package jobs

import (
	"context"
	"errors"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"time"

	"quyun/v2/app/jobs/args"
	"quyun/v2/database/models"
	"quyun/v2/pkg/consts"
	"quyun/v2/providers/storage"

	"github.com/riverqueue/river"
	log "github.com/sirupsen/logrus"
	"gorm.io/gorm"
)

// @provider(job)
type MediaProcessWorker struct {
	river.WorkerDefaults[args.MediaAssetProcessJob]
	storage *storage.Storage
}

func (j *MediaProcessWorker) Work(ctx context.Context, job *river.Job[args.MediaAssetProcessJob]) error {
	arg := job.Args
	// 1. 获取媒体资源，保证租户隔离。
	tbl, q := models.MediaAssetQuery.QueryContext(ctx)
	q = q.Where(tbl.ID.Eq(arg.AssetID))
	if arg.TenantID > 0 {
		q = q.Where(tbl.TenantID.Eq(arg.TenantID))
	}
	asset, err := q.First()
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			log.Warnf("media asset not found: %d", arg.AssetID)
			return river.JobCancel(err)
		}
		return err
	}

	if asset.Status == consts.MediaAssetStatusReady || asset.Status == consts.MediaAssetStatusDeleted {
		return nil
	}

	// 2. 更新状态为处理中，标识处理已开始。
	_, err = models.MediaAssetQuery.WithContext(ctx).
		Where(models.MediaAssetQuery.ID.Eq(asset.ID)).
		UpdateSimple(
			models.MediaAssetQuery.Status.Value(consts.MediaAssetStatusProcessing),
			models.MediaAssetQuery.UpdatedAt.Value(time.Now()),
		)
	if err != nil {
		return err
	}

	finalStatus := consts.MediaAssetStatusReady

	// 3. 处理视频（FFmpeg，未安装时走模拟流程）。
	if asset.Type == consts.MediaAssetTypeVideo {
		if strings.ToLower(asset.Provider) == "local" {
			localPath := j.storage.Config.LocalPath
			if localPath == "" {
				localPath = "./storage"
			}
			inputFile := filepath.Join(localPath, asset.ObjectKey)
			if _, err := os.Stat(inputFile); err != nil {
				log.Errorf("media file missing: %s, err=%v", inputFile, err)
				finalStatus = consts.MediaAssetStatusFailed
			} else if _, err := exec.LookPath("ffmpeg"); err != nil {
				log.Warn("ffmpeg not found, skipping real transcoding")
			} else {
				outputDir := filepath.Dir(inputFile)
				coverKey := asset.ObjectKey + ".jpg"
				coverFile := filepath.Join(outputDir, filepath.Base(coverKey))

				// 生成封面，作为后续管线的占位输出。
				cmd := exec.CommandContext(
					ctx,
					"ffmpeg",
					"-y",
					"-i",
					inputFile,
					"-ss",
					"00:00:01.000",
					"-vframes",
					"1",
					coverFile,
				)
				if out, err := cmd.CombinedOutput(); err != nil {
					log.Errorf("ffmpeg failed: %s, output: %s", err, string(out))
					finalStatus = consts.MediaAssetStatusFailed
				} else {
					log.Infof("Generated cover: %s", coverFile)
					// TODO: 生成封面资产或写入 meta，由后续管线接管。
				}
			}
		} else {
			log.Warn("non-local provider, skipping ffmpeg processing")
		}
	}

	// 4. 更新最终状态。
	_, err = models.MediaAssetQuery.WithContext(ctx).
		Where(models.MediaAssetQuery.ID.Eq(asset.ID)).
		Updates(&models.MediaAsset{
			Status:    finalStatus,
			UpdatedAt: time.Now(),
		})
	return err
}