Add partial support for Android scoped storage.

This is done by providing API access to app specific directories which don't have any limitations and allows us to bump the target sdk version to 30.
In addition, we're also bumping the min sdk version to 19 as version 18 is no longer supported by Google Play Services and only account of 0.3% of Android devices.

2 files changed, 51 insertions, 201 deletions

diff --git a/platform/android/java/lib/src/org/godotengine/godot/Godot.java b/platform/android/java/lib/src/org/godotengine/godot/Godot.java
index 76751a886c..317175858b 100644
--- a/platform/android/java/lib/src/org/godotengine/godot/Godot.java
+++ b/platform/android/java/lib/src/org/godotengine/godot/Godot.java
@@ -49,7 +49,6 @@ import android.content.ClipData;
 import android.content.ClipboardManager;
 import android.content.ComponentName;
 import android.content.Context;
-import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.content.SharedPreferences.Editor;
@@ -68,15 +67,12 @@ import android.os.Environment;
 import android.os.Messenger;
 import android.os.VibrationEffect;
 import android.os.Vibrator;
-import android.provider.Settings.Secure;
 import android.view.Display;
-import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.Surface;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.ViewGroup.LayoutParams;
-import android.view.ViewTreeObserver;
 import android.view.Window;
 import android.view.WindowManager;
 import android.widget.Button;
@@ -471,7 +467,6 @@ public class Godot extends Fragment implements SensorEventListener, IDownloaderC
 
 		final Activity activity = getActivity();
 		io = new GodotIO(activity);
-		io.unique_id = Secure.getString(activity.getContentResolver(), Secure.ANDROID_ID);
 		GodotLib.io = io;
 		netUtils = new GodotNetUtils(activity);
 		mSensorManager = (SensorManager)activity.getSystemService(Context.SENSOR_SERVICE);
diff --git a/platform/android/java/lib/src/org/godotengine/godot/GodotIO.java b/platform/android/java/lib/src/org/godotengine/godot/GodotIO.java
index 66882e8e72..d85d88ec6c 100644
--- a/platform/android/java/lib/src/org/godotengine/godot/GodotIO.java
+++ b/platform/android/java/lib/src/org/godotengine/godot/GodotIO.java
@@ -30,15 +30,19 @@
 
 package org.godotengine.godot;
 
-import org.godotengine.godot.input.*;
+import org.godotengine.godot.input.GodotEditText;
 
 import android.app.Activity;
-import android.content.*;
+import android.content.ActivityNotFoundException;
+import android.content.Intent;
 import android.content.pm.ActivityInfo;
 import android.content.res.AssetManager;
 import android.graphics.Point;
 import android.net.Uri;
-import android.os.*;
+import android.os.Build;
+import android.os.Environment;
+import android.provider.Settings;
+import android.text.TextUtils;
 import android.util.DisplayMetrics;
 import android.util.Log;
 import android.util.SparseArray;
@@ -47,14 +51,16 @@ import android.view.DisplayCutout;
 import android.view.WindowInsets;
 
 import java.io.IOException;
-import java.io.InputStream;
 import java.util.Locale;
 
 // Wrapper for native library
 
 public class GodotIO {
-	AssetManager am;
-	final Activity activity;
+	private static final String TAG = GodotIO.class.getSimpleName();
+
+	private final AssetManager am;
+	private final Activity activity;
+	private final String uniqueId;
 	GodotEditText edit;
 
 	final int SCREEN_LANDSCAPE = 0;
@@ -66,167 +72,6 @@ public class GodotIO {
 	final int SCREEN_SENSOR = 6;
 
 	/////////////////////////
-	/// FILES
-	/////////////////////////
-
-	public int last_file_id = 1;
-
-	static class AssetData {
-		public boolean eof = false;
-		public String path;
-		public InputStream is;
-		public int len;
-		public int pos;
-	}
-
-	SparseArray<AssetData> streams;
-
-	public int file_open(String path, boolean write) {
-		//System.out.printf("file_open: Attempt to Open %s\n",path);
-
-		//Log.v("MyApp", "TRYING TO OPEN FILE: " + path);
-		if (write)
-			return -1;
-
-		AssetData ad = new AssetData();
-
-		try {
-			ad.is = am.open(path);
-
-		} catch (Exception e) {
-			//System.out.printf("Exception on file_open: %s\n",path);
-			return -1;
-		}
-
-		try {
-			ad.len = ad.is.available();
-		} catch (Exception e) {
-			System.out.printf("Exception availabling on file_open: %s\n", path);
-			return -1;
-		}
-
-		ad.path = path;
-		ad.pos = 0;
-		++last_file_id;
-		streams.put(last_file_id, ad);
-
-		return last_file_id;
-	}
-	public int file_get_size(int id) {
-		if (streams.get(id) == null) {
-			System.out.printf("file_get_size: Invalid file id: %d\n", id);
-			return -1;
-		}
-
-		return streams.get(id).len;
-	}
-	public void file_seek(int id, int bytes) {
-		if (streams.get(id) == null) {
-			System.out.printf("file_get_size: Invalid file id: %d\n", id);
-			return;
-		}
-		//seek sucks
-		AssetData ad = streams.get(id);
-		if (bytes > ad.len)
-			bytes = ad.len;
-		if (bytes < 0)
-			bytes = 0;
-
-		try {
-			if (bytes > (int)ad.pos) {
-				int todo = bytes - (int)ad.pos;
-				while (todo > 0) {
-					todo -= ad.is.skip(todo);
-				}
-				ad.pos = bytes;
-			} else if (bytes < (int)ad.pos) {
-				ad.is = am.open(ad.path);
-
-				ad.pos = bytes;
-				int todo = bytes;
-				while (todo > 0) {
-					todo -= ad.is.skip(todo);
-				}
-			}
-
-			ad.eof = false;
-		} catch (IOException e) {
-			System.out.printf("Exception on file_seek: %s\n", e);
-			return;
-		}
-	}
-
-	public int file_tell(int id) {
-		if (streams.get(id) == null) {
-			System.out.printf("file_read: Can't tell eof for invalid file id: %d\n", id);
-			return 0;
-		}
-
-		AssetData ad = streams.get(id);
-		return ad.pos;
-	}
-	public boolean file_eof(int id) {
-		if (streams.get(id) == null) {
-			System.out.printf("file_read: Can't check eof for invalid file id: %d\n", id);
-			return false;
-		}
-
-		AssetData ad = streams.get(id);
-		return ad.eof;
-	}
-
-	public byte[] file_read(int id, int bytes) {
-		if (streams.get(id) == null) {
-			System.out.printf("file_read: Can't read invalid file id: %d\n", id);
-			return new byte[0];
-		}
-
-		AssetData ad = streams.get(id);
-
-		if (ad.pos + bytes > ad.len) {
-			bytes = ad.len - ad.pos;
-			ad.eof = true;
-		}
-
-		if (bytes == 0) {
-			return new byte[0];
-		}
-
-		byte[] buf1 = new byte[bytes];
-		int r = 0;
-		try {
-			r = ad.is.read(buf1);
-		} catch (IOException e) {
-			System.out.printf("Exception on file_read: %s\n", e);
-			return new byte[bytes];
-		}
-
-		if (r == 0) {
-			return new byte[0];
-		}
-
-		ad.pos += r;
-
-		if (r < bytes) {
-			byte[] buf2 = new byte[r];
-			for (int i = 0; i < r; i++)
-				buf2[i] = buf1[i];
-			return buf2;
-		} else {
-			return buf1;
-		}
-	}
-
-	public void file_close(int id) {
-		if (streams.get(id) == null) {
-			System.out.printf("file_close: Can't close invalid file id: %d\n", id);
-			return;
-		}
-
-		streams.remove(id);
-	}
-
-	/////////////////////////
 	/// DIRECTORIES
 	/////////////////////////
 
@@ -236,9 +81,9 @@ public class GodotIO {
 		public String path;
 	}
 
-	public int last_dir_id = 1;
+	private int last_dir_id = 1;
 
-	SparseArray<AssetDir> dirs;
+	private final SparseArray<AssetDir> dirs;
 
 	public int dir_open(String path) {
 		AssetDir ad = new AssetDir();
@@ -257,7 +102,6 @@ public class GodotIO {
 			return -1;
 		}
 
-		//System.out.printf("Opened dir: %s\n",path);
 		++last_dir_id;
 		dirs.put(last_dir_id, ad);
 
@@ -320,9 +164,14 @@ public class GodotIO {
 	GodotIO(Activity p_activity) {
 		am = p_activity.getAssets();
 		activity = p_activity;
-		//streams = new HashMap<Integer, AssetData>();
-		streams = new SparseArray<>();
 		dirs = new SparseArray<>();
+		String androidId = Settings.Secure.getString(activity.getContentResolver(),
+				Settings.Secure.ANDROID_ID);
+		if (androidId == null) {
+			androidId = "";
+		}
+
+		uniqueId = androidId;
 	}
 
 	/////////////////////////
@@ -331,7 +180,6 @@ public class GodotIO {
 
 	public int openURI(String p_uri) {
 		try {
-			Log.v("MyApp", "TRYING TO OPEN URI: " + p_uri);
 			String path = p_uri;
 			String type = "";
 			if (path.startsWith("/")) {
@@ -357,12 +205,12 @@ public class GodotIO {
 		}
 	}
 
-	public String getDataDir() {
-		return activity.getFilesDir().getAbsolutePath();
+	public String getCacheDir() {
+		return activity.getCacheDir().getAbsolutePath();
 	}
 
-	public String getExternalDataDir() {
-		return activity.getExternalFilesDir(null).getAbsolutePath();
+	public String getDataDir() {
+		return activity.getFilesDir().getAbsolutePath();
 	}
 
 	public String getLocale() {
@@ -456,51 +304,58 @@ public class GodotIO {
 	public static final int SYSTEM_DIR_PICTURES = 6;
 	public static final int SYSTEM_DIR_RINGTONES = 7;
 
-	public String getSystemDir(int idx) {
-		String what = "";
+	public String getSystemDir(int idx, boolean shared_storage) {
+		String what;
 		switch (idx) {
-			case SYSTEM_DIR_DESKTOP: {
-				//what=Environment.DIRECTORY_DOCUMENTS;
-				what = Environment.DIRECTORY_DOWNLOADS;
+			case SYSTEM_DIR_DESKTOP:
+			default: {
+				what = null; // This leads to the app specific external root directory.
 			} break;
+
 			case SYSTEM_DIR_DCIM: {
 				what = Environment.DIRECTORY_DCIM;
-
 			} break;
+
 			case SYSTEM_DIR_DOCUMENTS: {
-				what = Environment.DIRECTORY_DOWNLOADS;
-				//what=Environment.DIRECTORY_DOCUMENTS;
+				what = Environment.DIRECTORY_DOCUMENTS;
 			} break;
+
 			case SYSTEM_DIR_DOWNLOADS: {
 				what = Environment.DIRECTORY_DOWNLOADS;
-
 			} break;
+
 			case SYSTEM_DIR_MOVIES: {
 				what = Environment.DIRECTORY_MOVIES;
-
 			} break;
+
 			case SYSTEM_DIR_MUSIC: {
 				what = Environment.DIRECTORY_MUSIC;
 			} break;
+
 			case SYSTEM_DIR_PICTURES: {
 				what = Environment.DIRECTORY_PICTURES;
 			} break;
+
 			case SYSTEM_DIR_RINGTONES: {
 				what = Environment.DIRECTORY_RINGTONES;
-
 			} break;
 		}
 
-		if (what.equals(""))
-			return "";
-		return Environment.getExternalStoragePublicDirectory(what).getAbsolutePath();
+		if (shared_storage) {
+			if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+				Log.w(TAG, "Shared storage access is limited on Android 10 and higher.");
+			}
+			if (TextUtils.isEmpty(what)) {
+				return Environment.getExternalStorageDirectory().getAbsolutePath();
+			} else {
+				return Environment.getExternalStoragePublicDirectory(what).getAbsolutePath();
+			}
+		} else {
+			return activity.getExternalFilesDir(what).getAbsolutePath();
+		}
 	}
 
-	protected static final String PREFS_FILE = "device_id.xml";
-	protected static final String PREFS_DEVICE_ID = "device_id";
-
-	public static String unique_id = "";
 	public String getUniqueID() {
-		return unique_id;
+		return uniqueId;
 	}
 }