App update module

app/app/build.gradle.kts

@@ -38,6 +38,7 @@ android {
 
     buildFeatures {
         compose = true
+        buildConfig = true
     }
 }
 

app/app/src/main/AndroidManifest.xml

@@ -2,6 +2,7 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
 
     <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
 
     <application
         android:label="@string/app_name"
@@ -16,6 +17,16 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+
+        <provider
+            android:name="androidx.core.content.FileProvider"
+            android:authorities="${applicationId}.fileprovider"
+            android:exported="false"
+            android:grantUriPermissions="true">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/file_paths" />
+        </provider>
     </application>
 
 </manifest>

app/app/src/main/java/de/haushalt/app/StartScreen.kt

@@ -1,42 +1,121 @@
 package de.haushalt.app
 
 import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.aspectRatio
 import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.lazy.grid.GridCells
 import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
+import androidx.compose.material3.Button
 import androidx.compose.material3.Card
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.unit.dp
+import de.haushalt.app.data.AppUpdater
+import de.haushalt.app.data.AppVersion
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+
+private sealed interface UpdateState {
+    data object Idle : UpdateState
+    data object Checking : UpdateState
+    data object NoUpdate : UpdateState
+    data class Available(val version: AppVersion) : UpdateState
+    data object Downloading : UpdateState
+    data class Error(val message: String) : UpdateState
+}
 
 @Composable
 fun StartScreen(onOpenTasks: () -> Unit = {}) {
-    LazyVerticalGrid(
-        columns = GridCells.Adaptive(minSize = 160.dp),
-        modifier = Modifier
-            .fillMaxSize()
-            .padding(16.dp),
-    ) {
-        item {
-            Card(
-                onClick = onOpenTasks,
-                modifier = Modifier
-                    .padding(8.dp)
-                    .aspectRatio(1f),
-            ) {
-                Box(
-                    modifier = Modifier.fillMaxSize(),
-                    contentAlignment = Alignment.Center,
+    val context = LocalContext.current
+    val scope = rememberCoroutineScope()
+    var updateState by remember { mutableStateOf<UpdateState>(UpdateState.Idle) }
+
+    Column(modifier = Modifier.fillMaxSize().padding(16.dp)) {
+        LazyVerticalGrid(
+            columns = GridCells.Adaptive(minSize = 160.dp),
+            modifier = Modifier.weight(1f),
+        ) {
+            item {
+                Card(
+                    onClick = onOpenTasks,
+                    modifier = Modifier
+                        .padding(8.dp)
+                        .aspectRatio(1f),
                 ) {
-                    Text(
-                        text = "Tasks",
-                        style = MaterialTheme.typography.titleLarge,
-                    )
+                    Box(
+                        modifier = Modifier.fillMaxSize(),
+                        contentAlignment = Alignment.Center,
+                    ) {
+                        Text(
+                            text = "Tasks",
+                            style = MaterialTheme.typography.titleLarge,
+                        )
+                    }
+                }
+            }
+        }
+
+        Spacer(Modifier.padding(8.dp))
+
+        Box(modifier = Modifier.fillMaxWidth(), contentAlignment = Alignment.Center) {
+            when (val state = updateState) {
+                UpdateState.Idle -> TextButton(onClick = {
+                    scope.launch {
+                        updateState = UpdateState.Checking
+                        try {
+                            val version = withContext(Dispatchers.IO) { AppUpdater.checkUpdate() }
+                            updateState = if (version != null) UpdateState.Available(version)
+                            else UpdateState.NoUpdate
+                        } catch (e: Exception) {
+                            updateState = UpdateState.Error(e.message ?: "Fehler")
+                        }
+                    }
+                }) { Text("Update prüfen") }
+
+                UpdateState.Checking -> Text("Prüfe…", style = MaterialTheme.typography.bodySmall)
+
+                UpdateState.NoUpdate -> Text(
+                    "App ist aktuell",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+
+                is UpdateState.Available -> Button(onClick = {
+                    scope.launch {
+                        updateState = UpdateState.Downloading
+                        try {
+                            withContext(Dispatchers.IO) {
+                                AppUpdater.downloadAndInstall(context, state.version)
+                            }
+                            updateState = UpdateState.Idle
+                        } catch (e: Exception) {
+                            updateState = UpdateState.Error(e.message ?: "Fehler")
+                        }
+                    }
+                }) { Text("Update installieren (v${state.version.versionCode})") }
+
+                UpdateState.Downloading -> Text(
+                    "Lade herunter…",
+                    style = MaterialTheme.typography.bodySmall,
+                )
+
+                is UpdateState.Error -> TextButton(onClick = { updateState = UpdateState.Idle }) {
+                    Text(state.message, color = MaterialTheme.colorScheme.error)
                 }
             }
         }

app/app/src/main/java/de/haushalt/app/data/ApiClient.kt

@@ -8,23 +8,32 @@ import retrofit2.Retrofit
 import retrofit2.converter.kotlinx.serialization.asConverterFactory
 
 object ApiClient {
-    private const val BASE_URL = "http://192.168.178.34:8080/api/"
+    const val BASE_URL = "http://192.168.178.34:8080/"
+    private const val API_URL = "${BASE_URL}api/"
 
     private val json = Json {
         ignoreUnknownKeys = true
         explicitNulls = false
     }
 
-    private val okHttp: OkHttpClient = OkHttpClient.Builder()
+    val okHttp: OkHttpClient = OkHttpClient.Builder()
         .addInterceptor(
             HttpLoggingInterceptor().apply { level = HttpLoggingInterceptor.Level.BASIC }
         )
         .build()
 
-    val taskApi: TaskApi = Retrofit.Builder()
+    private val retrofit: Retrofit = Retrofit.Builder()
+        .baseUrl(API_URL)
+        .client(okHttp)
+        .addConverterFactory(json.asConverterFactory("application/json".toMediaType()))
+        .build()
+
+    val taskApi: TaskApi = retrofit.create(TaskApi::class.java)
+
+    val appUpdateApi: AppUpdateApi = Retrofit.Builder()
         .baseUrl(BASE_URL)
         .client(okHttp)
         .addConverterFactory(json.asConverterFactory("application/json".toMediaType()))
         .build()
-        .create(TaskApi::class.java)
+        .create(AppUpdateApi::class.java)
 }

app/app/src/main/java/de/haushalt/app/data/AppUpdateApi.kt

@@ -0,0 +1,15 @@
+package de.haushalt.app.data
+
+import kotlinx.serialization.Serializable
+import retrofit2.http.GET
+
+interface AppUpdateApi {
+    @GET("app/version.json")
+    suspend fun getVersion(): AppVersion
+}
+
+@Serializable
+data class AppVersion(
+    val versionCode: Int,
+    val apkFile: String,
+)

app/app/src/main/java/de/haushalt/app/data/AppUpdater.kt

@@ -0,0 +1,36 @@
+package de.haushalt.app.data
+
+import android.content.Context
+import android.content.Intent
+import androidx.core.content.FileProvider
+import de.haushalt.app.BuildConfig
+import okhttp3.Request
+import java.io.File
+
+object AppUpdater {
+    suspend fun checkUpdate(): AppVersion? {
+        val remote = ApiClient.appUpdateApi.getVersion()
+        return if (remote.versionCode > BuildConfig.VERSION_CODE) remote else null
+    }
+
+    fun downloadAndInstall(context: Context, version: AppVersion) {
+        val apkUrl = "${ApiClient.BASE_URL}app/${version.apkFile}"
+        val apkFile = File(context.cacheDir, "apk/haushalt.apk")
+        apkFile.parentFile?.mkdirs()
+
+        val request = Request.Builder().url(apkUrl).build()
+        ApiClient.okHttp.newCall(request).execute().use { response ->
+            apkFile.outputStream().use { out ->
+                response.body!!.byteStream().copyTo(out)
+            }
+        }
+
+        val uri = FileProvider.getUriForFile(context, "${context.packageName}.fileprovider", apkFile)
+        val intent = Intent(Intent.ACTION_VIEW).apply {
+            setDataAndType(uri, "application/vnd.android.package-archive")
+            addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+            addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
+        }
+        context.startActivity(intent)
+    }
+}

app/app/src/main/res/xml/file_paths.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<paths>
+    <cache-path name="apk" path="apk/" />
+</paths>