package database

import (
	"database/sql"
	"errors"
	"github.com/google/uuid"
	_ "github.com/lib/pq"
	"relay-server/utils"
)

func CheckUserExists(db *sql.DB, username string) (bool, error) {
	query := `SELECT COUNT(1) FROM accounts WHERE username = $1`

	var count int
	err := db.QueryRow(query, username).Scan(&count)
	if err != nil {
		return false, utils.NewError(utils.ErrInternal, "Failed to check user existence", err)
	}

	return count > 0, nil
}

func InsertUser(db *sql.DB, username string, passwordHash string) (string, error) {
	query := `
        INSERT INTO Accounts (username, password_hash)
        VALUES ($1, $2)
        RETURNING user_id;
    `

	var userID string
	err := db.QueryRow(query, username, passwordHash).Scan(&userID)
	if err != nil {
		return "", utils.NewError(utils.ErrInternal, "Failed to create user", err)
	}

	return userID, nil
}

func GetPasswordHash(db *sql.DB, username string) (string, error) {
	query := `
        SELECT password_hash FROM Accounts 
        WHERE LOWER(username) = LOWER($1);
    `

	var passwordHash string
	err := db.QueryRow(query, username).Scan(&passwordHash)
	if err != nil {
		if errors.Is(err, sql.ErrNoRows) {
			return "", utils.NewError(utils.ErrNotFound, "User not found", nil)
		}
		return "", utils.NewError(utils.ErrInternal, "Failed to get user credentials", err)
	}

	return passwordHash, nil
}

func GetUserID(db *sql.DB, username string) (uuid.UUID, error) {
	query := `
        SELECT user_id FROM Accounts
        WHERE LOWER(username) = LOWER($1);
    `

	var userID uuid.UUID
	err := db.QueryRow(query, username).Scan(&userID)
	if err != nil {
		if errors.Is(err, sql.ErrNoRows) {
			return uuid.Nil, utils.NewError(utils.ErrNotFound, "User not found", nil)
		}
		return uuid.Nil, utils.NewError(utils.ErrInternal, "Failed to get user ID", err)
	}
	return userID, nil
}