package lime.ui;

import haxe.io.Bytes;
import haxe.io.Path;
import lime._internal.backend.native.NativeCFFI;
import lime.app.Event;
import lime.graphics.Image;
import lime.system.BackgroundWorker;
import lime.utils.ArrayBuffer;
import lime.utils.Resource;
#if hl
import hl.Bytes as HLBytes;
import hl.NativeArray;
#end
#if sys
import sys.io.File;
#end
#if (js && html5)
import js.html.Blob;
#end

/**
	Simple file dialog used for asking user where to save a file, or select files to open.

	Example usage:
	```haxe
	var fileDialog = new FileDialog();

	fileDialog.onCancel.add( () -> trace("Canceled.") );

	fileDialog.onSave.add( path -> trace("File saved in " + path) );

	fileDialog.onOpen.add( res -> trace("Size of the file = " + (res:haxe.io.Bytes).length) );

	if ( fileDialog.open("jpg", null, "Load file") )
		trace("File dialog opened, waiting for selection...");
	else
		trace("This dialog is unsupported.");
	```

	Availability note: most file dialog operations are only available on desktop targets, though
	`save()` is also available in HTML5.
**/
#if !lime_debug
@:fileXml('tags="haxe,release"')
@:noDebug
#end
@:access(lime._internal.backend.native.NativeCFFI)
@:access(lime.graphics.Image)
class FileDialog
{
	/**
		Triggers when the user clicks "Cancel" during any operation, or when a function is unsupported
		(such as `open()` on HTML5).
	**/
	public var onCancel = new Event<Void->Void>();

	/**
		Triggers when `open()` is successful. The `lime.utils.Resource` contains the file's data, and can
		be implicitly cast to `haxe.io.Bytes`.
	**/
	public var onOpen = new Event<Resource->Void>();

	/**
		Triggers when `open()` is successful. The `lime.utils.Resource` contains the file's data, and can
		be implicitly cast to `haxe.io.Bytes`, the String is the path to the file.
	**/
	public var onOpenFile = new Event<(Resource, String)->Void>(); // Added by @NeeEoo

	/**
		Triggers when `save()` is successful. The `String` is the path to the saved file.
	**/
	public var onSave = new Event<String->Void>();

	/**
		Triggers when `browse()` is successful and `type` is anything other than
		`FileDialogType.OPEN_MULTIPLE`. The `String` is the path to the selected file.
	**/
	public var onSelect = new Event<String->Void>();

	/**
		Triggers when `browse()` is successful and `type` is `FileDialogType.OPEN_MULTIPLE`. The
		`Array<String>` contains all selected file paths.
	**/
	public var onSelectMultiple = new Event<Array<String>->Void>();

	public function new() {}

	/**
		Opens a file selection dialog. If successful, either `onSelect` or `onSelectMultiple` will trigger
		with the result(s).

		This function only works on desktop targets, and will return `false` otherwise.
		@param type 		Type of the file dialog: `OPEN`, `SAVE`, `OPEN_DIRECTORY` or `OPEN_MULTIPLE`.
		@param filter 		A filter to use when browsing. Asterisks are treated as wildcards. For example,
		`"*.jpg"` will match any file ending in `.jpg`.
		@param defaultPath 	The directory in which to start browsing and/or the default filename to
		suggest. Defaults to `Sys.getCwd()`, with no default filename.
		@param title 		The title to give the dialog window.
		@return Whether `browse()` is supported on this target.
	**/
	public function browse(type:FileDialogType = null, filter:String = null, defaultPath:String = null, title:String = null):Bool
	{
		if (type == null) type = FileDialogType.OPEN;

		#if desktop
		var worker = new BackgroundWorker();

		worker.doWork.add(function(_)
		{
			switch (type)
			{
				case OPEN:
					#if linux
					if (title == null) title = "Open File";
					#end

					var path = null;
					#if (!macro && lime_cffi)
					#if hl
					var bytes = NativeCFFI.lime_file_dialog_open_file(title, filter, defaultPath);
					if (bytes != null)
					{
						path = @:privateAccess String.fromUTF8(cast bytes);
					}
					#else
					path = NativeCFFI.lime_file_dialog_open_file(title, filter, defaultPath);
					#end
					#end

					worker.sendComplete(path);

				case OPEN_MULTIPLE:
					#if linux
					if (title == null) title = "Open Files";
					#end

					var paths = null;
					#if (!macro && lime_cffi)
					#if hl
					var bytes:NativeArray<HLBytes> = cast NativeCFFI.lime_file_dialog_open_files(title, filter, defaultPath);
					if (bytes != null)
					{
						paths = [];
						for (i in 0...bytes.length)
						{
							paths[i] = @:privateAccess String.fromUTF8(bytes[i]);
						}
					}
					#else
					paths = NativeCFFI.lime_file_dialog_open_files(title, filter, defaultPath);
					#end
					#end

					worker.sendComplete(paths);

				case OPEN_DIRECTORY:
					#if linux
					if (title == null) title = "Open Directory";
					#end

					var path = null;
					#if (!macro && lime_cffi)
					#if hl
					var bytes = NativeCFFI.lime_file_dialog_open_directory(title, filter, defaultPath);
					if (bytes != null)
					{
						path = @:privateAccess String.fromUTF8(cast bytes);
					}
					#else
					path = NativeCFFI.lime_file_dialog_open_directory(title, filter, defaultPath);
					#end
					#end

					worker.sendComplete(path);

				case SAVE:
					#if linux
					if (title == null) title = "Save File";
					#end

					var path = null;
					#if (!macro && lime_cffi)
					#if hl
					var bytes = NativeCFFI.lime_file_dialog_save_file(title, filter, defaultPath);
					if (bytes != null)
					{
						path = @:privateAccess String.fromUTF8(cast bytes);
					}
					#else
					path = NativeCFFI.lime_file_dialog_save_file(title, filter, defaultPath);
					#end
					#end

					worker.sendComplete(path);
			}
		});

		worker.onComplete.add(function(result)
		{
			switch (type)
			{
				case OPEN, OPEN_DIRECTORY, SAVE:
					var path:String = cast result;

					if (path != null)
					{
						// Makes sure the filename ends with extension
						if (type == SAVE && filter != null && path.indexOf(".") == -1)
						{
							path += "." + filter;
						}

						onSelect.dispatch(path);
					}
					else
					{
						onCancel.dispatch();
					}

				case OPEN_MULTIPLE:
					var paths:Array<String> = cast result;

					if (paths != null && paths.length > 0)
					{
						onSelectMultiple.dispatch(paths);
					}
					else
					{
						onCancel.dispatch();
					}
			}
		});

		worker.run();

		return true;
		#else
		onCancel.dispatch();
		return false;
		#end
	}

	/**
		Shows an open file dialog. If successful, `onOpen` will trigger with the file contents.

		This function only works on desktop targets, and will return `false` otherwise.
		@param filter 		A filter to use when browsing. Asterisks are treated as wildcards. For example,
		`"*.jpg"` will match any file ending in `.jpg`.
		@param defaultPath 	The directory in which to start browsing and/or the default filename to
		suggest. Defaults to `Sys.getCwd()`, with no default filename.
		@param title 		The title to give the dialog window.
		@return Whether `open()` is supported on this target.
	**/
	public function open(filter:String = null, defaultPath:String = null, title:String = null):Bool
	{
		#if (desktop && sys)
		var worker = new BackgroundWorker();

		worker.doWork.add(function(_)
		{
			#if linux
			if (title == null) title = "Open File";
			#end

			var path = null;
			#if (!macro && lime_cffi)
			#if hl
			var bytes = NativeCFFI.lime_file_dialog_open_file(title, filter, defaultPath);
			if (bytes != null) path = @:privateAccess String.fromUTF8(cast bytes);
			#else
			path = NativeCFFI.lime_file_dialog_open_file(title, filter, defaultPath);
			#end
			#end

			worker.sendComplete(path);
		});

		worker.onComplete.add(function(path:String)
		{
			if (path != null)
			{
				try
				{
					var data = File.getBytes(path);
					onOpen.dispatch(data);
					onOpenFile.dispatch(data, path); // Added by @NeeEoo
					return;
				}
				catch (e:Dynamic) {}
			}

			onCancel.dispatch();
		});

		worker.run();

		return true;
		#else
		onCancel.dispatch();
		return false;
		#end
	}

	/**
		Shows an open file dialog. If successful, `onSave` will trigger with the selected path.

		This function only works on desktop and HMTL5 targets, and will return `false` otherwise.
		@param data 		The file contents, in `haxe.io.Bytes` format. (Implicit casting possible.)
		@param filter 		A filter to use when browsing. Asterisks are treated as wildcards. For example,
		`"*.jpg"` will match any file ending in `.jpg`. Used only if targeting deskop.
		@param defaultPath 	The directory in which to start browsing and/or the default filename to
		suggest. When targeting destkop, this defaults to `Sys.getCwd()` with no default filename. When targeting
		HTML5, this defaults to the browser's download directory, with a default filename based on the MIME type.
		@param title 		The title to give the dialog window.
		@param type 		The default MIME type of the file, in case the type can't be determined from the
		file data. Used only if targeting HTML5.
		@return Whether `save()` is supported on this target.
	**/
	public function save(data:Resource, filter:String = null, defaultPath:String = null, title:String = null, type:String = "application/octet-stream"):Bool
	{
		if (data == null)
		{
			onCancel.dispatch();
			return false;
		}

		#if (desktop && sys)
		var worker = new BackgroundWorker();

		worker.doWork.add(function(_)
		{
			#if linux
			if (title == null) title = "Save File";
			#end

			var path = null;
			#if (!macro && lime_cffi)
			#if hl
			var bytes = NativeCFFI.lime_file_dialog_save_file(title, filter, defaultPath);
			path = @:privateAccess String.fromUTF8(cast bytes);
			#else
			path = NativeCFFI.lime_file_dialog_save_file(title, filter, defaultPath);
			#end
			#end

			worker.sendComplete(path);
		});

		worker.onComplete.add(function(path:String)
		{
			if (path != null)
			{
				try
				{
					File.saveBytes(path, data);
					onSave.dispatch(path);
					return;
				}
				catch (e:Dynamic) {}
			}

			onCancel.dispatch();
		});

		worker.run();

		return true;
		#elseif (js && html5)
		// TODO: Cleaner API for mimeType detection

		var defaultExtension = "";

		if (Image.__isPNG(data))
		{
			type = "image/png";
			defaultExtension = ".png";
		}
		else if (Image.__isJPG(data))
		{
			type = "image/jpeg";
			defaultExtension = ".jpg";
		}
		else if (Image.__isGIF(data))
		{
			type = "image/gif";
			defaultExtension = ".gif";
		}
		else if (Image.__isWebP(data))
		{
			type = "image/webp";
			defaultExtension = ".webp";
		}

		var path = defaultPath != null ? Path.withoutDirectory(defaultPath) : "download" + defaultExtension;
		var buffer = (data : Bytes).getData();
		buffer = buffer.slice(0, (data : Bytes).length);

		#if commonjs
		untyped #if haxe4 js.Syntax.code #else __js__ #end ("require ('file-saver')")(new Blob([buffer], {type: type}), path, true);
		#else
		untyped window.saveAs(new Blob([buffer], {type: type}), path, true);
		#end
		onSave.dispatch(path);
		return true;
		#else
		onCancel.dispatch();
		return false;
		#end
	}
}