package video

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"os"
	"path/filepath"
	"strings"
	"time"

	common "media/controller/common"
	dto "media/model/dto/video"
	service "media/service/video"

	"gitea.com/red-future/common/beans"
	"github.com/gogf/gf/v2/frame/g"
	"github.com/gogf/gf/v2/net/ghttp"
)

type video struct{}

var Concat = new(video)

// ConcatVideosHandler 视频拼接
// 支持两种入参方式：
//  1. JSON body: {"video_urls":[...], "method":"auto"}
//  2. 文件上传: files 参数（至少2个视频）
func (c *video) ConcatVideosHandler(r *ghttp.Request) {
	ctx := r.Context()
	ctx = context.WithValue(ctx, "user", &beans.User{UserName: "admin"})

	// 优先尝试 JSON body（URL 列表模式）
	body := r.GetBody()
	if len(body) > 0 && body[0] == '{' {
		var req dto.ConcatReq
		if json.Unmarshal(body, &req) == nil && len(req.VideoURLs) >= 2 {
			if req.Method == "" {
				req.Method = "auto"
			}

			tempDir := g.Cfg().MustGet(ctx, "ffmpeg.temp_dir", "resource/temp").String()
			if !filepath.IsAbs(tempDir) {
				absDir, _ := filepath.Abs(tempDir)
				tempDir = absDir
			}
			os.MkdirAll(tempDir, 0755)

			var savePaths []string
			for _, videoURL := range req.VideoURLs {
				savePath, dlErr := downloadFromURL(ctx, videoURL, tempDir)
				if dlErr != nil {
					continue
				}
				savePaths = append(savePaths, savePath)
			}
			if len(savePaths) < 2 {
				cleanupConcat(savePaths)
				r.Response.WriteJson(g.Map{"code": 400, "message": "成功下载的视频不足2个"})
				return
			}

			svcRes, svcErr := service.Concat.Concat(ctx, &service.ConcatReq{
				VideoPaths: savePaths,
				Method:     req.Method,
			})
			cleanupConcat(savePaths)
			if svcErr != nil {
				r.Response.WriteJson(g.Map{"code": 500, "message": "视频拼接失败: " + svcErr.Error()})
				return
			}

			r.Response.WriteJson(g.Map{
				"code":    200,
				"message": "success",
				"data": g.Map{
					"outputPath":  svcRes.OutputPath,
					"fileSize":    svcRes.FileSize,
					"duration":    svcRes.Duration,
					"durationStr": svcRes.DurationStr,
					"methodUsed":  svcRes.MethodUsed,
					"inputFiles":  svcRes.InputFiles,
				},
			})
			return
		}
	}

	// 文件上传模式
	savePaths, err := common.SaveUploadedFiles(r)
	if err != nil || len(savePaths) < 2 {
		r.Response.WriteJson(g.Map{"code": 400, "message": fmt.Sprintf("至少需要2个视频，当前%d个", len(savePaths))})
		return
	}

	svcRes, svcErr := service.Concat.Concat(ctx, &service.ConcatReq{
		VideoPaths: savePaths,
		Method:     r.Get("method", "auto").String(),
	})
	service.CleanupConcat(savePaths)
	if svcErr != nil {
		r.Response.WriteJson(g.Map{"code": 500, "message": "视频拼接失败: " + svcErr.Error()})
		return
	}

	r.Response.ServeFile(svcRes.OutputPath)
	go func(path string) {
		time.Sleep(5 * time.Second)
		os.Remove(path)
	}(svcRes.OutputPath)
}

func downloadFromURL(ctx context.Context, rawURL, tempDir string) (string, error) {
	parsedURL, err := url.Parse(rawURL)
	if err != nil {
		return "", err
	}
	segments := strings.Split(parsedURL.Path, "/")
	fileName := segments[len(segments)-1]
	if fileName == "" {
		fileName = fmt.Sprintf("video_%d.mp4", time.Now().UnixMilli())
	}
	savePath := filepath.Join(tempDir, fmt.Sprintf("%d_%s", time.Now().UnixMilli(), fileName))

	client := &http.Client{Timeout: 10 * time.Minute}
	resp, err := client.Get(rawURL)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return "", fmt.Errorf("HTTP %d", resp.StatusCode)
	}

	out, err := os.Create(savePath)
	if err != nil {
		return "", err
	}
	defer out.Close()

	_, err = io.Copy(out, resp.Body)
	if err != nil {
		os.Remove(savePath)
	}
	return savePath, err
}

func cleanupConcat(paths []string) {
	for _, p := range paths {
		os.Remove(p)
	}
}