package repository

import (
	"context"
	"fmt"
	"go.mongodb.org/mongo-driver/bson"
	"log"
	"penahub.gitlab.yandexcloud.net/pena-services/customer/internal/fields"

	"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"
	"go.uber.org/zap"
	"penahub.gitlab.yandexcloud.net/pena-services/customer/internal/dto"
	"penahub.gitlab.yandexcloud.net/pena-services/customer/internal/errors"
	"penahub.gitlab.yandexcloud.net/pena-services/customer/internal/models"
	mongoWrapper "penahub.gitlab.yandexcloud.net/pena-services/customer/pkg/mongo"
)

type HistoryRepositoryDeps struct {
	Logger  *zap.Logger
	MongoDB *mongo.Collection
}

type HistoryRepository struct {
	logger  *zap.Logger
	mongoDB *mongo.Collection
}

func NewHistoryRepository(deps HistoryRepositoryDeps) *HistoryRepository {
	if deps.Logger == nil {
		log.Panicln("logger is nil on <NewHistoryRepository>")
	}

	if deps.MongoDB == nil {
		log.Panicln("mongodb is nil on <NewHistoryRepository>")
	}

	return &HistoryRepository{
		logger:  deps.Logger,
		mongoDB: deps.MongoDB,
	}
}

func (receiver *HistoryRepository) Insert(ctx context.Context, history *models.History) (*models.History, errors.Error) {
	result, err := receiver.mongoDB.InsertOne(ctx, history.Sanitize())
	if err != nil {
		receiver.logger.Error("failed to insert history on <Insert> of <HistoryRepository>",
			zap.Any("history", history),
			zap.Error(err),
		)

		return nil, errors.New(
			fmt.Errorf("failed to insert history on <Insert> of <HistoryRepository>: %w", err),
			errors.ErrInternalError,
		)
	}

	insertedID := result.InsertedID.(primitive.ObjectID).Hex()
	history.ID = insertedID

	return history, nil
}

func (receiver *HistoryRepository) FindMany(ctx context.Context, dto *dto.GetHistories) ([]models.History, errors.Error) {
	findOptions := options.Find()

	findOptions.SetSkip((dto.Pagination.Page - 1) * dto.Pagination.Limit)
	findOptions.SetLimit(dto.Pagination.Limit)
	findOptions.SetSort(bson.D{{
		Key: "createdAt", Value: -1,
	}})

	histories, err := mongoWrapper.Find[models.History](ctx, &mongoWrapper.RequestSettings{
		Driver:  receiver.mongoDB,
		Options: findOptions,
		Filter:  dto.BSON(),
	})
	if err != nil {
		receiver.logger.Error("failed to find many histories on <FindMany> of <HistoryRepository>",
			zap.Int64("page", dto.Pagination.Page),
			zap.Int64("limit", dto.Pagination.Limit),
			zap.Int64("skip", (dto.Pagination.Page-1)*dto.Pagination.Limit),
			zap.Error(err),
		)

		return nil, errors.New(
			fmt.Errorf("failed to find many histories on <FindMany> of <HistoryRepository>: %w", err),
			errors.ErrInternalError,
		)
	}

	return histories, nil
}

func (receiver *HistoryRepository) CountAll(ctx context.Context, dto *dto.GetHistories) (int64, errors.Error) {
	count, err := receiver.mongoDB.CountDocuments(ctx, dto.BSON())
	if err != nil {
		receiver.logger.Error("failed to count all documents on <CountAll> of <HistoryRepository>",
			zap.Error(err),
		)

		return 0, errors.New(
			fmt.Errorf("failed to count all documents on <CountAll> of <HistoryRepository>: %w", err),
			errors.ErrInternalError,
		)
	}

	return count, nil
}

// TODO:tests
// GetRecentTariffs method for processing a user request with data aggregation with a limit of 100 sorted in descending order
func (receiver *HistoryRepository) GetRecentTariffs(ctx context.Context, userID string) ([]string, errors.Error) {
	var result []struct {
		ID string `bson:"tariffID"`
	}
	filter := bson.D{
		{fields.History.UserID, userID},
		{fields.History.IsDeleted, false},
	}
	pipeline := mongo.Pipeline{
		{{"$match", filter}},
		{{"$unwind", "$rawDetails"}},
		{{"$match", bson.D{{"rawDetails.Key", "tariffs"}}}},
		{{"$unwind", "$rawDetails.Value"}},
		{{"$group", bson.D{{"_id", "$rawDetails.Value.Key.id"}}}},
		{{"$sort", bson.D{{"createdAt", -1}}}}, // -1 specifies descending order
		{{"$limit", 100}},
	}
	cursor, err := receiver.mongoDB.Aggregate(ctx, pipeline)
	if err != nil {
		receiver.logger.Error("failed to get recent tariffs on <GetRecentTariffs> of <HistoryRepository>",
			zap.String("userId", userID),
			zap.Error(err),
		)
		return nil, errors.New(
			fmt.Errorf("failed to get recent tariffs on <GetRecentTariffs> of <HistoryRepository>: %w", err),
			errors.ErrInternalError,
		)
	}

	if err := cursor.All(ctx, &result); err != nil {
		receiver.logger.Error("failed to decode recent tariffs on <GetRecentTariffs> of <HistoryRepository>",
			zap.String("userId", userID),
			zap.Error(err),
		)
		return nil, errors.New(
			fmt.Errorf("failed to decode recent tariffs on <GetRecentTariffs> of <HistoryRepository>: %w", err),
			errors.ErrInternalError,
		)
	}
	tariffs := make([]string, len(result))
	for i, item := range result {
		tariffs[i] = item.ID
	}
	return tariffs, nil
}