package imageutil

import (
	"bytes"
	"fmt"
	"image"
	_ "image/gif"
	_ "image/jpeg"
	_ "image/png"
	"io"

	"github.com/chai2010/webp"
)

type ProcessOptions struct {
	Lossless    bool
	Quality     float32 // 0-100
	Compression int     // 0-6
}

// DefaultOptions returns default processing options
func DefaultOptions() ProcessOptions {
	return ProcessOptions{
		Lossless:    true,
		Quality:     90,
		Compression: 4,
	}
}

// ProcessImage converts any supported image to WebP format
func ProcessImage(input io.Reader, opts ProcessOptions) ([]byte, error) {
	// Decode the original image
	img, _, err := image.Decode(input)
	if err != nil {
		return nil, fmt.Errorf("failed to decode image: %w", err)
	}

	// Encode to WebP
	var buf bytes.Buffer
	if err := webp.Encode(&buf, img, &webp.Options{
		Lossless: opts.Lossless,
		Quality:  opts.Quality,
		Exact:    true,
	}); err != nil {
		return nil, fmt.Errorf("failed to encode to WebP: %w", err)
	}

	return buf.Bytes(), nil
}

// IsImageFormat checks if the given format is a supported image format
func IsImageFormat(contentType string) bool {
	switch contentType {
	case "image/jpeg", "image/png", "image/gif", "image/webp":
		return true
	default:
		return false
	}
}