package repository

import (
	"context"
	"errors"
	"time"

	"code.30cm.net/digimon/app-cloudep-product-service/pkg/domain"
	"code.30cm.net/digimon/app-cloudep-product-service/pkg/domain/entity"
	"code.30cm.net/digimon/app-cloudep-product-service/pkg/domain/repository"
	mgo "code.30cm.net/digimon/library-go/mongo"
	"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"

	"github.com/zeromicro/go-zero/core/stores/cache"
	"github.com/zeromicro/go-zero/core/stores/mon"
)

type ProductRepositoryParam struct {
	Conf      *mgo.Conf
	CacheConf cache.CacheConf
	DBOpts    []mon.Option
	CacheOpts []cache.Option
}

type ProductRepository struct {
	DB mgo.DocumentDBWithCacheUseCase
}

func NewProductRepository(param ProductRepositoryParam) repository.ProductRepository {
	e := entity.Product{}
	documentDB, err := mgo.MustDocumentDBWithCache(
		param.Conf,
		e.CollectionName(),
		param.CacheConf,
		param.DBOpts,
		param.CacheOpts,
	)
	if err != nil {
		panic(err)
	}

	return &ProductRepository{
		DB: documentDB,
	}
}

func (repo *ProductRepository) Insert(ctx context.Context, data *entity.Product) error {
	if data.ID.IsZero() {
		now := time.Now().UTC().UnixNano()
		data.ID = primitive.NewObjectID()
		data.CreatedAt = now
		data.UpdatedAt = now
	}
	rk := domain.GetProductRK(data.ID.Hex())
	_, err := repo.DB.InsertOne(ctx, rk, data)

	return err
}

func (repo *ProductRepository) FindOneByID(ctx context.Context, id string) (*entity.Product, error) {
	oid, err := primitive.ObjectIDFromHex(id)
	if err != nil {
		return nil, err
	}

	var result *entity.Product
	err = repo.DB.FindOne(ctx, domain.GetProductRK(id), &result, bson.M{"_id": oid})
	switch {
	case err == nil:
		return result, nil
	case errors.Is(err, mon.ErrNotFound):
		return nil, ErrNotFound
	default:
		return nil, err
	}
}

func (repo *ProductRepository) FindOneBySlug(ctx context.Context, slug string) (*entity.Product, error) {
	var result *entity.Product
	err := repo.DB.FindOne(ctx, domain.GetProductRK(slug), &result, bson.M{"slug": slug})
	switch {
	case err == nil:
		return result, nil
	case errors.Is(err, mon.ErrNotFound):
		return nil, ErrNotFound
	default:
		return nil, err
	}
}

func (repo *ProductRepository) Update(ctx context.Context, productID string, data *repository.ProductUpdateParams) (*mongo.UpdateResult, error) {
	item, err := repo.FindOneByID(ctx, productID)
	if err != nil {
		return nil, err
	}
	now := time.Now().UTC().UnixNano()
	// 動態構建更新內容
	updateFields := bson.M{
		"updated_at": now, // 確保 `updateAt` 總是更新
	}
	if data.Title != nil {
		updateFields["title"] = *data.Title
	}
	if data.IsPublished != nil {
		updateFields["is_published"] = *data.IsPublished
	}
	if data.StartTime != nil {
		updateFields["start_time"] = *data.StartTime
	}
	if data.EndTime != nil {
		updateFields["end_time"] = *data.EndTime
	}
	if data.ShortDescription != "" {
		updateFields["short_description"] = data.ShortDescription
	}
	if data.Category != nil {
		updateFields["category"] = *data.Category
	}
	if data.Details != nil {
		updateFields["details"] = *data.Details
	}
	if data.ShortTitle != nil {
		updateFields["short_title"] = *data.ShortTitle
	}
	if data.Slug != nil {
		updateFields["slug"] = *data.Slug
	}
	if data.Amount != nil {
		updateFields["amount"] = *data.Amount
	}
	if len(data.Media) > 0 {
		updateFields["media"] = data.Media
	}
	if len(data.Media) > 0 {
		updateFields["media"] = data.Media
	}
	if len(data.CustomFields) > 0 {
		updateFields["custom_fields"] = data.CustomFields
	}

	oid, err := primitive.ObjectIDFromHex(productID)
	if err != nil {
		return nil, ErrInvalidObjectID
	}

	// 執行更新
	rk := domain.GetProductRK(productID)
	res, err := repo.DB.UpdateOne(ctx, rk, bson.M{"_id": oid}, bson.M{"$set": updateFields})
	if err != nil {
		return nil, err
	}
	_ = repo.DB.DelCache(ctx, domain.GetProductRK(*item.Slug))

	return res, err
}

func (repo *ProductRepository) Delete(ctx context.Context, id string) error {
	item, err := repo.FindOneByID(ctx, id)
	if err != nil {
		return err
	}

	oid, err := primitive.ObjectIDFromHex(id)
	if err != nil {
		return ErrInvalidObjectID
	}

	filter := bson.M{"_id": oid}
	_, err = repo.DB.DeleteOne(ctx, domain.GetProductRK(id), filter)
	if err != nil {
		return err
	}

	_ = repo.DB.DelCache(ctx, domain.GetProductRK(*item.Slug))

	return nil
}

func (repo *ProductRepository) ListProduct(ctx context.Context, params *repository.ProductQueryParams) ([]*entity.Product, int64, error) {
	// 構建查詢過濾器
	filter := bson.M{}
	if params.UID != nil && *params.UID != "" {
		filter["uid"] = *params.UID
	}
	if params.IsPublished != nil {
		filter["is_published"] = *params.IsPublished
	}
	if params.Category != nil {
		filter["category"] = *params.Category
	}
	if params.StartTime != nil {
		filter["start_time"] = bson.M{"$gte": *params.StartTime} // 篩選開始時間在指定時間之後的專案
	}
	if params.EndTime != nil {
		filter["end_time"] = bson.M{"$lte": *params.EndTime} // 篩選結束時間在指定時間之前的專案
	}
	if params.Slug != nil && *params.Slug != "" {
		filter["slug"] = *params.Slug
	}

	// 設置排序選項
	opts := options.Find().SetSkip((params.PageIndex - 1) * params.PageSize).SetLimit(params.PageSize)
	opts.SetSort(bson.D{{Key: "updated_at", Value: -1}})

	// 查詢符合條件的總數
	count, err := repo.DB.GetClient().CountDocuments(ctx, filter)
	if err != nil {
		return nil, 0, err
	}

	// 執行查詢並獲取結果
	var products []*entity.Product
	err = repo.DB.GetClient().Find(ctx, &products, filter, opts)
	if err != nil {
		return nil, 0, err
	}

	return products, count, nil
}

func (repo *ProductRepository) Transaction(
	ctx context.Context,
	fn func(sessCtx mongo.SessionContext) (any, error),
	opts ...*options.TransactionOptions) error {
	// 獲取資料庫連接
	db := repo.DB.GetClient().Database()

	// 使用 MongoDB 的會話進行操作
	return db.Client().UseSession(ctx, func(sessionCtx mongo.SessionContext) error {
		// 開始交易，支持可選的 TransactionOptions
		if err := sessionCtx.StartTransaction(opts...); err != nil {
			return err
		}

		// 執行用戶提供的交易函數
		result, err := fn(sessionCtx)
		if err != nil {
			// 若發生錯誤則中止交易
			if abortErr := sessionCtx.AbortTransaction(ctx); abortErr != nil {
				return abortErr
			}

			return err
		}

		// 提交交易
		if err := sessionCtx.CommitTransaction(ctx); err != nil {
			// 若提交失敗則中止交易
			if abortErr := sessionCtx.AbortTransaction(ctx); abortErr != nil {
				return abortErr
			}

			return err
		}

		// 返回交易執行結果
		_ = result // 結果未使用，保留擴展可能

		return nil
	})
}

func (repo *ProductRepository) Index20250317001UP(ctx context.Context) (*mongo.Cursor, error) {
	// 等價於 db.account.createIndex({"create_at": 1})
	repo.DB.PopulateIndex(ctx, "uid", 1, false)
	repo.DB.PopulateIndex(ctx, "slug", 1, true)
	repo.DB.PopulateIndex(ctx, "category", 1, false)

	return repo.DB.GetClient().Indexes().List(ctx)
}