use pixstrip_core::encoder::OutputEncoder;
use pixstrip_core::types::{ImageFormat, QualityPreset};

fn create_test_rgb_image(width: u32, height: u32) -> image::DynamicImage {
    let img = image::RgbImage::from_fn(width, height, |x, y| {
        image::Rgb([(x % 256) as u8, (y % 256) as u8, 128])
    });
    image::DynamicImage::ImageRgb8(img)
}

fn create_test_rgba_image(width: u32, height: u32) -> image::DynamicImage {
    let img = image::RgbaImage::from_fn(width, height, |x, y| {
        image::Rgba([(x % 256) as u8, (y % 256) as u8, 100, 255])
    });
    image::DynamicImage::ImageRgba8(img)
}

#[test]
fn encode_jpeg() {
    let img = create_test_rgb_image(200, 150);
    let encoder = OutputEncoder::new();
    let bytes = encoder.encode(&img, ImageFormat::Jpeg, Some(85)).unwrap();
    assert!(!bytes.is_empty());
    // JPEG magic bytes
    assert_eq!(bytes[0], 0xFF);
    assert_eq!(bytes[1], 0xD8);
}

#[test]
fn encode_jpeg_quality_affects_size() {
    let img = create_test_rgb_image(200, 150);
    let encoder = OutputEncoder::new();
    let high = encoder.encode(&img, ImageFormat::Jpeg, Some(95)).unwrap();
    let low = encoder.encode(&img, ImageFormat::Jpeg, Some(50)).unwrap();
    assert!(high.len() > low.len(), "Higher quality should produce larger files");
}

#[test]
fn encode_png() {
    let img = create_test_rgba_image(200, 150);
    let encoder = OutputEncoder::new();
    let bytes = encoder.encode(&img, ImageFormat::Png, None).unwrap();
    assert!(!bytes.is_empty());
    // PNG magic bytes
    assert_eq!(&bytes[0..4], &[0x89, 0x50, 0x4E, 0x47]);
}

#[test]
fn encode_webp() {
    let img = create_test_rgb_image(200, 150);
    let encoder = OutputEncoder::new();
    let bytes = encoder.encode(&img, ImageFormat::WebP, Some(80)).unwrap();
    assert!(!bytes.is_empty());
    // RIFF header
    assert_eq!(&bytes[0..4], b"RIFF");
}

#[test]
fn encode_to_file() {
    let img = create_test_rgb_image(200, 150);
    let encoder = OutputEncoder::new();
    let dir = tempfile::tempdir().unwrap();
    let path = dir.path().join("output.jpg");
    encoder.encode_to_file(&img, &path, ImageFormat::Jpeg, Some(85)).unwrap();
    assert!(path.exists());
    let metadata = std::fs::metadata(&path).unwrap();
    assert!(metadata.len() > 0);
}

#[test]
fn quality_from_preset() {
    let encoder = OutputEncoder::new();
    let preset = QualityPreset::High;
    let q = encoder.quality_for_format(ImageFormat::Jpeg, &preset);
    assert_eq!(q, 85);
    let q = encoder.quality_for_format(ImageFormat::WebP, &preset);
    assert!((q as f32 - 85.0).abs() < 1.0);
}

#[test]
fn encode_gif_fallback() {
    let img = create_test_rgba_image(50, 50);
    let encoder = OutputEncoder::new();
    let bytes = encoder.encode(&img, ImageFormat::Gif, None).unwrap();
    assert!(!bytes.is_empty());
    // GIF magic bytes
    assert_eq!(&bytes[0..3], b"GIF");
}