Fix update date template based on date source (#2483) (#2492)

* Fix update date template based on date source

* Add javadocs

app/src/main/java/fr/free/nrw/commons/filepicker/UploadableFile.java

@@ -6,7 +6,16 @@ import android.net.Uri;
 import android.os.Parcel;
 import android.os.Parcelable;
 
+import com.drew.imaging.ImageMetadataReader;
+import com.drew.imaging.ImageProcessingException;
+import com.drew.metadata.Metadata;
+import com.drew.metadata.exif.ExifSubIFDDirectory;
+
 import java.io.File;
+import java.io.IOException;
+import java.util.Date;
+
+import javax.annotation.Nullable;
 
 import fr.free.nrw.commons.upload.FileUtils;
 
@@ -62,16 +71,32 @@ public class UploadableFile implements Parcelable {
         return 0;
     }
 
+
+    /**
+     * First try to get the file creation date from EXIF else fall back to CP
+     * @param context
+     * @return
+     */
+    @Nullable
+    public DateTimeWithSource getFileCreatedDate(Context context) {
+        DateTimeWithSource dateTimeFromExif = getDateTimeFromExif();
+        if (dateTimeFromExif == null) {
+            return getFileCreatedDateFromCP(context);
+        } else {
+            return dateTimeFromExif;
+        }
+    }
+
     /**
      * Get filePath creation date from uri from all possible content providers
      *
      * @return
      */
-    public long getFileCreatedDate(Context context) {
+    private DateTimeWithSource getFileCreatedDateFromCP(Context context) {
         try {
             Cursor cursor = context.getContentResolver().query(contentUri, null, null, null, null);
             if (cursor == null) {
-                return -1;//Could not fetch last_modified
+                return null;//Could not fetch last_modified
             }
             //Content provider contracts for opening gallery from the app and that by sharing from gallery from outside are different and we need to handle both the cases
             int lastModifiedColumnIndex = cursor.getColumnIndex("last_modified");//If gallery is opened from in app
@@ -80,18 +105,69 @@ public class UploadableFile implements Parcelable {
             }
             //If both the content providers do not give the data, lets leave it to Jesus
             if (lastModifiedColumnIndex == -1) {
-                return -1l;
+                return null;
             }
             cursor.moveToFirst();
-            return cursor.getLong(lastModifiedColumnIndex);
+            return new DateTimeWithSource(cursor.getLong(lastModifiedColumnIndex), DateTimeWithSource.CP_SOURCE);
         } catch (Exception e) {
-            return -1;////Could not fetch last_modified
+            return null;////Could not fetch last_modified
         }
     }
 
+    /**
+     * Get filePath creation date from uri from EXIF
+     *
+     * @return
+     */
+    private DateTimeWithSource getDateTimeFromExif() {
+        Metadata metadata;
+        try {
+            metadata = ImageMetadataReader.readMetadata(file);
+            ExifSubIFDDirectory directory = metadata.getFirstDirectoryOfType(ExifSubIFDDirectory.class);
+            if (directory!=null && directory.containsTag(ExifSubIFDDirectory.TAG_DATETIME_ORIGINAL)) {
+                Date date = directory.getDate(ExifSubIFDDirectory.TAG_DATETIME_ORIGINAL);
+                return new DateTimeWithSource(date, DateTimeWithSource.EXIF_SOURCE);
+            }
+        } catch (ImageProcessingException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return null;
+    }
+
     @Override
     public void writeToParcel(Parcel parcel, int i) {
         parcel.writeParcelable(contentUri, 0);
         parcel.writeSerializable(file);
     }
+
+    /**
+     * This class contains the epochDate along with the source from which it was extracted
+     */
+    public class DateTimeWithSource {
+        public static final String CP_SOURCE = "contentProvider";
+        public static final String EXIF_SOURCE = "exif";
+
+        private final long epochDate;
+        private final String source;
+
+        public DateTimeWithSource(long epochDate, String source) {
+            this.epochDate = epochDate;
+            this.source = source;
+        }
+
+        public DateTimeWithSource(Date date, String source) {
+            this.epochDate = date.getTime();
+            this.source = source;
+        }
+
+        public long getEpochDate() {
+            return epochDate;
+        }
+
+        public String getSource() {
+            return source;
+        }
+    }
 }