<?php
// api/messages.php
define('CYBERCHAT_API', true);
require_once __DIR__ . '/../bootstrap.php';
sendCorsHeaders();

header('Content-Type: application/json');
header('Cache-Control: no-store');

// Run archiving silently
try { archiveYesterdayIfNeeded(); } catch (Throwable $e) { /* silent */ }

$action = $_POST['action'] ?? $_GET['action'] ?? '';

switch ($action) {
    case 'send':
        handleSend();
        break;
    case 'send_voice':
        handleSendVoice();
        break;
    case 'poll':
        handlePoll();
        break;
    case 'history':
        handleHistory();
        break;
    default:
        jsonResponse(['error' => 'Unknown action'], 400);
}

function messagePayload(array $row): array {
    return [
        'id' => (int)$row['id'],
        'username' => $row['username'],
        'color' => $row['color'],
        'message' => $row['message'],
        'message_type' => $row['message_type'] ?? 'text',
        'voice_url' => !empty($row['voice_file']) ? voicePublicPath($row['voice_file']) : null,
        'voice_mime' => $row['voice_mime'] ?? null,
        'voice_duration' => isset($row['voice_duration']) ? (float)$row['voice_duration'] : null,
        'created_at' => (int)$row['created_at'],
        'day_key' => $row['day_key'] ?? dayKey(),
    ];
}

function handleSend(): never {
    $session = authRequired();
    $db = getDB();

    $message = trim($_POST['message'] ?? '');
    $maxLen = getConfigVal('chat.max_message_length', 500);

    if (!$message) jsonResponse(['error' => 'Empty message'], 400);
    if (strlen($message) > $maxLen) {
        jsonResponse(['error' => "Message too long (max {$maxLen} chars)"], 400);
    }

    $dayKey = dayKey();

    $stmt = $db->prepare("
        INSERT INTO messages (user_id, username, color, message, created_at, day_key)
        VALUES (?, ?, ?, ?, ?, ?)
    ");
    $stmt->execute([
        $session['uid'],
        $session['username'],
        $session['color'],
        $message,
        time(),
        $dayKey
    ]);

    $id = $db->lastInsertId();

    jsonResponse(['success' => true, 'message' => messagePayload([
        'id' => $id, 'username' => $session['username'], 'color' => $session['color'],
        'message' => $message, 'message_type' => 'text', 'created_at' => time(), 'day_key' => $dayKey,
    ])]);
}

function handleSendVoice(): never {
    $session = authRequired();
    if (!getConfigVal('voice.enabled', true)) {
        jsonResponse(['error' => 'Voice clips are disabled'], 403);
    }
    if (empty($_FILES['voice']) || !is_array($_FILES['voice'])) {
        jsonResponse(['error' => 'No voice clip uploaded'], 400);
    }

    $file = $_FILES['voice'];
    if (($file['error'] ?? UPLOAD_ERR_NO_FILE) !== UPLOAD_ERR_OK) {
        jsonResponse(['error' => 'Voice upload failed'], 400);
    }

    $maxBytes = (int)getConfigVal('voice.max_upload_bytes', 12582912);
    if (($file['size'] ?? 0) < 1 || $file['size'] > $maxBytes) {
        jsonResponse(['error' => 'Voice clip exceeds the upload limit'], 400);
    }

    $duration = (float)($_POST['duration'] ?? 0);
    $maxSeconds = max(1, (int)getConfigVal('voice.max_duration_seconds', 60));
    if ($duration <= 0 || $duration > $maxSeconds + 1) {
        jsonResponse(['error' => "Voice clip must be {$maxSeconds} seconds or less"], 400);
    }

    $mime = class_exists('finfo')
        ? (string)(new finfo(FILEINFO_MIME_TYPE))->file($file['tmp_name'])
        : '';
    $header = (string)file_get_contents($file['tmp_name'], false, null, 0, 12);
    if (str_starts_with($header, "\x1A\x45\xDF\xA3")) {
        $mime = 'audio/webm';
    } elseif (str_starts_with($header, 'RIFF') && substr($header, 8, 4) === 'WAVE') {
        $mime = 'audio/wav';
    }
    $allowed = [
        'audio/webm' => 'webm',
        'video/webm' => 'webm',
        'audio/wav' => 'wav',
        'audio/x-wav' => 'wav',
        'audio/wave' => 'wav',
    ];
    if (!isset($allowed[$mime])) {
        jsonResponse(['error' => 'Voice clips must be WAV or WebM'], 400);
    }

    $dir = voiceUploadDir();
    if (!is_dir($dir) && !mkdir($dir, 0755, true)) {
        jsonResponse(['error' => 'Voice storage is unavailable'], 500);
    }
    $filename = bin2hex(random_bytes(20)) . '.' . $allowed[$mime];
    if (!move_uploaded_file($file['tmp_name'], $dir . '/' . $filename)) {
        jsonResponse(['error' => 'Could not store voice clip'], 500);
    }

    $db = getDB();
    $created = time();
    $dayKey = dayKey();
    try {
        $stmt = $db->prepare("
            INSERT INTO messages
                (user_id, username, color, message, message_type, voice_file, voice_mime, voice_duration, created_at, day_key)
            VALUES (?, ?, ?, ?, 'voice', ?, ?, ?, ?, ?)
        ");
        $stmt->execute([
            $session['uid'], $session['username'], $session['color'], '[Voice clip]',
            $filename, $mime === 'video/webm' ? 'audio/webm' : $mime, $duration, $created, $dayKey
        ]);
    } catch (Throwable $e) {
        deleteVoiceFile($filename);
        throw $e;
    }

    jsonResponse(['success' => true, 'message' => messagePayload([
        'id' => $db->lastInsertId(), 'username' => $session['username'], 'color' => $session['color'],
        'message' => '[Voice clip]', 'message_type' => 'voice', 'voice_file' => $filename,
        'voice_mime' => $mime === 'video/webm' ? 'audio/webm' : $mime,
        'voice_duration' => $duration, 'created_at' => $created, 'day_key' => $dayKey,
    ])]);
}

function handlePoll(): never {
    $session = authRequired();
    $db = getDB();

    $since = (int)($_GET['since'] ?? 0);
    $dayKey = dayKey();
    $limit = getConfigVal('chat.messages_per_page', 100);

    if ($since === 0) {
        // Initial load — get last N messages for today
        $stmt = $db->prepare("
            SELECT id, username, color, message, message_type, voice_file, voice_mime, voice_duration, created_at, day_key
            FROM messages
            WHERE day_key = ?
            ORDER BY created_at DESC, id DESC
            LIMIT ?
        ");
        $stmt->execute([$dayKey, $limit]);
        $rows = array_reverse($stmt->fetchAll(PDO::FETCH_ASSOC));
    } else {
        // Poll for new messages since last id
        $stmt = $db->prepare("
            SELECT id, username, color, message, message_type, voice_file, voice_mime, voice_duration, created_at, day_key
            FROM messages
            WHERE day_key = ? AND id > ?
            ORDER BY created_at ASC, id ASC
            LIMIT ?
        ");
        $stmt->execute([$dayKey, $since, $limit]);
        $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
    }

    // Cast types
    $messages = array_map('messagePayload', $rows);

    // Get online user count (active in last 5 minutes)
    $cutoff5min = time() - 300;
    $onlineStmt = $db->prepare("SELECT COUNT(*) FROM sessions WHERE last_active > ?");
    $onlineStmt->execute([$cutoff5min]);
    $onlineCount = (int)$onlineStmt->fetchColumn();

    jsonResponse([
        'messages' => $messages,
        'online' => $onlineCount,
        'day_key' => $dayKey,
        'server_time' => time(),
    ]);
}

function handleHistory(): never {
    // Return list of archived days
    $archiveDir = ROOT_DIR . '/' . getConfigVal('archive.archive_dir', 'archive');
    $days = [];

    if (is_dir($archiveDir)) {
        $years = glob($archiveDir . '/*', GLOB_ONLYDIR);
        foreach ($years as $yearDir) {
            $year = basename($yearDir);
            $months = glob($yearDir . '/*', GLOB_ONLYDIR);
            foreach ($months as $monthDir) {
                $month = basename($monthDir);
                $files = glob($monthDir . '/*.sqlite');
                foreach ($files as $file) {
                    $day = basename($file, '.sqlite');
                    $days[] = "$year-$month-$day";
                }
            }
        }
    }

    rsort($days);
    jsonResponse(['days' => $days]);
}