use crate::{
    block::{Block, BlockInner},
    frame::Frame,
    view::View,
};

pub fn encode_block(view: View<&Frame>, prev: View<&Frame>) -> Block {
    let diff = View::diff(&view, &prev) / view.area() as f64;
    // eprintln!("{:?} {diff}", view.size);
    let inner = if diff < 0.9 {
        BlockInner::Reference {
            translation: (0, 0),
        }
    } else {
        if view.size.0 < 16 {
            BlockInner::Literal(view.pixels())
        } else {
            let [av, bv] = view.split();
            let [ap, bp] = prev.split();
            let a = encode_block(av, ap);
            let b = encode_block(bv, bp);
            if a.is_literal() && b.is_literal() {
                BlockInner::Literal(view.pixels())
            } else {
                BlockInner::Split(Box::new([a, b]))
            }
        }
    };

    Block {
        size: view.size,
        inner,
    }
}