import type { ExportSettings } from "./settings"

/**
 * The pure jSquash encode: downscale (Lanczos) when the scale is below
 * 100%, then encode through the format's codec. Each codec is imported
 * lazily so its wasm downloads only when the format is first used. Runs in
 * any JS context — the worker, the main thread, or node tests.
 */
export const encodeImage = async (
  image: ImageData,
  settings: ExportSettings,
): Promise<Uint8Array> => {
  let source = image
  if (settings.scale !== 1) {
    // oxlint-disable-next-line ts-no-dynamic-import
    const { default: resize } = await import("@jsquash/resize")
    source = await resize(image, {
      width: Math.max(1, Math.round(image.width * settings.scale)),
      height: Math.max(1, Math.round(image.height * settings.scale)),
      method: "lanczos3",
    })
  }
  const quality = settings.quality ?? 75
  switch (settings.format) {
    case "png": {
      // oxlint-disable-next-line ts-no-dynamic-import -- lazy codec load
      const { encode } = await import("@jsquash/png")
      return new Uint8Array(await encode(source))
    }
    case "jpeg": {
      // oxlint-disable-next-line ts-no-dynamic-import -- lazy codec load
      const { encode } = await import("@jsquash/jpeg")
      return new Uint8Array(await encode(source, { quality }))
    }
    case "webp": {
      // oxlint-disable-next-line ts-no-dynamic-import -- lazy codec load
      const { encode } = await import("@jsquash/webp")
      return new Uint8Array(await encode(source, { quality }))
    }
    case "avif": {
      // oxlint-disable-next-line ts-no-dynamic-import -- lazy codec load
      const { encode } = await import("@jsquash/avif")
      return new Uint8Array(await encode(source, { quality }))
    }
  }
}