package repository

import (
	"context"
	"database/sql"
	"errors"
	"tailly_back_v2/internal/domain"
	"time"
)

var (
	ErrUserNotFound = errors.New("user not found")
)

type UserRepository interface {
	Create(ctx context.Context, user *domain.User) error
	GetByID(ctx context.Context, id int) (*domain.User, error)
	GetAll(ctx context.Context, id int) ([]*domain.User, error)
	GetByEmail(ctx context.Context, email string) (*domain.User, error)
	GetByConfirmationToken(ctx context.Context, token string) (*domain.User, error)
	Update(ctx context.Context, user *domain.User) error
	Delete(ctx context.Context, id int) error
}

type userRepository struct {
	db *sql.DB
}

func NewUserRepository(db *sql.DB) UserRepository {
	return &userRepository{db: db}
}

func (r *userRepository) Create(ctx context.Context, user *domain.User) error {
	query := `
		INSERT INTO users (username, email, password, email_confirmation_token, created_at, updated_at)
		VALUES ($1, $2, $3, $4, $5, $6)
		RETURNING id
	`

	err := r.db.QueryRowContext(ctx, query,
		user.Username,
		user.Email,
		user.Password,
		user.EmailConfirmationToken,
		user.CreatedAt,
		user.UpdatedAt,
	).Scan(&user.ID)

	return err
}

func (r *userRepository) GetByID(ctx context.Context, id int) (*domain.User, error) {
	query := `
		SELECT id, username, email, password, email_confirmation_token, email_confirmed_at, created_at, updated_at, avatar
		FROM users
		WHERE id = $1
	`

	user := &domain.User{}
	var confirmedAt sql.NullTime

	err := r.db.QueryRowContext(ctx, query, id).Scan(
		&user.ID,
		&user.Username,
		&user.Email,
		&user.Password,
		&user.EmailConfirmationToken,
		&confirmedAt,
		&user.CreatedAt,
		&user.UpdatedAt,
		&user.Avatar,
	)

	if err == sql.ErrNoRows {
		return nil, ErrUserNotFound
	}

	if confirmedAt.Valid {
		user.EmailConfirmedAt = &confirmedAt.Time
	}

	return user, err
}

func (r *userRepository) GetByEmail(ctx context.Context, email string) (*domain.User, error) {
	query := `
		SELECT id, username, email, password, email_confirmation_token, email_confirmed_at, created_at, updated_at, avatar
		FROM users
		WHERE email = $1
	`

	user := &domain.User{}
	var confirmedAt sql.NullTime

	err := r.db.QueryRowContext(ctx, query, email).Scan(
		&user.ID,
		&user.Username,
		&user.Email,
		&user.Password,
		&user.EmailConfirmationToken,
		&confirmedAt,
		&user.CreatedAt,
		&user.UpdatedAt,
		&user.Avatar,
	)

	if err == sql.ErrNoRows {
		return nil, ErrUserNotFound
	}

	if confirmedAt.Valid {
		user.EmailConfirmedAt = &confirmedAt.Time
	}

	return user, err
}

func (r *userRepository) GetByConfirmationToken(ctx context.Context, token string) (*domain.User, error) {
	query := `
		SELECT id, username, email, password, email_confirmation_token, email_confirmed_at, created_at, updated_at, avatar
		FROM users
		WHERE email_confirmation_token = $1
	`

	user := &domain.User{}
	var confirmedAt sql.NullTime

	err := r.db.QueryRowContext(ctx, query, token).Scan(
		&user.ID,
		&user.Username,
		&user.Email,
		&user.Password,
		&user.EmailConfirmationToken,
		&confirmedAt,
		&user.CreatedAt,
		&user.UpdatedAt,
		&user.Avatar,
	)

	if err == sql.ErrNoRows {
		return nil, ErrUserNotFound
	}

	if confirmedAt.Valid {
		user.EmailConfirmedAt = &confirmedAt.Time
	}

	return user, err
}

func (r *userRepository) Update(ctx context.Context, user *domain.User) error {
	query := `
		UPDATE users
		SET username = $1,
			email = $2,
			password = $3,
			email_confirmation_token = $4,
			email_confirmed_at = $5,
			avatar = $6,
			updated_at = $7
		WHERE id = $8
	`

	var confirmedAt interface{}
	if user.EmailConfirmedAt != nil {
		confirmedAt = *user.EmailConfirmedAt
	} else {
		confirmedAt = nil
	}

	_, err := r.db.ExecContext(ctx, query,
		user.Username,
		user.Email,
		user.Password,
		user.EmailConfirmationToken,
		confirmedAt,
		&user.Avatar,
		time.Now(), // Обновляем updated_at
		user.ID,
	)

	return err
}

func (r *userRepository) Delete(ctx context.Context, id int) error {
	query := `DELETE FROM users WHERE id = $1`
	_, err := r.db.ExecContext(ctx, query, id)
	return err
}

func (r *userRepository) GetAll(ctx context.Context, id int) ([]*domain.User, error) {
	query := `
		SELECT id, username, avatar
		FROM users
		WHERE id != $1
	`

	rows, err := r.db.QueryContext(ctx, query, id)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var users []*domain.User
	for rows.Next() {
		user := &domain.User{}
		err := rows.Scan(
			&user.ID,
			&user.Username,
			&user.Avatar,
		)
		if err != nil {
			return nil, err
		}
		users = append(users, user)
	}

	return users, nil
}