package upload

import (
	"errors"
	"mime/multipart"
	"path"
	"strings"
	"time"

	"github.com/google/uuid"
)

var (
	ErrFileEmpty     = errors.New("文件为空")
	ErrFileTooLarge  = errors.New("文件过大")
	ErrFileTypeError = errors.New("文件类型不允许")
)

// OSS 对象存储接口
type OSS interface {
	UploadFile(file *multipart.FileHeader) (string, string, error)
	DeleteFile(key string) error
}

// Config 上传配置
type Config struct {
	Type    string // local, aliyun, tencent, qiniu, minio, aws-s3, huawei-obs, cloudflare-r2
	Path    string
	MaxSize int64
}

// GenerateFileName 生成文件名
func GenerateFileName(originalName string) string {
	ext := path.Ext(originalName)
	name := uuid.New().String()
	return name + ext
}

// GeneratePath 生成存储路径
func GeneratePath(basePath string) string {
	now := time.Now()
	return path.Join(basePath, now.Format("2006/01/02"))
}

// CheckFileSize 检查文件大小
func CheckFileSize(size int64, maxSize int64) error {
	if size > maxSize {
		return ErrFileTooLarge
	}
	return nil
}

// CheckFileType 检查文件类型
func CheckFileType(filename string, allowTypes []string) error {
	ext := strings.ToLower(path.Ext(filename))
	for _, t := range allowTypes {
		if ext == t || t == "*" {
			return nil
		}
	}
	return ErrFileTypeError
}

// DefaultAllowTypes 默认允许的文件类型
var DefaultAllowTypes = []string{
	".jpg", ".jpeg", ".png", ".gif", ".bmp", ".webp",
	".pdf", ".doc", ".docx", ".xls", ".xlsx", ".ppt", ".pptx",
	".txt", ".md", ".json", ".xml", ".csv",
	".zip", ".rar", ".7z", ".tar", ".gz",
	".mp3", ".mp4", ".avi", ".mov", ".wmv",
}