package repository

import (
	"context"
	"strings"

	"haixun-backend/internal/library/clock"
	app "haixun-backend/internal/library/errors"
	"haixun-backend/internal/library/errors/code"
	libmongo "haixun-backend/internal/library/mongo"
	"haixun-backend/internal/model/content_matrix/domain/entity"
	domrepo "haixun-backend/internal/model/content_matrix/domain/repository"

	"github.com/google/uuid"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)

type mongoRepository struct {
	collection *mongo.Collection
}

func NewMongoRepository(db *mongo.Database) domrepo.Repository {
	if db == nil {
		return &mongoRepository{}
	}
	return &mongoRepository{collection: db.Collection(entity.CollectionName)}
}

func (r *mongoRepository) EnsureIndexes(ctx context.Context) error {
	if r.collection == nil {
		return nil
	}
	return libmongo.EnsureIndexes(ctx, r.collection, []mongo.IndexModel{
		{
			Keys:    bson.D{{Key: "tenant_id", Value: 1}, {Key: "owner_uid", Value: 1}, {Key: "brand_id", Value: 1}},
			Options: options.Index().SetUnique(true).SetPartialFilterExpression(bson.M{"brand_id": bson.M{"$gt": ""}})},
		{
			Keys:    bson.D{{Key: "tenant_id", Value: 1}, {Key: "owner_uid", Value: 1}, {Key: "persona_id", Value: 1}},
			Options: options.Index().SetUnique(true).SetPartialFilterExpression(bson.M{"persona_id": bson.M{"$gt": ""}})},
	})
}

func brandOwnerFilter(tenantID, ownerUID, brandID string) bson.M {
	filter := bson.M{
		"tenant_id": tenantID,
		"owner_uid": ownerUID,
	}
	for k, v := range libmongo.BrandScopeFilter(brandID) {
		filter[k] = v
	}
	return filter
}

func (r *mongoRepository) UpsertByBrand(ctx context.Context, matrix *entity.ContentMatrix) (*entity.ContentMatrix, error) {
	if r.collection == nil {
		return nil, app.For(code.Brand).DBUnavailable("Mongo is not configured")
	}
	now := clock.NowUnixNano()
	matrix.UpdateAt = now
	if matrix.CreateAt == 0 {
		matrix.CreateAt = now
	}
	if strings.TrimSpace(matrix.ID) == "" {
		matrix.ID = uuid.NewString()
	}
	filter := brandOwnerFilter(matrix.TenantID, matrix.OwnerUID, matrix.BrandID)
	update := bson.M{
		"$set": bson.M{
			"rows":         matrix.Rows,
			"generated_at": matrix.GeneratedAt,
			"update_at":    matrix.UpdateAt,
			"brand_id":     matrix.BrandID,
		},
		"$setOnInsert": bson.M{
			"_id":       matrix.ID,
			"tenant_id": matrix.TenantID,
			"owner_uid": matrix.OwnerUID,
			"create_at": matrix.CreateAt,
		},
	}
	opts := options.FindOneAndUpdate().SetUpsert(true).SetReturnDocument(options.After)
	var out entity.ContentMatrix
	err := r.collection.FindOneAndUpdate(ctx, filter, update, opts).Decode(&out)
	if err != nil {
		return nil, err
	}
	return &out, nil
}

func (r *mongoRepository) GetByBrand(ctx context.Context, tenantID, ownerUID, brandID string) (*entity.ContentMatrix, error) {
	if r.collection == nil {
		return nil, app.For(code.Brand).DBUnavailable("Mongo is not configured")
	}
	var out entity.ContentMatrix
	err := r.collection.FindOne(ctx, brandOwnerFilter(tenantID, ownerUID, brandID)).Decode(&out)
	if err == mongo.ErrNoDocuments {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	return &out, nil
}