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

try { archiveYesterdayIfNeeded(); } catch (Throwable $e) { error_log($e->getMessage()); }
$action = $_POST['action'] ?? $_GET['action'] ?? '';

switch ($action) {
    case 'send': sendTextMessage();
    case 'send_voice': sendVoiceMessage();
    case 'recording': setRecordingStatus();
    case 'poll': pollMessages();
    case 'history': archiveDays();
    default: jsonResponse(['error' => 'Unknown action'], 400);
}

function messagePayload(array $row): array {
    return [
        'id' => (int)$row['id'],
        'group_id' => isset($row['group_id']) && $row['group_id'] !== null ? (int)$row['group_id'] : null,
        '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 requestedGroup(array $user): ?int {
    $groupId = normalizeGroupId($_POST['group_id'] ?? $_GET['group_id'] ?? null);
    if ($groupId !== null && !groupsAvailableForUser($user)) {
        $error = groupsEnabled()
            ? 'Private groups are not available on your tier'
            : 'Private groups are currently disabled';
        jsonResponse([
            'error' => $error,
            'groups_enabled' => false,
            'groups_platform_enabled' => groupsEnabled(),
        ], 403);
    }
    requireGroupAccess($user, $groupId);
    return $groupId;
}

function sendTextMessage(): never {
    $user = authRequired();
    $groupId = requestedGroup($user);
    $message = trim((string)($_POST['message'] ?? ''));
    $max = (int)getConfigVal('chat.max_message_length', 500);
    if ($message === '') jsonResponse(['error' => 'Empty message'], 400);
    if (strlen($message) > $max) jsonResponse(['error' => "Message too long (max $max chars)"], 400);
    $created = time();
    $db = getDB();
    $db->prepare("INSERT INTO messages (user_id,group_id,username,color,message,created_at,day_key)
        VALUES (?,?,?,?,?,?,?)")->execute([
            $user['id'], $groupId, $user['username'], $user['color'], $message, $created, dayKey(),
        ]);
    if ($groupId !== null) {
        $db->prepare("UPDATE chat_groups SET updated_at=? WHERE id=?")->execute([$created, $groupId]);
    }
    trackEvent('message_text', '/api/messages.php', (int)$user['id']);
    jsonResponse(['success' => true, 'message' => messagePayload([
        'id' => $db->lastInsertId(), 'group_id' => $groupId, 'username' => $user['username'],
        'color' => $user['color'], 'message' => $message, 'message_type' => 'text',
        'created_at' => $created, 'day_key' => dayKey(),
    ])]);
}

function sendVoiceMessage(): never {
    $user = authRequired();
    $groupId = requestedGroup($user);
    if (!getConfigVal('voice.enabled', true) || !featureValue($user, 'voice_messages', true)) {
        jsonResponse(['error' => 'Your plan does not include voice messages'], 403);
    }
    if (empty($_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);

    $dir = voiceUploadDir();
    ensureWritableDirectory($dir, 'Voice storage');
    $filename = bin2hex(random_bytes(20)) . '.' . $allowed[$mime];
    if (!move_uploaded_file($file['tmp_name'], $dir . '/' . $filename)) jsonResponse(['error' => 'Could not store voice clip'], 500);

    $created = time();
    $storedMime = $mime === 'video/webm' ? 'audio/webm' : $mime;
    $db = getDB();
    try {
        $db->prepare("INSERT INTO messages
            (user_id,group_id,username,color,message,message_type,voice_file,voice_mime,voice_duration,created_at,day_key)
            VALUES (?,?,?,?,?,'voice',?,?,?,?,?)")->execute([
                $user['id'], $groupId, $user['username'], $user['color'], '[Voice clip]',
                $filename, $storedMime, $duration, $created, dayKey(),
            ]);
        if ($groupId !== null) {
            $db->prepare("UPDATE chat_groups SET updated_at=? WHERE id=?")->execute([$created, $groupId]);
        }
    } catch (Throwable $e) {
        deleteVoiceFile($filename);
        throw $e;
    }
    getDB()->prepare("DELETE FROM recording_status WHERE group_key=? AND user_id=?")
        ->execute([groupKey($groupId), $user['id']]);
    trackEvent('message_voice', '/api/messages.php', (int)$user['id']);
    jsonResponse(['success' => true, 'message' => messagePayload([
        'id' => $db->lastInsertId(), 'group_id' => $groupId, 'username' => $user['username'],
        'color' => $user['color'], 'message' => '[Voice clip]', 'message_type' => 'voice',
        'voice_file' => $filename, 'voice_mime' => $storedMime, 'voice_duration' => $duration,
        'created_at' => $created, 'day_key' => dayKey(),
    ])]);
}

function setRecordingStatus(): never {
    $user = authRequired();
    if (!featureValue($user, 'recording_status', false)) {
        jsonResponse(['error' => 'Your plan does not include recording indicators'], 403);
    }
    $groupId = requestedGroup($user);
    $active = filter_var($_POST['active'] ?? false, FILTER_VALIDATE_BOOLEAN);
    $db = getDB();
    if ($active) {
        $db->prepare("INSERT INTO recording_status (group_key,user_id,expires_at) VALUES (?,?,?)
            ON CONFLICT(group_key,user_id) DO UPDATE SET expires_at=excluded.expires_at")
            ->execute([groupKey($groupId), $user['id'], time() + 10]);
    } else {
        $db->prepare("DELETE FROM recording_status WHERE group_key=? AND user_id=?")
            ->execute([groupKey($groupId), $user['id']]);
    }
    jsonResponse(['success' => true]);
}

function pollMessages(): never {
    $user = authRequired();
    $groupId = requestedGroup($user);
    $since = max(0, (int)($_GET['since'] ?? 0));
    $limit = max(1, min(250, (int)getConfigVal('chat.messages_per_page', 100)));
    $db = getDB();
    $whereGroup = $groupId === null ? 'group_id IS NULL' : 'group_id = ?';
    $params = $groupId === null ? [dayKey()] : [dayKey(), $groupId];
    if ($since === 0) {
        $stmt = $db->prepare("SELECT * FROM messages WHERE day_key=? AND $whereGroup ORDER BY id DESC LIMIT ?");
        $params[] = $limit;
        $stmt->execute($params);
        $rows = array_reverse($stmt->fetchAll());
    } else {
        $stmt = $db->prepare("SELECT * FROM messages WHERE day_key=? AND $whereGroup AND id>? ORDER BY id LIMIT ?");
        $params[] = $since;
        $params[] = $limit;
        $stmt->execute($params);
        $rows = $stmt->fetchAll();
    }

    $cutoff = time() - 300;
    $onlineStmt = $db->prepare("SELECT COUNT(*) FROM sessions WHERE last_active>?");
    $onlineStmt->execute([$cutoff]);
    $recording = [];
    $db->prepare("DELETE FROM recording_status WHERE expires_at<=?")->execute([time()]);
    if (featureValue($user, 'recording_status', false)) {
        $recordStmt = $db->prepare("SELECT u.id,u.username,u.color FROM recording_status r
            JOIN users u ON u.id=r.user_id WHERE r.group_key=? AND r.expires_at>? AND r.user_id!=?");
        $recordStmt->execute([groupKey($groupId), time(), $user['id']]);
        $recording = $recordStmt->fetchAll();
    }
    jsonResponse([
        'messages' => array_map('messagePayload', $rows),
        'online' => (int)$onlineStmt->fetchColumn(),
        'recording' => $recording,
        'groups' => groupsAvailableForUser($user) ? userGroups((int)$user['id']) : [],
        'groups_enabled' => groupsAvailableForUser($user),
        'groups_platform_enabled' => groupsEnabled(),
        'group_id' => $groupId,
        'server_time' => time(),
    ]);
}

function archiveDays(): never {
    $user = authRequired();
    $rows = personalArchiveRows($user, '', 1000);
    $days = array_values(array_unique(array_column($rows, 'day_key')));
    rsort($days);
    jsonResponse(['days' => $days]);
}