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use crate::bit::BitStreamWriter;
use crate::{Bmp, BmpError, BmpHeader, B, HEADER_SIZE, M};
use std::io::Write;

impl Bmp {
    /// Write the monochrome bitmap to a Write type, such a File
    pub fn write<T: Write>(&self, mut to: T) -> Result<(), BmpError> {
        let width = self.width as u32;
        let height = self.height() as u32;
        let header = BmpHeader { height, width };
        let padding = header.padding() as u8;

        header.write(&mut to)?;

        let mut writer = BitStreamWriter::new(&mut to);

        for i in 0..height as usize {
            for j in 0..width as usize {
                if self.get(i, j) {
                    writer.write(1, 1)?;
                } else {
                    writer.write(0, 1)?;
                }
            }
            writer.write(0, 8 - (width % 8) as u8)?;
            writer.write(0, padding * 8)?;
        }
        writer.flush()?;

        Ok(())
    }
}

impl BmpHeader {
    pub fn write<T: Write>(&self, to: &mut T) -> Result<(), BmpError> {
        let bytes_per_row = self.bytes_per_row();
        let padding = self.padding();
        let data_size = (bytes_per_row + padding) * (self.height as u32);
        let total_size = HEADER_SIZE + data_size;

        to.write_all(&[B, M])?;
        to.write_all(&total_size.to_le_bytes())?; // size of the bmp
        to.write_all(&0u16.to_le_bytes())?; // creator1
        to.write_all(&0u16.to_le_bytes())?; // creator2
        to.write_all(&HEADER_SIZE.to_le_bytes())?; // pixel offset
        to.write_all(&40u32.to_le_bytes())?; // dib header size
        to.write_all(&(self.width as u32).to_le_bytes())?; // width
        to.write_all(&(self.height as u32).to_le_bytes())?; // height
        to.write_all(&1u16.to_le_bytes())?; // planes
        to.write_all(&1u16.to_le_bytes())?; // bitsperpixel
        to.write_all(&0u32.to_le_bytes())?; // no compression
        to.write_all(&data_size.to_le_bytes())?; // size of the raw bitmap data with padding
        to.write_all(&512u32.to_le_bytes())?; // hres
        to.write_all(&512u32.to_le_bytes())?; // vres
        to.write_all(&2u32.to_le_bytes())?; // num_colors
        to.write_all(&2u32.to_le_bytes())?; // num_imp_colors
        to.write_all(&0x00_FF_FF_FFu32.to_le_bytes())?; // color_pallet 0
        to.write_all(&0x00_00_00_00u32.to_le_bytes())?; // color_pallet 1

        Ok(())
    }
}