use common::{Dimension, Point, Intersection};
use core::app::{AppState, StateChange};
use core::controller::ControllerManager;
use core::level::Grid;
use core::render::Renderer;
use {point, dimen};
use sdl2::event::Event;
use sprites::SpriteManager;
use time::{Duration, Instant};

pub struct TestState {
    start: Instant,
    mouse: Point<i32>,
}

impl TestState {
    pub fn new() -> TestState {
        TestState {
	    start: Instant::now(),
	    mouse: point!(0, 0),
        }
    }

    fn draw_intersecting_lines(&self, renderer: &mut Renderer, p1: (i32, i32), p2: (i32, i32), p3: (i32, i32), p4: (i32, i32)) {
	let color = match Intersection::lines(
	    point!(p1.0 as f64, p1.1 as f64),
	    point!(p2.0 as f64, p2.1 as f64),
	    point!(p3.0 as f64, p3.1 as f64),
	    point!(p4.0 as f64, p4.1 as f64)
	) {
	    Intersection::Point(p) => {
		renderer.circle((p.x as i16, p.y as i16), 3, (255, 255, 0));
		(0, 255, 0)
	    }
	    Intersection::None => (255, 0, 0)
	};
	renderer.draw_line(p1, p2, color);
	renderer.draw_line(p3, p4, color);
    }
}

impl AppState for TestState {
    fn enter(&mut self, _ctrl_man: &ControllerManager) {}

    fn update(&mut self, _dt: Duration) -> Option<StateChange> {
	None
    }

    fn render(&mut self, renderer: &mut Renderer, _sprites: &SpriteManager) {
	// crossing
	self.draw_intersecting_lines(renderer, (0, 0), (20, 20), (20, 0), (0, 20));
	self.draw_intersecting_lines(renderer, (30, 10), (50, 10), (40, 0), (40, 20));

	// just touching
	self.draw_intersecting_lines(renderer, (70, 0), (70, 10), (60, 10), (80, 10));
	self.draw_intersecting_lines(renderer, (90, 0), (100, 10), (90, 20), (110, 0));
	self.draw_intersecting_lines(renderer, (120, 0), (140, 20), (120, 20), (130, 10));
	self.draw_intersecting_lines(renderer, (170, 10), (160, 10), (160, 0), (160, 20));

	// not touching
	self.draw_intersecting_lines(renderer, (190, 0), (210, 20), (195, 20), (200, 15));

	let a = self.start.elapsed().as_seconds_f64().sin() * std::f64::consts::FRAC_PI_2;
	let (ax, ay) = ((a.cos() * 200.0) as i32, (a.sin() * 200.0) as i32);
	self.draw_intersecting_lines(renderer, (10, 400), (10 + ax, 400 + ay), (30, 200), (30, 600));

	let x = (self.start.elapsed().as_seconds_f64().cos() * 60.0) as i32;
	let y = (self.start.elapsed().as_seconds_f64().sin() * 60.0) as i32;
	let x2 = ((self.start.elapsed().as_seconds_f64() + std::f64::consts::FRAC_PI_4).cos() * 60.0) as i32;
	let y2 = ((self.start.elapsed().as_seconds_f64() + std::f64::consts::FRAC_PI_4).sin() * 60.0) as i32;
	self.draw_intersecting_lines(renderer, (100 + x, 100 + y), (150 + x, 150 + y), (100 + x2, 150 + y2), (150 + x2, 100 + y2));
	self.draw_intersecting_lines(renderer, (250 + x, 85 + y), (250 + x, 165 + y), (210 + x2, 125 + y2), (290 + x2, 125 + y2));

	let grid = Grid {
	    size: dimen!(10, 10),
	    scale: dimen!(30.0, 30.0),
	    cells: vec!(vec!(false; 10); 10),
	};

	let offset = point!(200, 200);
	let size = grid.scale;
	for x in 0..grid.size.width {
	    for y in 0..grid.size.height {
		let col = (32 + 32 * ((x + y) % 2)) as u8;
		renderer.canvas().set_draw_color((col, col, col));
		renderer.canvas().fill_rect(sdl2::rect::Rect::new(
		    offset.x + x as i32 * size.width as i32,
		    offset.y + y as i32 * size.height as i32,
		    size.width as u32,
		    size.height as u32)).unwrap();
	    }
	}

	let offsetf = point!(offset.x as f64, offset.y as f64);
//	let p1 = point!(23.0, 16.0);
	let p1 = point!(300.0 / 2.0, 300.0 / 2.0);
	let p2 = {
	    //let p = point!(78.0*3.0, 54.0*3.0);
	    let p = self.mouse - offset;
	    point!(p.x as f64, p.y as f64)
	};
	for p in grid.grid_coordinates_on_line(p1, p2) {
	    renderer.canvas().set_draw_color((0, 96, 0));
	    renderer.canvas().fill_rect(sdl2::rect::Rect::new(
		offset.x + p.x as i32 * size.width as i32,
		offset.y + p.y as i32 * size.height as i32,
		size.width as u32,
		size.height as u32)).unwrap();
	}
	let p1 = p1 + offsetf;
	let p2 = self.mouse;//p2 + offsetf;
	renderer.draw_line((p1.x as i32, p1.y as i32), (p2.x as i32, p2.y as i32), (255, 255, 0));
    }

    fn leave(&mut self) {
    }

    fn handle_event(&mut self, _event: Event) -> Option<StateChange> {
	match _event {
	    Event::MouseMotion { x, y, .. } => self.mouse = point!(x, y),
	    _ => {}
	}
	None
    }
}