package hevctaskmod

import (
	"fmt"
	"strings"
	"time"
	"unicode/utf8"

	"91porn-server/common/db"
	"91porn-server/common/log"
	"91porn-server/models"

	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/primitive"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)

const (
	table          = models.HevcTask
	maxErrorMsgLen = 2048
)

var mdb *db.MongoDB

func coll(t *db.MongoTool) *db.MongoTool {
	if t == nil {
		return mdb.Coll(table)
	}
	return t.Coll(table)
}

func Init() {
	mdb = db.Init(table)
	initIndex()
}

func initIndex() {
	indexes := []mongo.IndexModel{
		{
			Keys:    bson.D{{Key: "videoId", Value: 1}},
			Options: options.Index().SetUnique(true),
		},
		{
			Keys: bson.D{{Key: "status", Value: 1}, {Key: "updatedAt", Value: -1}},
		},
	}
	if _, err := coll(nil).CreateIndex(indexes); err != nil {
		panic(fmt.Sprintf("%s model set index err ==>[%+v]", table, err))
	}
}

// Upsert 按视频 ID 写入或更新一条转码任务。
func Upsert(videoID primitive.ObjectID, videoName, submitURL, fileID, h265URL string, status H265TaskStatus) error {
	return UpsertWithError(videoID, videoName, submitURL, fileID, h265URL, status, "")
}

// UpsertWithError 更新转码任务并记录最近一次错误。
func UpsertWithError(videoID primitive.ObjectID, videoName, submitURL, fileID, h265URL string, status H265TaskStatus, errorMsg string) error {
	now := time.Now()
	set := bson.M{
		"videoName": videoName,
		"submitUrl": submitURL,
		"status":    status,
		"updatedAt": now,
	}
	unset := bson.M{}
	if fileID != "" {
		set["fileId"] = fileID
	}
	if h265URL != "" {
		set["h265Url"] = h265URL
	}
	errorMsg = truncateErrorMsg(errorMsg)
	if errorMsg != "" {
		set["errorMsg"] = errorMsg
	} else {
		unset["errorMsg"] = ""
	}
	update := bson.M{
		"$set":         set,
		"$setOnInsert": bson.M{"videoId": videoID, "createdAt": now},
	}
	if len(unset) > 0 {
		update["$unset"] = unset
	}
	if _, err := coll(nil).UpsertOne(bson.M{"videoId": videoID}, update); err != nil {
		log.Warn("H265 task upsert failed", log.Any("videoId", videoID), log.E(err))
		return err
	}
	return nil
}

func truncateErrorMsg(errorMsg string) string {
	errorMsg = strings.TrimSpace(errorMsg)
	if len(errorMsg) <= maxErrorMsgLen {
		return errorMsg
	}
	cut := maxErrorMsgLen
	for cut > 0 && !utf8.ValidString(errorMsg[:cut]) {
		cut--
	}
	return errorMsg[:cut]
}

// UpdateStatus 只更新已有任务的状态。
func UpdateStatus(videoID primitive.ObjectID, status H265TaskStatus) error {
	if _, err := coll(nil).UpdateOne(bson.M{"videoId": videoID}, bson.M{"$set": bson.M{
		"status":    status,
		"updatedAt": time.Now(),
	}}); err != nil {
		log.Warn("H265 task status update failed", log.Any("videoId", videoID), log.E(err))
		return err
	}
	return nil
}