ff14-mitigator/api/cache.php

<?php
declare(strict_types=1);

const CACHED_LOG_DIR = __DIR__ . '/../cached_logs';
const CACHED_LOG_VERSION = 'v8';

function cache_language(string $language): string {
    $language = strtolower(trim($language));
    return in_array($language, ['en', 'de', 'fr', 'jp'], true) ? $language : 'en';
}

function cache_report_code(string $reportCode): string {
    return preg_replace('/[^a-zA-Z0-9]/', '', $reportCode);
}

function cache_key_part(string|int|float|null $value): string {
    $value = (string)($value ?? '');
    $value = preg_replace('/[^a-zA-Z0-9._-]/', '_', $value);
    return trim($value, '_') ?: 'all';
}

function cached_log_path(string $kind, string $reportCode, string $language, array $parts = []): string {
    $reportCode = cache_report_code($reportCode);
    $language   = cache_language($language);
    $kind       = cache_key_part($kind);
    $safeParts  = array_map('cache_key_part', $parts);
    $suffix     = $safeParts ? '_' . implode('_', $safeParts) : '';

    return CACHED_LOG_DIR . '/' . CACHED_LOG_VERSION . '/' . $reportCode . '/' . $language . '/' . $kind . $suffix . '.json';
}

function read_cached_log(string $kind, string $reportCode, string $language, array $parts = []): ?string {
    $path = cached_log_path($kind, $reportCode, $language, $parts);
    if (!is_file($path)) return null;

    $body = file_get_contents($path);
    if ($body === false || trim($body) === '') return null;
    return $body;
}

function write_cached_log(string $kind, string $reportCode, string $language, array $parts, string $body): void {
    $decoded = json_decode($body, true);
    if (!is_array($decoded) || isset($decoded['error'], $decoded['errors'], $decoded['reauth'])) return;

    $path = cached_log_path($kind, $reportCode, $language, $parts);
    $dir  = dirname($path);
    if (!is_dir($dir) && !mkdir($dir, 0775, true) && !is_dir($dir)) return;

    $tmp = $path . '.' . bin2hex(random_bytes(4)) . '.tmp';
    if (file_put_contents($tmp, $body, LOCK_EX) === false) return;
    rename($tmp, $path);
}