package repository

import (
	"context"
	"errors"

	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgconn"
	"github.com/jackc/pgx/v5/pgxpool"

	"shop/internal/models"
)

type UserRepository struct {
	pool *pgxpool.Pool
}

func NewUserRepository(pool *pgxpool.Pool) *UserRepository {
	return &UserRepository{pool: pool}
}

func (r *UserRepository) Create(ctx context.Context, email, passwordHash, name string) (*models.User, error) {
	var u models.User
	err := r.pool.QueryRow(ctx, `
		INSERT INTO users (email, password_hash, name)
		VALUES ($1, $2, $3)
		RETURNING id, email, name, created_at`,
		email, passwordHash, name,
	).Scan(&u.ID, &u.Email, &u.Name, &u.CreatedAt)
	if err != nil {
		return nil, err
	}
	return &u, nil
}

func (r *UserRepository) ByID(ctx context.Context, id int) (*models.User, error) {
	var u models.User
	err := r.pool.QueryRow(ctx, `
		SELECT id, email, name, created_at FROM users WHERE id = $1`, id,
	).Scan(&u.ID, &u.Email, &u.Name, &u.CreatedAt)
	if errors.Is(err, pgx.ErrNoRows) {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	return &u, nil
}

func (r *UserRepository) ByEmailWithHash(ctx context.Context, email string) (*models.User, string, error) {
	var u models.User
	var hash string
	err := r.pool.QueryRow(ctx, `
		SELECT id, email, name, created_at, password_hash
		FROM users WHERE email = $1`, email,
	).Scan(&u.ID, &u.Email, &u.Name, &u.CreatedAt, &hash)
	if errors.Is(err, pgx.ErrNoRows) {
		return nil, "", nil
	}
	if err != nil {
		return nil, "", err
	}
	return &u, hash, nil
}

func (r *UserRepository) UpdateName(ctx context.Context, userID int, name string) error {
	_, err := r.pool.Exec(ctx, `UPDATE users SET name = $1 WHERE id = $2`, name, userID)
	return err
}

func (r *UserRepository) Count(ctx context.Context) (int, error) {
	var n int
	err := r.pool.QueryRow(ctx, `SELECT COUNT(*) FROM users`).Scan(&n)
	return n, err
}

func IsUniqueViolation(err error) bool {
	var pgErr *pgconn.PgError
	return errors.As(err, &pgErr) && pgErr.Code == "23505"
}