refactor(desktop): Save downloads to user's Downloads folder

This commit changes the download location for desktop platforms (Windows, macOS, Linux) from a temporary, app-specific directory to the standard user "Downloads" folder.

Key changes:
-   Introduced a `userDownloadsDir()` function in `FileLocationsProvider` to abstract the platform-specific path to the user's Downloads directory.
-   Implemented `userDownloadsDir()` in `DesktopFileLocationsProvider` to correctly resolve the Downloads path for Windows, macOS, and Linux (including XDG support).
-   Updated `DesktopDownloader` to use the new `userDownloadsDir()` for saving downloaded files.
-   Added a Snackbar notification on desktop to inform the user that the installer has been saved to their Downloads folder, as auto-installation is not performed.
-   The `saveInstalledAppToDatabase` logic is now skipped for desktop platforms, as the app is not "installed" in the same way as on Android.

Author: rainxchzed

composeApp/release/baselineProfiles/0/composeApp-release.dm

@@ -1,6 +1,8 @@
 package zed.rainxch.githubstore.feature.details.data
 
 import android.content.Context
+import android.os.Build
+import android.os.Environment
 import java.io.File
 
 class AndroidFileLocationsProvider(
@@ -13,6 +15,10 @@ class AndroidFileLocationsProvider(
         return dir.absolutePath
     }
 
+    override fun userDownloadsDir(): String {
+        return "" // No-op
+    }
+
     override fun setExecutableIfNeeded(path: String) {
         // No-op on Android
     }

composeApp/release/baselineProfiles/1/composeApp-release.dm

@@ -2,5 +2,6 @@ package zed.rainxch.githubstore.feature.details.data
 
 interface FileLocationsProvider {
     fun appDownloadsDir(): String
+    fun userDownloadsDir(): String
     fun setExecutableIfNeeded(path: String)
 }

composeApp/src/androidMain/kotlin/zed/rainxch/githubstore/feature/details/data/AndroidFileLocationsProvider.kt

@@ -3,4 +3,5 @@ package zed.rainxch.githubstore.feature.details.presentation
 sealed interface DetailsEvent {
     data class OnOpenRepositoryInApp(val repositoryId: Int) : DetailsEvent
     data class InstallTrackingFailed(val message: String) : DetailsEvent
+    data class OnMessage(val message: String) : DetailsEvent
 }

composeApp/src/commonMain/kotlin/zed/rainxch/githubstore/feature/details/data/FileLocationsProvider.kt

@@ -19,11 +19,15 @@ import androidx.compose.material3.IconButton
 import androidx.compose.material3.IconButtonDefaults
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Scaffold
+import androidx.compose.material3.SnackbarHost
+import androidx.compose.material3.SnackbarHostState
 import androidx.compose.material3.TopAppBar
 import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
@@ -32,6 +36,7 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import io.github.fletchmckee.liquid.liquefiable
 import io.github.fletchmckee.liquid.liquid
 import io.github.fletchmckee.liquid.rememberLiquidState
+import kotlinx.coroutines.launch
 import org.jetbrains.compose.ui.tooling.preview.Preview
 import org.koin.compose.viewmodel.koinViewModel
 import zed.rainxch.githubstore.core.presentation.theme.GithubStoreTheme
@@ -53,6 +58,8 @@ fun DetailsRoot(
     viewModel: DetailsViewModel = koinViewModel()
 ) {
     val state by viewModel.state.collectAsStateWithLifecycle()
+    val snackbarHostState = remember { SnackbarHostState() }
+    val coroutineScope = rememberCoroutineScope()
 
     ObserveAsEvents(viewModel.events) { event ->
         when (event) {
@@ -63,11 +70,18 @@ fun DetailsRoot(
             is DetailsEvent.InstallTrackingFailed -> {
 
             }
+
+            is DetailsEvent.OnMessage -> {
+                coroutineScope.launch {
+                    snackbarHostState.showSnackbar(event.message)
+                }
+            }
         }
     }
 
     DetailsScreen(
         state = state,
+        snackbarHostState = snackbarHostState,
         onAction = { action ->
             when (action) {
                 DetailsAction.OnNavigateBackClick -> {
@@ -91,6 +105,7 @@ fun DetailsRoot(
 fun DetailsScreen(
     state: DetailsState,
     onAction: (DetailsAction) -> Unit,
+    snackbarHostState: SnackbarHostState,
 ) {
     val liquidTopbarState = rememberLiquidState()
 
@@ -148,7 +163,10 @@ fun DetailsScreen(
                 )
             },
             containerColor = MaterialTheme.colorScheme.background,
-            modifier = Modifier.liquefiable(liquidTopbarState)
+            modifier = Modifier.liquefiable(liquidTopbarState),
+            snackbarHost = {
+                SnackbarHost(snackbarHostState)
+            }
         ) { innerPadding ->
 
             if (state.isLoading) {
@@ -216,7 +234,8 @@ private fun Preview() {
             state = DetailsState(
                 isLoading = false
             ),
-            onAction = {}
+            onAction = {},
+            snackbarHostState = SnackbarHostState()
         )
     }
 }

composeApp/src/commonMain/kotlin/zed/rainxch/githubstore/feature/details/presentation/DetailsEvent.kt

@@ -519,20 +519,18 @@ class DetailsViewModel(
                 )
 
                 installer.ensurePermissionsOrThrow(
-                    assetName.substringAfterLast('.', "").lowercase()
+                    extOrMime = assetName.substringAfterLast('.', "").lowercase()
                 )
 
                 _state.value = _state.value.copy(downloadStage = DownloadStage.DOWNLOADING)
-
-                var filePath: String? = null
                 downloader.download(downloadUrl, assetName).collect { p ->
                     _state.value = _state.value.copy(downloadProgressPercent = p.percent)
                     if (p.percent == 100) {
                         _state.value = _state.value.copy(downloadStage = DownloadStage.VERIFYING)
                     }
                 }
 
-                filePath = downloader.getDownloadedFilePath(assetName)
+                val filePath = downloader.getDownloadedFilePath(assetName)
                     ?: throw IllegalStateException("Downloaded file not found")
 
                 appendLog(assetName, sizeBytes, releaseTag, "Downloaded")
@@ -544,14 +542,20 @@ class DetailsViewModel(
                     throw IllegalStateException("Asset type .$ext not supported")
                 }
 
-                saveInstalledAppToDatabase(
-                    assetName = assetName,
-                    assetUrl = downloadUrl,
-                    assetSize = sizeBytes,
-                    releaseTag = releaseTag,
-                    isUpdate = isUpdate,
-                    filePath = filePath
-                )
+                if (platform.type == PlatformType.ANDROID) {
+                    saveInstalledAppToDatabase(
+                        assetName = assetName,
+                        assetUrl = downloadUrl,
+                        assetSize = sizeBytes,
+                        releaseTag = releaseTag,
+                        isUpdate = isUpdate,
+                        filePath = filePath
+                    )
+                } else {
+                    viewModelScope.launch {
+                        _events.send(DetailsEvent.OnMessage("Installer was saved into the Downloads folder"))
+                    }
+                }
 
                 installer.install(filePath, ext)
 

composeApp/src/commonMain/kotlin/zed/rainxch/githubstore/feature/details/presentation/DetailsRoot.kt

@@ -23,7 +23,7 @@ class DesktopDownloader(
 
     override fun download(url: String, suggestedFileName: String?): Flow<DownloadProgress> = channelFlow {
         withContext(Dispatchers.IO) {
-            val dir = File(files.appDownloadsDir())
+            val dir = File(files.userDownloadsDir())
             if (!dir.exists()) dir.mkdirs()
 
             val safeName = (suggestedFileName?.takeIf { it.isNotBlank() }
@@ -72,7 +72,6 @@ class DesktopDownloader(
 
                 trySend(DownloadProgress(total ?: outFile.length(), total, 100))
             } catch (e: CancellationException) {
-                // Delete partial file on cancellation
                 if (outFile.exists()) {
                     outFile.delete()
                     Logger.d { "Deleted partial file after cancellation: ${outFile.absolutePath}" }
@@ -85,7 +84,7 @@ class DesktopDownloader(
     }
 
     override suspend fun saveToFile(url: String, suggestedFileName: String?): String = withContext(Dispatchers.IO) {
-        val dir = File(files.appDownloadsDir())
+        val dir = File(files.userDownloadsDir())
         val safeName = (suggestedFileName?.takeIf { it.isNotBlank() }
             ?: url.substringAfterLast('/')
                 .ifBlank { "asset-${UUID.randomUUID()}" })
@@ -104,7 +103,7 @@ class DesktopDownloader(
     }
 
     override suspend fun getDownloadedFilePath(fileName: String): String? = withContext(Dispatchers.IO) {
-        val dir = File(files.appDownloadsDir())
+        val dir = File(files.userDownloadsDir())
         val file = File(dir, fileName)
 
         if (file.exists() && file.length() > 0) {
@@ -115,15 +114,15 @@ class DesktopDownloader(
     }
 
     override suspend fun cancelDownload(fileName: String): Boolean = withContext(Dispatchers.IO) {
-        val dir = File(files.appDownloadsDir())
+        val dir = File(files.userDownloadsDir())
         val file = File(dir, fileName)
 
         if (file.exists()) {
             val deleted = file.delete()
             if (deleted) {
-                Logger.d { "Deleted cached file: ${file.absolutePath}" }
+                Logger.d { "Deleted file from Downloads: ${file.absolutePath}" }
             } else {
-                Logger.w { "Failed to delete cached file: ${file.absolutePath}" }
+                Logger.w { "Failed to delete file: ${file.absolutePath}" }
             }
             deleted
         } else {

composeApp/src/commonMain/kotlin/zed/rainxch/githubstore/feature/details/presentation/DetailsViewModel.kt

@@ -1,5 +1,6 @@
 package zed.rainxch.githubstore.feature.details.data
 
+import co.touchlab.kermit.Logger
 import zed.rainxch.githubstore.core.domain.model.PlatformType
 import java.io.File
 import java.nio.file.Files
@@ -59,4 +60,61 @@ class DesktopFileLocationsProvider(
             }
         }
     }
+
+    override fun userDownloadsDir(): String {
+        val downloadsDir = when (platform) {
+            PlatformType.WINDOWS -> {
+                val userProfile = System.getenv("USERPROFILE")
+                    ?: System.getProperty("user.home")
+                File(userProfile, "Downloads")
+            }
+            PlatformType.MACOS -> {
+                val home = System.getProperty("user.home")
+                File(home, "Downloads")
+            }
+            PlatformType.LINUX -> {
+                val xdgDownloads = getXdgDownloadsDir()
+                if (xdgDownloads != null) {
+                    File(xdgDownloads)
+                } else {
+                    val home = System.getProperty("user.home")
+                    File(home, "Downloads")
+                }
+            }
+            else -> {
+                File(System.getProperty("user.home"), "Downloads")
+            }
+        }
+
+        if (!downloadsDir.exists()) {
+            downloadsDir.mkdirs()
+        }
+
+        return downloadsDir.absolutePath
+    }
+
+    private fun getXdgDownloadsDir(): String? {
+        return try {
+            val userDirsFile = File(
+                System.getProperty("user.home"),
+                ".config/user-dirs.dirs"
+            )
+
+            if (userDirsFile.exists()) {
+                userDirsFile.readLines().forEach { line ->
+                    if (line.trim().startsWith("XDG_DOWNLOAD_DIR=")) {
+                        val path = line.substringAfter("=")
+                            .trim()
+                            .removeSurrounding("\"")
+                            .replace("\$HOME", System.getProperty("user.home"))
+                        return path
+                    }
+                }
+            }
+            null
+        } catch (e: Exception) {
+            Logger.w { "Failed to read XDG user dirs: ${e.message}" }
+            null
+        }
+    }
 }