use sdl2::{

    keyboard::Scancode,

    event::EventType,

    surface::Surface,

    pixels::{

        PixelFormatEnum, Color

    }

};

use integral_geometry::{Point, Size, Rect, Line};

use rand::{

    thread_rng, RngCore, Rng,

    distributions::uniform::SampleUniform

};

use landgen::{

    template_based::TemplatedLandGenerator,

    outline_template::OutlineTemplate,

    LandGenerator,

    LandGenerationParameters

};

use land2d::Land2D;

use lfprng::LaggedFibonacciPRNG;

struct LandSource<T> {

    rnd: LaggedFibonacciPRNG,

    generator: T

}

impl <T: LandGenerator> LandSource<T> {

    fn new(generator: T) -> Self {

        let mut init = [0u8; 64];

        thread_rng().fill_bytes(&mut init);

        LandSource {

            rnd: LaggedFibonacciPRNG::new(&init),

            generator

        }

    }

    fn next(&mut self, parameters: LandGenerationParameters<u32>) -> Land2D<u32> {

        self.generator.generate_land(&parameters, &mut self.rnd)

    }

}

fn fill_pixels(pixels: &mut [u8], land: &Land2D<u32>) {

    for (surf_row, land_row) in pixels.chunks_mut(land.width() * 4).zip(land.rows()) {

        for (surf_pixel, land_pixel) in surf_row.chunks_mut(4).zip(land_row) {

            if let [b, g, r, a] = surf_pixel {

                *a = 255; *r = *land_pixel as u8;

            }

        }

    }

}

fn fill_texture(surface: &mut Surface, land: &Land2D<u32>) {

    if surface.must_lock() {

        surface.with_lock_mut(|data| fill_pixels(data, land));

    } else {

        surface.without_lock_mut().map(|data| fill_pixels(data, land));

    }

}

fn rnd<T: Default + SampleUniform + Ord>(max: T) -> T {

    thread_rng().gen_range(T::default(), max)

}

const WINDOW_WIDTH: u32 = 800;

const WINDOW_HEIGHT: u32 = 600;

const WINDOW_SIZE: Size = Size {width: WINDOW_WIDTH as usize, height: WINDOW_HEIGHT as usize};

const PLAY_WIDTH: u32 = 3072;

const PLAY_HEIGHT: u32 = 1424;

const PLAY_SIZE: Size = Size {width: PLAY_WIDTH as usize, height: PLAY_HEIGHT as usize};

const LAND_WIDTH: u32 = 4096;

const LAND_HEIGHT: u32 = 2048;

const LAND_SIZE: Size = Size {width: LAND_WIDTH as usize, height: LAND_HEIGHT as usize};

fn point() -> Point {

    Point::new(rnd(LAND_WIDTH as i32), rnd(LAND_HEIGHT as i32))

}

fn rect() -> Rect {

    Rect::new(rnd(LAND_WIDTH as i32), rnd(LAND_HEIGHT as i32), rnd(120) + 8, rnd(120) + 8)

}

fn land_rect() -> Rect {

    Rect::at_origin(PLAY_SIZE)

}

fn basic_template() -> OutlineTemplate {

    OutlineTemplate::new(PLAY_SIZE)

        .with_fill_points(vec![land_rect().center()])

        .add_island(&land_rect().split_at(land_rect().center()))

}

macro_rules! pseudo_yaml {

    [$({x: $x: tt, y: $y: tt, w: $w: tt, h: $h: tt}),*] => {

        [$(Rect::new($x, $y, $w, $h)),*]

    }

}

fn test_template() -> OutlineTemplate {

    let island = pseudo_yaml![

        {x: 810, y: 1424, w: 1, h: 1},

        {x: 560, y: 1160, w: 130, h: 170},

        {x: 742, y: 1106, w: 316, h: 150},

        {x: 638, y: 786, w: 270, h: 180},

        {x: 646, y: 576, w: 242, h: 156},

        {x: 952, y: 528, w: 610, h: 300},

        {x: 1150, y: 868, w: 352, h: 324},

        {x: 1050, y: 1424, w: 500, h: 1},

        {x: 1650, y: 1500, w: 1, h: 1},

        {x: 1890, y: 1424, w: 1, h: 1},

        {x: 1852, y: 1304, w: 74, h: 12},

        {x: 1648, y: 975, w: 68, h: 425},

        {x: 1826, y: 992, w: 140, h: 142},

        {x: 1710, y: 592, w: 150, h: 350},

        {x: 1988, y: 594, w: 148, h: 242},

        {x: 2018, y: 872, w: 276, h: 314},

        {x: 2110, y: 1250, w: 130, h: 86},

        {x: 2134, y: 1424, w: 1, h: 1}

    ];

    OutlineTemplate::new(PLAY_SIZE)

        .add_island(&island)

        .add_fill_points(&[Point::new(1023, 0)])

}

fn init_source() -> LandSource<TemplatedLandGenerator> {

    let template = test_template();

    let generator = TemplatedLandGenerator::new(template);

    LandSource::new(generator)

}

fn draw_center_mark(land: &mut Land2D<u32>) {

    for i in 0..32 {

        land.draw_thick_line(Line::new(Point::new(LAND_WIDTH as i32 / 2, 0),

                                       Point::new(LAND_WIDTH as i32 / 2, LAND_HEIGHT as i32)), 10, 128);

        land.draw_thick_line(Line::new(Point::new(0, LAND_HEIGHT as i32 / 2),

                                       Point::new(LAND_WIDTH as i32, LAND_HEIGHT as i32 / 2)), 10, 128);

        land.fill_circle(Point::new(LAND_WIDTH as i32, LAND_HEIGHT as i32) / 2, 60, 128);

    }

}

fn draw_random_lines(land: &mut Land2D<u32>) {

    for i in 0..32 {

        land.draw_thick_line(Line::new(point(), point()), rnd(5), 128);

        land.fill_circle(point(), rnd(60), 128);

    }

}

fn main() {

    let sdl = sdl2::init().unwrap();

    let _image = sdl2::image::init(sdl2::image::INIT_PNG).unwrap();

    let events = sdl.event().unwrap();

    let mut pump = sdl.event_pump().unwrap();

    let video = sdl.video().unwrap();

    let window = video.window("Theme Editor", WINDOW_WIDTH, WINDOW_HEIGHT)

        .position_centered()

        .build().unwrap();

    let mut source = init_source();

    let mut land = source.next(

        LandGenerationParameters::new(0, u32::max_value(), 1, false, false));

    draw_center_mark(&mut land);

    let mut land_surf = Surface::new(LAND_WIDTH, LAND_HEIGHT, PixelFormatEnum::ARGB8888).unwrap();

    fill_texture(&mut land_surf, &land);

    let mut win_surf = window.surface(&pump).unwrap();

    let dest_rect = win_surf.rect();

    land_surf.blit_scaled(land_surf.rect(), &mut win_surf, dest_rect).unwrap();

    win_surf.update_window();

    'pool: loop {

        use sdl2::event::Event::*;

        pump.pump_events();

        while let Some(event) = pump.poll_event() {

            match event {

                Quit{ .. } => break 'pool,

                _ => ()

            }

        }

    }

}