pub mod pixel_format;

use spin::Lazy;
use vga::{colors::Color16, writers::GraphicsWriter};

use crate::vga_e::VGAE;

use pixel_format::*;

pub static SCREEN_BUFFER: Lazy<spin::Mutex<ScreenBuffer>> =
    Lazy::new(|| spin::Mutex::new(ScreenBuffer::new(640, 480)));

const FONT_SCALE: f32 = 1.6;

const GLYPH_HEIGHT: f32 = 18.0;
const GLYPH_WIDTH: f32 = 10.0;

#[derive(Debug)]
pub struct ScreenSize {
    pub x: usize,
    pub y: usize,
}

impl ScreenSize {
    pub fn new(x: usize, y: usize) -> Self {
        Self { x, y }
    }
}

pub enum GraphicsReturn {
    Ok,
    ImproperScreenSize,
}

pub struct ScreenBuffer {
    pub size: ScreenSize,
    pub clear_color: Rgba64,
    pub buff: Box<[Rgba64]>,
}

impl ScreenBuffer {
    // Add optional size later
    pub fn new(x: usize, y: usize) -> Self {
        Self {
            size: ScreenSize::new(x, y),
            clear_color: 0,
            buff: vec![0u64; x * y].into_boxed_slice(),
        }
    }

    pub fn draw_filled_circle(&mut self, cx: i32, cy: i32, radius: usize, color: Rgba64) {
        let r = radius as i32 * 2;
        for y in 0..640 {
            for x in 0..480 {
                let dx = cx - x as i32 * 2 - 1;
                let dy = cy - y as i32 * 2 - 1;

                if dx * dx + dy * dy <= r * r {
                    self.set_pixel(x, y, color);
                };
            }
        }
    }

    #[inline]
    pub fn set_pixel(&mut self, x: usize, y: usize, color: Rgba64) {
        self.buff[y * self.size.x + x] = color;
    }

    pub fn clear(&mut self) {
        self.buff = vec![0u64; self.buff.len()].into_boxed_slice();
    }

    pub fn blit(&mut self, _width: usize, _height: usize) {}

    pub fn draw_filled_rect(&mut self, x1: usize, y1: usize, x2: usize, y2: usize, color: Rgba64) {
        for y in y1..y2 {
            for x in x1..x2 {
                self.set_pixel(x, y, color);
            }
        }
    }
    pub fn draw_unfilled_rect(
        &mut self,
        x1: usize,
        y1: usize,
        x2: usize,
        y2: usize,
        color: Rgba64,
    ) {
        // x1 y1 => x2 y1 => x2 y2 => x1 y2 => x1 y1
        self.draw_line(x1, y1, x2, y1, color);
        self.draw_line(x2, y1, x2, y2, color);
        self.draw_line(x2, y2, x1, y2, color);
        self.draw_line(x1, y2, x1, y1, color);
    }

    #[inline]
    pub fn draw_line(&mut self, x1: usize, y1: usize, x2: usize, y2: usize, color: Rgba64) {
        let x = crate::graphics::get_coordinates(
            x1.try_into().unwrap(),
            y1.try_into().unwrap(),
            x2.try_into().unwrap(),
            y2.try_into().unwrap(),
        );

        for coord in x {
            self.set_pixel(coord.0, coord.1, color);
        }
    }

    // pub fn shade(&mut self) {
    //     for y in 0..100 {
    //         for x in 0..100 {
    //             let rgba_ret = evaluate_shader(x, y, self.buff[y * self.size.x + x]);
    //             match rgba_ret {
    //                 Ok(pixel) => {
    //                     // info!("{:?}", pixel);
    //                     self.set_pixel(x, y, pixel);
    //                 }

    //                 Err(err) => error!("{}", err),
    //             }
    //         }
    //     }

    //     info!("Shaders done");
    // }

    // TODO force clear
    pub fn force_redraw(&mut self) {
        let vga = VGAE.lock();
        vga.set_mode();
        vga.clear_screen(vga::colors::Color16::Black);
    }
}

pub fn get_coordinates(x1: i32, y1: i32, x2: i32, y2: i32) -> Vec<(usize, usize)> {
    let mut coordinates: Vec<(usize, usize)> = vec![];
    let dx: i32 = i32::abs(x2 - x1);
    let dy: i32 = i32::abs(y2 - y1);
    let sx: i32 = {
        if x1 < x2 {
            1
        } else {
            -1
        }
    };
    let sy: i32 = {
        if y1 < y2 {
            1
        } else {
            -1
        }
    };
    let mut error: i32 = (if dx > dy { dx } else { -dy }) / 2;
    let mut current_x: i32 = x1;
    let mut current_y: i32 = y1;
    loop {
        coordinates.push((current_x as usize, current_y as usize));
        // info!("0  {:?}", (current_x, current_y));

        if current_x == x2 && current_y == y2 {
            break;
        }

        let error2: i32 = error;

        if error2 > -dx {
            error -= dy;
            current_x += sx;
        }
        if error2 < dy {
            error += dx;
            current_y += sy;
        }
    }

    coordinates
}

pub trait VgaBuffer {
    fn copy_to_buffer(&self) -> GraphicsReturn;
}
impl VgaBuffer for ScreenBuffer {
    fn copy_to_buffer(&self) -> GraphicsReturn {
        let mode = VGAE.lock();
        for y in 0..self.size.y {
            for x in 0..self.size.x {
                let vga_color = into_vga_16(self.buff[y * self.size.x + x]);
                if into_vga_16(self.clear_color) != vga_color {
                    mode.set_pixel(x, y, vga_color);
                }
            }
        }
        GraphicsReturn::Ok
    }
}

pub fn into_vga_16(rgba_64: Rgba64) -> Color16 {
    use pixel_format::ChannelValue::*;
    use vga::colors::Color16::*;
    match (
        get_r(rgba_64).into(),
        get_g(rgba_64).into(),
        get_b(rgba_64).into(),
    ) {
        (Dark, Dark, Dark) => Black,
        (Dark, Dark, Low) => Black,
        (Dark, Dark, Mid) => Blue,
        (Dark, Dark, High) => Blue,
        (Dark, Low, Dark) => Black,
        (Dark, Low, Low) => Black,
        (Dark, Low, Mid) => Blue,
        (Dark, Low, High) => Blue,
        (Dark, Mid, Dark) => Green,
        (Dark, Mid, Low) => Green,
        (Dark, Mid, Mid) => Cyan,
        (Dark, Mid, High) => Cyan,
        (Dark, High, Dark) => Green,
        (Dark, High, Low) => Green,
        (Dark, High, Mid) => Green,
        (Dark, High, High) => Cyan,
        (Low, Dark, Dark) => Black,
        (Low, Dark, Low) => Black,
        (Low, Dark, Mid) => Blue,
        (Low, Dark, High) => Blue,
        (Low, Low, Dark) => Black,
        (Low, Low, Low) => DarkGrey,
        (Low, Low, Mid) => LightGrey,
        (Low, Low, High) => Blue,
        (Low, Mid, Dark) => DarkGrey,
        (Low, Mid, Low) => LightGrey,
        (Low, Mid, Mid) => Cyan,
        (Low, Mid, High) => Cyan,
        (Low, High, Dark) => Green,
        (Low, High, Low) => Green,
        (Low, High, Mid) => Cyan,
        (Low, High, High) => Cyan,
        (Mid, Dark, Dark) => Red,
        (Mid, Dark, Low) => Red,
        (Mid, Dark, Mid) => Magenta,
        (Mid, Dark, High) => Magenta,
        (Mid, Low, Dark) => Brown,
        (Mid, Low, Low) => Red,
        (Mid, Low, Mid) => DarkGrey,
        (Mid, Low, High) => LightBlue,
        (Mid, Mid, Dark) => Brown,
        (Mid, Mid, Low) => Brown,
        (Mid, Mid, Mid) => LightGrey,
        (Mid, Mid, High) => LightBlue,
        (Mid, High, Dark) => Green,
        (Mid, High, Low) => Green,
        (Mid, High, Mid) => LightGreen,
        (Mid, High, High) => LightCyan,
        (High, Dark, Dark) => Red,
        (High, Dark, _) => Magenta,
        (High, Low, Dark) => Red,
        (High, Low, Low) => LightRed,
        (High, Low, Mid) => Pink,
        (High, Low, High) => Magenta,
        (High, Mid, Dark) => Yellow,
        (High, Mid, Low) => Yellow,
        (High, Mid, Mid) => LightRed,
        (High, Mid, High) => Pink,
        (High, High, Dark) => Yellow,
        (High, High, Low) => White,
        (High, High, Mid) => White,
        (High, High, High) => White,
    }
}

// TODO: Incorporate this into the ableos vga crate
// /// Draw a glyph on the screen at the given position
// ///
// /// # Arguments
// /// * `x` - the x position of the glyph
// /// * `y` - the y position of the glyph
// /// * `glyph` - the glyph to draw
// /// * `color` - the color of the glyph
// pub fn draw_char(&mut self, mut x: u32, mut y: u32, character: char, color: Rgba64) {
//     // trace!["Judy Hopps is thicc af"];
//     // let mode = *VGAE.lock();
//     // trace!["She got them bouncy bunny buns"];

//     let basic_multingual_plane = FontRef::try_from_slice(include_bytes!(
//         "../../../ableos/assets/fonts/unifont-14.0.01.ttf"
//     ))
//     .unwrap();

//     let supplementary_multilingual_plane = FontRef::try_from_slice(include_bytes!(
//         "../../../ableos/assets/fonts/unifont_upper-14.0.01.ttf"
//     ))
//     .unwrap();

//     // let mut has_char = false;
//     // for x in font.codepoint_ids() {
//     //    if x.1 == character {
//     //       has_char = true;
//     //       break;
//     //    }
//     // }

//     let in_supp_plane = character as u32 > 0xffff;

//     let plane = match in_supp_plane {
//         false => basic_multingual_plane,
//         true => supplementary_multilingual_plane,
//     };

//     match character {
//         '\n' => {
//             // x = 0;
//             // y += (GLYPH_HEIGHT * FONT_SCALE) as u32;
//         }
//         _ => {
//             let q_glyph: Glyph = plane.glyph_id(character).with_scale_and_position(
//                 20.0 * FONT_SCALE,
//                 ab_glyph::point(GLYPH_WIDTH * FONT_SCALE, GLYPH_HEIGHT * FONT_SCALE),
//             );

//             // elf: I don't know if GLYPH_HEIGHT is in the right units here. I'm just guessing.
//             if x as usize > self.size.x {
//                 x = 0;
//                 y += (GLYPH_HEIGHT * FONT_SCALE) as u32;
//             }

//             if let Some(q) = plane.outline_glyph(q_glyph) {
//                 q.draw(|gx, gy, c| {
//                     if c > 0.0015 {
//                         let corner = q.px_bounds().min;
//                         self.set_pixel(
//                             gx as usize + corner.x as usize + x as usize,
//                             gy as usize + corner.y as usize + y as usize,
//                             color,
//                         );
//                     }
//                 });
//             }
//         }
//     }
// }