class MyWindow: Gtk.ApplicationWindow {

	/* MyWindow instance variables. */

	GLib.File? file;

	Gtk.TextBuffer buffer;

	Gtk.TextView textview;

	Gtk.ScrolledWindow scrolled_window;

	/* Create ActionEntries. */

	const ActionEntry[] actions = {

		{ "new", new_cb },

		{ "open", open_cb },

		{ "save", save_cb },

		{ "save-as", save_as_cb }

	};

	/* Constructor creates MyWindow, and add the scrolled_window. */

	internal MyWindow (MyApplication app) {

		Object (application: app, title: "FileChooserDialog Example");

		this.set_default_size (400, 400);

		/* Add the ActionEntries to MyWindow. */

		this.add_action_entries (actions, this);

		buffer = new Gtk.TextBuffer (null); //stores text to be displayed

		textview = new Gtk.TextView.with_buffer (buffer); //displays TextBuffer

		textview.set_wrap_mode (Gtk.WrapMode.WORD); //sets line wrapping

		scrolled_window = new Gtk.ScrolledWindow (null, null);

		scrolled_window.set_policy (Gtk.PolicyType.AUTOMATIC,

		                            Gtk.PolicyType.AUTOMATIC);

		scrolled_window.add (textview);

		scrolled_window.set_border_width (5);

        this.add (scrolled_window);

		this.show_all ();

	}

	void new_cb (SimpleAction action, Variant? parameter) {

		file = null;

		buffer.set_text ("");

		print ("New file created\n");

	}

	/* Create FileChooserDialog in OPEN mode. */

	void open_cb (SimpleAction action, Variant? parameter) {

		var open_dialog = new Gtk.FileChooserDialog ("Pick a file",

		                                             this as Gtk.Window,

		                                             Gtk.FileChooserAction.OPEN,

		                                             Gtk.Stock.CANCEL,

		                                             Gtk.ResponseType.CANCEL,

		                                             Gtk.Stock.OPEN,

		                                             Gtk.ResponseType.ACCEPT);

		open_dialog.local_only = false; //allow for uri

		open_dialog.set_modal (true);

		open_dialog.response.connect (open_response_cb);

		open_dialog.show ();

	}

	/* Either open the file and load the file contents or cancel. */

	void open_response_cb (Gtk.Dialog dialog, int response_id) {

		var open_dialog = dialog as Gtk.FileChooserDialog;

		switch (response_id) {

			case Gtk.ResponseType.ACCEPT: //open the file

				file = open_dialog.get_file();

				uint8[] file_contents;

				try {

					file.load_contents (null, out file_contents, null);

				}

				catch (GLib.Error err) { //handle the exception

					error ("%s\n", err.message);

				}

				/* Set the buffer text to be the contents of the file. */

				buffer.set_text ((string) file_contents,

				                 file_contents.length);

				print ("opened: %s\n", (open_dialog.get_filename ()));

				break;

			case Gtk.ResponseType.CANCEL:

				print ("cancelled: FileChooserAction.OPEN\n");

				break;

		}

		dialog.destroy ();

	}

	/* Create FileChooserDialog in SAVE mode. */

	void save_as_cb (SimpleAction action, Variant? parameter) {

		var save_dialog = new Gtk.FileChooserDialog ("Pick a file",

		                                             this as Gtk.Window,

		                                             Gtk.FileChooserAction.SAVE,

		                                             Gtk.Stock.CANCEL,

		                                             Gtk.ResponseType.CANCEL,

		                                             Gtk.Stock.SAVE,

		                                             Gtk.ResponseType.ACCEPT);

		save_dialog.set_do_overwrite_confirmation (true);

		save_dialog.set_modal (true);

		if (file != null) {

			try {

				(save_dialog as Gtk.FileChooser).set_file (file);

			}

			catch (GLib.Error error) {

				print ("%s\n", error.message);

			}

		}

		save_dialog.response.connect (save_as_response_cb);

		save_dialog.show ();

	}

	void save_as_response_cb (Gtk.Dialog dialog, int response_id) {

		var save_dialog = dialog as Gtk.FileChooserDialog;

		switch (response_id) {

			case Gtk.ResponseType.ACCEPT:

				file = save_dialog.get_file();

				this.save_to_file ();

				break;

			default:

				break;

		}

			dialog.destroy ();

	}

	/* Save the existing contents to the file.

	 * If file does not exist, call save_as_cb.

	 */

	void save_cb (SimpleAction action, Variant? parameter) {

		if (file != null) {

			this.save_to_file ();

		}

		else {

			save_as_cb (action, parameter);

		}

	}

	void save_to_file (){

		Gtk.TextIter start;

		Gtk.TextIter end;

		buffer.get_bounds (out start, out end);

		string current_contents = buffer.get_text (start, end, false);

		try {

				file.replace_contents (current_contents.data, null, false,

				                       GLib.FileCreateFlags.NONE, null, null);

				print ("saved: %s\n", file.get_path ());

		}

		catch (GLib.Error err) {

			error ("%s\n", err.message);

		}

	}

}

/* This is the application */

class MyApplication: Gtk.Application {

	protected override void activate () {

		new MyWindow (this).show_all;

	}

	const ActionEntry[] actions = {

		{ "quit", quit_cb }

	};

	void quit_cb (SimpleAction action, Variant? parameter) {

		this.quit ();

	}

	protected override void startup () {

		base.startup ();

		/* Setup actions */

		this.add_action_entries (actions, this);

		/* Setup menus */

		var builder = new Gtk.Builder ();

		try {

			builder.add_from_file ("filechooserdialog.ui");

		} catch (GLib.Error err) {

			error ("Unable to load file: %s\n", err.message);

		}

		this.app_menu = builder.get_object ("appmenu") as MenuModel;

	}

}

/* main creates and runs the application. */

public int main (string[] args) {

	return new MyApplication ().run (args);

}