use std::{f32::consts::PI, path::{Path, PathBuf}};

use teleia::*;

use rand::Rng;

pub const PLANE_SIZE: f32 = 12.0;
pub const FOOTSTEP_TIME: u64 = 90;

#[derive(Debug)]
pub struct Config {
    pub name: String,
    pub credits: String,
    pub links: String,
    pub size: f32,
    pub speed: f32,
    pub fov: f32,
    pub texture_repeat: f32,
    pub room_height: f32,
    pub layer_frames: f32,
    pub fog_color: glam::Vec3,
    pub fog_end: f32,
    pub mini_speed: f32,
}
impl Default for Config {
    fn default() -> Self {
        Self {
            name: "".to_owned(),
            credits: "".to_owned(),
            links: "".to_owned(),
            size: 1.0,
            speed: 1.0,
            fov: 55.0,
            texture_repeat: 3.0,
            room_height: 350.0,
            layer_frames: 1.0,
            fog_color: glam::Vec3::ZERO,
            fog_end: -1.0,
            mini_speed: 1.0,
        }
    }
}
impl Config {
    pub fn from_room_ini(bs: Vec<u8>) -> Erm<Self> {
        let mut ret = Self::default();
        let contents = String::from_utf8(bs)?;
        let i = ini::Ini::load_from_str(&contents)?;
        let Some(sec) = i.section::<&str>(None) else { return utils::erm_msg("failed to get properties"); };
        if let Some(x) = sec.get("name") { ret.name = x.to_owned(); }
        if let Some(x) = sec.get("credits") { ret.credits = x.to_owned(); }
        if let Some(x) = sec.get("links") { ret.links = x.to_owned(); }
        if let Some(x) = sec.get("size") { ret.size = x.parse()?; }
        if let Some(x) = sec.get("speed") { ret.speed = x.parse()?; }
        if let Some(x) = sec.get("FOV") { ret.fov = x.parse()?; }
        if let Some(x) = sec.get("Texture_Repeat") { ret.texture_repeat = x.parse()?; }
        if let Some(x) = sec.get("Room_Height") { ret.room_height = x.parse::<f32>()? / 350.0; }
        if let Some(x) = sec.get("Layer_Frames") { ret.layer_frames = x.parse()?; }
        if let Some(x) = sec.get("Fog_Color") {
            let num: u64 = x.parse()?;
            ret.fog_color = glam::Vec3::new(
                (num & 0xff) as f32 / 255.0,
                (num >> 8 & 0xff) as f32 / 255.0,
                (num >> 16 & 0xff) as f32 / 255.0,
            );
        }
        if let Some(x) = sec.get("Fog_End") { ret.fog_end = x.parse::<f32>()? / 10.0; }
        if let Some(x) = sec.get("Mini_speed") { ret.mini_speed = x.parse::<f32>()? / 60.0; }
        Ok(ret)
    }
}

pub struct Room {
    pub config: Config,
    pub shader: shader::Shader,
    pub floor: texture::Texture,
    pub wall: texture::Texture,
    pub roof: texture::Texture,
    pub art: texture::Texture,
    pub credit: texture::Texture,
    pub mini: texture::Texture, pub has_mini: bool, pub mini_frame: u64,
    pub mini_pos: glam::Vec2, pub mini_dir: glam::Vec2,
    pub interact: texture::Texture, pub has_interact: bool,
    pub layer: texture::Texture, pub has_layer: bool, pub layer_frame: u64,
    pub interact_mode: ui::Mode,
    pub credit_mode: ui::Mode,
    pub music: Option<(audio::Audio, audio::AudioPlayingHandle)>,
    pub foot: Option<audio::Audio>, pub foot_countdown: u64,
}
impl Room {
    pub fn new(ctx: &context::Context, shader: shader::Shader) -> Self {
        Self {
            config: Config::default(),
            shader,
            floor: texture::Texture::new_empty(ctx),
            wall: texture::Texture::new_empty(ctx),
            roof: texture::Texture::new_empty(ctx),
            art: texture::Texture::new_empty(ctx),
            credit: texture::Texture::new_empty(ctx),
            mini: texture::Texture::new_empty(ctx), has_mini: false, mini_frame: 0,
            mini_pos: glam::Vec2::new(4.0, 4.0), mini_dir: glam::Vec2::new(1.0, 0.0),
            interact: texture::Texture::new_empty(ctx), has_interact: false,
            layer: texture::Texture::new_empty(ctx), has_layer: false, layer_frame: 0,
            interact_mode: ui::Mode::new(20),
            credit_mode: ui::Mode::new(10),
            music: None,
            foot: None,
            foot_countdown: 0,
        }
    }
    fn load_file(base: impl AsRef<Path>, needle: &str) -> Erm<Vec<u8>> {
        let base = base.as_ref();
        let uneedle = needle.to_uppercase();
        for mp in std::fs::read_dir(base)? {
            if let Ok(p) = mp && let Some(onm) = p.path().file_name() && let Some(nm) = onm.to_str() {
                if nm.to_uppercase().contains(&uneedle) {
                    return Ok(std::fs::read(p.path())?);
                }
            }
        }
        utils::erm_msg(&format!("failed to find {} in {}", needle, base.display()))
    }
    pub fn load_from_bytes(
        &mut self, ctx: &context::Context, st: &mut state::State,
        config: Option<&[u8]>,
        floor: &[u8], wall: &[u8], roof: &[u8], art: &[u8], credit: &[u8],
        mini: Option<&[u8]>, interact: Option<&[u8]>, layer: Option<&[u8]>, 
        music: Option<&[u8]>, foot: Option<&[u8]>,
    ) -> Erm<()> {
        self.config = Config::default();
        if let Some(bs) = config {
            self.config = Config::from_room_ini(bs.to_owned())?;
        }
        self.floor.upload(ctx, floor); self.floor.set_repeat(ctx);
        self.wall.upload(ctx, wall); self.wall.set_repeat(ctx);
        self.roof.upload(ctx, roof); self.roof.set_repeat(ctx);
        self.art.upload(ctx, art);
        self.credit.upload(ctx, credit);
        if let Some(bs) = mini {
            self.mini.upload(ctx, &bs);
            self.has_mini = true;
        } else { self.has_mini = false; }
        if let Some(bs) = interact {
            self.interact.upload(ctx, &bs);
            self.has_interact = true;
        } else { self.has_interact = false; }
        if let Some(bs) = layer {
            self.layer.upload(ctx, &bs);
            self.has_layer = true;
        } else { self.has_layer = false; }
        if let Some(bs) = music && let Some(audio) = st.audio.as_mut() {
            let m = audio::Audio::new(&audio.ctx, &bs);
            if let Some(handle) = m.play(&mut audio.ctx, Some((None, None))) {
                self.music = Some((m, handle))
            }
        } else { self.music = None; }
        if let Some(bs) = foot && let Some(audio) = st.audio.as_mut() {
            let m = audio::Audio::new(&audio.ctx, &bs);
            self.foot = Some(m);
        } else { self.foot = None; }
        Ok(())
    }
    pub fn load(&mut self, ctx: &context::Context, st: &mut state::State, dir: &str) -> Erm<()> {
        let base = PathBuf::from(dir);
        self.load_from_bytes(ctx, st,
            Self::load_file(&base, "ROOM").ok().as_deref(),
            &Self::load_file(&base, "FLOOR")?,
            &Self::load_file(&base, "WALL")?,
            &Self::load_file(&base, "ROOF")?,
            &Self::load_file(&base, "ART")?,
            &Self::load_file(&base, "CREDIT")?,
            Self::load_file(&base, "MINI").ok().as_deref(),
            Self::load_file(&base, "INTERACT").ok().as_deref(),
            Self::load_file(&base, "LAYER").ok().as_deref(),
            Self::load_file(&base, "MUSIC").ok().as_deref(),
            Self::load_file(&base, "FOOT").ok().as_deref(),
        )?;
        Ok(())
    }
    pub fn footstep(&mut self, _ctx: &context::Context, st: &mut state::State) -> Erm<()> {
        if let Some(f) = &self.foot && let Some(audio) = st.audio.as_mut() {
            if self.foot_countdown == 0 {
                f.play(&mut audio.ctx, None);
                self.foot_countdown = FOOTSTEP_TIME;
            } else {
                self.foot_countdown -= 1;
            }
        }
        Ok(())
    }
    pub fn render(&mut self, ctx: &context::Context, st: &mut state::State, yaw: f32) -> Erm<()> {
        let scale = st.render_dims.x / 640.0;
        st.projection = glam::Mat4::perspective_lh(
            self.config.fov * PI / 180.0,
            st.render_dims.x / st.render_dims.y,
            0.5,
            50.0,
        );
        st.bind_3d(ctx, &self.shader);
        self.shader.set_vec2(ctx, "texture_scale",
            &glam::Vec2::new(self.config.texture_repeat, self.config.texture_repeat)
        );
        self.shader.set_f32(ctx, "fog_distance", self.config.fog_end);
        self.shader.set_vec3(ctx, "fog_color", &self.config.fog_color);
        self.floor.bind(ctx);
        self.shader.set_position_3d(
            ctx, st,
            &glam::Mat4::from_scale_rotation_translation(
                glam::Vec3::new(PLANE_SIZE, PLANE_SIZE, 1.0),
                glam::Quat::from_rotation_x(PI / 2.0),
                glam::Vec3::new(0.0, 0.0, 0.0),
            ),
        );
        st.mesh_square.render(ctx);
        self.roof.bind(ctx);
        self.shader.set_position_3d(
            ctx, st,
            &glam::Mat4::from_scale_rotation_translation(
                glam::Vec3::new(PLANE_SIZE, PLANE_SIZE, 1.0),
                glam::Quat::from_rotation_x(3.0 * PI / 2.0),
                glam::Vec3::new(0.0, self.config.room_height * PLANE_SIZE * 2.0, 0.0),
            ),
        );
        st.mesh_square.render(ctx);
        self.wall.bind(ctx);
        let wallpos = [
            glam::Mat4::from_scale_rotation_translation(
                glam::Vec3::new(PLANE_SIZE, PLANE_SIZE, 1.0),
                glam::Quat::from_rotation_y(0.0),
                glam::Vec3::new(0.0, PLANE_SIZE, PLANE_SIZE),
            ),
            glam::Mat4::from_scale_rotation_translation(
                glam::Vec3::new(PLANE_SIZE, PLANE_SIZE, 1.0),
                glam::Quat::from_rotation_y(PI),
                glam::Vec3::new(0.0, PLANE_SIZE, -PLANE_SIZE),
            ),
            glam::Mat4::from_scale_rotation_translation(
                glam::Vec3::new(PLANE_SIZE, PLANE_SIZE, 1.0),
                glam::Quat::from_rotation_y(PI / 2.0),
                glam::Vec3::new(PLANE_SIZE, PLANE_SIZE, 0.0),
            ),
            glam::Mat4::from_scale_rotation_translation(
                glam::Vec3::new(PLANE_SIZE, PLANE_SIZE, 1.0),
                glam::Quat::from_rotation_y(3.0 * PI / 2.0),
                glam::Vec3::new(-PLANE_SIZE, PLANE_SIZE, 0.0),
            ),
        ];
        for wp in wallpos {
            self.shader.set_position_3d(ctx, st, &wp);
            st.mesh_square.render(ctx);
        }
        self.shader.set_vec2(ctx, "texture_scale", &glam::Vec2::new(1.0, 1.0));
        self.art.bind(ctx);
        self.shader.set_position_3d(
            ctx, st,
            &glam::Mat4::from_scale_rotation_translation(
                glam::Vec3::new(1.0, 1.0, 1.0),
                glam::Quat::from_rotation_y(yaw),
                glam::Vec3::new(0.0, 1.0, 0.0),
            ),
        );
        st.mesh_square.render(ctx);
        if self.has_mini {
            self.mini.bind(ctx);
            let xscale = 1.0 / 4.0;
            let xoffset = xscale * self.mini_frame as f32;
            if st.tick % 10 == 0 {
                self.mini_frame += 1;
                self.mini_frame %= 4;
            }
            self.shader.set_vec2(ctx, "texture_scale", &glam::Vec2::new(xscale, 1.0));
            self.shader.set_vec2(ctx, "texture_offset", &glam::Vec2::new(xoffset, 0.0));
            self.shader.set_position_3d(
                ctx, st,
                &glam::Mat4::from_scale_rotation_translation(
                    glam::Vec3::new(0.25, 0.25, 1.0),
                    glam::Quat::from_rotation_y(yaw),
                    glam::Vec3::new(self.mini_pos.x, 0.25, self.mini_pos.y),
                ),
            );
            st.mesh_square.render(ctx);
            self.shader.set_vec2(ctx, "texture_scale", &glam::Vec2::new(1.0, 1.0));
            self.shader.set_vec2(ctx, "texture_offset", &glam::Vec2::new(0.0, 0.0));
            let newpos = self.mini_pos + self.config.mini_speed * self.mini_dir;
            if newpos.x.abs() > PLANE_SIZE || newpos.y.abs() > PLANE_SIZE {
                let angle = rand::thread_rng().gen_range(0..360) as f32 * PI / 180.0;
                self.mini_dir = glam::Vec2::new(angle.cos(), angle.sin());
            } else {
                self.mini_pos = newpos;
            }
        }

        ctx.clear_depth();
        self.shader.set_f32(ctx, "fog_distance", -1.0);
        if self.has_layer {
            st.bind_2d(ctx, &self.shader);
            let xscale = 1.0 / self.config.layer_frames;
            let xoffset = xscale * self.layer_frame as f32;
            if st.tick % 10 == 0 {
                self.layer_frame += 1;
                self.layer_frame %= self.config.layer_frames as u64;
            }
            self.shader.set_vec2(ctx, "texture_scale", &glam::Vec2::new(xscale, 1.0));
            self.shader.set_vec2(ctx, "texture_offset", &glam::Vec2::new(xoffset, 0.0));
            self.layer.bind(ctx);
            self.shader.set_position_2d(
                ctx, st,
                &glam::Vec2::new(0.0, 0.0),
                &st.render_dims,
            );
            st.mesh_square.render(ctx);
            self.shader.set_vec2(ctx, "texture_scale", &glam::Vec2::new(1.0, 1.0));
            self.shader.set_vec2(ctx, "texture_offset", &glam::Vec2::new(0.0, 0.0));
        }
        if self.has_interact {
            st.bind_2d(ctx, &self.shader);
            self.shader.set_f32(ctx, "opacity", self.interact_mode.progress(st.tick));
            self.interact.bind(ctx);
            let iwidth = self.interact.width as f32 * scale;
            let iheight = iwidth * (self.interact.height as f32 / self.interact.width as f32);
            self.shader.set_position_2d(
                ctx, st,
                &glam::Vec2::new(0.0, 0.0),
                &glam::Vec2::new(iwidth, iheight),
            );
            st.mesh_square.render(ctx);
            self.shader.set_f32(ctx, "opacity", 1.0);
        }
        st.bind_2d(ctx, &self.shader);
        self.credit.bind(ctx);
        let cwidth = self.credit.width as f32 * scale;
        let cheight = cwidth * (self.credit.height as f32 / self.credit.width as f32);
        self.shader.set_position_2d(
            ctx, st,
            &glam::Vec2::new(st.render_dims.x - cwidth,
                utils::lerp(
                    st.render_dims.y,
                    st.render_dims.y - cheight,
                    self.credit_mode.progress(st.tick),
                ),
            ),
            &glam::Vec2::new(cwidth, cheight),
        );
        st.mesh_square.render(ctx);
        Ok(())
    }
}