use hcie_protocol::Layer;
use hcie_protocol::effects::LayerEffect;
use std::path::Path;

fn main() {
    let output_dir = Path::new("_tmp/psd_test_output");
    std::fs::create_dir_all(output_dir).ok();

    println!("=== Generate Test PSDs ===");

    // Test 1: Simple layer, no effects
    {
        let layers = vec![
            Layer::new_blank("Background", 256, 256),
        ];
        let composited = vec![255u8; 256 * 256 * 4];
        let path = output_dir.join("test_simple.psd");
        hcie_psd::save_psd(&layers, 256, 256, &composited, &path).unwrap();
        verify_psd(&path, "Simple (no effects)");
    }

    // Test 2: Layer with InnerShadow effect
    {
        let mut layer = Layer::new_blank("Effect Layer", 256, 256);
        layer.effects.push(LayerEffect::InnerShadow {
            enabled: true,
            blend_mode: "normal".to_string(),
            color: [0, 0, 0, 255],
            opacity: 0.75,
            angle: 120.0,
            distance: 10.0,
            choke: 5.0,
            size: 15.0,
            noise: 0.0,
            contour: None,
        });
        let layers = vec![layer];
        let composited = vec![255u8; 256 * 256 * 4];
        let path = output_dir.join("test_inner_shadow.psd");
        hcie_psd::save_psd(&layers, 256, 256, &composited, &path).unwrap();
        verify_psd(&path, "InnerShadow");
    }

    // Test 3: Two layers, one with effects
    {
        let bg = Layer::new_blank("Background", 256, 256);
        let mut fg = Layer::new_blank("Foreground", 256, 256);
        fg.effects.push(LayerEffect::DropShadow {
            enabled: true,
            blend_mode: "normal".to_string(),
            color: [0, 0, 0, 255],
            opacity: 0.5,
            angle: 120.0,
            distance: 5.0,
            spread: 0.0,
            size: 10.0,
            noise: 0.0,
            contour: None,
        });
        let layers = vec![bg, fg];
        let composited = vec![255u8; 256 * 256 * 4];
        let path = output_dir.join("test_two_layers.psd");
        hcie_psd::save_psd(&layers, 256, 256, &composited, &path).unwrap();
        verify_psd(&path, "Two layers + DropShadow");
    }

    // Test 4: Roundtrip the reference PSD
    {
        let ref_path = Path::new("_images/_psd_stil_test/inner_shadow/black_triangle_green_inner_shadow_normal_blend.psd");
        if ref_path.exists() {
            let layers = hcie_psd::import_psd(ref_path).unwrap();
            let orig_bytes = std::fs::read(ref_path).unwrap();
            let psd = hcie_psd::Psd::from_bytes(&orig_bytes).unwrap();
            let composited = psd.rgba();
            let path = output_dir.join("test_roundtrip.psd");
            hcie_psd::save_psd(&layers, psd.width(), psd.height(), &composited, &path).unwrap();
            verify_psd(&path, "Roundtrip from reference PSD");
        }
    }

    // Test 5: Verify pixel data round-trip
    {
        println!("\n=== Pixel Data Verification ===");
        let ref_path = Path::new("_images/_psd_stil_test/inner_shadow/black_triangle_green_inner_shadow_normal_blend.psd");
        if ref_path.exists() {
            let orig_bytes = std::fs::read(ref_path).unwrap();
            let orig_psd = hcie_psd::Psd::from_bytes(&orig_bytes).unwrap();
            let orig_rgba = orig_psd.rgba();

            let saved_path = output_dir.join("test_roundtrip.psd");
            let saved_bytes = std::fs::read(&saved_path).unwrap();
            let saved_psd = hcie_psd::Psd::from_bytes(&saved_bytes).unwrap();
            let saved_rgba = saved_psd.rgba();

            let mut diff_count = 0;
            let mut max_diff: u8 = 0;
            for i in 0..orig_rgba.len().min(saved_rgba.len()) {
                let d = (orig_rgba[i] as i16 - saved_rgba[i] as i16).unsigned_abs() as u8;
                if d > 0 {
                    diff_count += 1;
                    max_diff = max_diff.max(d);
                }
            }
            println!("Original RGBA: {} bytes", orig_rgba.len());
            println!("Saved RGBA: {} bytes", saved_rgba.len());
            println!("Differing bytes: {} / {}", diff_count, orig_rgba.len());
            println!("Max per-byte diff: {}", max_diff);
            println!("MAE: {:.2}", diff_count as f64 / orig_rgba.len() as f64);
        }
    }
}

fn verify_psd(path: &Path, label: &str) {
    let bytes = std::fs::read(path).unwrap();
    match hcie_psd::Psd::from_bytes(&bytes) {
        Ok(psd) => {
            println!("[OK] {}: {} bytes, {}x{}, {} layers",
                label, bytes.len(), psd.width(), psd.height(), psd.layers().len());
        }
        Err(e) => {
            println!("[FAIL] {}: {} bytes, error: {:?}", label, bytes.len(), e);
        }
    }
}