package fs

import (
	"ZhenTuLocalPassiveAdapter/config"
	"ZhenTuLocalPassiveAdapter/dto"
	"ZhenTuLocalPassiveAdapter/logger"
	"ZhenTuLocalPassiveAdapter/util"
	"context"
	"fmt"
	"path"
	"sort"
	"time"

	"github.com/aliyun/aliyun-oss-go-sdk/oss"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/codes"
	"go.uber.org/zap"
)

type AliOSSAdapter struct {
	StorageConfig config.StorageConfig
	ossClient     *oss.Client
}

func (a *AliOSSAdapter) getClient() (*oss.Client, error) {
	if a.ossClient == nil {
		client, err := oss.New(
			a.StorageConfig.AliOSS.Endpoint,
			a.StorageConfig.AliOSS.AccessKeyId,
			a.StorageConfig.AliOSS.AccessKeySecret,
		)
		if err != nil {
			return nil, fmt.Errorf("创建阿里云OSS客户端失败: %w", err)
		}
		a.ossClient = client
	}
	return a.ossClient, nil
}

func (a *AliOSSAdapter) GetFileList(ctx context.Context, dirPath string, relDt time.Time) ([]dto.File, error) {
	_, span := tracer.Start(ctx, "GetFileList_alioss")
	defer span.End()

	span.SetAttributes(attribute.String("path", dirPath))
	span.SetAttributes(attribute.String("relativeDate", relDt.Format("2006-01-02")))
	if a.StorageConfig.AliOSS.Bucket == "" {
		span.SetAttributes(attribute.String("error", "未配置阿里云OSS存储桶"))
		span.SetStatus(codes.Error, "未配置阿里云OSS存储桶")
		return nil, fmt.Errorf("未配置阿里云OSS存储桶")
	}

	cacheKey := fmt.Sprintf("%s_%s", dirPath, relDt.Format("2006-01-02"))
	fileListCache := getAliOssFileListCache()
	if cachedFiles, ok := fileListCache.Get(cacheKey); ok {
		logger.Debug("获取已缓存列表", zap.String("cacheKey", cacheKey))
		span.SetAttributes(attribute.Bool("cache.hit", true))
		span.SetAttributes(attribute.Int("file.count", len(cachedFiles)))
		span.SetStatus(codes.Ok, "文件读取成功")
		return cachedFiles, nil
	}

	fileList, hit, shared, err := fileListCache.GetOrLoad(cacheKey, func() ([]dto.File, error) {
		client, err := a.getClient()
		if err != nil {
			return nil, err
		}

		bucket, err := client.Bucket(a.StorageConfig.AliOSS.Bucket)
		if err != nil {
			return nil, fmt.Errorf("获取存储桶失败: %w", err)
		}

		var resultFiles []dto.File
		prefix := path.Join(a.StorageConfig.AliOSS.Prefix, dirPath)
		marker := ""

		for {
			lsRes, err := bucket.ListObjects(
				oss.Prefix(prefix),
				oss.Marker(marker),
				oss.MaxKeys(1000),
			)
			if err != nil {
				return nil, fmt.Errorf("文件列表读取失败: %w", err)
			}

			for _, object := range lsRes.Objects {
				key := object.Key
				if !util.IsVideoFile(path.Base(key)) {
					continue
				}
				startTime, stopTime, err := util.ParseStartStopTime(path.Base(key), relDt)
				if err != nil {
					continue
				}
				if stopTime.IsZero() {
					stopTime = startTime
				}
				if startTime.Equal(stopTime) {
					stopTime = stopTime.Add(time.Second * time.Duration(config.Config.Record.Duration))
				}

				// 生成预签名URL(有效期10分钟)
				signedURL, err := bucket.SignURL(key, oss.HTTPGet, 600)
				if err != nil {
					logger.Error("生成预签名URL失败", zap.Error(err))
					continue
				}

				resultFiles = append(resultFiles, dto.File{
					BasePath:  a.StorageConfig.AliOSS.Bucket,
					Name:      path.Base(key),
					Path:      path.Dir(key),
					Url:       signedURL,
					StartTime: startTime,
					EndTime:   stopTime,
				})
			}

			if !lsRes.IsTruncated {
				break
			}
			marker = lsRes.NextMarker
		}

		sort.Slice(resultFiles, func(i, j int) bool {
			return resultFiles[i].StartTime.Before(resultFiles[j].StartTime)
		})
		return resultFiles, nil
	})
	if err != nil {
		span.SetAttributes(attribute.String("error", err.Error()))
		span.SetStatus(codes.Error, "文件列表读取失败")
		return nil, err
	}

	span.SetAttributes(attribute.Bool("cache.shared", shared))
	span.SetAttributes(attribute.Int("file.count", len(fileList)))
	span.SetStatus(codes.Ok, "文件读取成功")

	if !hit && !shared {
		logger.Debug("缓存文件列表", zap.String("cacheKey", cacheKey))
	}
	return fileList, nil
}