Funkin/source/funkin/play/song/SongSerializer.hx

package funkin.play.song;

import funkin.play.song.SongData.SongChartData;
import funkin.play.song.SongData.SongMetadata;
import funkin.util.SerializerUtil;
import lime.utils.Bytes;
import openfl.events.Event;
import openfl.events.IOErrorEvent;
import openfl.net.FileReference;

/**
 * Utilities for exporting a chart to a JSON file.
 * Primarily used for the chart editor.
 */
class SongSerializer
{
	/**
	 * Access a SongChartData JSON file from a specific path, then load it.
	 * @param	path The file path to read from.
	 */
	public static function importSongChartDataSync(path:String):SongChartData
	{
		var fileData = readFile(path);

		if (fileData == null)
			return null;

		var songChartData:SongChartData = fileData.parseJSON();

		return songChartData;
	}

	/**
	 * Access a SongMetadata JSON file from a specific path, then load it.
	 * @param	path The file path to read from.
	 */
	public static function importSongMetadataSync(path:String):SongMetadata
	{
		var fileData = readFile(path);

		if (fileData == null)
			return null;

		var songMetadata:SongMetadata = fileData.parseJSON();

		return songMetadata;
	}

	/**
	 * Prompt the user to browse for a SongChartData JSON file path, then load it.
	 * @param	callback The function to call when the file is loaded.
	 */
	public static function importSongChartDataAsync(callback:SongChartData->Void):Void
	{
		browseFileReference(function(fileReference:FileReference)
		{
			var data = fileReference.data.toString();

			if (data == null)
				return;

			var songChartData:SongChartData = data.parseJSON();

			if (songChartData != null)
				callback(songChartData);
		});
	}

	/**
	 * Prompt the user to browse for a SongMetadata JSON file path, then load it.
	 * @param	callback The function to call when the file is loaded.
	 */
	public static function importSongMetadataAsync(callback:SongMetadata->Void):Void
	{
		browseFileReference(function(fileReference:FileReference)
		{
			var data = fileReference.data.toString();

			if (data == null)
				return;

			var songMetadata:SongMetadata = data.parseJSON();

			if (songMetadata != null)
				callback(songMetadata);
		});
	}

	/**
	 * Save a SongChartData object as a JSON file to an automatically generated path.
	 * Works great on HTML5 and desktop.
	 */
	public static function exportSongChartData(data:SongChartData)
	{
		var path = 'chart.json';
		exportSongChartDataAs(path, data);
	}

	/**
	 * Save a SongMetadata object as a JSON file to an automatically generated path.
	 * Works great on HTML5 and desktop.
	 */
	public static function exportSongMetadata(data:SongMetadata)
	{
		var path = 'metadata.json';
		exportSongMetadataAs(path, data);
	}

	/**
	 * Save a SongChartData object as a JSON file to a specified path.
	 * Works great on HTML5 and desktop.
	 * 
	 * @param	path The file path to save to.
	 */
	public static function exportSongChartDataAs(path:String, data:SongChartData)
	{
		var dataString = SerializerUtil.toJSON(data);

		writeFileReference(path, dataString);
	}

	/**
	 * Save a SongMetadata object as a JSON file to a specified path.
	 * Works great on HTML5 and desktop.
	 * 
	 * @param	path The file path to save to.
	 */
	public static function exportSongMetadataAs(path:String, data:SongMetadata)
	{
		var dataString = SerializerUtil.toJSON(data);

		writeFileReference(path, dataString);
	}

	/**
	 * Read the string contents of a file.
	 * Only works on desktop platforms.
	 * @param	path The file path to read from.
	 */
	static function readFile(path:String):String
	{
		#if sys
		var fileBytes:Bytes = sys.io.File.getBytes(path);

		if (fileBytes == null)
			return null;

		return fileBytes.toString();
		#end

		trace('ERROR: readFile not implemented for this platform');
		return null;
	}

	/**
	 * Write string contents to a file.
	 * Only works on desktop platforms.
	 * @param	path The file path to read from.
	 */
	static function writeFile(path:String, data:String):Void
	{
		#if sys
		sys.io.File.saveContent(path, data);
		return;
		#end
		trace('ERROR: writeFile not implemented for this platform');
		return;
	}

	/**
	 * Browse for a file to read and execute a callback once we have a file reference.
	 * Works great on HTML5 or desktop.
	 * 
	 * @param	callback The function to call when the file is loaded.
	 */
	static function browseFileReference(callback:FileReference->Void)
	{
		var file = new FileReference();

		file.addEventListener(Event.SELECT, function(e)
		{
			var selectedFileRef:FileReference = e.target;
			trace('Selected file: ' + selectedFileRef.name);
			selectedFileRef.addEventListener(Event.COMPLETE, function(e)
			{
				var loadedFileRef:FileReference = e.target;
				trace('Loaded file: ' + loadedFileRef.name);
				callback(loadedFileRef);
			});
			selectedFileRef.load();
		});

		file.browse();
	}

	/**
	 * Prompts the user to save a file to their computer.
	 */
	static function writeFileReference(path:String, data:String)
	{
		var file = new FileReference();
		file.addEventListener(Event.COMPLETE, function(e:Event)
		{
			trace('Successfully wrote file.');
		});
		file.addEventListener(Event.CANCEL, function(e:Event)
		{
			trace('Cancelled writing file.');
		});
		file.addEventListener(IOErrorEvent.IO_ERROR, function(e:IOErrorEvent)
		{
			trace('IO error writing file.');
		});
		file.save(data, path);
	}
}