fn main() {
    let input = include_bytes!("../sweep_short.raw");

    let min = input.iter().min().unwrap();
    let max = input.iter().max().unwrap();
    let step_size = 0x3;

    println!("len:\t\t{} samples", input.len());
    println!("initial:\t0x{:02x}", input[0]);
    println!("min:\t\t0x{:02x}", min);
    println!("max:\t\t0x{:02x}", max);
    println!("step size:\t0x{:02x}", step_size);

    let mut output: Vec<u8> = Vec::new();

    // let mut max_diff = 0;
    // let prev = input[0];
    // for byte in input {
        
    // }


    let mut sample_pair: u8 = 0;
    let mut index = 0;
    let mut prev = input[0];
    for byte in &input[1..] {
        let (diff, dir) = match byte >= &prev {
            true => ({byte - prev}, 0x1),
            false => ({prev - byte}, 0x0),
        };
        let steps = (diff / step_size) & 0x0E;
        sample_pair |=  ((steps << 1) | dir) << 4 * (index % 2);
        if (index % 2) == 1 {
            output.push(sample_pair);
            sample_pair = 0;
        }
        // println!("0x{:01x} | {}", steps, dir);
        prev = match dir {
            0x1 => prev + (steps * step_size),
            0x0 => prev - (steps * step_size),
            _ => prev + (steps * step_size),
        };
        index += 1;
    }

    // for sample in &output {
        // println!("0x{:02x}", sample);
    // }

    std::fs::write("./sweep_dpcm_u4.raw", &output).unwrap();
}