package repositories

import (
	"learnsteam/cslms-api/internal/models"

	"gorm.io/gorm"
)

type paperQuizRepository struct {
	DB *gorm.DB
}

func NewPaperQuizRepository(db *gorm.DB) PaperQuizRepository {
	return &paperQuizRepository{
		DB: db,
	}
}

type PaperQuizRepository interface {
	List(int64, int, int) (*[]models.PaperQuiz, error)
	Total(int64) (int64, error)

	Find(int64) (*models.PaperQuiz, error)
	Update(*models.PaperQuiz) (*models.PaperQuiz, error)
	Delete(int64) error
	SumScore(int64) (float32, error)
}

func (r *paperQuizRepository) List(paper_id int64, page int, limit int) (*[]models.PaperQuiz, error) {
	var rows *[]models.PaperQuiz
	var err error
	offset := limit * (page - 1)
	if paper_id > 0 {
		err = r.DB.Offset(offset).Limit(limit).Order("vol_no ASC").Where("user_quiz_paper_id = ?", paper_id).Find(&rows).Error
	} else {
		err = r.DB.Offset(offset).Limit(limit).Find(&rows).Error
	}
	return rows, err
}

func (r *paperQuizRepository) Total(paper_id int64) (int64, error) {
	var total int64
	var err error
	if paper_id > 0 {
		err = r.DB.Model(&models.PaperQuiz{}).Where("user_quiz_paper_id = ?", paper_id).Count(&total).Error
	} else {
		err = r.DB.Model(&models.PaperQuiz{}).Count(&total).Error
	}

	return total, err
}

func (r *paperQuizRepository) Find(id int64) (*models.PaperQuiz, error) {
	var row *models.PaperQuiz
	err := r.DB.Where("id = ?", id).First(&row).Error
	return row, err
}

func (r *paperQuizRepository) Update(quiz *models.PaperQuiz) (*models.PaperQuiz, error) {
	var row *models.PaperQuiz
	if err := r.DB.Where("id=?", quiz.ID).First(&row).Error; err != nil {
		return nil, err
	}

	err := r.DB.Model(&row).Select("*").Updates(&quiz).Error
	return row, err
}

func (r *paperQuizRepository) Delete(id int64) error {
	var row *models.PaperQuiz
	if err := r.DB.Where("id=?", id).First(&row).Error; err != nil {
		return err
	}
	err := r.DB.Delete(&row).Error
	return err
}

func (r *paperQuizRepository) SumScore(paper_id int64) (float32, error) {
	var result struct {
		Score float32
	}

	if err := r.DB.Model(&models.PaperQuiz{}).Select("SUM(score) AS score").
		Where("user_quiz_paper_id = ?", paper_id).
		Scan(&result).Error; err != nil {
		return 0, err
	}
	return result.Score, nil
}