package common

import (
	"encoding/base64"
	"os"
	"strings"
)

// ImageFileToBase64 reads an image file and returns a data:image/...;base64 string.
func ImageFileToBase64(path string) (string, error) {
	data, err := os.ReadFile(path)
	if err != nil {
		return "", err
	}
	ext := strings.ToLower(pathExt(path))
	mime := "image/png"
	switch ext {
	case ".jpg", ".jpeg":
		mime = "image/jpeg"
	case ".gif":
		mime = "image/gif"
	case ".webp":
		mime = "image/webp"
	}
	return "data:" + mime + ";base64," + base64.StdEncoding.EncodeToString(data), nil
}

// pathExt extracts the extension from a path.
func pathExt(path string) string {
	for i := len(path) - 1; i >= 0 && path[i] != '/'; i-- {
		if path[i] == '.' {
			return path[i:]
		}
	}
	return ""
}