tdf#129833 android: Allow editing writable docs passed by Intent

When a document is passed by an Intent in Android
Viewer, allow editing if the Intent has flag
'Intent.FLAG_GRANT_WRITE_URI_PERMISSION' set.

Since LibreOffice operates on a temporary copy
in this case, write the content of the
temporary file back to the original URI
when saving.

This in particular allows editing documents
passed from third-party apps, e.g. opened from
Android's "Files" app or the NextCloud app.

The online-based Android app already does
something similar.

Change-Id: Icf252a95dd9a8089ca8610ccf3edfbeee2682e1a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/112767
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>
(cherry picked from commit 2df8b776e635efc5e59aaf6c8a5a7f4c218d74d0)

4 files changed, 62 insertions, 2 deletions

diff --git a/android/source/res/values-de/strings.xml b/android/source/res/values-de/strings.xml
index ff58b14babc5..64eaa844a754 100644
--- a/android/source/res/values-de/strings.xml
+++ b/android/source/res/values-de/strings.xml
@@ -96,6 +96,7 @@
     <string name="message_saved">Speichern beendet</string>
     <string name="message_saving">Dokument wird gespeichert…</string>
     <string name="message_save_incomplete">Speichern unvollständig. Gab es Änderungen?</string>
+    <string name="message_saving_failed">Speichern des Dokuments ist fehlgeschlagen.</string>
     <string name="create_new_file_success">"Neue Datei angelegt - "</string>
     <string name="create_new_file_error">Neue Datei konnte nicht angelegt weden, bitte Prüfen Sie den eingegeben Dateinamen.</string>
 
diff --git a/android/source/res/values/strings.xml b/android/source/res/values/strings.xml
index aa32497862f6..a44d81ee5faf 100644
--- a/android/source/res/values/strings.xml
+++ b/android/source/res/values/strings.xml
@@ -95,6 +95,7 @@
     <!-- Feedback messages -->
     <string name="message_saved">Save complete</string>
     <string name="message_saving">Saving the document…</string>
+    <string name="message_saving_failed">Saving the document failed.</string>
     <string name="message_save_incomplete">Save incomplete. Were there any changes?</string>
     <string name="create_new_file_success">"Created new file - "</string>
     <string name="create_new_file_error">Unable to create new file, please check entered file name.</string>
diff --git a/android/source/src/java/org/libreoffice/InvalidationHandler.java b/android/source/src/java/org/libreoffice/InvalidationHandler.java
index 32e9b56656dd..588fec9f5372 100644
--- a/android/source/src/java/org/libreoffice/InvalidationHandler.java
+++ b/android/source/src/java/org/libreoffice/InvalidationHandler.java
@@ -139,7 +139,7 @@ public class InvalidationHandler implements Document.MessageCallback, Office.Mes
             JSONObject payloadObject = new JSONObject(payload);
             if (payloadObject.getString("commandName").equals(".uno:Save")) {
                 if (payloadObject.getString("success").equals("true")) {
-                    mContext.saveFilesToCloud();
+                    mContext.saveFileToOriginalSource();
                 }
             }else if(payloadObject.getString("commandName").equals(".uno:Name") ||
                     payloadObject.getString("commandName").equals(".uno:RenamePage")){
diff --git a/android/source/src/java/org/libreoffice/LibreOfficeMainActivity.java b/android/source/src/java/org/libreoffice/LibreOfficeMainActivity.java
index b640fa404973..bf6108edc8af 100644
--- a/android/source/src/java/org/libreoffice/LibreOfficeMainActivity.java
+++ b/android/source/src/java/org/libreoffice/LibreOfficeMainActivity.java
@@ -46,9 +46,11 @@ import org.mozilla.gecko.gfx.GeckoLayerClient;
 import org.mozilla.gecko.gfx.LayerView;
 
 import java.io.File;
+import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.OutputStream;
 import java.net.URI;
 import java.nio.ByteBuffer;
 import java.nio.channels.Channels;
@@ -191,7 +193,8 @@ public class LibreOfficeMainActivity extends AppCompatActivity implements Settin
             if (getIntent().getData().getScheme().equals(ContentResolver.SCHEME_CONTENT)) {
                 if (copyFileToTemp() && mTempFile != null) {
                     mInputFile = mTempFile;
-                    mbISReadOnlyMode = true;
+                    boolean isReadOnlyDoc = (getIntent().getFlags() & Intent.FLAG_GRANT_WRITE_URI_PERMISSION) == 0;
+                    mbISReadOnlyMode = !isExperimentalMode()  || isReadOnlyDoc;
                     Log.d(LOGTAG, "SCHEME_CONTENT: getPath(): " + getIntent().getData().getPath());
 
                     String displayName = extractDisplayNameFromIntent();
@@ -355,6 +358,61 @@ public class LibreOfficeMainActivity extends AppCompatActivity implements Settin
         LOKitShell.sendEvent(new LOEvent(LOEvent.UNO_COMMAND_NOTIFY, ".uno:Save", true));
     }
 
+    public void saveFileToOriginalSource() {
+        if (documentUri != null) {
+            // case where file was opened using IDocumentProvider from within LO app
+            saveFilesToCloud();
+        } else {
+            // case where file was passed via Intent
+            if (isReadOnlyMode() || mInputFile == null || getIntent().getData() == null || !getIntent().getData().getScheme().equals(ContentResolver.SCHEME_CONTENT))
+                return;
+
+            Uri uri = getIntent().getData();
+            FileInputStream inputStream = null;
+            OutputStream outputStream = null;
+
+            try {
+                inputStream = new FileInputStream(mInputFile);
+                // OutputStream for the actual (original) location
+                outputStream = getContentResolver().openOutputStream(uri);
+
+                byte[] buffer = new byte[4096];
+                int readBytes = inputStream.read(buffer);
+                while (readBytes != -1) {
+                    outputStream.write(buffer, 0, readBytes);
+                    readBytes = inputStream.read(buffer);
+                }
+
+                runOnUiThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        Toast.makeText(LibreOfficeMainActivity.this, R.string.message_saved,
+                            Toast.LENGTH_SHORT).show();
+                    }
+                });
+                setDocumentChanged(false);
+            } catch (Exception e) {
+                runOnUiThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        Toast.makeText(LibreOfficeMainActivity.this, R.string.message_saving_failed,
+                            Toast.LENGTH_SHORT).show();
+                    }
+                });
+                e.printStackTrace();
+            } finally {
+                try {
+                    if (inputStream != null)
+                        inputStream.close();
+                    if (outputStream != null)
+                        outputStream.close();
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+    }
+
     public void saveFilesToCloud(){
         final Activity activity = LibreOfficeMainActivity.this;
         final AsyncTask<Void, Void, Void> task = new AsyncTask<Void, Void, Void>() {