<?php
declare(strict_types=1);

if (defined('OG_USER_AVATAR_HELPER_LOADED')) {
    return;
}

define('OG_USER_AVATAR_HELPER_LOADED', true);

function og_users_has_column(PDO $pdo, string $columnName): bool
{
    try {
        $database = (string)$pdo->query('SELECT DATABASE()')->fetchColumn();
        if ($database === '') {
            return false;
        }

        $stmt = $pdo->prepare(
            'SELECT COUNT(*) FROM information_schema.columns WHERE table_schema = :schema AND table_name = :table AND column_name = :column'
        );
        $stmt->execute([
            ':schema' => $database,
            ':table' => 'users',
            ':column' => $columnName,
        ]);

        return (int)$stmt->fetchColumn() > 0;
    } catch (Throwable $e) {
        return false;
    }
}

function og_ensure_users_avatar_column(PDO $pdo): bool
{
    if (og_users_has_column($pdo, 'profile_avatar_file')) {
        return true;
    }

    try {
        $pdo->exec('ALTER TABLE users ADD COLUMN profile_avatar_file VARCHAR(255) NULL AFTER phone_number');
    } catch (Throwable $e) {
        return og_users_has_column($pdo, 'profile_avatar_file');
    }

    return og_users_has_column($pdo, 'profile_avatar_file');
}

function og_get_user_avatar_file(PDO $pdo, int $userId): ?string
{
    if (!og_users_has_column($pdo, 'profile_avatar_file')) {
        return null;
    }

    try {
        $stmt = $pdo->prepare('SELECT profile_avatar_file FROM users WHERE id = ? LIMIT 1');
        $stmt->execute([$userId]);
        $value = $stmt->fetchColumn();
        if (!is_string($value)) {
            return null;
        }

        $file = trim($value);
        if ($file === '') {
            return null;
        }

        if (!preg_match('/^[A-Za-z0-9._-]{1,255}$/', $file)) {
            return null;
        }

        return $file;
    } catch (Throwable $e) {
        return null;
    }
}

function og_avatar_file_to_url(?string $avatarFile): ?string
{
    $file = trim((string)$avatarFile);
    if ($file === '') {
        return null;
    }

    if (!preg_match('/^[A-Za-z0-9._-]{1,255}$/', $file)) {
        return null;
    }

    return '/account/avatar.php?f=' . rawurlencode($file);
}

function og_avatar_initial(?string $username): string
{
    $name = trim((string)$username);
    if ($name === '') {
        return '?';
    }

    if (function_exists('mb_substr') && function_exists('mb_strtoupper')) {
        return mb_strtoupper(mb_substr($name, 0, 1, 'UTF-8'), 'UTF-8');
    }

    return strtoupper(substr($name, 0, 1));
}