extern crate gtk;
extern crate chessground;
#[macro_use]
extern crate relm;
extern crate relm_attributes;
#[macro_use]
extern crate relm_derive;
extern crate shakmaty;
extern crate rsvg;

use gtk::prelude::*;
use gtk::GtkWindowExt;
use relm::Widget;
use relm_attributes::widget;

use shakmaty::{Square, Chess, Role, Position, Move};
use chessground::{Ground, UserMove, SetPos, Pos};

use rsvg::{Handle};
use rsvg::HandleExt;

use self::Msg::*;

#[derive(Msg)]
pub enum Msg {
    Quit,
    PieceMoved{orig: Square, dest: Square, promotion: Option<Role>},
}

#[derive(Default)]
pub struct Model {
    position: Chess,
}

impl Model
{
    fn play(&mut self, move_to_play: &Move) -> &mut Model {
        let play_result = self.position.play(move_to_play);
        match play_result {
            Ok(position) => self.position = position,
            _ => {}
        }
        self
    }
}


#[widget]
impl Widget for Win {
    fn model() -> Model {
        Model ::default()
    }

    fn update(&mut self, event: Msg) {
        match event {
            Quit => gtk::main_quit(),
            PieceMoved{orig, dest, promotion} => self.handle_move(orig, dest, promotion),
        }
    }

    fn handle_move(&mut self, orig: Square, dest: Square, promotion: Option<Role>)
    {
        let legals = self.model.position.legals();
        let move_to_play = legals.iter().find(|m| {
            m.from() == Some(orig) && m.to() == dest &&
            m.promotion() == promotion
        });

        match move_to_play {
            Some(move_to_play) => {
                &mut self.model.play(move_to_play);
                self.ground.emit(SetPos(Pos::new(&self.model.position)));
            },
            _ => {}
        };
    }

    view! {
        gtk::Window {
            title: "Chessground",
            property_default_width: 600,
            property_default_height: 600,
            icon: &Handle::new_from_str(include_str!("wQ.svg"))
                .expect("Could not find icon !")
                .get_pixbuf()
                .expect("No pixbuf for the icon !"),
            #[name="ground"]
            Ground {
                UserMove(orig, dest, promotion) => PieceMoved{orig, dest, promotion},
            },
            delete_event(_, _) => (Quit, Inhibit(false)),
        }
    }
}

fn main() {
    Win::run(()).expect("Failed to initialize gtk !");
}