package postgres

import (
	"context"
	"errors"

	errors2 "git.dragse.it/anthrove/otter-space-sdk/pkg/errors"
	"git.dragse.it/anthrove/otter-space-sdk/pkg/models"
	log "github.com/sirupsen/logrus"
	"gorm.io/gorm"
)

func CreateUser(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID) error {

	if anthroveUserID == "" {
		return &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDIsEmpty}
	}

	if len(anthroveUserID) != 25 {
		return &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDToShort}
	}

	user := models.User{
		BaseModel: models.BaseModel[models.AnthroveUserID]{
			ID: anthroveUserID,
		},
	}

	result := db.WithContext(ctx).FirstOrCreate(&user)
	if result.Error != nil {
		if errors.Is(result.Error, gorm.ErrDuplicatedKey) {
			return &errors2.EntityAlreadyExists{}
		}
		return result.Error
	}

	return nil
}

func CreateUserWithRelationToSource(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID, sourceID models.AnthroveSourceID, accountId string, accountUsername string) error {

	if anthroveUserID == "" {
		return &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDIsEmpty}
	}

	if len(anthroveUserID) != 25 {
		return &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDToShort}
	}

	if accountId == "" {
		return &errors2.EntityValidationFailed{Reason: "accountID cannot be empty"}
	}

	if accountUsername == "" {
		return &errors2.EntityValidationFailed{Reason: "accountUsername cannot be empty"}
	}

	err := CreateUser(ctx, db, anthroveUserID)
	if err != nil {
		return err
	}

	source := models.Source{
		BaseModel: models.BaseModel[models.AnthroveSourceID]{ID: sourceID},
	}

	result := db.WithContext(ctx).Where(&source).First(&source)
	if result.Error != nil {
		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
			return &errors2.NoDataFound{}
		}
		return result.Error
	}

	userSource := models.UserSource{
		User:            models.User{BaseModel: models.BaseModel[models.AnthroveUserID]{ID: anthroveUserID}},
		SourceID:        string(source.ID),
		AccountUsername: accountUsername,
		AccountID:       accountId,
		UserID:          string(anthroveUserID),
	}

	result = db.WithContext(ctx).FirstOrCreate(&userSource)
	if result.Error != nil {
		return errors.Join(result.Error, &errors2.NoRelationCreated{})
	}

	if result.RowsAffected == 0 {
		return &errors2.NoDataWritten{}
	}

	log.WithFields(log.Fields{
		"anthrove_user_id": anthroveUserID,
		"source_id":        sourceID,
		"account_username": accountUsername,
		"account_id":       accountId,
	}).Trace("database: created user-source relationship")

	return nil
}

func GetUserFavoritesCount(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID) (int64, error) {
	var count int64

	if anthroveUserID == "" {
		return 0, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDIsEmpty}
	}

	if len(anthroveUserID) != 25 {
		return 0, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDToShort}
	}

	result := db.WithContext(ctx).Model(&models.UserFavorites{}).Where("user_id = ?", string(anthroveUserID)).Count(&count)
	if result.Error != nil {
		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
			return 0, &errors2.NoDataFound{}
		}
		return 0, result.Error
	}

	log.WithFields(log.Fields{
		"anthrove_user_id":        anthroveUserID,
		"anthrove_user_fav_count": count,
	}).Trace("database: got user favorite count")

	return count, nil
}

func GetUserSourceLinks(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID) (map[string]models.UserSource, error) {
	var userSources []models.UserSource
	userSourceMap := make(map[string]models.UserSource)

	if anthroveUserID == "" {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDIsEmpty}
	}

	if len(anthroveUserID) != 25 {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDToShort}
	}

	result := db.WithContext(ctx).Model(&models.UserSource{}).Where("user_id = ?", string(anthroveUserID)).Find(&userSources)
	if result.Error != nil {
		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
			return nil, &errors2.NoDataFound{}
		}
		return nil, result.Error
	}

	for _, userSource := range userSources {
		var source models.Source
		result = db.WithContext(ctx).Model(&models.Source{}).Where("id = ?", userSource.SourceID).First(&source)
		if result.Error != nil {
			if errors.Is(result.Error, gorm.ErrRecordNotFound) {
				return nil, &errors2.NoDataFound{}
			}
			return nil, result.Error
		}

		userSourceMap[source.DisplayName] = models.UserSource{
			UserID:          userSource.AccountID,
			AccountUsername: userSource.AccountUsername,
			Source: models.Source{
				DisplayName: source.DisplayName,
				Domain:      source.Domain,
				Icon:        source.Icon,
			},
		}
	}

	log.WithFields(log.Fields{
		"anthrove_user_id": anthroveUserID,
	}).Trace("database: got user source link")

	return userSourceMap, nil
}

func GetUserSourceBySourceID(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID, sourceID models.AnthroveSourceID) (map[string]models.UserSource, error) {
	var userSources []models.UserSource
	userSourceMap := make(map[string]models.UserSource)

	if anthroveUserID == "" {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDIsEmpty}
	}

	if len(anthroveUserID) != 25 {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDToShort}
	}

	if sourceID == "" {
		return nil, &errors2.EntityValidationFailed{Reason: "sourceID cannot be empty"}
	}

	if len(sourceID) != 25 {
		return nil, &errors2.EntityValidationFailed{Reason: "sourceID needs to be 25 characters long"}
	}

	result := db.WithContext(ctx).Model(&models.UserSource{}).InnerJoins("Source", db.Where("id = ?", sourceID)).Where("user_id = ?", string(anthroveUserID)).First(&userSources)
	if result.Error != nil {
		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
			return nil, &errors2.NoDataFound{}
		}
		return nil, result.Error
	}

	for _, userSource := range userSources {
		var source models.Source
		result = db.WithContext(ctx).Model(&models.Source{}).Where("id = ?", userSource.SourceID).First(&source)
		if result.Error != nil {
			if errors.Is(result.Error, gorm.ErrRecordNotFound) {
				return nil, &errors2.NoDataFound{}
			}
			return nil, result.Error
		}

		userSourceMap[source.DisplayName] = models.UserSource{
			UserID:          userSource.AccountID,
			AccountUsername: userSource.AccountUsername,
			Source: models.Source{
				DisplayName: source.DisplayName,
				Domain:      source.Domain,
				Icon:        source.Icon,
			},
		}
	}

	log.WithFields(log.Fields{
		"anthrove_user_id": anthroveUserID,
		"source_id":        sourceID,
	}).Trace("database: got specified user source link")

	return userSourceMap, nil
}

func GetAllAnthroveUserIDs(ctx context.Context, db *gorm.DB) ([]models.AnthroveUserID, error) {
	var users []models.User
	var userIDs []models.AnthroveUserID

	result := db.WithContext(ctx).Model(&models.User{}).Find(&users)
	if result.Error != nil {
		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
			return nil, &errors2.NoDataFound{}
		}
		return nil, result.Error
	}

	for _, user := range users {
		userIDs = append(userIDs, user.ID)
	}

	log.WithFields(log.Fields{
		"anthrove_user_id_count": len(userIDs),
	}).Trace("database: got all anthrove user IDs")

	return userIDs, nil
}

func GetUserFavoriteWithPagination(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID, skip int, limit int) (*models.FavoriteList, error) {
	var userFavorites []models.UserFavorites
	var favoritePosts []models.Post

	if anthroveUserID == "" {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDIsEmpty}
	}

	if len(anthroveUserID) != 25 {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDToShort}
	}

	err := db.WithContext(ctx).Model(&models.UserFavorites{}).Where("user_id = ?", string(anthroveUserID)).Offset(skip).Limit(limit).Find(&userFavorites).Error
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, &errors2.NoDataFound{}
		}
		return nil, err
	}

	for _, userFavorite := range userFavorites {
		var post models.Post
		err = db.WithContext(ctx).Model(&models.Post{}).Where("id = ?", userFavorite.PostID).First(&post).Error
		if err != nil {
			if errors.Is(err, gorm.ErrRecordNotFound) {
				return nil, &errors2.NoDataFound{}
			}
			return nil, err
		}

		favoritePosts = append(favoritePosts,
			models.Post{
				BaseModel: models.BaseModel[models.AnthrovePostID]{ID: post.ID},
				Rating:    post.Rating,
			})
	}

	log.WithFields(log.Fields{
		"anthrove_user_id":        anthroveUserID,
		"anthrove_user_fav_count": len(favoritePosts),
	}).Trace("database: got all anthrove user favorites")

	return &models.FavoriteList{Posts: favoritePosts}, nil
}

func GetUserTagWitRelationToFavedPosts(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID) ([]models.TagsWithFrequency, error) {
	var userFavorites []models.UserFavorites

	if anthroveUserID == "" {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDIsEmpty}
	}

	if len(anthroveUserID) != 25 {
		return nil, &errors2.EntityValidationFailed{Reason: errors2.AnthroveUserIDToShort}
	}

	result := db.WithContext(ctx).Where("user_id = ?", string(anthroveUserID)).Find(&userFavorites)
	if result.Error != nil {
		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
			return nil, &errors2.NoDataFound{}
		}
		return nil, result.Error
	}

	tagFrequency := make(map[struct {
		name     string
		typeName string
	}]int)

	for _, userFavorite := range userFavorites {
		var post models.Post
		result = db.WithContext(ctx).Preload("Tags").First(&post, "id = ?", userFavorite.PostID)
		if result.Error != nil {
			if errors.Is(result.Error, gorm.ErrRecordNotFound) {
				return nil, &errors2.NoDataFound{}
			}
			return nil, result.Error
		}

		for _, tag := range post.Tags {
			tagFrequency[struct {
				name     string
				typeName string
			}{name: tag.Name, typeName: string(tag.Type)}]++
		}
	}

	var tagsWithFrequency []models.TagsWithFrequency
	for data, frequency := range tagFrequency {
		tagsWithFrequency = append(tagsWithFrequency, models.TagsWithFrequency{
			Frequency: int64(frequency),
			Tags: models.Tag{
				Name: data.name,
				Type: models.TagType(data.typeName),
			},
		})
	}

	log.WithFields(log.Fields{
		"anthrove_user_id": anthroveUserID,
		"tag_amount":       len(tagsWithFrequency),
	}).Trace("database: got user tag node with relation to faved posts")

	return tagsWithFrequency, nil
}