[Android] Implement native file picker support

4 files changed, 248 insertions, 0 deletions

diff --git a/platform/android/java/lib/src/org/godotengine/godot/Godot.kt b/platform/android/java/lib/src/org/godotengine/godot/Godot.kt
index 9ad1e0b740..898e3e04be 100644
--- a/platform/android/java/lib/src/org/godotengine/godot/Godot.kt
+++ b/platform/android/java/lib/src/org/godotengine/godot/Godot.kt
@@ -57,6 +57,7 @@ import com.google.android.vending.expansion.downloader.*
 import org.godotengine.godot.error.Error
 import org.godotengine.godot.input.GodotEditText
 import org.godotengine.godot.input.GodotInputHandler
+import org.godotengine.godot.io.FilePicker
 import org.godotengine.godot.io.directory.DirectoryAccessHandler
 import org.godotengine.godot.io.file.FileAccessHandler
 import org.godotengine.godot.plugin.AndroidRuntimePlugin
@@ -677,6 +678,9 @@ class Godot(private val context: Context) {
 		for (plugin in pluginRegistry.allPlugins) {
 			plugin.onMainActivityResult(requestCode, resultCode, data)
 		}
+		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+			FilePicker.handleActivityResult(context, requestCode, resultCode, data)
+		}
 	}
 
 	/**
@@ -890,6 +894,13 @@ class Godot(private val context: Context) {
 		mClipboard.setPrimaryClip(clip)
 	}
 
+	@Keep
+	private fun showFilePicker(currentDirectory: String, filename: String, fileMode: Int, filters: Array<String>) {
+		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+			FilePicker.showFilePicker(context, getActivity(), currentDirectory, filename, fileMode, filters)
+		}
+	}
+
 	/**
 	 * Popup a dialog to input text.
 	 */
diff --git a/platform/android/java/lib/src/org/godotengine/godot/GodotLib.java b/platform/android/java/lib/src/org/godotengine/godot/GodotLib.java
index 3c58e05dda..13ae2150d7 100644
--- a/platform/android/java/lib/src/org/godotengine/godot/GodotLib.java
+++ b/platform/android/java/lib/src/org/godotengine/godot/GodotLib.java
@@ -230,6 +230,11 @@ public class GodotLib {
 	public static native void inputDialogCallback(String p_text);
 
 	/**
+	 * Invoked on the file picker closed.
+	 */
+	public static native void filePickerCallback(boolean p_ok, String[] p_selected_paths);
+
+	/**
 	 * Invoked on the GL thread to configure the height of the virtual keyboard.
 	 */
 	public static native void setVirtualKeyboardHeight(int p_height);
diff --git a/platform/android/java/lib/src/org/godotengine/godot/io/FilePicker.kt b/platform/android/java/lib/src/org/godotengine/godot/io/FilePicker.kt
new file mode 100644
index 0000000000..2befe0583b
--- /dev/null
+++ b/platform/android/java/lib/src/org/godotengine/godot/io/FilePicker.kt
@@ -0,0 +1,160 @@
+/**************************************************************************/
+/*  FilePicker.kt                                                         */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+package org.godotengine.godot.io
+
+import android.app.Activity
+import android.content.Context
+import android.content.Intent
+import android.net.Uri
+import android.os.Build
+import android.provider.DocumentsContract
+import android.util.Log
+import androidx.annotation.RequiresApi
+import org.godotengine.godot.GodotLib
+import org.godotengine.godot.io.file.MediaStoreData
+
+/**
+ * Utility class for managing file selection and file picker activities.
+ *
+ * It provides methods to launch a file picker and handle the result, supporting various file modes,
+ * including opening files, directories, and saving files.
+ */
+internal class FilePicker {
+	companion object {
+		private const val FILE_PICKER_REQUEST = 1000
+		private val TAG = FilePicker::class.java.simpleName
+
+		// Constants for fileMode values
+		private const val FILE_MODE_OPEN_FILE = 0
+		private const val FILE_MODE_OPEN_FILES = 1
+		private const val FILE_MODE_OPEN_DIR = 2
+		private const val FILE_MODE_OPEN_ANY = 3
+		private const val FILE_MODE_SAVE_FILE = 4
+
+		/**
+		 * Handles the result from a file picker activity and processes the selected file(s) or directory.
+		 *
+		 * @param context The context from which the file picker was launched.
+		 * @param requestCode The request code used when starting the file picker activity.
+		 * @param resultCode The result code returned by the activity.
+		 * @param data The intent data containing the selected file(s) or directory.
+		 */
+		@RequiresApi(Build.VERSION_CODES.Q)
+		fun handleActivityResult(context: Context, requestCode: Int, resultCode: Int, data: Intent?) {
+			if (requestCode == FILE_PICKER_REQUEST) {
+				if (resultCode == Activity.RESULT_CANCELED) {
+					Log.d(TAG, "File picker canceled")
+					GodotLib.filePickerCallback(false, emptyArray())
+					return
+				}
+				if (resultCode == Activity.RESULT_OK) {
+					val selectedPaths: MutableList<String> = mutableListOf()
+					// Handle multiple file selection.
+					val clipData = data?.clipData
+					if (clipData != null) {
+						for (i in 0 until clipData.itemCount) {
+							val uri = clipData.getItemAt(i).uri
+							uri?.let {
+								val filepath = MediaStoreData.getFilePathFromUri(context, uri)
+								if (filepath != null) {
+									selectedPaths.add(filepath)
+								} else {
+									Log.d(TAG, "null filepath URI: $it")
+								}
+							}
+						}
+					} else {
+						val uri: Uri? = data?.data
+						uri?.let {
+							val filepath = MediaStoreData.getFilePathFromUri(context, uri)
+							if (filepath != null) {
+								selectedPaths.add(filepath)
+							} else {
+								Log.d(TAG, "null filepath URI: $it")
+							}
+						}
+					}
+
+					if (selectedPaths.isNotEmpty()) {
+						GodotLib.filePickerCallback(true, selectedPaths.toTypedArray())
+					} else {
+						GodotLib.filePickerCallback(false, emptyArray())
+					}
+				}
+			}
+		}
+
+		/**
+		 * Launches a file picker activity with specified settings based on the mode, initial directory,
+		 * file type filters, and other parameters.
+		 *
+		 * @param context The context from which to start the file picker.
+		 * @param activity The activity instance used to initiate the picker. Required for activity results.
+		 * @param currentDirectory The directory path to start the file picker in.
+		 * @param filename The name of the file when using save mode.
+		 * @param fileMode The mode to operate in, specifying open, save, or directory select.
+		 * @param filters Array of MIME types to filter file selection.
+		 */
+		@RequiresApi(Build.VERSION_CODES.Q)
+		fun showFilePicker(context: Context, activity: Activity?, currentDirectory: String, filename: String, fileMode: Int, filters: Array<String>) {
+			val intent = when (fileMode) {
+				FILE_MODE_OPEN_DIR -> Intent(Intent.ACTION_OPEN_DOCUMENT_TREE)
+				FILE_MODE_SAVE_FILE -> Intent(Intent.ACTION_CREATE_DOCUMENT)
+				else -> Intent(Intent.ACTION_OPEN_DOCUMENT)
+			}
+			val initialDirectory = MediaStoreData.getUriFromDirectoryPath(context, currentDirectory)
+			if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q && initialDirectory != null) {
+				intent.putExtra(DocumentsContract.EXTRA_INITIAL_URI, initialDirectory)
+			} else {
+				Log.d(TAG, "Error cannot set initial directory")
+			}
+			if (fileMode == FILE_MODE_OPEN_FILES) {
+				intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true) // Set multi select for FILE_MODE_OPEN_FILES
+			} else if (fileMode == FILE_MODE_SAVE_FILE) {
+				intent.putExtra(Intent.EXTRA_TITLE, filename) // Set filename for FILE_MODE_SAVE_FILE
+			}
+			// ACTION_OPEN_DOCUMENT_TREE does not support intent type
+			if (fileMode != FILE_MODE_OPEN_DIR) {
+				intent.type = "*/*"
+				if (filters.isNotEmpty()) {
+					if (filters.size == 1) {
+						intent.type = filters[0]
+					} else {
+						intent.putExtra(Intent.EXTRA_MIME_TYPES, filters)
+					}
+				}
+				intent.addCategory(Intent.CATEGORY_OPENABLE)
+			}
+			intent.putExtra(Intent.EXTRA_LOCAL_ONLY, true)
+			activity?.startActivityForResult(intent, FILE_PICKER_REQUEST)
+		}
+	}
+}
diff --git a/platform/android/java/lib/src/org/godotengine/godot/io/file/MediaStoreData.kt b/platform/android/java/lib/src/org/godotengine/godot/io/file/MediaStoreData.kt
index 97362e2542..46bd465e90 100644
--- a/platform/android/java/lib/src/org/godotengine/godot/io/file/MediaStoreData.kt
+++ b/platform/android/java/lib/src/org/godotengine/godot/io/file/MediaStoreData.kt
@@ -38,6 +38,7 @@ import android.net.Uri
 import android.os.Build
 import android.os.Environment
 import android.provider.MediaStore
+import android.util.Log
 import androidx.annotation.RequiresApi
 
 import java.io.File
@@ -46,6 +47,7 @@ import java.io.FileNotFoundException
 import java.io.FileOutputStream
 import java.nio.channels.FileChannel
 
+
 /**
  * Implementation of [DataAccess] which handles access and interactions with file and data
  * under scoped storage via the MediaStore API.
@@ -81,6 +83,10 @@ internal class MediaStoreData(context: Context, filePath: String, accessFlag: Fi
 		private const val SELECTION_BY_PATH = "${MediaStore.Files.FileColumns.DISPLAY_NAME} = ? " +
 			" AND ${MediaStore.Files.FileColumns.RELATIVE_PATH} = ?"
 
+		private const val AUTHORITY_MEDIA_DOCUMENTS = "com.android.providers.media.documents"
+		private const val AUTHORITY_EXTERNAL_STORAGE_DOCUMENTS = "com.android.externalstorage.documents"
+		private const val AUTHORITY_DOWNLOADS_DOCUMENTS = "com.android.providers.downloads.documents"
+
 		private fun getSelectionByPathArguments(path: String): Array<String> {
 			return arrayOf(getMediaStoreDisplayName(path), getMediaStoreRelativePath(path))
 		}
@@ -230,6 +236,72 @@ internal class MediaStoreData(context: Context, filePath: String, accessFlag: Fi
 			)
 			return updated > 0
 		}
+
+		fun getUriFromDirectoryPath(context: Context, directoryPath: String): Uri? {
+			if (!directoryExists(directoryPath)) {
+				return null
+			}
+			// Check if the path is under external storage.
+			val externalStorageRoot = Environment.getExternalStorageDirectory().absolutePath
+			if (directoryPath.startsWith(externalStorageRoot)) {
+				val relativePath = directoryPath.replaceFirst(externalStorageRoot, "").trim('/')
+				val uri = Uri.Builder()
+					.scheme("content")
+					.authority(AUTHORITY_EXTERNAL_STORAGE_DOCUMENTS)
+					.appendPath("document")
+					.appendPath("primary:$relativePath")
+					.build()
+				return uri
+			}
+			return null
+		}
+
+		fun getFilePathFromUri(context: Context, uri: Uri): String? {
+			// Converts content uri to filepath.
+			val id = getIdFromUri(uri) ?: return null
+
+			if (uri.authority == AUTHORITY_EXTERNAL_STORAGE_DOCUMENTS) {
+				val split = id.split(":")
+				val fileName = split.last()
+				val relativePath = split.dropLast(1).joinToString("/")
+				val fullPath = File(Environment.getExternalStorageDirectory(), "$relativePath/$fileName").absolutePath
+				return fullPath
+			} else {
+				val id = id.toLongOrNull() ?: return null
+				val dataItems = queryById(context, id)
+				return if (dataItems.isNotEmpty()) {
+					val dataItem = dataItems[0]
+					File(Environment.getExternalStorageDirectory(), File(dataItem.relativePath, dataItem.displayName).toString()).absolutePath
+				} else {
+					null
+				}
+			}
+		}
+
+		private fun getIdFromUri(uri: Uri): String? {
+			return try {
+				if (uri.authority == AUTHORITY_EXTERNAL_STORAGE_DOCUMENTS || uri.authority == AUTHORITY_MEDIA_DOCUMENTS || uri.authority == AUTHORITY_DOWNLOADS_DOCUMENTS) {
+					val documentId = uri.lastPathSegment ?: throw IllegalArgumentException("Invalid URI: $uri")
+					documentId.substringAfter(":")
+				} else {
+					throw IllegalArgumentException("Unsupported URI format: $uri")
+				}
+			} catch (e: Exception) {
+				Log.d(TAG, "Failed to parse ID from URI: $uri", e)
+				null
+			}
+		}
+
+		private fun directoryExists(path: String): Boolean {
+			return try {
+				val file = File(path)
+				file.isDirectory && file.exists()
+			} catch (e: SecurityException) {
+				Log.d(TAG, "Failed to check directoryExists: $path", e)
+				false
+			}
+		}
+
 	}
 
 	private val id: Long