use ::rltk::RandomNumberGenerator;

use super::{BuilderChain, BuilderMap, InitialMapBuilder};
use crate::map_builders::area_starting_points::AreaStartingPosition;
use crate::map_builders::distant_exit::DistantExit;
use crate::TileType;

pub fn town_builder(
    new_depth: i32,
    rng: &mut RandomNumberGenerator,
    width: i32,
    height: i32,
) -> BuilderChain {
    let (start_x, start_y) = super::random_start_position(rng);
    let mut chain = BuilderChain::new(new_depth, width, height);

    chain
        .start_with(TownBuilder::new())
        .with(AreaStartingPosition::new(start_x, start_y))
        .with(DistantExit::new());

    chain
}

pub struct TownBuilder {}

impl InitialMapBuilder for TownBuilder {
    #[allow(dead_code)]
    fn build_map(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
        self.build_rooms(rng, build_data);
    }
}

impl TownBuilder {
    pub fn new() -> Box<TownBuilder> {
        Box::new(TownBuilder {})
    }

    pub fn build_rooms(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
        self.grass_layer(build_data);
        self.water_and_piers(rng, build_data);

        // Make visible for screenshot
        for t in build_data.map.visible_tiles.iter_mut() {
            *t = true;
        }
        build_data.take_snapshot();
    }

    fn grass_layer(&mut self, build_data: &mut BuilderMap) {
        // We'll start with a nice layer of grass
        for t in build_data.map.tiles.iter_mut() {
            *t = TileType::Grass
        }
        build_data.take_snapshot();
    }

    fn water_and_piers(&mut self, rng: &mut RandomNumberGenerator, build_data: &mut BuilderMap) {
        let mut n = (rng.roll_dice(1, 65535) as f32) / 65535_f32;
        let mut water_width: Vec<i32> = Vec::new();

        for y in 0..build_data.height {
            let n_water = (f32::sin(n) * 10.0) as i32 + 14 + rng.roll_dice(1, 6);
            water_width.push(n_water);
            n += 0.1;

            for x in 0..n_water {
                let idx = build_data.map.xy_idx(x, y);
                build_data.map.tiles[idx] = TileType::DeepWater;
            }

            for x in n_water..n_water + 3 {
                let idx = build_data.map.xy_idx(x, y);
                build_data.map.tiles[idx] = TileType::ShallowWater;
            }
        }
        build_data.take_snapshot();

        // Add piers
        for _i in 0..rng.roll_dice(1, 4) + 6 {
            let y = rng.roll_dice(1, build_data.height) - 1;
            for x in 2 + rng.roll_dice(1, 6)..water_width[y as usize] + 4 {
                let idx = build_data.map.xy_idx(x, y);
                build_data.map.tiles[idx] = TileType::WoodFloor;
            }
        }
        build_data.take_snapshot();
    }
}