package handler

import (
	"fmt"
	"math/rand"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"

	"soul-api/internal/config"
	"soul-api/internal/oss"

	"github.com/gin-gonic/gin"
)
const maxUploadBytes = 5 * 1024 * 1024 // 5MB
var allowedTypes = map[string]bool{"image/jpeg": true, "image/png": true, "image/gif": true, "image/webp": true}

// UploadPost POST /api/upload 上传图片（表单 file）
// 若管理端已配置 OSS，优先上传到 OSS；OSS 失败或未配置时回退本地磁盘（容灾）
func UploadPost(c *gin.Context) {
	file, err := c.FormFile("file")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"success": false, "error": "请选择要上传的文件"})
		return
	}
	if file.Size > maxUploadBytes {
		c.JSON(http.StatusBadRequest, gin.H{"success": false, "error": "文件大小不能超过5MB"})
		return
	}
	ct := file.Header.Get("Content-Type")
	if !allowedTypes[ct] && !strings.HasPrefix(ct, "image/") {
		c.JSON(http.StatusBadRequest, gin.H{"success": false, "error": "仅支持图片格式"})
		return
	}
	ext := filepath.Ext(file.Filename)
	if ext == "" {
		ext = ".jpg"
	}
	folder := c.PostForm("folder")
	if folder == "" {
		folder = "avatars"
	}
	name := fmt.Sprintf("%d_%s%s", time.Now().UnixNano(), randomStrUpload(6), ext)
	objectKey := filepath.ToSlash(filepath.Join("uploads", folder, name))

	// 优先尝试 OSS（已配置时）
	if oss.IsEnabled() {
		f, err := file.Open()
		if err == nil {
			url, uploadErr := oss.Upload(objectKey, f)
			_ = f.Close()
			if uploadErr == nil && url != "" {
				c.JSON(http.StatusOK, gin.H{"success": true, "url": url, "data": gin.H{"url": url, "fileName": name, "size": file.Size, "type": ct}})
				return
			}
			// OSS 失败，回退本地（容灾）
		}
	}

	// 本地磁盘存储（OSS 未配置或失败时）
	uploadDir := config.Get().UploadDir
	if uploadDir == "" {
		uploadDir = "uploads"
	}
	dir := filepath.Join(uploadDir, folder)
	_ = os.MkdirAll(dir, 0755)
	dst := filepath.Join(dir, name)
	if err := c.SaveUploadedFile(file, dst); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"success": false, "error": "保存失败"})
		return
	}
	relPath := "/uploads/" + filepath.ToSlash(filepath.Join(folder, name))
	fullURL := relPath
	if cfg := config.Get(); cfg != nil && cfg.BaseURL != "" {
		fullURL = cfg.BaseURLJoin(relPath)
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "url": fullURL, "data": gin.H{"url": fullURL, "fileName": name, "size": file.Size, "type": ct}})
}

func randomStrUpload(n int) string {
	const letters = "abcdefghijklmnopqrstuvwxyz0123456789"
	b := make([]byte, n)
	for i := range b {
		b[i] = letters[rand.Intn(len(letters))]
	}
	return string(b)
}

// UploadDelete DELETE /api/upload
// path 支持：/uploads/xxx（本地）或 https://bucket.oss-xxx.aliyuncs.com/uploads/xxx（OSS）
func UploadDelete(c *gin.Context) {
	path := c.Query("path")
	if path == "" {
		c.JSON(http.StatusBadRequest, gin.H{"success": false, "error": "请指定 path"})
		return
	}
	// OSS 公网 URL：从 OSS 删除
	if oss.IsOSSURL(path) {
		objectKey := oss.ParseObjectKeyFromURL(path)
		if objectKey != "" {
			if err := oss.Delete(objectKey); err != nil {
				c.JSON(http.StatusOK, gin.H{"success": false, "error": "OSS 删除失败"})
				return
			}
			c.JSON(http.StatusOK, gin.H{"success": true, "message": "删除成功"})
			return
		}
	}
	// 本地路径：支持 /uploads/xxx、uploads/xxx 或含 /uploads/ 的完整 URL
	if idx := strings.Index(path, "/uploads/"); idx >= 0 {
		path = path[idx+1:] // 从 uploads/ 开始
	}
	rel := strings.TrimPrefix(path, "/uploads/")
	rel = strings.TrimPrefix(rel, "uploads/")
	if rel == "" || strings.Contains(rel, "..") {
		c.JSON(http.StatusForbidden, gin.H{"success": false, "error": "无权限删除此文件"})
		return
	}
	uploadDir := config.Get().UploadDir
	if uploadDir == "" {
		uploadDir = "uploads"
	}
	fullPath := filepath.Join(uploadDir, filepath.FromSlash(rel))
	if err := os.Remove(fullPath); err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "文件不存在或删除失败"})
		return
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "message": "删除成功"})
}