package database

import (
	"database/sql"
	"fmt"
	_ "github.com/lib/pq"
	"log"
)

func GetUsers(db *sql.DB) ([]string, error) {
	query := `SELECT username FROM accounts;`

	rows, err := db.Query(query)
	if err != nil {
		log.Fatal(err)
	}

	var users []string
	for rows.Next() {
		var user string
		if err := rows.Scan(&user); err != nil {
			return nil, err
		}
		users = append(users, user)
	}
	return users, err
}

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, fmt.Errorf("error checking username exists: %v", err)
	}

	return count > 0, err
}

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 "", fmt.Errorf("error inserting user: %v", err)
	}
	return userId, err
}

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 {
		fmt.Printf("error getting password: %v\n", err)
		return "", fmt.Errorf("error getting password: %v", err)
	}

	return passwordHash, err
}

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

	var dbUsername string
	err := db.QueryRow(query, username).Scan(&dbUsername)
	if err != nil {
		fmt.Printf("Error getting password: %v\n", err)
		return "", fmt.Errorf("error getting user id: %v", err)
	}
	return dbUsername, err
}