<?php
declare(strict_types=1);

if (PHP_SAPI !== 'cli') {
    http_response_code(404);
    exit;
}

require_once __DIR__ . '/app.php';
require_once __DIR__ . '/zefixAPI.php';
require_once __DIR__ . '/emailSender.php';

$maxExecutionTime = app_env_int('TASK_EXECUTOR_MAX_SECONDS', 120, 30, 900);
$minimumTaskAge = app_env_int('TASK_MIN_AGE_SECONDS', 10, 0, 300);
$latestEndTime = time() + $maxExecutionTime;
$smtpPassword = app_env('smtppassword');

app_migrate_legacy_tasks();
$downloadRetention = app_env_int('DOWNLOAD_RETENTION_HOURS', 48, 1, 720) * 3600;
$staleTaskRetention = app_env_int('STALE_TASK_RETENTION_HOURS', 168, 24, 2160) * 3600;
app_cleanup_directory(app_download_dir(), $downloadRetention, 'csv');
app_cleanup_directory(app_task_dir(), $staleTaskRetention, 'json');
app_cleanup_directory(__DIR__ . DIRECTORY_SEPARATOR . 'download', $downloadRetention, 'csv');

$executorLock = fopen(app_private_dir() . DIRECTORY_SEPARATOR . 'executor.lock', 'c+');
if ($executorLock === false || !flock($executorLock, LOCK_EX | LOCK_NB)) {
    fwrite(STDOUT, "Another executor is already running.\n");
    exit(0);
}

/**
 * @return int|false|null Next offset, false when complete, null on a temporary error.
 */
function doRequest(array $data, string $filename, string $username, string $password): int|false|null
{
    $response = sendAPICompanySearchRequest($username, $password, $data);
    if (!is_string($response) || $response === '') {
        return null;
    }

    $responseObject = json_decode($response, true);
    if (!is_array($responseObject) || array_key_exists('error', $responseObject) || !is_array($responseObject['list'] ?? null)) {
        error_log('ZEFIX search returned an invalid or error response.');
        return null;
    }

    $companyData = [];
    foreach ($responseObject['list'] as $company) {
        if (!is_array($company) || !isset($company['uid'])) {
            continue;
        }

        $detailsResponse = sendAPICompanyInfoRequest($username, $password, (string)$company['uid']);
        $details = is_string($detailsResponse) ? json_decode($detailsResponse, true) : null;
        $companyFullData = is_array($details) && is_array($details[0] ?? null) ? $details[0] : null;
        if ($companyFullData === null) {
            continue;
        }

        $companyData[] = [
            $companyFullData['name'] ?? '',
            $companyFullData['address']['careOf'] ?? '',
            $companyFullData['address']['street'] ?? '',
            $companyFullData['address']['houseNumber'] ?? '',
            $companyFullData['address']['swissZipCode'] ?? '',
            $companyFullData['address']['city'] ?? '',
            $companyFullData['uid'] ?? '',
            $companyFullData['legalSeat'] ?? '',
            $companyFullData['legalForm']['name']['de'] ?? '',
            $companyFullData['status'] ?? '',
            $companyFullData['sogcDate'] ?? '',
            $companyFullData['deletionDate'] ?? '',
        ];
    }

    $isNewFile = !is_file($filename);
    $file = fopen($filename, $isNewFile ? 'x' : 'a');
    if ($file === false) {
        error_log('Export file could not be opened.');
        return null;
    }

    try {
        if ($isNewFile) {
            fputcsv($file, ['name', 'careOf', 'street', 'houseNumber', 'swissZipCode', 'city', 'uid', 'legalSeat', 'legalForm', 'status', 'sogcDate', 'deletionDate'], ',', '"', '\\');
            @chmod($filename, 0600);
        }
        foreach ($companyData as $row) {
            fputcsv($file, $row, ',', '"', '\\');
        }
    } finally {
        fclose($file);
    }

    return ($responseObject['hasMoreResults'] ?? false)
        ? (int)($responseObject['maxOffset'] ?? 0)
        : false;
}

function saveTask(string $filename, array $task): bool
{
    $temporary = $filename . '.tmp';
    $written = file_put_contents($temporary, json_encode($task, JSON_THROW_ON_ERROR), LOCK_EX);
    if ($written === false || !rename($temporary, $filename)) {
        @unlink($temporary);
        return false;
    }
    @chmod($filename, 0600);
    return true;
}

try {
    while ($latestEndTime - time() > 30) {
        $taskFiles = glob(app_task_dir() . DIRECTORY_SEPARATOR . '*.json') ?: [];
        sort($taskFiles, SORT_STRING);

        if ($taskFiles === []) {
            fwrite(STDOUT, "Nothing to do.\n");
            break;
        }

        $taskFilename = $taskFiles[0];
        $modified = filemtime($taskFilename);
        if ($modified !== false && $modified + $minimumTaskAge > time()) {
            sleep(min(5, max(1, ($modified + $minimumTaskAge) - time())));
            continue;
        }

        $task = json_decode((string)file_get_contents($taskFilename), true);
        if (!is_array($task) || !is_array($task['requests'] ?? null) || !filter_var($task['email'] ?? '', FILTER_VALIDATE_EMAIL)) {
            error_log('Invalid task quarantined: ' . basename($taskFilename));
            @rename($taskFilename, $taskFilename . '.invalid');
            continue;
        }

        if (!preg_match('/^[a-f0-9]{32}$/', (string)($task['downloadToken'] ?? ''))) {
            $task['downloadToken'] = bin2hex(random_bytes(16));

            // Preserve partially generated exports from the previous public-download layout.
            $legacyCsv = __DIR__ . DIRECTORY_SEPARATOR . 'download' . DIRECTORY_SEPARATOR . pathinfo($taskFilename, PATHINFO_FILENAME) . '.csv';
            if (is_file($legacyCsv)) {
                @rename($legacyCsv, app_download_path($task['downloadToken']));
            }
            if (!saveTask($taskFilename, $task)) {
                error_log('Could not migrate legacy task metadata.');
                break;
            }
        }

        $csvFile = app_download_path((string)$task['downloadToken']);
        if ($task['requests'] !== []) {
            $nextOffset = doRequest($task['requests'][0], $csvFile, (string)$username, (string)$password);
            if ($nextOffset === null) {
                fwrite(STDOUT, "Temporary API error; task retained for retry.\n");
                break;
            }

            if ($nextOffset !== false) {
                $task['requests'][0]['offset'] = $nextOffset;
            } else {
                array_shift($task['requests']);
            }

            if (!saveTask($taskFilename, $task)) {
                error_log('Could not save task progress.');
                break;
            }
            continue;
        }

        if (!is_file($csvFile)) {
            $emptyFile = fopen($csvFile, 'x');
            if ($emptyFile !== false) {
                fputcsv($emptyFile, ['name', 'careOf', 'street', 'houseNumber', 'swissZipCode', 'city', 'uid', 'legalSeat', 'legalForm', 'status', 'sogcDate', 'deletionDate'], ',', '"', '\\');
                fclose($emptyFile);
                @chmod($csvFile, 0600);
            }
        }

        if (sendEmail((string)$task['email'], (string)$task['downloadToken'], $smtpPassword)) {
            unlink($taskFilename);
            fwrite(STDOUT, 'Completed ' . basename($taskFilename) . ".\n");
        } else {
            fwrite(STDOUT, "Email delivery failed; task retained for retry.\n");
            break;
        }
    }
} finally {
    flock($executorLock, LOCK_UN);
    fclose($executorLock);
}