package projectversion

import (
	"bytes"
	"errors"
	"fmt"
	"os"
	"path/filepath"
)

var releaseAssetChecks = []releaseAssetCheck{
	{
		path:        "assets/icon.ico",
		description: "Windows ICO 图标",
		magic:       []byte{0x00, 0x00, 0x01, 0x00},
	},
	{
		path:        "assets/icon.icns",
		description: "macOS ICNS 图标",
		magic:       []byte("icns"),
	},
	{
		path:        "assets/icon.png",
		description: "PNG 图标",
		magic:       []byte{0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a},
	},
	{
		path:        "frontend/public/icon.png",
		description: "前端 PNG 图标",
		magic:       []byte{0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a},
	},
}

var gitLFSPointerPrefix = []byte("version https://git-lfs.github.com/spec/v1")

type releaseAssetCheck struct {
	path        string
	description string
	magic       []byte
}

func CheckReleaseAssets(root string) error {
	var errs []error

	for _, check := range releaseAssetChecks {
		if err := checkReleaseAsset(root, check); err != nil {
			errs = append(errs, err)
		}
	}

	return errors.Join(errs...)
}

func checkReleaseAsset(root string, check releaseAssetCheck) error {
	content, err := os.ReadFile(filepath.Join(root, check.path))
	if err != nil {
		return fmt.Errorf("%s 不可读取: %w", check.path, err)
	}

	if bytes.HasPrefix(content, gitLFSPointerPrefix) {
		return fmt.Errorf("%s 是 Git LFS pointer，请先拉取 Git LFS 真实内容", check.path)
	}

	if !bytes.HasPrefix(content, check.magic) {
		return fmt.Errorf("%s 不是有效的%s", check.path, check.description)
	}

	return nil
}