#!/usr/bin/env php
<?php
/**
 * 一键恢复 uploads 图片（从 compress-uploads 生成的快照）
 *
 * 用法:
 *   php deploy/restore-uploads.php --list
 *   php deploy/restore-uploads.php --restore=latest
 *   php deploy/restore-uploads.php --restore=20260923_235800
 *   php deploy/restore-uploads.php --restore=latest --dry-run
 */

declare(strict_types=1);

set_time_limit(0);

const BACKUP_DIR_NAME = '.compress_backup';
const SNAPSHOTS_DIR = '.compress_backup/snapshots';

$options = getopt('', ['list', 'restore:', 'dry-run', 'path:', 'help']);

if (isset($options['help']) || (!isset($options['list']) && !isset($options['restore']))) {
    echo <<<HELP
一键恢复 uploads 图片

选项:
  --list                  列出所有可用快照
  --restore=ID            恢复快照（ID 或 latest）
  --dry-run               仅预览，不写入
  --path=DIR              uploads 目录
  --help                  显示帮助

示例:
  php deploy/restore-uploads.php --list
  php deploy/restore-uploads.php --restore=latest
  bash deploy/restore-uploads.sh --latest

HELP;
    exit(isset($options['help']) ? 0 : 1);
}

$dryRun = isset($options['dry-run']);
$projectRoot = dirname(__DIR__);
$uploadsDir = isset($options['path'])
    ? rtrim($options['path'], DIRECTORY_SEPARATOR)
    : $projectRoot . DIRECTORY_SEPARATOR . 'public' . DIRECTORY_SEPARATOR . 'uploads';

$snapshotsRoot = $uploadsDir . DIRECTORY_SEPARATOR . SNAPSHOTS_DIR;

if (!is_dir($uploadsDir)) {
    fwrite(STDERR, "ERROR: uploads 目录不存在: {$uploadsDir}\n");
    exit(1);
}

if (isset($options['list'])) {
    listSnapshots($snapshotsRoot);
    exit(0);
}

$restoreId = $options['restore'];
$snapshotDir = resolveSnapshotDir($snapshotsRoot, $restoreId);

if ($snapshotDir === null) {
    fwrite(STDERR, "ERROR: 找不到快照: {$restoreId}\n");
    fwrite(STDERR, "可用快照:\n");
    listSnapshots($snapshotsRoot);
    exit(1);
}

echo "恢复快照: " . basename($snapshotDir) . "\n";
echo "目标目录: {$uploadsDir}\n";
echo ($dryRun ? "[dry-run] 仅预览\n" : '') . "\n";

$metaFile = $snapshotDir . DIRECTORY_SEPARATOR . '.snapshot_meta.json';
if (file_exists($metaFile)) {
    $meta = json_decode(file_get_contents($metaFile), true);
    if ($meta) {
        echo '快照时间: ' . ($meta['created_at'] ?? '-') . "\n";
        echo '图片数量: ' . ($meta['image_count'] ?? '-') . "\n";
        echo '快照大小: ' . formatBytes((int) ($meta['total_bytes'] ?? 0)) . "\n\n";
    }
}

$restored = 0;
$bytes = 0;
$errors = 0;

$iterator = new RecursiveIteratorIterator(
    new RecursiveDirectoryIterator($snapshotDir, FilesystemIterator::SKIP_DOTS)
);

foreach ($iterator as $fileInfo) {
    /** @var SplFileInfo $fileInfo */
    if (!$fileInfo->isFile()) {
        continue;
    }

    $src = $fileInfo->getPathname();
    $relative = ltrim(str_replace($snapshotDir, '', $src), DIRECTORY_SEPARATOR);

    if ($relative === '.snapshot_meta.json') {
        continue;
    }

    $dst = $uploadsDir . DIRECTORY_SEPARATOR . $relative;

    if ($dryRun) {
        echo "[RESTORE] {$relative}\n";
        $restored++;
        continue;
    }

    $dstDir = dirname($dst);
    if (!is_dir($dstDir) && !mkdir($dstDir, 0755, true) && !is_dir($dstDir)) {
        echo "[ERR] 无法创建目录: {$dstDir}\n";
        $errors++;
        continue;
    }

    if (!copy($src, $dst)) {
        echo "[ERR] 恢复失败: {$relative}\n";
        $errors++;
        continue;
    }

    @chmod($dst, 0644);
    $restored++;
    $bytes += filesize($src) ?: 0;

    if ($restored % 200 === 0) {
        echo "--- 已恢复 {$restored} 文件 ---\n";
    }
}

echo "\n========== 完成 ==========\n";
echo "恢复: {$restored} 个文件";
if (!$dryRun) {
    echo ', ' . formatBytes($bytes);
}
echo "\n";
echo "失败: {$errors}\n";

exit($errors > 0 ? 1 : 0);

function listSnapshots(string $snapshotsRoot): void
{
    if (!is_dir($snapshotsRoot)) {
        echo "暂无快照（目录不存在: {$snapshotsRoot}）\n";
        echo "请先执行: bash deploy/compress-uploads.sh --safe\n";
        return;
    }

    $dirs = glob($snapshotsRoot . DIRECTORY_SEPARATOR . '*', GLOB_ONLYDIR);
    if (!$dirs) {
        echo "暂无快照\n";
        return;
    }

    rsort($dirs);
    echo "可用快照:\n";
    foreach ($dirs as $dir) {
        $id = basename($dir);
        $metaFile = $dir . DIRECTORY_SEPARATOR . '.snapshot_meta.json';
        $extra = '';
        if (file_exists($metaFile)) {
            $meta = json_decode(file_get_contents($metaFile), true);
            if ($meta) {
                $extra = ' | ' . ($meta['created_at'] ?? '') . ' | '
                    . ($meta['image_count'] ?? '?') . ' 张 | '
                    . formatBytes((int) ($meta['total_bytes'] ?? 0));
            }
        }
        $marker = ($dir === $dirs[0]) ? ' <- latest' : '';
        echo "  {$id}{$extra}{$marker}\n";
    }
}

function resolveSnapshotDir(string $snapshotsRoot, string $id): ?string
{
    if ($id === 'latest') {
        if (!is_dir($snapshotsRoot)) {
            return null;
        }
        $dirs = glob($snapshotsRoot . DIRECTORY_SEPARATOR . '*', GLOB_ONLYDIR);
        if (!$dirs) {
            return null;
        }
        rsort($dirs);
        return $dirs[0];
    }

    $dir = $snapshotsRoot . DIRECTORY_SEPARATOR . $id;
    return is_dir($dir) ? $dir : null;
}

function formatBytes(int $bytes): string
{
    if ($bytes >= 1073741824) {
        return round($bytes / 1073741824, 2) . 'GB';
    }
    if ($bytes >= 1048576) {
        return round($bytes / 1048576, 2) . 'MB';
    }
    if ($bytes >= 1024) {
        return round($bytes / 1024, 1) . 'KB';
    }
    return $bytes . 'B';
}