<?php
declare(strict_types=1);

function webImEnv(string $key, string $fallback = ''): string
{
    $runtimeValue = getenv($key);
    if ($runtimeValue !== false && $runtimeValue !== '') {
        return $runtimeValue;
    }

    static $env = null;
    if ($env === null) {
        $env = [];
        $paths = array_filter([
            getenv('JC_WEB_IM_ENV_FILE') ?: '',
            dirname(__DIR__, 2) . '/.env',
            '/var/www/im-admin/.env',
            '/var/www/im/.env',
        ]);

        foreach ($paths as $path) {
            if (!is_readable($path)) {
                continue;
            }
            foreach (file($path, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES) ?: [] as $line) {
                $line = trim($line);
                if ($line === '' || strpos($line, '#') === 0 || strpos($line, '=') === false) {
                    continue;
                }
                [$name, $value] = array_map('trim', explode('=', $line, 2));
                if ($name === '') {
                    continue;
                }
                $value = trim($value);
                if (
                    strlen($value) >= 2
                    && (($value[0] === '"' && substr($value, -1) === '"') || ($value[0] === "'" && substr($value, -1) === "'"))
                ) {
                    $value = substr($value, 1, -1);
                }
                $env[$name] = $value;
            }
            break;
        }
    }

    return $env[$key] ?? $fallback;
}

function webImFirstEnv(array $keys, string $fallback = ''): string
{
    foreach ($keys as $key) {
        $value = webImEnv($key);
        if ($value !== '') {
            return $value;
        }
    }
    return $fallback;
}

function webImMysqlDsn(string $host, string $port, string $database): string
{
    return sprintf('mysql:host=%s;port=%s;dbname=%s;charset=utf8mb4', $host, $port, $database);
}

define('IM_ADMIN_URL', webImEnv('JC_WEB_IM_ADMIN_URL', 'http://127.0.0.1:18080'));
define('IM_ADMIN_SECRET', webImFirstEnv(['JC_WEB_IM_ADMIN_SECRET', 'SecretKey'], '123456'));
define('IM_DB_DSN', webImMysqlDsn(
    webImEnv('JC_WEB_IM_DB_HOST', webImEnv('DB_HOST', '127.0.0.1')),
    webImEnv('JC_WEB_IM_DB_PORT', webImEnv('DB_PORT', '3306')),
    webImEnv('JC_WEB_IM_DB_DATABASE', webImEnv('DB_DATABASE', 'wfchat'))
));
define('IM_DB_USER', webImEnv('JC_WEB_IM_DB_USER', webImEnv('DB_USERNAME', 'winchen')));
define('IM_DB_PASSWORD', webImEnv('JC_WEB_IM_DB_PASSWORD', webImEnv('DB_PASSWORD', 'winchen@0904')));
define('IM_APP_DB_DSN', webImMysqlDsn(
    webImFirstEnv(['JC_WEB_IM_APP_DB_HOST', 'DB_HOST_2', 'DB_HOST2_2'], webImEnv('DB_HOST', '127.0.0.1')),
    webImFirstEnv(['JC_WEB_IM_APP_DB_PORT', 'DB_PORT_2', 'DB_PORT2_2'], webImEnv('DB_PORT', '3306')),
    webImFirstEnv(['JC_WEB_IM_APP_DB_DATABASE', 'DB_DATABASE_2', 'DB_DATABASE2_2'], webImEnv('DB_DATABASE', 'appdata'))
));
define('IM_APP_DB_USER', webImFirstEnv(['JC_WEB_IM_APP_DB_USER', 'DB_USERNAME_2', 'DB_USERNAME2_2'], webImEnv('DB_USERNAME', 'winchen')));
define('IM_APP_DB_PASSWORD', webImFirstEnv(['JC_WEB_IM_APP_DB_PASSWORD', 'DB_PASSWORD_2', 'DB_PASSWORD2_2'], webImEnv('DB_PASSWORD', 'winchen@0904')));
define('IM_DB_TIMEZONE', webImEnv('JC_WEB_IM_DB_TIMEZONE', 'Asia/Bangkok'));

function respond(int $code, string $message, array $result = []): void
{
    echo json_encode([
        'code' => $code,
        'message' => $message,
        'result' => $result,
    ], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
    exit;
}

function readJsonPayload(): array
{
    $payload = json_decode(file_get_contents('php://input') ?: '[]', true);
    return is_array($payload) ? $payload : [];
}

function imAdminPost(string $path, array $payload): array
{
    $nonce = (string)random_int(1, 1000000);
    $timestamp = (string)((int)floor(microtime(true) * 1000));
    $sign = sha1($nonce . '|' . IM_ADMIN_SECRET . '|' . $timestamp);
    $body = json_encode($payload, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);

    $curl = curl_init(IM_ADMIN_URL . $path);
    if ($curl === false) {
        throw new RuntimeException('IM admin client init failed');
    }

    curl_setopt_array($curl, [
        CURLOPT_POST => true,
        CURLOPT_POSTFIELDS => $body,
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_0,
        CURLOPT_CONNECTTIMEOUT_MS => 1000,
        CURLOPT_TIMEOUT_MS => 4000,
        CURLOPT_FRESH_CONNECT => true,
        CURLOPT_FORBID_REUSE => true,
        CURLOPT_HTTPHEADER => [
            'Content-Type: application/json; charset=utf-8',
            'Connection: close',
            'nonce: ' . $nonce,
            'timestamp: ' . $timestamp,
            'sign: ' . $sign,
        ],
    ]);

    $responseBody = curl_exec($curl);
    $curlError = curl_error($curl);
    curl_close($curl);

    if ($responseBody === false || $responseBody === '') {
        throw new RuntimeException($curlError ?: 'IM admin request failed');
    }

    $data = json_decode($responseBody, true);
    if (!is_array($data)) {
        throw new RuntimeException('Invalid IM admin response');
    }

    return $data;
}

function requireImSuccess(array $response, string $fallbackMessage): array
{
    if (($response['code'] ?? -1) !== 0) {
        throw new RuntimeException((string)($response['msg'] ?? $response['message'] ?? $fallbackMessage));
    }

    return is_array($response['result'] ?? null) ? $response['result'] : [];
}

function imDb(): PDO
{
    static $pdo = null;
    if ($pdo instanceof PDO) {
        return $pdo;
    }

    $pdo = new PDO(IM_DB_DSN, IM_DB_USER, IM_DB_PASSWORD, [
        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        PDO::ATTR_EMULATE_PREPARES => false,
    ]);

    return $pdo;
}

function imAppDb(): PDO
{
    static $pdo = null;
    if ($pdo instanceof PDO) {
        return $pdo;
    }

    $pdo = new PDO(IM_APP_DB_DSN, IM_APP_DB_USER, IM_APP_DB_PASSWORD, [
        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        PDO::ATTR_EMULATE_PREPARES => false,
    ]);

    return $pdo;
}

function ensureWebImAppTables(): void
{
    static $ensured = false;
    if ($ensured) {
        return;
    }
    $ensured = true;

    $db = imAppDb();
    $db->exec(
        "create table if not exists `t_web_groups` (
            `id` bigint unsigned not null auto_increment,
            `group_id` varchar(64) not null,
            `category` varchar(20) not null default 'group',
            `name` varchar(128) not null,
            `portrait` varchar(1024) not null default '',
            `owner_uid` varchar(64) not null,
            `join_mode` varchar(20) not null default 'open',
            `announcement` text null,
            `native_group_id` varchar(64) not null default '',
            `native_status` varchar(32) not null default 'pending',
            `native_error` varchar(255) not null default '',
            `created_by` varchar(64) not null,
            `created_at_ms` bigint not null,
            `updated_at_ms` bigint not null,
            `deleted` tinyint not null default 0,
            primary key (`id`),
            unique key `uk_t_web_groups_group_id` (`group_id`),
            key `idx_t_web_groups_owner` (`owner_uid`),
            key `idx_t_web_groups_category` (`category`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
    try {
        $db->exec("alter table `t_web_groups` add column `welcome_text` text null after `announcement`");
    } catch (Throwable) {
    }
    $db->exec(
        "create table if not exists `t_web_group_members` (
            `id` bigint unsigned not null auto_increment,
            `group_id` varchar(64) not null,
            `user_id` varchar(64) not null,
            `role` varchar(20) not null default 'member',
            `alias` varchar(128) not null default '',
            `joined_at_ms` bigint not null,
            `updated_at_ms` bigint not null,
            `status` tinyint not null default 0,
            primary key (`id`),
            unique key `uk_t_web_group_members_gid_uid` (`group_id`, `user_id`),
            key `idx_t_web_group_members_user` (`user_id`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
    $db->exec(
        "create table if not exists `t_web_group_messages` (
            `id` bigint unsigned not null auto_increment,
            `message_uid` varchar(64) not null,
            `group_id` varchar(64) not null,
            `sender_uid` varchar(64) not null,
            `text` text not null,
            `created_at_ms` bigint not null,
            `edited_at_ms` bigint not null default 0,
            `recalled` tinyint not null default 0,
            primary key (`id`),
            unique key `uk_t_web_group_messages_uid` (`message_uid`),
            key `idx_t_web_group_messages_group_time` (`group_id`, `created_at_ms`),
            key `idx_t_web_group_messages_sender` (`sender_uid`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
    $db->exec(
        "create table if not exists `t_web_message_attachments` (
            `id` bigint unsigned not null auto_increment,
            `message_uid` varchar(64) not null,
            `conversation_type` varchar(16) not null default 'single',
            `target_id` varchar(128) not null default '',
            `sender_uid` varchar(64) not null default '',
            `attachment_type` varchar(16) not null,
            `url` varchar(1024) not null,
            `name` varchar(255) not null default '',
            `mime` varchar(128) not null default '',
            `size_bytes` bigint not null default 0,
            `created_at_ms` bigint not null,
            primary key (`id`),
            unique key `uk_t_web_message_attachments_uid` (`message_uid`),
            key `idx_t_web_message_attachments_target` (`conversation_type`, `target_id`, `created_at_ms`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
    $db->exec(
        "create table if not exists `t_web_group_reads` (
            `id` bigint unsigned not null auto_increment,
            `group_id` varchar(64) not null,
            `user_id` varchar(64) not null,
            `read_at_ms` bigint not null default 0,
            `updated_at_ms` bigint not null,
            primary key (`id`),
            unique key `uk_t_web_group_reads_gid_uid` (`group_id`, `user_id`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
    $db->exec(
        "create table if not exists `t_web_group_mute_rules` (
            `id` bigint unsigned not null auto_increment,
            `group_id` varchar(64) not null,
            `mode` varchar(32) not null default 'off',
            `schedule_type` varchar(16) not null default 'once',
            `starts_at_ms` bigint not null default 0,
            `ends_at_ms` bigint not null default 0,
            `daily_start` varchar(8) not null default '',
            `daily_end` varchar(8) not null default '',
            `enabled` tinyint not null default 0,
            `created_by` varchar(64) not null default '',
            `updated_at_ms` bigint not null,
            primary key (`id`),
            unique key `uk_t_web_group_mute_rules_group` (`group_id`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
    $db->exec(
        "create table if not exists `t_web_broadcast_logs` (
            `id` bigint unsigned not null auto_increment,
            `sender_uid` varchar(64) not null,
            `target_count` int not null default 0,
            `success_count` int not null default 0,
            `failed_count` int not null default 0,
            `text` text not null,
            `target_json` text null,
            `result_json` text null,
            `created_at_ms` bigint not null,
            primary key (`id`),
            key `idx_t_web_broadcast_logs_sender_time` (`sender_uid`, `created_at_ms`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
    $db->exec(
        "create table if not exists `t_web_user_remarks` (
            `id` bigint unsigned not null auto_increment,
            `owner_uid` varchar(64) not null,
            `target_uid` varchar(64) not null,
            `alias` varchar(128) not null default '',
            `created_at_ms` bigint not null,
            `updated_at_ms` bigint not null,
            primary key (`id`),
            unique key `uk_t_web_user_remarks_owner_target` (`owner_uid`, `target_uid`),
            key `idx_t_web_user_remarks_target` (`target_uid`)
        ) engine=InnoDB default charset=utf8mb4 collate=utf8mb4_unicode_ci"
    );
}

function webImPlaceholders(array $values): string
{
    return implode(',', array_fill(0, count($values), '?'));
}

function fetchWebUserRemarkMap(PDO $db, string $ownerId, array $targetIds): array
{
    $targetIds = array_values(array_unique(array_filter(array_map(static function ($targetId): string {
        return trim((string)$targetId);
    }, $targetIds))));
    if ($ownerId === '' || !$targetIds) {
        return [];
    }

    $statement = $db->prepare(
        'select `target_uid`, `alias` from `t_web_user_remarks`'
        . ' where `owner_uid` = ? and `target_uid` in (' . webImPlaceholders($targetIds) . ')'
    );
    $statement->execute(array_merge([$ownerId], $targetIds));

    $remarks = [];
    foreach ($statement->fetchAll() as $row) {
        $remarks[(string)$row['target_uid']] = trim((string)($row['alias'] ?? ''));
    }

    return $remarks;
}

function fetchImFriendAliasMap(PDO $db, string $ownerId, array $friendIds): array
{
    $friendIds = array_values(array_unique(array_filter(array_map(static function ($friendId): string {
        return trim((string)$friendId);
    }, $friendIds))));
    if ($ownerId === '' || !$friendIds) {
        return [];
    }

    $aliases = [];
    foreach (array_chunk($friendIds, 500) as $chunk) {
        $statement = $db->prepare(
            'select `_friend_uid`, `_alias` from `t_friend`'
            . ' where `_uid` = ? and `_friend_uid` in (' . webImPlaceholders($chunk) . ') and `_state` = 0'
        );
        $statement->execute(array_merge([$ownerId], $chunk));

        foreach ($statement->fetchAll() as $row) {
            $aliases[(string)$row['_friend_uid']] = trim((string)($row['_alias'] ?? ''));
        }
    }

    return $aliases;
}

function saveWebUserRemark(PDO $db, string $ownerId, string $targetId, string $alias): void
{
    if ($ownerId === '' || $targetId === '') {
        return;
    }

    if ($alias === '') {
        $delete = $db->prepare('delete from `t_web_user_remarks` where `owner_uid` = ? and `target_uid` = ?');
        $delete->execute([$ownerId, $targetId]);
        return;
    }

    $now = webImNowMs();
    $statement = $db->prepare(
        'insert into `t_web_user_remarks` (`owner_uid`, `target_uid`, `alias`, `created_at_ms`, `updated_at_ms`)'
        . ' values (?, ?, ?, ?, ?)'
        . ' on duplicate key update `alias` = values(`alias`), `updated_at_ms` = values(`updated_at_ms`)'
    );
    $statement->execute([$ownerId, $targetId, $alias, $now, $now]);
}

function webImNowMs(): int
{
    return (int)floor(microtime(true) * 1000);
}

function webImMessageUid(): string
{
    $timestampPart = (webImNowMs() - 1514736000000) << 21;
    return (string)($timestampPart | random_int(1, 0x1FFFFF));
}

function javaStringHashCode(string $value): int
{
    $hash = 0;
    $length = strlen($value);
    for ($i = 0; $i < $length; $i++) {
        $hash = (31 * $hash + ord($value[$i])) & 0xFFFFFFFF;
        if ($hash >= 0x80000000) {
            $hash -= 0x100000000;
        }
    }

    return $hash;
}

function imUserMessagesTable(string $userId): string
{
    return 't_user_messages_' . (abs(javaStringHashCode($userId)) % 128);
}

function imMessageTable(string $messageId): string
{
    $timestamp = ((int)$messageId >> 21) + 1514736000000;
    $date = (new DateTimeImmutable('@' . (int)floor($timestamp / 1000)))
        ->setTimezone(new DateTimeZone(IM_DB_TIMEZONE));
    $year = (int)$date->format('Y');
    $month = (int)$date->format('n') - 1;

    return 't_messages_' . (($year % 3) * 12 + $month);
}