package db

import (
	"context"
	"fmt"
	"log"

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

// db connection info
// !MIGHT CHANGE
const (
	host     = "localhost"
	port     = 5432
	user     = "asdfuser"
	password = "asdfpassword"
	dbname   = "asdfdb"
)

var DbPool *pgxpool.Pool
var allowedUsernames map[string]bool

// initialize connection to db
func ConnectToDb() (*pgxpool.Pool, error) {
	// this server is intended to be ran on the same system as the db
	dbUrl := fmt.Sprintf("postgresql://%s:%s@%s:%d/%s", user, password, host, port, dbname)
	config, err := pgxpool.ParseConfig((dbUrl))
	if err != nil {
		return nil, fmt.Errorf("unable to parse data URL: %w", err)
	}

	pool, err := pgxpool.NewWithConfig(context.Background(), config)
	if err != nil {
		return nil, fmt.Errorf("unable to create connection pool: %w", err)
	}

	log.Println("Connected to DB :)")
	return pool, nil
}

// fetch existing usernames from db
func FetchUsernames() (map[string]bool, error) {
	usernames := make(map[string]bool)

	rows, err := DbPool.Query(context.Background(), "SELECT username FROM users")
	if err != nil {
		return nil, fmt.Errorf("error querying users: %w", err)
	}
	defer rows.Close()

	for rows.Next() {
		var username string
		if err := rows.Scan(&username); err != nil {
			return nil, fmt.Errorf("error scanning username: %w", err)
		}
		usernames[username] = true
	}

	log.Println("Fetched usernames:", usernames)
	return usernames, nil
}