1 files changed, 112 insertions, 0 deletions
diff --git a/src/photos/PhotoFileAdapter.vala b/src/photos/PhotoFileAdapter.vala
new file mode 100644
index 0000000..38b00ea
--- /dev/null
+++ b/src/photos/PhotoFileAdapter.vala
@@ -0,0 +1,112 @@
+/* Copyright 2010-2014 Yorba Foundation
+ *
+ * This software is licensed under the GNU Lesser General Public License
+ * (version 2.1 or later).  See the COPYING file in this distribution.
+ */
+
+//
+// PhotoFileAdapter
+//
+// PhotoFileAdapter (and its immediate children, PhotoFileReader and PhotoFileWriter) are drivers
+// hiding details of reading and writing image files and their metadata.  They should keep
+// minimal state beyond the filename, if any stat at all.  In particular, they should avoid caching
+// values, especially the readers, as writers may be created at any time and invalidate that
+// information, unless the readers monitor the file for these changes.
+//
+// PhotoFileAdapters should be entirely thread-safe.  They are not, however, responsible for
+// atomicity on the filesystem.
+//
+
+public abstract class PhotoFileAdapter {
+    private string filepath;
+    private PhotoFileFormat file_format;
+    private File file = null;
+    
+    public PhotoFileAdapter(string filepath, PhotoFileFormat file_format) {
+        this.filepath = filepath;
+        this.file_format = file_format;
+    }
+    
+    public bool file_exists() {
+        return FileUtils.test(filepath, FileTest.IS_REGULAR);
+    }
+    
+    public string get_filepath() {
+        return filepath;
+    }
+    
+    public File get_file() {
+        File result;
+        lock (file) {
+            if (file == null)
+                file = File.new_for_path(filepath);
+            
+            result = file;
+        }
+        
+        return result;
+    }
+    
+    public PhotoFileFormat get_file_format() {
+        return file_format;
+    }
+}
+
+//
+// PhotoFileReader
+//
+
+public abstract class PhotoFileReader : PhotoFileAdapter {
+    protected PhotoFileReader(string filepath, PhotoFileFormat file_format) {
+        base (filepath, file_format);
+    }
+    
+    public PhotoFileWriter create_writer() throws PhotoFormatError {
+        return get_file_format().create_writer(get_filepath());
+    }
+    
+    public PhotoFileMetadataWriter create_metadata_writer() throws PhotoFormatError {
+        return get_file_format().create_metadata_writer(get_filepath());
+    }
+    
+    public abstract PhotoMetadata read_metadata() throws Error;
+    
+    public abstract Gdk.Pixbuf unscaled_read() throws Error;
+    
+    public virtual Gdk.Pixbuf scaled_read(Dimensions full, Dimensions scaled) throws Error {
+        return resize_pixbuf(unscaled_read(), scaled, Gdk.InterpType.BILINEAR);
+    }
+}
+
+//
+// PhotoFileWriter
+//
+
+public abstract class PhotoFileWriter : PhotoFileAdapter {
+    protected PhotoFileWriter(string filepath, PhotoFileFormat file_format) {
+        base (filepath, file_format);
+    }
+    
+    public PhotoFileReader create_reader() {
+        return get_file_format().create_reader(get_filepath());
+    }
+    
+    public abstract void write(Gdk.Pixbuf pixbuf, Jpeg.Quality quality) throws Error;
+}
+
+//
+// PhotoFileMetadataWriter
+//
+
+public abstract class PhotoFileMetadataWriter : PhotoFileAdapter {
+    protected PhotoFileMetadataWriter(string filepath, PhotoFileFormat file_format) {
+        base (filepath, file_format);
+    }
+    
+    public PhotoFileReader create_reader() {
+        return get_file_format().create_reader(get_filepath());
+    }
+    
+    public abstract void write_metadata(PhotoMetadata metadata) throws Error;
+}
+