<?php
declare(strict_types=1);

/**
 * Explicit migration runner. It never drops a database and does not run from
 * HTTP. Usage: php backend/scripts/run_migrations.php [--dry-run|--status].
 */
require_once dirname(__DIR__) . '/app/bootstrap.php';

use App\Core\Database;

$mode = in_array('--status', $argv, true) ? 'status' : (in_array('--dry-run', $argv, true) ? 'dry_run' : 'apply');
$dir = dirname(__DIR__) . '/migrations';
$files = glob($dir . '/*.sql') ?: [];
sort($files, SORT_STRING);
$pdo = Database::getConnection();
$pdo->exec("CREATE TABLE IF NOT EXISTS schema_migrations (filename VARCHAR(255) NOT NULL PRIMARY KEY, sha256 CHAR(64) NOT NULL, applied_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4");
$applied = Database::select('SELECT filename, sha256, applied_at FROM schema_migrations ORDER BY filename');
$known = array_column($applied, null, 'filename');

foreach ($files as $file) {
    $name = basename($file); $sha = hash_file('sha256', $file);
    if (isset($known[$name])) {
        if (!hash_equals((string)$known[$name]['sha256'], $sha)) { fwrite(STDERR, "REFUSE {$name}: applied migration checksum changed.\n"); exit(2); }
        echo "APPLIED  {$name}  {$known[$name]['applied_at']}\n"; continue;
    }
    if ($mode === 'status') { echo "PENDING  {$name}\n"; continue; }
    if ($mode === 'dry_run') { echo "WOULD APPLY  {$name}\n"; continue; }
    $sql = file_get_contents($file);
    if ($sql === false || trim($sql) === '') { fwrite(STDERR, "REFUSE {$name}: unreadable or empty.\n"); exit(2); }
    echo "APPLYING {$name}\n";
    try {
        // MySQL DDL may commit implicitly. The migration is recorded only after
        // its complete SQL succeeds; repair any partial DDL manually before retry.
        $pdo->exec($sql);
        Database::insert('INSERT INTO schema_migrations (filename, sha256) VALUES (?, ?)', [$name, $sha]);
        echo "APPLIED  {$name}\n";
    } catch (Throwable $e) {
        fwrite(STDERR, "FAILED {$name}: {$e->getMessage()}\n");
        exit(1);
    }
}