<?php
require_once 'config.php';
checkLogin();

$user = getCurrentUser();
$username = $user['username'];
$docDir = getUserDocDir($username);

// 搜索关键词
$search = trim($_GET['q'] ?? '');

// 解析 Markdown 文件的 YAML front matter
function parseMarkdownWithMeta($filePath) {
    $content = file_get_contents($filePath);
    $meta = [
        'title' => basename($filePath),
        'author' => '',
        'date' => '',
        'platform' => '',
        'url' => '',
        'summary' => ''
    ];
    
    // 解析 YAML front matter
    if (preg_match('/^---\s*\n(.*?)\n---\s*\n(.*)$/s', $content, $matches)) {
        $yaml = $matches[1];
        $body = $matches[2];
        
        // 解析 YAML 字段
        if (preg_match('/^title:\s*["\']?(.+?)["\']?\s*$/m', $yaml, $m)) {
            $meta['title'] = trim($m[1], '"\'');
        }
        if (preg_match('/^author:\s*(.+?)\s*$/m', $yaml, $m)) {
            $meta['author'] = trim($m[1]);
        }
        if (preg_match('/^date:\s*(.+?)\s*$/m', $yaml, $m)) {
            $meta['date'] = trim($m[1]);
        }
        if (preg_match('/^platform:\s*(.+?)\s*$/m', $yaml, $m)) {
            $meta['platform'] = trim($m[1]);
        }
        if (preg_match('/^url:\s*(.+?)\s*$/m', $yaml, $m)) {
            $meta['url'] = trim($m[1]);
        }
        
        // 提取正文概述（前两行非空内容）
        $lines = preg_split('/\r?\n/', trim($body));
        $summaryLines = [];
        foreach ($lines as $line) {
            $line = trim($line);
            if (empty($line) || strpos($line, '##') === 0) continue;
            $summaryLines[] = $line;
            if (count($summaryLines) >= 2) break;
        }
        $meta['summary'] = implode(' ', $summaryLines);
    } else {
        // 没有 front matter，从正文提取
        $lines = preg_split('/\r?\n/', trim($content));
        $summaryLines = [];
        foreach ($lines as $line) {
            $line = trim($line);
            if (empty($line) || strpos($line, '#') === 0) continue;
            $summaryLines[] = $line;
            if (count($summaryLines) >= 2) break;
        }
        $meta['summary'] = implode(' ', $summaryLines);
    }
    
    return $meta;
}

// 递归获取文档列表
$documents = [];

function scanDirectory($dir, $baseDir, $search) {
    $docs = [];
    if (!is_dir($dir)) return $docs;
    
    $items = scandir($dir);
    foreach ($items as $item) {
        if ($item === '.' || $item === '..') continue;
        
        $fullPath = $dir . '/' . $item;
        $relativePath = str_replace($baseDir . '/', '', $fullPath);
        
        if (is_dir($fullPath)) {
            $docs = array_merge($docs, scanDirectory($fullPath, $baseDir, $search));
        } elseif (is_file($fullPath)) {
            $ext = strtolower(pathinfo($item, PATHINFO_EXTENSION));
            if (!in_array($ext, ['md', 'txt', 'markdown'])) continue;
            
            $content = file_get_contents($fullPath);
            
            // 搜索过滤
            if ($search) {
                $searchLower = mb_strtolower($search);
                $contentLower = mb_strtolower($content);
                if (strpos($contentLower, $searchLower) === false) {
                    continue;
                }
            }
            
            // 解析元数据
            $meta = parseMarkdownWithMeta($fullPath);
            
            $docs[] = [
                'name' => $item,
                'path' => $relativePath,
                'folder' => dirname($relativePath) === '.' ? '' : dirname($relativePath),
                'size' => filesize($fullPath),
                'mtime' => filemtime($fullPath),
                'title' => $meta['title'],
                'author' => $meta['author'],
                'date' => $meta['date'],
                'platform' => $meta['platform'],
                'summary' => $meta['summary']
            ];
        }
    }
    return $docs;
}

$documents = scanDirectory($docDir, $docDir, $search);

// 按日期排序（新文件在前）
usort($documents, function($a, $b) {
    // 优先按日期排序
    if ($a['date'] && $b['date']) {
        return strcmp($b['date'], $a['date']);
    }
    // 其次按修改时间
    return $b['mtime'] - $a['mtime'];
});

// 平台图标映射
function getPlatformIcon($platform) {
    $icons = [
        'bilibili' => '📺',
        'youtube' => '▶️',
        'zhihu' => '💡',
        'wechat' => '💬',
    ];
    return $icons[$platform] ?? '📄';
}
?>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device=device-width, initial-scale=1.0">
    <title>知识库 - <?php echo htmlspecialchars($username); ?></title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
    <div class="dashboard">
        <header class="header">
            <h1>📚 我的知识库</h1>
            <div class="user-info">
                <span><?php echo htmlspecialchars($username); ?></span>
                <a href="logout.php" class="btn-logout">退出</a>
            </div>
        </header>
        
        <div class="search-bar">
            <form method="GET" action="">
                <input type="text" name="q" placeholder="搜索文档..." 
                       value="<?php echo htmlspecialchars($search); ?>">
                <button type="submit">搜索</button>
                <?php if ($search): ?>
                    <a href="dashboard.php" class="btn-clear">清除</a>
                <?php endif; ?>
            </form>
        </div>
        
        <div class="stats">
            共 <?php echo count($documents); ?> 个文档
            <?php if ($search): ?>
                <span class="search-hint">（搜索: "<?php echo htmlspecialchars($search); ?>"）</span>
            <?php endif; ?>
        </div>
        
        <div class="document-list">
            <?php if (empty($documents)): ?>
                <div class="empty">
                    <?php if ($search): ?>
                        没有找到匹配的文档
                    <?php else: ?>
                        暂无文档
                    <?php endif; ?>
                </div>
            <?php else: ?>
                <?php foreach ($documents as $doc): ?>
                    <a href="view.php?file=<?php echo urlencode($doc['path']); ?><?php echo $search ? '&q=' . urlencode($search) : ''; ?>" 
                       class="document-card">
                        <div class="doc-icon"><?php echo getPlatformIcon($doc['platform']); ?></div>
                        <div class="doc-info">
                            <div class="doc-title"><?php echo htmlspecialchars($doc['title']); ?></div>
                            <div class="doc-meta">
                                <?php if ($doc['author']): ?>
                                    <span class="meta-author">👤 <?php echo htmlspecialchars($doc['author']); ?></span>
                                <?php endif; ?>
                                <?php if ($doc['date']): ?>
                                    <span class="meta-date">📅 <?php echo htmlspecialchars($doc['date']); ?></span>
                                <?php endif; ?>
                                <?php if ($doc['platform']): ?>
                                    <span class="meta-platform">🏷️ <?php echo htmlspecialchars($doc['platform']); ?></span>
                                <?php endif; ?>
                            </div>
                            <?php if ($doc['summary']): ?>
                                <div class="doc-summary"><?php echo htmlspecialchars(mb_substr($doc['summary'], 0, 150)); ?><?php echo mb_strlen($doc['summary']) > 150 ? '...' : ''; ?></div>
                            <?php endif; ?>
                        </div>
                    </a>
                <?php endforeach; ?>
            <?php endif; ?>
        </div>
    </div>
</body>
</html>