package common

import (
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/gogf/gf/v2/net/ghttp"
)

var allowedImageExt = map[string]bool{".jpg": true, ".jpeg": true, ".png": true, ".webp": true}

// SaveUploadedFile 保存上传文件到 workspace/{subDir}，返回访问路径 /workspace/{subDir}/{filename}
func SaveUploadedFile(file *ghttp.UploadFile, subDir string) (string, error) {
	if file == nil {
		return "", errors.New("未收到文件")
	}
	ext := strings.ToLower(filepath.Ext(file.Filename))
	if !allowedImageExt[ext] {
		return "", errors.New("仅支持 jpg/jpeg/png/webp 格式")
	}
	if file.Size > 10*1024*1024 {
		return "", errors.New("单张图片不能超过 10MB")
	}
	dir := filepath.Join("workspace", subDir)
	if err := os.MkdirAll(dir, 0o755); err != nil {
		return "", err
	}
	filename := fmt.Sprintf("%d%s", time.Now().UnixNano(), ext)
	path := filepath.Join(dir, filename)
	if _, err := file.Save(path); err != nil {
		return "", err
	}
	return "/" + filepath.ToSlash(filepath.Join("workspace", subDir, filename)), nil
}

// RemoveWorkspaceFile 删除 workspace 下文件（路径穿越防护）
func RemoveWorkspaceFile(url string) error {
	rel := strings.TrimPrefix(url, "/workspace/")
	if rel == "" || strings.Contains(rel, "..") {
		return errors.New("非法文件路径")
	}
	abs := filepath.Join("workspace", rel)
	if _, err := os.Stat(abs); os.IsNotExist(err) {
		return nil
	}
	return os.Remove(abs)
}