intent(Settings.ACTION_MANAGE_APP_ALL_FILES_ACCESS_PERMISSION)
+                intent.addCategory("android.intent.category.DEFAULT")
+                intent.data = Uri.parse("package:${applicationContext.packageName}")
+                startActivityForResult(intent, 2296)
+            }
+        } else {
+            if (checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED ||
+                checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
+                requestPermissions(
+                    arrayOf(
+                        Manifest.permission.READ_EXTERNAL_STORAGE,
+                        Manifest.permission.WRITE_EXTERNAL_STORAGE
+                    ),
+                    1001
+                )
+            }
+        }
+    }
+
+    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
+        super.onActivityResult(requestCode, resultCode, data)
+        if (requestCode == 2296) {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
+                if (Environment.isExternalStorageManager()) {
+                    // Permission granted
+                    loadFiles()
+                }
+            }
+        }
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/DocumentsActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/DocumentsActivity.kt
@@ -0,0 +1,60 @@
+package devs.org.calculator.activities
+
+import android.content.Intent
+import android.net.Uri
+import android.os.Bundle
+import android.widget.Toast
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.contract.ActivityResultContracts
+import devs.org.calculator.utils.FileManager
+import java.io.File
+
+class DocumentsActivity : BaseGalleryActivity() {
+    override val fileType = FileManager.FileType.DOCUMENT
+    private lateinit var pickDocumentLauncher: ActivityResultLauncher<Intent>
+    private var selectedUri: Uri? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setupFabButton()
+
+        pickDocumentLauncher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
+            if (result.resultCode == RESULT_OK) {
+                val uri = result.data?.data
+                if (uri != null) {
+                    selectedUri = uri
+                    try {
+                        val file = fileManager.copyFileToHiddenDir(selectedUri!!, fileType)
+                        if (file != null && file.exists()) {
+                            Toast.makeText(this, "File hidden successfully", Toast.LENGTH_SHORT).show()
+                            loadFiles()
+                        } else {
+                            Toast.makeText(this, "Failed to hide file", Toast.LENGTH_SHORT).show()
+                        }
+                    } catch (e: Exception) {
+                        Toast.makeText(this, "Error: ${e.message}", Toast.LENGTH_SHORT).show()
+                    }
+                } else {
+                    Toast.makeText(this, "No document selected", Toast.LENGTH_SHORT).show()
+                }
+            }
+        }
+    }
+
+    private fun setupFabButton() {
+        binding.fabAdd.setOnClickListener {
+            val intent = Intent(Intent.ACTION_OPEN_DOCUMENT).apply {
+                type = "*/*"
+                addCategory(Intent.CATEGORY_OPENABLE)
+                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION)
+            }
+            pickDocumentLauncher.launch(intent)
+        }
+    }
+
+    override fun openPreview(file: File) {
+        // Implement document preview
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/HiddenVaultActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/HiddenVaultActivity.kt
@@ -0,0 +1,36 @@
+package devs.org.calculator.activities
+
+import android.content.Intent
+import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import devs.org.calculator.databinding.ActivityHiddenVaultBinding
+import devs.org.calculator.utils.FileManager
+
+class HiddenVaultActivity : AppCompatActivity() {
+    private lateinit var binding: ActivityHiddenVaultBinding
+    private lateinit var fileManager: FileManager
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        binding = ActivityHiddenVaultBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        fileManager = FileManager(this, this)
+        setupNavigation()
+    }
+
+    private fun setupNavigation() {
+        binding.btnImages.setOnClickListener {
+            startActivity(Intent(this, ImageGalleryActivity::class.java))
+        }
+        binding.btnVideos.setOnClickListener {
+            startActivity(Intent(this, VideoGalleryActivity::class.java))
+        }
+        binding.btnAudio.setOnClickListener {
+            startActivity(Intent(this, AudioGalleryActivity::class.java))
+        }
+        binding.btnDocs.setOnClickListener {
+            startActivity(Intent(this, DocumentsActivity::class.java))
+        }
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/ImageGalleryActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/ImageGalleryActivity.kt
@@ -0,0 +1,166 @@
+package devs.org.calculator.activities
+
+import android.app.RecoverableSecurityException
+import android.content.Context
+import android.content.Intent
+import android.net.Uri
+import android.os.Build
+import android.os.Bundle
+import android.os.Environment
+import android.provider.MediaStore
+import android.provider.Settings
+import android.widget.Toast
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.IntentSenderRequest
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.documentfile.provider.DocumentFile
+import androidx.lifecycle.lifecycleScope
+import devs.org.calculator.utils.FileManager
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import java.io.File
+
+class ImageGalleryActivity : BaseGalleryActivity() {
+    override val fileType = FileManager.FileType.IMAGE
+
+    private lateinit var intentSenderLauncher: ActivityResultLauncher<IntentSenderRequest>
+    private var selectedImageUri: Uri? = null
+    private lateinit var pickImageLauncher: ActivityResultLauncher<Intent>
+
+    private suspend fun deletePhotoFromExternalStorage(photoUri: Uri) {
+        withContext(Dispatchers.IO) {
+            try {
+                // First try to delete using DocumentFile
+                val documentFile = DocumentFile.fromSingleUri(this@ImageGalleryActivity, photoUri)
+                if (documentFile?.exists() == true && documentFile.canWrite()) {
+                    val deleted = documentFile.delete()
+                    withContext(Dispatchers.Main) {
+                        if (deleted) {
+                            Toast.makeText(this@ImageGalleryActivity, "File deleted successfully", Toast.LENGTH_SHORT).show()
+                            selectedImageUri = null
+                        } else {
+                            Toast.makeText(this@ImageGalleryActivity, "Failed to delete file", Toast.LENGTH_SHORT).show()
+                        }
+                    }
+                    return@withContext
+                }
+
+                // If DocumentFile approach fails, try content resolver
+                try {
+                    contentResolver.delete(photoUri, null, null)
+                    withContext(Dispatchers.Main) {
+                        Toast.makeText(this@ImageGalleryActivity, "File deleted successfully", Toast.LENGTH_SHORT).show()
+                    }
+                } catch (e: SecurityException) {
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+                        val intentSender = when {
+                            Build.VERSION.SDK_INT >= Build.VERSION_CODES.R -> {
+                                MediaStore.createDeleteRequest(contentResolver, listOf(photoUri)).intentSender
+                            }
+                            else -> {
+                                val recoverableSecurityException = e as? RecoverableSecurityException
+                                recoverableSecurityException?.userAction?.actionIntent?.intentSender
+                            }
+                        }
+                        intentSender?.let { sender ->
+                            withContext(Dispatchers.Main) {
+                                intentSenderLauncher.launch(
+                                    IntentSenderRequest.Builder(sender).build()
+                                )
+                            }
+                        }
+                    }
+                }
+            } catch (e: Exception) {
+                withContext(Dispatchers.Main) {
+                    Toast.makeText(
+                        this@ImageGalleryActivity,
+                        "Error deleting file: ${e.message}",
+                        Toast.LENGTH_LONG
+                    ).show()
+                }
+            }
+        }
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setupIntentSenderLauncher()
+        setupFabButton()
+
+        intentSenderLauncher = registerForActivityResult(ActivityResultContracts.StartIntentSenderForResult()){
+            if (it.resultCode == RESULT_OK){
+                Toast.makeText(this, "Photo Deleted Successfully", Toast.LENGTH_SHORT).show()
+            }else{
+                Toast.makeText(this, "Failed to delete photo", Toast.LENGTH_SHORT).show()
+            }
+        }
+
+        pickImageLauncher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
+            if (result.resultCode == RESULT_OK) {
+                val uri = result.data?.data
+                if (uri != null) {
+                    selectedImageUri = uri
+                    try {
+                        val file = fileManager.copyFileToHiddenDir(selectedImageUri!!, fileType)
+                        if (file != null && file.exists()) {
+                            Toast.makeText(this, "File hidden successfully", Toast.LENGTH_SHORT).show()
+                            loadFiles()
+                        } else {
+                            Toast.makeText(this, "Failed to hide file", Toast.LENGTH_SHORT).show()
+                        }
+                    } catch (e: Exception) {
+                        Toast.makeText(this, "Error: ${e.message}", Toast.LENGTH_SHORT).show()
+                    }
+                } else {
+                    Toast.makeText(this, "No image selected", Toast.LENGTH_SHORT).show()
+                }
+            }
+        }
+        askPermissiom()
+    }
+
+    private fun setupIntentSenderLauncher() {
+        intentSenderLauncher = registerForActivityResult(
+            ActivityResultContracts.StartIntentSenderForResult()
+        ) { result ->
+            if (result.resultCode == RESULT_OK) {
+                loadFiles()
+            }
+        }
+    }
+
+    private fun askPermissiom() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R){
+            if (!Environment.isExternalStorageManager()){
+                val intent = Intent().setAction(Settings.ACTION_MANAGE_ALL_FILES_ACCESS_PERMISSION)
+                startActivity(intent)
+            }
+        }
+        else {
+            Toast.makeText(this, "Android Version Lower", Toast.LENGTH_SHORT).show()
+        }
+    }
+
+    private fun setupFabButton() {
+        binding.fabAdd.setOnClickListener {
+            val intent = Intent(Intent.ACTION_OPEN_DOCUMENT).apply {
+                type = "image/*"
+                addCategory(Intent.CATEGORY_OPENABLE)
+                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION)
+            }
+            pickImageLauncher.launch(intent)
+        }
+    }
+
+    override fun openPreview(file: File) {
+        val intent = Intent(this, PreviewActivity::class.java).apply {
+            putExtra(PreviewActivity.EXTRA_FILE_PATH, file.absolutePath)
+            putExtra(PreviewActivity.EXTRA_FILE_TYPE, fileType.name)
+        }
+        startActivity(intent)
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/MainActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/MainActivity.kt
@@ -0,0 +1,172 @@
+package devs.org.calculator.activities
+
+import android.app.Activity
+import android.content.Context
+import android.content.Intent
+import android.net.Uri
+import android.os.Bundle
+import android.util.Log
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.appcompat.app.AppCompatActivity
+import com.google.android.material.button.MaterialButton
+import devs.org.calculator.databinding.ActivityMainBinding
+import devs.org.calculator.utils.PrefsUtil
+import net.objecthunter.exp4j.ExpressionBuilder
+
+class MainActivity : AppCompatActivity() {
+    private lateinit var binding: ActivityMainBinding
+    private var currentExpression = "0"
+    private var lastWasOperator = false
+    private var hasDecimal = false
+    private lateinit var launcher: ActivityResultLauncher<Intent>
+    private lateinit var baseDocumentTreeUri: Uri
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        binding = ActivityMainBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        // Initialize ActivityResultLauncher
+        launcher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
+            handleActivityResult(result)
+        }
+
+        // Ask for base directory picker on startup
+
+        // Number buttons
+        setupNumberButton(binding.btn0, "0")
+        setupNumberButton(binding.btn1, "1")
+        setupNumberButton(binding.btn2, "2")
+        setupNumberButton(binding.btn3, "3")
+        setupNumberButton(binding.btn4, "4")
+        setupNumberButton(binding.btn5, "5")
+        setupNumberButton(binding.btn6, "6")
+        setupNumberButton(binding.btn7, "7")
+        setupNumberButton(binding.btn8, "8")
+        setupNumberButton(binding.btn9, "9")
+
+        // Operator buttons
+        setupOperatorButton(binding.btnPlus, "+")
+        setupOperatorButton(binding.btnMinus, "-")
+        setupOperatorButton(binding.btnMultiply, "*")
+        setupOperatorButton(binding.btnDivide, "/")
+
+        // Special buttons
+        binding.btnClear.setOnClickListener { clearDisplay() }
+        binding.btnDot.setOnClickListener { addDecimal() }
+        binding.btnEquals.setOnClickListener { calculateResult() }
+        binding.btnPercent.setOnClickListener { calculatePercentage() }
+    }
+
+    private fun launchBaseDirectoryPicker() {
+        val intent = Intent(Intent.ACTION_OPEN_DOCUMENT_TREE)
+        launcher.launch(intent)
+    }
+
+    private fun handleActivityResult(result: androidx.activity.result.ActivityResult) {
+        if (result.resultCode == Activity.RESULT_OK) {
+            result.data?.data?.let { uri ->
+                baseDocumentTreeUri = uri
+                val takeFlags = Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION
+
+                // Take persistable Uri Permission for future use
+                contentResolver.takePersistableUriPermission(uri, takeFlags)
+
+                val preferences = getSharedPreferences("com.example.fileutility", Context.MODE_PRIVATE)
+                preferences.edit().putString("filestorageuri", uri.toString()).apply()
+            }
+        } else {
+            Log.e("FileUtility", "Error occurred or operation cancelled: $result")
+        }
+    }
+
+    private fun setupNumberButton(button: MaterialButton, number: String) {
+        button.setOnClickListener {
+            if (currentExpression == "0") {
+                currentExpression = number
+            } else {
+                currentExpression += number
+            }
+            lastWasOperator = false
+            updateDisplay()
+        }
+    }
+
+    private fun setupOperatorButton(button: MaterialButton, operator: String) {
+        button.setOnClickListener {
+            if (!lastWasOperator) {
+                currentExpression += operator
+                lastWasOperator = true
+                hasDecimal = false
+            }
+            updateDisplay()
+        }
+    }
+
+    private fun clearDisplay() {
+        currentExpression = "0"
+        lastWasOperator = false
+        hasDecimal = false
+        updateDisplay()
+    }
+
+    private fun addDecimal() {
+        if (!hasDecimal && !lastWasOperator) {
+            currentExpression += "."
+            hasDecimal = true
+            updateDisplay()
+        }
+    }
+
+    private fun calculatePercentage() {
+        try {
+            val value = currentExpression.toDouble()
+            currentExpression = (value / 100).toString()
+            updateDisplay()
+        } catch (e: Exception) {
+            binding.display.text = "Error"
+        }
+    }
+
+    private fun calculateResult() {
+        // Check for secret code
+        if (currentExpression == "123456") { // Replace with your desired code
+            val intent = Intent(this, SetupPasswordActivity::class.java)
+            intent.putExtra("password", currentExpression)
+            startActivity(intent)
+            clearDisplay()
+            return
+        }
+
+        // Validate password
+        if (PrefsUtil(this).validatePassword(currentExpression)) {
+            val intent = Intent(this, HiddenVaultActivity::class.java)
+            intent.putExtra("password", currentExpression)
+            startActivity(intent)
+            clearDisplay()
+            return
+        }
+
+        try {
+            val expression = ExpressionBuilder(currentExpression).build()
+            val result = expression.evaluate()
+
+            currentExpression = if (result.toLong().toDouble() == result) {
+                result.toLong().toString()
+            } else {
+                String.format("%.2f", result)
+            }
+
+            lastWasOperator = false
+            hasDecimal = currentExpression.contains(".")
+            updateDisplay()
+        } catch (e: Exception) {
+            binding.display.text = "Error"
+        }
+    }
+
+    private fun updateDisplay() {
+        binding.display.text = currentExpression
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/PreviewActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/PreviewActivity.kt
@@ -0,0 +1,51 @@
+package devs.org.calculator.activities
+
+import ImagePreviewAdapter
+import android.os.Bundle
+import android.view.View
+import android.widget.MediaController
+import androidx.appcompat.app.AppCompatActivity
+import com.bumptech.glide.Glide
+import devs.org.calculator.databinding.ActivityPreviewBinding
+import devs.org.calculator.utils.FileManager
+import java.io.File
+
+class PreviewActivity : AppCompatActivity() {
+
+    companion object {
+        const val EXTRA_FILE_PATH = "file_path"
+        const val EXTRA_FILE_TYPE = "file_type"
+    }
+
+    private lateinit var binding: ActivityPreviewBinding
+    private var currentPosition: Int = 0
+    private lateinit var files: List<File>
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        binding = ActivityPreviewBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+
+        setSupportActionBar(binding.toolbar)
+        supportActionBar?.setDisplayHomeAsUpEnabled(true)
+        supportActionBar?.title = ""
+
+        currentPosition = intent.getIntExtra("position", 0)
+        val filePath = intent.getStringExtra("file_path") ?: return
+        val file = File(filePath)
+        files = file.parentFile?.listFiles()?.toList() ?: listOf(file)
+
+        setupImagePreview()
+    }
+
+    private fun setupImagePreview() {
+        val adapter = ImagePreviewAdapter(this, files)
+        binding.viewPager.adapter = adapter
+        binding.viewPager.currentItem = currentPosition
+    }
+
+    override fun onSupportNavigateUp(): Boolean {
+        onBackPressed()
+        return true
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/SetupPasswordActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/SetupPasswordActivity.kt
@@ -0,0 +1,37 @@
+package devs.org.calculator.activities
+
+import android.content.Intent
+import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import devs.org.calculator.databinding.ActivitySetupPasswordBinding
+import devs.org.calculator.utils.PrefsUtil
+
+class SetupPasswordActivity : AppCompatActivity() {
+    private lateinit var binding: ActivitySetupPasswordBinding
+    private lateinit var prefsUtil: PrefsUtil
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        binding = ActivitySetupPasswordBinding.inflate(layoutInflater)
+        setContentView(binding.root)
+        prefsUtil = PrefsUtil(this)
+
+        binding.btnSavePassword.setOnClickListener {
+            val password = binding.etPassword.text.toString()
+            val confirmPassword = binding.etConfirmPassword.text.toString()
+
+            if (password == confirmPassword && password.isNotEmpty()) {
+                prefsUtil.savePassword(password)
+                startActivity(Intent(this, MainActivity::class.java))
+                finish()
+            } else {
+                binding.etPassword.error = "Passwords don't match"
+            }
+        }
+
+        binding.btnResetPassword.setOnClickListener {
+            // Implement password reset logic
+            // Could use security questions or email verification
+        }
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/SplashActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/SplashActivity.kt
@@ -0,0 +1,32 @@
+package devs.org.calculator.activities
+
+import android.annotation.SuppressLint
+import android.content.Intent
+import android.os.Bundle
+import android.os.Handler
+import android.os.Looper
+import androidx.activity.enableEdgeToEdge
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.view.ViewCompat
+import androidx.core.view.WindowInsetsCompat
+import devs.org.calculator.R
+
+@SuppressLint("CustomSplashScreen")
+class SplashActivity : AppCompatActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        enableEdgeToEdge()
+        setContentView(R.layout.activity_splash)
+        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main)) { v, insets ->
+            val systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars())
+            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom)
+            insets
+        }
+        //code starts from here
+        val handler = Handler(Looper.getMainLooper())
+            .postDelayed({
+                startActivity(Intent(this, MainActivity::class.java))
+                finish()
+            },2000)
+    }
+}
--- a/app/src/main/java/devs/org/calculator/activities/VideoGalleryActivity.kt
+++ b/app/src/main/java/devs/org/calculator/activities/VideoGalleryActivity.kt
@@ -0,0 +1,65 @@
+package devs.org.calculator.activities
+
+import android.content.Intent
+import android.net.Uri
+import android.os.Bundle
+import android.widget.Toast
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.contract.ActivityResultContracts
+import devs.org.calculator.utils.FileManager
+import java.io.File
+
+class VideoGalleryActivity : BaseGalleryActivity() {
+    override val fileType = FileManager.FileType.VIDEO
+    private lateinit var pickVideoLauncher: ActivityResultLauncher<Intent>
+    private var selectedUri: Uri? = null
+
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setupFabButton()
+
+        pickVideoLauncher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
+            if (result.resultCode == RESULT_OK) {
+                val uri = result.data?.data
+                if (uri != null) {
+                    selectedUri = uri
+                    try {
+                        val file = fileManager.copyFileToHiddenDir(selectedUri!!, fileType)
+                        if (file != null && file.exists()) {
+                            Toast.makeText(this, "File hidden successfully", Toast.LENGTH_SHORT).show()
+                            loadFiles()
+                        } else {
+                            Toast.makeText(this, "Failed to hide file", Toast.LENGTH_SHORT).show()
+                        }
+                    } catch (e: Exception) {
+                        Toast.makeText(this, "Error: ${e.message}", Toast.LENGTH_SHORT).show()
+                    }
+                } else {
+                    Toast.makeText(this, "No video selected", Toast.LENGTH_SHORT).show()
+                }
+            }
+        }
+    }
+
+    private fun setupFabButton() {
+        binding.fabAdd.setOnClickListener {
+            val intent = Intent(Intent.ACTION_OPEN_DOCUMENT).apply {
+                type = "video/*"
+                addCategory(Intent.CATEGORY_OPENABLE)
+                addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
+                addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION)
+            }
+            pickVideoLauncher.launch(intent)
+        }
+    }
+
+    override fun openPreview(file: File) {
+        val intent = Intent(this, PreviewActivity::class.java).apply {
+            putExtra(PreviewActivity.EXTRA_FILE_PATH, file.absolutePath)
+            putExtra(PreviewActivity.EXTRA_FILE_TYPE, fileType.name)
+        }
+        startActivity(intent)
+    }
+}
--- a/app/src/main/java/devs/org/calculator/adapters/FileAdapter.kt
+++ b/app/src/main/java/devs/org/calculator/adapters/FileAdapter.kt
@@ -0,0 +1,73 @@
+package devs.org.calculator.adapters
+
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.ImageView
+import androidx.recyclerview.widget.DiffUtil
+import androidx.recyclerview.widget.ListAdapter
+import androidx.recyclerview.widget.RecyclerView
+import com.bumptech.glide.Glide
+import devs.org.calculator.R
+import devs.org.calculator.utils.FileManager
+import java.io.File
+
+class FileAdapter(private val fileType: FileManager.FileType) :
+    ListAdapter<File, FileAdapter.FileViewHolder>(FileDiffCallback()) {
+
+    private val selectedItems = mutableSetOf<Int>()
+    private var isSelectionMode = false
+
+    inner class FileViewHolder(view: View) : RecyclerView.ViewHolder(view) {
+        private val imageView: ImageView = view.findViewById(R.id.imageView)
+
+        fun bind(file: File) {
+            when (fileType) {
+                FileManager.FileType.IMAGE -> {
+                    Glide.with(imageView)
+                        .load(file)
+                        .centerCrop()
+                        .into(imageView)
+                }
+                FileManager.FileType.VIDEO -> {
+                    Glide.with(imageView)
+                        .asBitmap()
+                        .load(file)
+                        .centerCrop()
+                        .into(imageView)
+                }
+                else -> {
+                    val resourceId = when (fileType) {
+                        FileManager.FileType.AUDIO -> R.drawable.ic_audio
+                        FileManager.FileType.DOCUMENT -> R.drawable.ic_document
+                        else -> R.drawable.ic_file
+                    }
+                    imageView.setImageResource(resourceId)
+                }
+            }
+            itemView.setOnClickListener { }
+        }
+    }
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): FileViewHolder {
+        val view = LayoutInflater.from(parent.context)
+            .inflate(R.layout.item_file, parent, false)
+        return FileViewHolder(view)
+    }
+
+    override fun onBindViewHolder(holder: FileViewHolder, position: Int) {
+        holder.bind(getItem(position))
+    }
+
+    class FileDiffCallback : DiffUtil.ItemCallback<File>() {
+        override fun areItemsTheSame(oldItem: File, newItem: File): Boolean {
+            // Compare based on file path or another unique identifier
+            return oldItem.path == newItem.path
+        }
+
+        override fun areContentsTheSame(oldItem: File, newItem: File): Boolean {
+            // Compare the content of files if needed
+            return oldItem == newItem
+        }
+    }
+}
--- a/app/src/main/java/devs/org/calculator/adapters/ImagePreviewAdapter.kt
+++ b/app/src/main/java/devs/org/calculator/adapters/ImagePreviewAdapter.kt
@@ -0,0 +1,36 @@
+import android.content.Context
+import android.view.View
+import android.view.ViewGroup
+import androidx.viewpager.widget.PagerAdapter
+import com.bumptech.glide.Glide
+import com.github.chrisbanes.photoview.PhotoView
+import java.io.File
+
+class ImagePreviewAdapter(
+    private val context: Context,
+    private val images: List<File>
+) : PagerAdapter() {
+
+    override fun instantiateItem(container: ViewGroup, position: Int): Any {
+        val photoView = PhotoView(context)
+        photoView.layoutParams = ViewGroup.LayoutParams(
+            ViewGroup.LayoutParams.MATCH_PARENT,
+            ViewGroup.LayoutParams.MATCH_PARENT
+        )
+
+        Glide.with(context)
+            .load(images[position])
+            .into(photoView)
+
+        container.addView(photoView)
+        return photoView
+    }
+
+    override fun destroyItem(container: ViewGroup, position: Int, obj: Any) {
+        container.removeView(obj as View)
+    }
+
+    override fun getCount(): Int = images.size
+
+    override fun isViewFromObject(view: View, obj: Any): Boolean = view === obj
+} 
--- a/app/src/main/java/devs/org/calculator/utils/FileManager.kt
+++ b/app/src/main/java/devs/org/calculator/utils/FileManager.kt
@@ -0,0 +1,195 @@
+package devs.org.calculator.utils
+
+import android.app.RecoverableSecurityException
+import android.content.Context
+import android.content.Intent
+import android.net.Uri
+import android.os.Build
+import android.os.Environment
+import android.provider.DocumentsContract
+import android.provider.MediaStore
+import android.webkit.MimeTypeMap
+import android.widget.Toast
+import androidx.activity.result.ActivityResultLauncher
+import androidx.activity.result.IntentSenderRequest
+import androidx.documentfile.provider.DocumentFile
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.lifecycleScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import java.io.File
+
+class FileManager(private val context: Context, private val lifecycleOwner: LifecycleOwner) {
+    private lateinit var intentSenderLauncher: ActivityResultLauncher<IntentSenderRequest>
+
+    companion object {
+        const val HIDDEN_DIR = ".CalculatorHide"
+        const val IMAGES_DIR = "images"
+        const val VIDEOS_DIR = "videos"
+        const val AUDIO_DIR = "audio"
+        const val DOCS_DIR = "documents"
+    }
+
+    fun getHiddenDirectory(): File {
+        val dir = File(Environment.getExternalStorageDirectory(), HIDDEN_DIR)
+        if (!dir.exists()) {
+            dir.mkdirs()
+            // Create .nomedia file to hide from media scanners
+            File(dir, ".nomedia").createNewFile()
+        }
+        return dir
+    }
+
+
+
+    fun getFilesInHiddenDir(type: FileType): List<File> {
+        val hiddenDir = getHiddenDirectory()
+        val typeDir = File(hiddenDir, type.dirName)
+        return if (typeDir.exists()) {
+            typeDir.listFiles()?.filterNotNull()?.filter { it.name != ".nomedia" } ?: emptyList()
+        } else {
+            emptyList()
+        }
+    }
+
+    fun hideFile(uri: Uri, type: FileType): File {
+        val inputStream = context.contentResolver.openInputStream(uri)
+        val targetDir = File(getHiddenDirectory(), type.dirName)
+        targetDir.mkdirs()
+
+        val fileName = "${System.currentTimeMillis()}_${uri.lastPathSegment}"
+        val targetFile = File(targetDir, fileName)
+
+        inputStream?.use { input ->
+            targetFile.outputStream().use { output ->
+                input.copyTo(output)
+            }
+        }
+
+        return targetFile
+    }
+
+    fun copyFileToHiddenDir(uri: Uri, type: FileType): File? {
+        return try {
+            val contentResolver = context.contentResolver
+
+            // Get the target directory
+            val targetDir = File(Environment.getExternalStorageDirectory(), "$HIDDEN_DIR/${type.dirName}")
+            targetDir.mkdirs()
+            File(targetDir, ".nomedia").createNewFile()
+
+            // Create target file
+            val mimeType = contentResolver.getType(uri)
+            val extension = MimeTypeMap.getSingleton()
+                .getExtensionFromMimeType(mimeType) ?: ""
+            val fileName = "${System.currentTimeMillis()}.${extension}"
+            val targetFile = File(targetDir, fileName)
+
+            // Copy file using DocumentFile
+            contentResolver.openInputStream(uri)?.use { input ->
+                targetFile.outputStream().use { output ->
+                    input.copyTo(output)
+                }
+            }
+
+            // Verify copy success
+            if (!targetFile.exists() || targetFile.length() == 0L) {
+                throw Exception("File copy failed")
+            }
+
+            // Media scan the new file to hide it
+            val mediaScanIntent = Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE)
+            mediaScanIntent.data = Uri.fromFile(targetDir)
+            context.sendBroadcast(mediaScanIntent)
+            lifecycleOwner.lifecycleScope.launch {
+                deletePhotoFromExternalStorage(uri)
+            }
+            targetFile
+        } catch (e: Exception) {
+            e.printStackTrace()
+            null
+        }
+    }
+
+    private suspend fun deletePhotoFromExternalStorage(photoUri: Uri) {
+        withContext(Dispatchers.IO) {
+            try {
+                // First try to delete using DocumentFile
+                val documentFile = DocumentFile.fromSingleUri(context, photoUri)
+                if (documentFile?.exists() == true && documentFile.canWrite()) {
+                    val deleted = documentFile.delete()
+                    withContext(Dispatchers.Main) {
+                        if (deleted) {
+                            Toast.makeText(context, "File deleted successfully", Toast.LENGTH_SHORT).show()
+                        } else {
+                            Toast.makeText(context, "Failed to delete file", Toast.LENGTH_SHORT).show()
+                        }
+                    }
+                    return@withContext
+                }
+
+                // If DocumentFile approach fails, try content resolver
+                try {
+                    context.contentResolver.delete(photoUri, null, null)
+                    withContext(Dispatchers.Main) {
+                        Toast.makeText(context, "File deleted successfully", Toast.LENGTH_SHORT).show()
+                    }
+                } catch (e: SecurityException) {
+                    // Handle security exception for Android 10 and above
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+                        val intentSender = when {
+                            Build.VERSION.SDK_INT >= Build.VERSION_CODES.R -> {
+                                MediaStore.createDeleteRequest(context.contentResolver, listOf(photoUri)).intentSender
+                            }
+                            else -> {
+                                val recoverableSecurityException = e as? RecoverableSecurityException
+                                recoverableSecurityException?.userAction?.actionIntent?.intentSender
+                            }
+                        }
+                        intentSender?.let { sender ->
+                            intentSenderLauncher.launch(
+                                IntentSenderRequest.Builder(sender).build()
+                            )
+                        }
+                    }
+                }
+            } catch (e: Exception) {
+                withContext(Dispatchers.Main) {
+                    Toast.makeText(
+                        context,
+                        "Error deleting file: ${e.message}",
+                        Toast.LENGTH_LONG
+                    ).show()
+                }
+            }
+        }
+    }
+
+    private fun deleteOriginalFile(uri: Uri) {
+        try {
+            val contentResolver = context.contentResolver
+            when {
+                DocumentsContract.isDocumentUri(context, uri) -> {
+                    DocumentsContract.deleteDocument(contentResolver, uri)
+                }
+                isMediaStoreUri(uri) -> {
+                    contentResolver.delete(uri, null, null)
+                }
+            }
+        } catch (e: Exception) {
+            e.printStackTrace()
+        }
+    }
+
+    private fun isMediaStoreUri(uri: Uri): Boolean {
+        return uri.authority?.startsWith("com.android.providers.media") == true
+    }
+
+    enum class FileType(val dirName: String) {
+        IMAGE(IMAGES_DIR),
+        VIDEO(VIDEOS_DIR),
+        AUDIO(AUDIO_DIR),
+        DOCUMENT(DOCS_DIR)
+    }
+}
--- a/app/src/main/java/devs/org/calculator/utils/PrefsUtil.kt
+++ b/app/src/main/java/devs/org/calculator/utils/PrefsUtil.kt
@@ -0,0 +1,46 @@
+package devs.org.calculator.utils
+
+import android.content.Context
+import android.content.SharedPreferences
+import java.security.MessageDigest
+
+class PrefsUtil(context: Context) {
+    private val prefs: SharedPreferences = context.getSharedPreferences("Calculator", Context.MODE_PRIVATE)
+
+    fun hasPassword(): Boolean {
+        return prefs.getString("password", "")?.isNotEmpty() ?: false
+    }
+
+    fun savePassword(password: String) {
+        val hashedPassword = hashPassword(password)
+        prefs.edit()
+            .putString("password", hashedPassword)
+            .apply()
+    }
+
+    fun validatePassword(input: String): Boolean {
+        val stored = prefs.getString("password", "") ?: ""
+        return stored == hashPassword(input)
+    }
+
+    fun saveSecurityQA(question: String, answer: String) {
+        prefs.edit()
+            .putString("security_question", question)
+            .putString("security_answer", hashPassword(answer))
+            .apply()
+    }
+
+    fun validateSecurityAnswer(answer: String): Boolean {
+        val stored = prefs.getString("security_answer", "") ?: ""
+        return stored == hashPassword(answer)
+    }
+
+    fun getSecurityQuestion(): String? {
+        return prefs.getString("security_question", null)
+    }
+
+    private fun hashPassword(password: String): String {
+        val bytes = MessageDigest.getInstance("SHA-256").digest(password.toByteArray())
+        return bytes.joinToString("") { "%02x".format(it) }
+    }
+}
--- a/app/src/main/java/devs/org/calculator/utils/SecurityUtils.kt
+++ b/app/src/main/java/devs/org/calculator/utils/SecurityUtils.kt
@@ -0,0 +1,64 @@
+package devs.org.calculator.utils
+
+import android.content.Context
+import android.net.Uri
+import java.io.File
+import java.io.FileInputStream
+import java.io.FileOutputStream
+import javax.crypto.Cipher
+import javax.crypto.SecretKey
+import javax.crypto.spec.SecretKeySpec
+
+class SecurityUtils {
+    companion object {
+        private const val ALGORITHM = "AES"
+        private const val HIDDEN_FOLDER = "Calculator_Data"
+        
+        fun validatePassword(input: String, storedHash: String): Boolean {
+            return input.hashCode().toString() == storedHash
+        }
+
+        fun encryptFile(context: Context, sourceUri: Uri, password: String): File {
+            val inputStream = context.contentResolver.openInputStream(sourceUri)
+            val secretKey = generateKey(password)
+            val cipher = Cipher.getInstance(ALGORITHM)
+            cipher.init(Cipher.ENCRYPT_MODE, secretKey)
+
+            val hiddenDir = File(context.getExternalFilesDir(null), HIDDEN_FOLDER)
+            if (!hiddenDir.exists()) hiddenDir.mkdirs()
+
+            val encryptedFile = File(hiddenDir, "${System.currentTimeMillis()}_encrypted")
+            val outputStream = FileOutputStream(encryptedFile)
+
+            inputStream?.use { input ->
+                val buffer = ByteArray(1024)
+                var read: Int
+                while (input.read(buffer).also { read = it } != -1) {
+                    val encrypted = cipher.update(buffer, 0, read)
+                    outputStream.write(encrypted)
+                }
+                val finalBlock = cipher.doFinal()
+                outputStream.write(finalBlock)
+            }
+            outputStream.close()
+            return encryptedFile
+        }
+
+        fun decryptFile(file: File, password: String): ByteArray {
+            val secretKey = generateKey(password)
+            val cipher = Cipher.getInstance(ALGORITHM)
+            cipher.init(Cipher.DECRYPT_MODE, secretKey)
+
+            val inputStream = FileInputStream(file)
+            val bytes = inputStream.readBytes()
+            inputStream.close()
+
+            return cipher.doFinal(bytes)
+        }
+
+        private fun generateKey(password: String): SecretKey {
+            val keyBytes = password.toByteArray().copyOf(16)
+            return SecretKeySpec(keyBytes, ALGORITHM)
+        }
+    }
+} 
--- a/app/src/main/java/devs/org/calculator/utils/StoragePermissionUtil.kt
+++ b/app/src/main/java/devs/org/calculator/utils/StoragePermissionUtil.kt
@@ -0,0 +1,68 @@
+package devs.org.calculator.utils
+
+import android.Manifest
+import android.app.Activity
+import android.content.Intent
+import android.net.Uri
+import android.os.Build
+import android.os.Environment
+import android.provider.Settings
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.app.ActivityCompat
+import androidx.core.content.ContextCompat
+import androidx.core.content.PermissionChecker
+
+class StoragePermissionUtil(private val activity: AppCompatActivity) {
+    
+    private val requestPermissionLauncher = activity.registerForActivityResult(
+        ActivityResultContracts.RequestMultiplePermissions()
+    ) { permissions ->
+        if (permissions.all { it.value }) {
+            onPermissionGranted?.invoke()
+        }
+    }
+
+    private var onPermissionGranted: (() -> Unit)? = null
+
+    fun requestStoragePermission(onGranted: () -> Unit) {
+        onPermissionGranted = onGranted
+        
+        when {
+            Build.VERSION.SDK_INT >= Build.VERSION_CODES.R -> {
+                if (Environment.isExternalStorageManager()) {
+                    onGranted()
+                } else {
+                    val intent = Intent(Settings.ACTION_MANAGE_APP_ALL_FILES_ACCESS_PERMISSION).apply {
+                        data = Uri.parse("package:${activity.packageName}")
+                    }
+                    activity.startActivity(intent)
+                }
+            }
+            else -> {
+                val permissions = arrayOf(
+                    Manifest.permission.READ_EXTERNAL_STORAGE,
+                    Manifest.permission.WRITE_EXTERNAL_STORAGE
+                )
+                requestPermissionLauncher.launch(permissions)
+            }
+        }
+    }
+
+    fun hasStoragePermission(): Boolean {
+        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
+            Environment.isExternalStorageManager()
+        } else {
+            val readPermission = ContextCompat.checkSelfPermission(
+                activity,
+                Manifest.permission.READ_EXTERNAL_STORAGE
+            )
+            val writePermission = ContextCompat.checkSelfPermission(
+                activity,
+                Manifest.permission.WRITE_EXTERNAL_STORAGE
+            )
+            readPermission == PermissionChecker.PERMISSION_GRANTED &&
+                    writePermission == PermissionChecker.PERMISSION_GRANTED
+        }
+    }
+} 
--- a/app/src/main/java/devs/org/calculator/views/SquareImageView.kt
+++ b/app/src/main/java/devs/org/calculator/views/SquareImageView.kt
@@ -0,0 +1,16 @@
+package devs.org.calculator.views
+
+import android.content.Context
+import android.util.AttributeSet
+import androidx.appcompat.widget.AppCompatImageView
+
+class SquareImageView @JvmOverloads constructor(
+    context: Context,
+    attrs: AttributeSet? = null,
+    defStyleAttr: Int = 0
+) : AppCompatImageView(context, attrs, defStyleAttr) {
+
+    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
+        super.onMeasure(widthMeasureSpec, widthMeasureSpec)
+    }
+} 
--- a/app/src/main/res/drawable/ic_audio.xml
+++ b/app/src/main/res/drawable/ic_audio.xml
@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M12,3v9.28c-0.47,-0.17 -0.97,-0.28 -1.5,-0.28C8.01,12 6,14.01 6,16.5S8.01,21 10.5,21c2.31,0 4.2,-1.75 4.45,-4H15V6h4V3h-7z"/>
+</vector> 
--- a/app/src/main/res/drawable/ic_document.xml
+++ b/app/src/main/res/drawable/ic_document.xml
@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M14,2H6C4.9,2 4,2.9 4,4v16c0,1.1 0.9,2 2,2h12c1.1,0 2,-0.9 2,-2V8L14,2zM16,18H8v-2h8V18zM16,14H8v-2h8V14zM13,9V3.5L18.5,9H13z"/>
+</vector> 
--- a/app/src/main/res/drawable/ic_file.xml
+++ b/app/src/main/res/drawable/ic_file.xml
@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M6,2c-1.1,0 -1.99,0.9 -1.99,2L4,20c0,1.1 0.89,2 1.99,2H18c1.1,0 2,-0.9 2,-2V8l-6,-6H6zM13,9V3.5L18.5,9H13z"/>
+</vector> 
--- a/app/src/main/res/drawable/ic_image.xml
+++ b/app/src/main/res/drawable/ic_image.xml
@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M21,19V5c0,-1.1 -0.9,-2 -2,-2H5c-1.1,0 -2,0.9 -2,2v14c0,1.1 0.9,2 2,2h14c1.1,0 2,-0.9 2,-2zM8.5,13.5l2.5,3.01L14.5,12l4.5,6H5l3.5,-4.5z"/>
+</vector> 
--- a/app/src/main/res/drawable/ic_launcher_background.xml
+++ b/app/src/main/res/drawable/ic_launcher_background.xml
@@ -0,0 +1,170 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:fillColor="#3DDC84"
+        android:pathData="M0,0h108v108h-108z" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M9,0L9,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,0L19,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,0L29,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,0L39,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,0L49,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,0L59,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,0L69,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,0L79,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M89,0L89,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M99,0L99,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,9L108,9"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,19L108,19"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,29L108,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,39L108,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,49L108,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,59L108,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,69L108,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,79L108,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,89L108,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,99L108,99"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,29L89,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,39L89,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,49L89,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,59L89,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,69L89,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,79L89,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,19L29,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,19L39,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,19L49,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,19L59,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,19L69,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,19L79,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+</vector>
--- a/app/src/main/res/drawable/ic_launcher_foreground.xml
+++ b/app/src/main/res/drawable/ic_launcher_foreground.xml
@@ -0,0 +1,30 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path android:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="85.84757"
+                android:endY="92.4963"
+                android:startX="42.9492"
+                android:startY="49.59793"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0" />
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>
--- a/app/src/main/res/layout/activity_audio_gallery.xml
+++ b/app/src/main/res/layout/activity_audio_gallery.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".activities.AudioGalleryActivity">
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_documents.xml
+++ b/app/src/main/res/layout/activity_documents.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".activities.DocumentsActivity">
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_gallery.xml
+++ b/app/src/main/res/layout/activity_gallery.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/recyclerView"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:padding="8dp" />
+
+    <com.google.android.material.floatingactionbutton.FloatingActionButton
+        android:id="@+id/fabAdd"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="bottom|end"
+        android:layout_margin="16dp"
+        android:contentDescription="Add file"
+        android:src="@android:drawable/ic_input_add" />
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout> 
--- a/app/src/main/res/layout/activity_gallery_base.xml
+++ b/app/src/main/res/layout/activity_gallery_base.xml
@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.coordinatorlayout.widget.CoordinatorLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/recyclerView"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:padding="8dp" />
+
+    <com.google.android.material.floatingactionbutton.FloatingActionButton
+        android:id="@+id/fabAdd"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="bottom|end"
+        android:layout_margin="16dp"
+        android:src="@android:drawable/ic_input_add" />
+
+</androidx.coordinatorlayout.widget.CoordinatorLayout>
--- a/app/src/main/res/layout/activity_hidden_vault.xml
+++ b/app/src/main/res/layout/activity_hidden_vault.xml
@@ -0,0 +1,121 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:gravity="center"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <LinearLayout
+        android:id="@+id/linearLayout"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_weight="2"
+        android:minHeight="300dp"
+        android:orientation="vertical"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent">
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_weight="1"
+        android:gravity="center_horizontal|bottom"
+        android:orientation="horizontal">
+
+        <com.google.android.material.card.MaterialCardView
+            android:id="@+id/btnImages"
+            android:layout_width="150dp"
+            android:layout_height="150dp"
+            android:layout_margin="8dp"
+            app:cardCornerRadius="12dp"
+            app:layout_constraintBottom_toTopOf="@id/btnAudio"
+            app:layout_constraintEnd_toStartOf="@id/btnVideos"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@+id/linearLayout">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center"
+                android:text="Images"
+                android:textSize="18sp"
+                android:textStyle="bold" />
+        </com.google.android.material.card.MaterialCardView>
+
+        <com.google.android.material.card.MaterialCardView
+            android:id="@+id/btnVideos"
+            android:layout_width="150dp"
+            android:layout_height="150dp"
+            android:layout_margin="8dp"
+            app:cardCornerRadius="12dp"
+            app:layout_constraintBottom_toTopOf="@id/btnDocs"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toEndOf="@id/btnImages"
+            app:layout_constraintTop_toBottomOf="@+id/linearLayout">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center"
+                android:text="Videos"
+                android:textSize="18sp"
+                android:textStyle="bold" />
+        </com.google.android.material.card.MaterialCardView>
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_weight="1"
+        android:gravity="center_horizontal|top"
+        android:orientation="horizontal">
+
+        <com.google.android.material.card.MaterialCardView
+            android:id="@+id/btnAudio"
+            android:layout_width="150dp"
+            android:layout_height="150dp"
+            android:layout_margin="8dp"
+            app:cardCornerRadius="12dp"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toStartOf="@id/btnDocs"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/btnImages">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center"
+                android:text="Audio"
+                android:textSize="18sp"
+                android:textStyle="bold" />
+        </com.google.android.material.card.MaterialCardView>
+
+        <com.google.android.material.card.MaterialCardView
+            android:id="@+id/btnDocs"
+            android:layout_width="150dp"
+            android:layout_height="150dp"
+            android:layout_margin="8dp"
+            app:cardCornerRadius="12dp"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toEndOf="@id/btnAudio"
+            app:layout_constraintTop_toBottomOf="@id/btnVideos">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center"
+                android:text="Documents"
+                android:textSize="18sp"
+                android:textStyle="bold" />
+        </com.google.android.material.card.MaterialCardView>
+    </LinearLayout>
+
+
+</LinearLayout>
--- a/app/src/main/res/layout/activity_image_gallery.xml
+++ b/app/src/main/res/layout/activity_image_gallery.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".activities.ImageGalleryActivity">
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -0,0 +1,273 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:orientation="vertical"
+    android:layout_height="match_parent"
+    tools:context=".activities.MainActivity">
+
+    <!-- Calculator Display -->
+    <TextView
+        android:id="@+id/display"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        android:layout_weight="2"
+        android:layout_marginTop="0dp"
+        android:background="#00000000"
+        android:elevation="4dp"
+        android:gravity="end|bottom"
+        android:padding="10dp"
+        android:text="0"
+        android:textSize="48sp"
+        tools:ignore="Suspicious0dp" />
+
+
+    <!-- Calculator Buttons -->
+    <GridLayout
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_margin="8dp"
+        android:columnCount="4"
+        android:layout_weight="5"
+        android:rowCount="5">
+
+        <!-- Row 1 -->
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnClear"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:layout_margin="4dp"
+            android:textSize="30sp"
+            android:text="C"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnParentheses"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="( )"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnPercent"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="%"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnDivide"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="÷"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button"/>
+
+        <!-- Row 2 -->
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn7"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="7"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn8"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="8"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn9"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:layout_margin="4dp"
+            android:textSize="30sp"
+            android:text="9"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnMultiply"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:layout_margin="4dp"
+            android:textSize="30sp"
+            android:text="×"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button"/>
+
+        <!-- Row 3 -->
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn4"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            app:cornerRadius="15dp"
+            android:text="4"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn5"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="5"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn6"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="6"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnMinus"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="-"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button"/>
+
+        <!-- Row 4 -->
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn1"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="1"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn2"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:textSize="30sp"
+            android:layout_columnWeight="1"
+            android:layout_margin="4dp"
+            android:text="2"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn3"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:textSize="30sp"
+            android:layout_columnWeight="1"
+            android:layout_margin="4dp"
+            android:text="3"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnPlus"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="+"
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button"/>
+
+        <!-- Row 5 -->
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btn0"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnSpan="2"
+            android:textSize="30sp"
+            android:layout_columnWeight="2"
+            android:layout_margin="4dp"
+            app:cornerRadius="15dp"
+            android:text="0" />
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnDot"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:layout_columnWeight="1"
+            android:textSize="30sp"
+            android:layout_margin="4dp"
+            android:text="."
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button.OutlinedButton"/>
+
+        <com.google.android.material.button.MaterialButton
+            android:id="@+id/btnEquals"
+            android:layout_width="0dp"
+            android:layout_height="0dp"
+            android:layout_rowWeight="1"
+            android:textSize="30sp"
+            android:layout_columnWeight="1"
+            android:layout_margin="4dp"
+            android:text="="
+            app:cornerRadius="15dp"
+            style="@style/Widget.MaterialComponents.Button"/>
+
+    </GridLayout>
+
+</LinearLayout>
--- a/app/src/main/res/layout/activity_preview.xml
+++ b/app/src/main/res/layout/activity_preview.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <androidx.appcompat.widget.Toolbar
+        android:id="@+id/toolbar"
+        android:layout_width="match_parent"
+        android:layout_height="?attr/actionBarSize"
+        android:background="?attr/colorPrimary" />
+
+    <androidx.viewpager.widget.ViewPager
+        android:id="@+id/viewPager"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="1" />
+
+</LinearLayout>
--- a/app/src/main/res/layout/activity_setup_password.xml
+++ b/app/src/main/res/layout/activity_setup_password.xml
@@ -0,0 +1,108 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:padding="16dp"
+    tools:context=".activities.SetupPasswordActivity">
+
+    <com.google.android.material.textview.MaterialTextView
+        android:id="@+id/tvTitle"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="Setup Password"
+        android:textSize="24sp"
+        android:textStyle="bold"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <com.google.android.material.textfield.TextInputLayout
+        android:id="@+id/tilPassword"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="32dp"
+        android:hint="Enter Password"
+        app:endIconMode="password_toggle"
+        app:layout_constraintTop_toBottomOf="@id/tvTitle">
+
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/etPassword"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:imeOptions="actionNext"
+            android:singleLine="true"
+            android:inputType="number" />
+    </com.google.android.material.textfield.TextInputLayout>
+
+    <com.google.android.material.textfield.TextInputLayout
+        android:id="@+id/tilConfirmPassword"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:hint="Confirm Password"
+        app:endIconMode="password_toggle"
+        app:layout_constraintTop_toBottomOf="@id/tilPassword">
+
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/etConfirmPassword"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:imeOptions="actionNext"
+            android:singleLine="true"
+            android:inputType="number" />
+    </com.google.android.material.textfield.TextInputLayout>
+
+    <com.google.android.material.textfield.TextInputLayout
+        android:id="@+id/tilSecurityQuestion"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:hint="Security Question (For Password Reset)"
+        app:layout_constraintTop_toBottomOf="@id/tilConfirmPassword">
+
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/etSecurityQuestion"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="text" />
+    </com.google.android.material.textfield.TextInputLayout>
+
+    <com.google.android.material.textfield.TextInputLayout
+        android:id="@+id/tilSecurityAnswer"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:hint="Security Answer"
+        app:layout_constraintTop_toBottomOf="@id/tilSecurityQuestion">
+
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/etSecurityAnswer"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="text" />
+    </com.google.android.material.textfield.TextInputLayout>
+
+    <com.google.android.material.button.MaterialButton
+        android:id="@+id/btnSavePassword"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="32dp"
+        android:padding="12dp"
+        android:text="Save Password"
+        app:layout_constraintTop_toBottomOf="@id/tilSecurityAnswer" />
+
+    <com.google.android.material.button.MaterialButton
+        android:id="@+id/btnResetPassword"
+        style="@style/Widget.MaterialComponents.Button.TextButton"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="8dp"
+        android:text="Forgot Password?"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@id/btnSavePassword" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_splash.xml
+++ b/app/src/main/res/layout/activity_splash.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".activities.SplashActivity">
+
+    <ImageView
+        android:id="@+id/imageView"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        tools:srcCompat="@tools:sample/avatars" />
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/activity_video_gallery.xml
+++ b/app/src/main/res/layout/activity_video_gallery.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/main"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".activities.VideoGalleryActivity">
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/item_file.xml
+++ b/app/src/main/res/layout/item_file.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<com.google.android.material.card.MaterialCardView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_margin="4dp"
+    app:cardCornerRadius="8dp">
+
+    <devs.org.calculator.views.SquareImageView
+        android:id="@+id/imageView"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:scaleType="centerCrop"/>
+
+</com.google.android.material.card.MaterialCardView> 
--- a/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
+++ b/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@mipmap/ic_launcher_background"/>
+    <foreground android:drawable="@mipmap/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
+++ b/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@mipmap/ic_launcher_background"/>
+    <foreground android:drawable="@mipmap/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/app/src/main/res/mipmap-hdpi/ic_launcher.webp
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher.webp
--- a/app/src/main/res/mipmap-hdpi/ic_launcher_background.webp
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher_background.webp
--- a/app/src/main/res/mipmap-hdpi/ic_launcher_foreground.webp
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher_foreground.webp
--- a/app/src/main/res/mipmap-hdpi/ic_launcher_round.webp
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher_round.webp
--- a/app/src/main/res/mipmap-mdpi/ic_launcher.webp
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher.webp
--- a/app/src/main/res/mipmap-mdpi/ic_launcher_background.webp
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher_background.webp
--- a/app/src/main/res/mipmap-mdpi/ic_launcher_foreground.webp
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher_foreground.webp
--- a/app/src/main/res/mipmap-mdpi/ic_launcher_round.webp
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher_round.webp
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher.webp
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher.webp
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher_background.webp
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher_background.webp
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher_foreground.webp
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher_foreground.webp
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher_round.webp
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher_round.webp
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher.webp
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher.webp
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher_background.webp
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher_background.webp
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher_foreground.webp
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher_foreground.webp
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.webp
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.webp
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher.webp
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher.webp
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher_background.webp
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher_background.webp
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher_foreground.webp
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher_foreground.webp
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.webp
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.webp
--- a/app/src/main/res/values-night/themes.xml
+++ b/app/src/main/res/values-night/themes.xml
@@ -0,0 +1,22 @@
+<resources xmlns:tools="http://schemas.android.com/tools">
+    <!-- Base application theme. -->
+    <style name="Base.Theme.Calculator" parent="Theme.Material3.DayNight.NoActionBar">
+        <!-- Primary brand color -->
+        <item name="colorPrimary">@android:color/system_accent1_200</item>
+        <item name="colorPrimaryVariant">@android:color/system_accent1_300</item>
+        <item name="colorOnPrimary">@color/black</item>
+        
+        <!-- Secondary brand color -->
+        <item name="colorSecondary">@android:color/system_accent2_200</item>
+        <item name="colorSecondaryVariant">@android:color/system_accent2_300</item>
+        <item name="colorOnSecondary">@color/black</item>
+        
+        <!-- Status bar color -->
+        <item name="android:statusBarColor">@android:color/transparent</item>
+        <item name="android:navigationBarColor">@android:color/transparent</item>
+        
+        <!-- Enable window decor fitting -->
+        <item name="android:windowLightStatusBar">false</item>
+        <item name="android:windowLightNavigationBar">false</item>
+    </style>
+</resources>
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="black">#FF000000</color>
+    <color name="white">#FFFFFFFF</color>
+    
+    <!-- Material You dynamic colors -->
+    <color name="primary">@android:color/system_accent1_600</color>
+    <color name="on_primary">@android:color/system_accent1_0</color>
+    <color name="primary_container">@android:color/system_accent1_100</color>
+    <color name="on_primary_container">@android:color/system_accent1_900</color>
+    
+    <color name="secondary">@android:color/system_accent2_600</color>
+    <color name="on_secondary">@android:color/system_accent2_0</color>
+    <color name="secondary_container">@android:color/system_accent2_100</color>
+    <color name="on_secondary_container">@android:color/system_accent2_900</color>
+    
+    <color name="surface">@android:color/system_neutral1_50</color>
+    <color name="on_surface">@android:color/system_neutral1_900</color>
+</resources>
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">Calculator</string>
+</resources>
--- a/app/src/main/res/values/themes.xml
+++ b/app/src/main/res/values/themes.xml
@@ -0,0 +1,24 @@
+<resources xmlns:tools="http://schemas.android.com/tools">
+    <!-- Base application theme. -->
+    <style name="Base.Theme.Calculator" parent="Theme.Material3.DayNight.NoActionBar">
+        <!-- Primary brand color -->
+        <item name="colorPrimary">@android:color/system_accent1_600</item>
+        <item name="colorPrimaryVariant">@android:color/system_accent1_700</item>
+        <item name="colorOnPrimary">@color/white</item>
+        
+        <!-- Secondary brand color -->
+        <item name="colorSecondary">@android:color/system_accent2_600</item>
+        <item name="colorSecondaryVariant">@android:color/system_accent2_700</item>
+        <item name="colorOnSecondary">@color/black</item>
+        
+        <!-- Status bar color -->
+        <item name="android:statusBarColor">@android:color/transparent</item>
+        <item name="android:navigationBarColor">@android:color/transparent</item>
+        
+        <!-- Enable window decor fitting -->
+        <item name="android:windowLightStatusBar">true</item>
+        <item name="android:windowLightNavigationBar">true</item>
+    </style>
+
+    <style name="Theme.Calculator" parent="Base.Theme.Calculator" />
+</resources>
--- a/app/src/main/res/xml/backup_rules.xml
+++ b/app/src/main/res/xml/backup_rules.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample backup rules file; uncomment and customize as necessary.
+   See https://developer.android.com/guide/topics/data/autobackup
+   for details.
+   Note: This file is ignored for devices older that API 31
+   See https://developer.android.com/about/versions/12/backup-restore
+-->
+<full-backup-content>
+    <!--
+   <include domain="sharedpref" path="."/>
+   <exclude domain="sharedpref" path="device.xml"/>
+-->
+</full-backup-content>
--- a/app/src/main/res/xml/data_extraction_rules.xml
+++ b/app/src/main/res/xml/data_extraction_rules.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample data extraction rules file; uncomment and customize as necessary.
+   See https://developer.android.com/about/versions/12/backup-restore#xml-changes
+   for details.
+-->
+<data-extraction-rules>
+    <cloud-backup>
+        <!-- TODO: Use <include> and <exclude> to control what is backed up.
+        <include .../>
+        <exclude .../>
+        -->
+    </cloud-backup>
+    <!--
+    <device-transfer>
+        <include .../>
+        <exclude .../>
+    </device-transfer>
+    -->
+</data-extraction-rules>
--- a/app/src/test/java/devs/org/calculator/ExampleUnitTest.kt
+++ b/app/src/test/java/devs/org/calculator/ExampleUnitTest.kt
@@ -0,0 +1,17 @@
+package devs.org.calculator
+
+import org.junit.Test
+
+import org.junit.Assert.*
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+class ExampleUnitTest {
+    @Test
+    fun addition_isCorrect() {
+        assertEquals(4, 2 + 2)
+    }
+}