Add DocumentsProvider for working directory

Expose the service's running directory to file managers via Storage
Access Framework, allowing users to browse and manage files directly.

app/src/main/AndroidManifest.xml

@@ -225,6 +225,17 @@
                 android:resource="@xml/cache_paths" />
         </provider>
 
+        <provider
+            android:name=".WorkingDirectoryProvider"
+            android:authorities="${applicationId}.workingdir"
+            android:exported="true"
+            android:grantUriPermissions="true"
+            android:permission="android.permission.MANAGE_DOCUMENTS">
+            <intent-filter>
+                <action android:name="android.content.action.DOCUMENTS_PROVIDER" />
+            </intent-filter>
+        </provider>
+
     </application>
 
 </manifest>

app/src/main/java/io/nekohasekai/sfa/WorkingDirectoryProvider.kt

@@ -0,0 +1,187 @@
+package io.nekohasekai.sfa
+
+import android.database.Cursor
+import android.database.MatrixCursor
+import android.os.CancellationSignal
+import android.os.ParcelFileDescriptor
+import android.provider.DocumentsContract
+import android.provider.DocumentsProvider
+import android.webkit.MimeTypeMap
+import java.io.File
+import java.io.FileNotFoundException
+
+class WorkingDirectoryProvider : DocumentsProvider() {
+
+    companion object {
+        private const val ROOT_ID = "working_directory"
+        private const val ROOT_DOC_ID = "root"
+
+        private val DEFAULT_ROOT_PROJECTION = arrayOf(
+            DocumentsContract.Root.COLUMN_ROOT_ID,
+            DocumentsContract.Root.COLUMN_FLAGS,
+            DocumentsContract.Root.COLUMN_ICON,
+            DocumentsContract.Root.COLUMN_TITLE,
+            DocumentsContract.Root.COLUMN_SUMMARY,
+            DocumentsContract.Root.COLUMN_DOCUMENT_ID,
+        )
+
+        private val DEFAULT_DOCUMENT_PROJECTION = arrayOf(
+            DocumentsContract.Document.COLUMN_DOCUMENT_ID,
+            DocumentsContract.Document.COLUMN_MIME_TYPE,
+            DocumentsContract.Document.COLUMN_DISPLAY_NAME,
+            DocumentsContract.Document.COLUMN_LAST_MODIFIED,
+            DocumentsContract.Document.COLUMN_FLAGS,
+            DocumentsContract.Document.COLUMN_SIZE,
+        )
+    }
+
+    private val baseDir: File
+        get() = context!!.getExternalFilesDir(null)!!
+
+    override fun onCreate(): Boolean = true
+
+    override fun queryRoots(projection: Array<out String>?): Cursor {
+        val result = MatrixCursor(projection ?: DEFAULT_ROOT_PROJECTION)
+        result.newRow().apply {
+            add(DocumentsContract.Root.COLUMN_ROOT_ID, ROOT_ID)
+            add(
+                DocumentsContract.Root.COLUMN_FLAGS,
+                DocumentsContract.Root.FLAG_SUPPORTS_CREATE or
+                    DocumentsContract.Root.FLAG_SUPPORTS_IS_CHILD
+            )
+            add(DocumentsContract.Root.COLUMN_ICON, R.mipmap.ic_launcher)
+            add(DocumentsContract.Root.COLUMN_TITLE, context!!.getString(R.string.app_name))
+            add(DocumentsContract.Root.COLUMN_SUMMARY, context!!.getString(R.string.working_directory))
+            add(DocumentsContract.Root.COLUMN_DOCUMENT_ID, ROOT_DOC_ID)
+        }
+        return result
+    }
+
+    override fun queryDocument(documentId: String, projection: Array<out String>?): Cursor {
+        val result = MatrixCursor(projection ?: DEFAULT_DOCUMENT_PROJECTION)
+        val file = getFileForDocId(documentId)
+        includeFile(result, documentId, file)
+        return result
+    }
+
+    override fun queryChildDocuments(
+        parentDocumentId: String,
+        projection: Array<out String>?,
+        sortOrder: String?
+    ): Cursor {
+        val result = MatrixCursor(projection ?: DEFAULT_DOCUMENT_PROJECTION)
+        val parent = getFileForDocId(parentDocumentId)
+        parent.listFiles()?.forEach { file ->
+            includeFile(result, getDocIdForFile(file), file)
+        }
+        return result
+    }
+
+    override fun openDocument(
+        documentId: String,
+        mode: String,
+        signal: CancellationSignal?
+    ): ParcelFileDescriptor {
+        val file = getFileForDocId(documentId)
+        val accessMode = ParcelFileDescriptor.parseMode(mode)
+        return ParcelFileDescriptor.open(file, accessMode)
+    }
+
+    override fun createDocument(
+        parentDocumentId: String,
+        mimeType: String,
+        displayName: String
+    ): String {
+        val parent = getFileForDocId(parentDocumentId)
+        val file = File(parent, displayName)
+
+        if (mimeType == DocumentsContract.Document.MIME_TYPE_DIR) {
+            file.mkdirs()
+        } else {
+            file.createNewFile()
+        }
+
+        return getDocIdForFile(file)
+    }
+
+    override fun deleteDocument(documentId: String) {
+        val file = getFileForDocId(documentId)
+        if (file.isDirectory) {
+            file.deleteRecursively()
+        } else {
+            file.delete()
+        }
+    }
+
+    override fun renameDocument(documentId: String, displayName: String): String {
+        val file = getFileForDocId(documentId)
+        val newFile = File(file.parentFile, displayName)
+        file.renameTo(newFile)
+        return getDocIdForFile(newFile)
+    }
+
+    override fun isChildDocument(parentDocumentId: String, documentId: String): Boolean {
+        val parent = getFileForDocId(parentDocumentId)
+        val child = getFileForDocId(documentId)
+        return child.absolutePath.startsWith(parent.absolutePath)
+    }
+
+    private fun getFileForDocId(documentId: String): File {
+        if (documentId == ROOT_DOC_ID) {
+            return baseDir
+        }
+        return File(baseDir, documentId)
+    }
+
+    private fun getDocIdForFile(file: File): String {
+        val path = file.absolutePath
+        val basePath = baseDir.absolutePath
+
+        return if (path == basePath) {
+            ROOT_DOC_ID
+        } else {
+            path.removePrefix("$basePath/")
+        }
+    }
+
+    private fun includeFile(result: MatrixCursor, documentId: String, file: File) {
+        var flags = 0
+
+        if (file.isDirectory) {
+            flags = flags or DocumentsContract.Document.FLAG_DIR_SUPPORTS_CREATE
+        } else {
+            flags = flags or DocumentsContract.Document.FLAG_SUPPORTS_WRITE
+        }
+
+        if (file.parentFile?.canWrite() == true) {
+            flags = flags or DocumentsContract.Document.FLAG_SUPPORTS_DELETE
+            flags = flags or DocumentsContract.Document.FLAG_SUPPORTS_RENAME
+        }
+
+        val mimeType = if (file.isDirectory) {
+            DocumentsContract.Document.MIME_TYPE_DIR
+        } else {
+            getMimeType(file)
+        }
+
+        result.newRow().apply {
+            add(DocumentsContract.Document.COLUMN_DOCUMENT_ID, documentId)
+            add(DocumentsContract.Document.COLUMN_MIME_TYPE, mimeType)
+            add(DocumentsContract.Document.COLUMN_DISPLAY_NAME, file.name)
+            add(DocumentsContract.Document.COLUMN_LAST_MODIFIED, file.lastModified())
+            add(DocumentsContract.Document.COLUMN_FLAGS, flags)
+            add(DocumentsContract.Document.COLUMN_SIZE, file.length())
+        }
+    }
+
+    private fun getMimeType(file: File): String {
+        val extension = file.extension.lowercase()
+        if (extension.isNotEmpty()) {
+            val mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension)
+            if (mimeType != null) {
+                return mimeType
+            }
+        }
+        return "application/octet-stream"
+    }
+}

app/src/main/java/io/nekohasekai/sfa/compose/screen/settings/CoreSettingsScreen.kt

@@ -11,8 +11,14 @@ import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.verticalScroll
+import android.content.ActivityNotFoundException
+import android.content.Context
+import android.content.Intent
+import android.provider.DocumentsContract
+import android.widget.Toast
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.outlined.DeleteForever
+import androidx.compose.material.icons.outlined.FolderOpen
 import androidx.compose.material.icons.outlined.Info
 import androidx.compose.material.icons.outlined.Storage
 import androidx.compose.material.icons.outlined.WarningAmber
@@ -217,7 +223,7 @@ fun CoreSettingsScreen(navController: NavController) {
             modifier = Modifier.padding(horizontal = 32.dp, vertical = 8.dp),
         )
 
-        // Destroy Data Card - No dialog, immediate deletion
+        // Working Directory Card
         Card(
             modifier =
                 Modifier
@@ -225,9 +231,37 @@ fun CoreSettingsScreen(navController: NavController) {
                     .padding(horizontal = 16.dp),
             colors =
                 CardDefaults.cardColors(
-                    containerColor = MaterialTheme.colorScheme.errorContainer.copy(alpha = 0.3f),
+                    containerColor = MaterialTheme.colorScheme.surfaceContainer,
                 ),
         ) {
+            // Browse
+            ListItem(
+                headlineContent = {
+                    Text(
+                        stringResource(R.string.browse),
+                        style = MaterialTheme.typography.bodyLarge,
+                    )
+                },
+                leadingContent = {
+                    Icon(
+                        imageVector = Icons.Outlined.FolderOpen,
+                        contentDescription = null,
+                        tint = MaterialTheme.colorScheme.primary,
+                    )
+                },
+                modifier =
+                    Modifier
+                        .clip(RoundedCornerShape(topStart = 12.dp, topEnd = 12.dp))
+                        .clickable {
+                            openInFileManager(context)
+                        },
+                colors =
+                    ListItemDefaults.colors(
+                        containerColor = Color.Transparent,
+                    ),
+            )
+
+            // Destroy
             ListItem(
                 headlineContent = {
                     Text(
@@ -245,7 +279,7 @@ fun CoreSettingsScreen(navController: NavController) {
                 },
                 modifier =
                     Modifier
-                        .clip(RoundedCornerShape(12.dp))
+                        .clip(RoundedCornerShape(bottomStart = 12.dp, bottomEnd = 12.dp))
                         .clickable {
                             scope.launch(Dispatchers.IO) {
                                 val filesDir = context.getExternalFilesDir(null) ?: context.filesDir
@@ -272,3 +306,24 @@ fun CoreSettingsScreen(navController: NavController) {
         Spacer(modifier = Modifier.height(16.dp))
     }
 }
+
+private fun openInFileManager(context: Context) {
+    val authority = "${context.packageName}.workingdir"
+    val rootUri = DocumentsContract.buildRootUri(authority, "working_directory")
+
+    val intent = Intent(Intent.ACTION_VIEW).apply {
+        setDataAndType(rootUri, DocumentsContract.Document.MIME_TYPE_DIR)
+        addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+        addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
+    }
+
+    try {
+        context.startActivity(intent)
+    } catch (e: ActivityNotFoundException) {
+        Toast.makeText(
+            context,
+            context.getString(R.string.no_file_manager),
+            Toast.LENGTH_SHORT
+        ).show()
+    }
+}

app/src/main/res/values/strings.xml

@@ -348,4 +348,6 @@
     <string name="clear_logs">Clear Logs</string>
     <string name="selected_count">%d selected</string>
     <string name="not_selected">Not selected</string>
+    <string name="browse">Browse</string>
+    <string name="no_file_manager">No file manager found</string>
 </resources>