<?php

namespace base\common\service;

use app\admin\model\SystemNotice;
use base\admin\model\SystemNoticeTargetBase;
use base\common\notice\channel\EmailChannel;
use base\common\notice\channel\InMailChannel;
use base\common\notice\channel\SmsChannel;
use base\common\notice\channel\WechatChannel;
use think\facade\Db;
use think\facade\Event;
use think\facade\Log;

/**
 * 通知服务（内核层）.
 *
 * 统一发送入口：写 system_notice 主体 + 按 admin×渠道展开 system_notice_target 投递行。
 * 站内信（inmail）行直接置成功终态即完成投递（投递即落库）；
 * 其余渠道行置待发送，由 timer 异步消费者按渠道驱动投递。
 *
 * 场景（scene）为代码级注册表（scenes()），不建数据库表；
 * app 层入口类可 override scenes()/channels() 做覆盖合并，
 * 如：return array_merge(parent::scenes(), ['my_scene' => [...]]);
 */
class NoticeServiceBase
{
    /** 渠道标识：站内信 */
    public const CHANNEL_INMAIL = 'inmail';

    /** 渠道标识：邮件 */
    public const CHANNEL_EMAIL = 'email';

    /** 渠道标识：短信 */
    public const CHANNEL_SMS = 'sms';

    /** 渠道标识：公众号 */
    public const CHANNEL_WECHAT = 'wechat';

    /**
     * 场景注册表（代码级，app 层可覆盖合并）.
     *
     * 每项含 title（展示名）/ channels（该场景允许投递的渠道）/ locked（强制必选，
     * 订阅不可关闭，发送侧豁免订阅过滤）。locked 不豁免渠道 ∩ 规则：
     * 强投递同样仅限场景注册渠道。
     */
    public static function scenes(): array
    {
        return [
            'system' => ['title' => '系统公告', 'channels' => [self::CHANNEL_INMAIL], 'locked' => true],
            'common' => ['title' => '通用通知', 'channels' => [self::CHANNEL_INMAIL, self::CHANNEL_EMAIL], 'locked' => false],
            'admin_login' => ['title' => '登录提醒', 'channels' => [self::CHANNEL_INMAIL, self::CHANNEL_EMAIL], 'locked' => false],
            'mall_stock' => ['title' => '库存预警', 'channels' => [self::CHANNEL_INMAIL, self::CHANNEL_EMAIL], 'locked' => false],
        ];
    }

    /**
     * 渠道驱动映射（class-string，延迟实例化）.
     *
     * email/sms/wechat 驱动类由后续任务提供类文件；class-string 字面量
     * 为编译期解析，不触发 autoload，本任务内无实例化路径，映射先行声明安全。
     */
    public static function channels(): array
    {
        return [
            self::CHANNEL_INMAIL => InMailChannel::class,
            self::CHANNEL_EMAIL => EmailChannel::class,
            self::CHANNEL_SMS => SmsChannel::class,
            self::CHANNEL_WECHAT => WechatChannel::class,
        ];
    }

    /**
     * 统一发送通知.
     *
     * 渠道解析规则（统一口径）：
     *  - 实际投递渠道 = options.channels ?? 注册场景的 scene.channels ?? [inmail]
     *  - 注册场景再 ∩ scene.channels（保序）；locked 强投递同样仅限场景注册渠道
     *  - 未注册场景跳过 ∩，缺省 [inmail]，并记 warning 放行
     *
     * @param array|int|string $adminIds 管理员ID数组、单个ID或 'all'（status=1 全体）
     * @param string           $title    标题
     * @param string           $content  内容
     * @param array            $options  scene（缺省 common）/channels/biz_id/send_admin_id
     * @return int 通知ID（system_notice.id）
     */
    public static function send(array|int|string $adminIds, string $title, string $content, array $options = []): int
    {
        $scene = (string) ($options['scene'] ?? 'common');
        $scenes = static::scenes();
        $registered = isset($scenes[$scene]);

        if (!$registered) {
            Log::warning('notice send: unregistered scene, fallback to default channels', ['scene' => $scene]);
        }

        // 渠道解析：第一段 = options.channels ?? 注册场景的 scene.channels ?? [inmail]
        if (isset($options['channels'])) {
            $channels = array_values(array_unique(array_map('strval', (array) $options['channels'])));
        } elseif ($registered) {
            $channels = array_map('strval', $scenes[$scene]['channels']);
        } else {
            $channels = [self::CHANNEL_INMAIL];
        }

        // 渠道解析：第二段 = 注册场景再 ∩ scene.channels（保序），locked 不豁免
        if ($registered) {
            $channels = array_values(array_intersect($channels, $scenes[$scene]['channels']));
        }

        if ($adminIds === 'all') {
            $adminIds = Db::name('system_admin')->where('status', 1)->column('id');
        } else {
            $adminIds = array_values(array_unique(array_map('intval', (array) $adminIds)));
        }

        $now = time();

        $notice = SystemNotice::create([
            'scene' => $scene,
            'title' => $title,
            'content' => $content,
            'biz_id' => (string) ($options['biz_id'] ?? ''),
            'send_admin_id' => (int) ($options['send_admin_id'] ?? 0),
        ]);
        $noticeId = (int) $notice->id;

        $targets = [];
        if ($adminIds !== []) {
            $targets = static::buildTargets($noticeId, $adminIds, $scene, $channels, $registered, $now);
            if ($targets !== []) {
                Db::name('system_notice_target')->insertAll($targets);
            }
        }

        Event::trigger('NoticeSended', [$notice, $targets]);

        return $noticeId;
    }

    /**
     * 展开投递行：对每个 admin×每个实际渠道做订阅过滤与地址解析.
     *
     * @param int   $noticeId   通知ID
     * @param array $adminIds   管理员ID列表
     * @param string $scene     场景
     * @param array $channels   解析后的实际投递渠道（可能为空数组）
     * @param bool  $registered 场景是否已注册（决定 locked 语义是否生效）
     * @param int   $now        时间戳
     * @return array 投递行列表（insertAll 格式）
     */
    protected static function buildTargets(int $noticeId, array $adminIds, string $scene, array $channels, bool $registered, int $now): array
    {
        if ($channels === []) {
            return [];
        }

        $locked = $registered && !empty(static::scenes()[$scene]['locked']);

        // inmail 全局总闸：sysconfig('notify','notify_inmail_enable') 严格等于 0 时关闭；
        // 键不存在（null/缺省 1）视为开。DB value 为字符串，须强转 int 后比较。
        $inmailEnabled = true;
        if (in_array(self::CHANNEL_INMAIL, $channels, true)) {
            $inmailEnabled = (int) sysconfig('notify', 'notify_inmail_enable', 1) !== 0;
        }

        // 一次取齐 email 地址映射（email 渠道地址 = admin.email）
        $adminEmailMap = Db::name('system_admin')
            ->whereIn('id', $adminIds)
            ->column('email', 'id');

        $targets = [];
        foreach ($adminIds as $adminId) {
            $adminId = (int) $adminId;
            foreach ($channels as $channel) {
                // locked 场景强制投递；否则按订阅矩阵过滤（status=0 退订即跳过该渠道）
                if (!$locked && !static::isSubscribed($adminId, $scene, $channel)) {
                    continue;
                }

                $targetAddr = '';
                if ($channel === self::CHANNEL_EMAIL) {
                    $targetAddr = (string) ($adminEmailMap[$adminId] ?? '');
                    if ($targetAddr === '') {
                        Log::info('notice send: skip email channel, admin has no email', ['admin_id' => $adminId, 'notice_id' => $noticeId]);
                        continue;
                    }
                }

                if ($channel === self::CHANNEL_INMAIL && !$inmailEnabled) {
                    continue;
                }

                // inmail 直接置成功终态（投递即落库），其余渠道待消费者投递
                $isInmail = $channel === self::CHANNEL_INMAIL;
                $status = $isInmail ? SystemNoticeTargetBase::STATUS_SUCCESS : SystemNoticeTargetBase::STATUS_PENDING;

                $targets[] = [
                    'notice_id' => $noticeId,
                    'admin_id' => $adminId,
                    'channel' => $channel,
                    'target_addr' => $targetAddr,
                    'status' => $status,
                    'send_time' => $isInmail ? $now : 0,
                    'read_time' => 0,
                    'create_time' => $now,
                    'update_time' => $now,
                ];
            }
        }

        return $targets;
    }

    /**
     * 是否订阅指定场景渠道.
     *
     * locked 场景恒 true；subscribe 表无记录视为默认订阅；
     * 仅 status=0（显式退订）返回 false。
     */
    public static function isSubscribed(int $adminId, string $scene, string $channel): bool
    {
        $scenes = static::scenes();
        if (isset($scenes[$scene]) && !empty($scenes[$scene]['locked'])) {
            return true;
        }

        $status = Db::name('system_notice_subscribe')
            ->where('admin_id', $adminId)
            ->where('scene', $scene)
            ->where('channel', $channel)
            ->value('status');

        if ($status === null) {
            return true;
        }

        return (int) $status === 1;
    }

    /**
     * 未读站内信数（channel=inmail AND read_time=0 AND status=2，走复合索引）.
     */
    public static function unreadCount(int $adminId): int
    {
        return Db::name('system_notice_target')
            ->where('admin_id', $adminId)
            ->where('channel', self::CHANNEL_INMAIL)
            ->where('read_time', 0)
            ->where('status', SystemNoticeTargetBase::STATUS_SUCCESS)
            ->count();
    }

    /**
     * 标记站内信已读（带 admin_id 条件防越权）.
     *
     * @param array $targetIds 投递行ID列表
     * @param int   $adminId   当前管理员
     * @return int 实际标记的行数
     */
    public static function markRead(array $targetIds, int $adminId): int
    {
        if ($targetIds === []) {
            return 0;
        }

        return Db::name('system_notice_target')
            ->where('admin_id', $adminId)
            ->whereIn('id', $targetIds)
            ->where('read_time', 0)
            ->update(['read_time' => time()]);
    }

    /**
     * 全部站内信标记已读（带 admin_id 条件防越权）.
     *
     * @return int 实际标记的行数
     */
    public static function markAllRead(int $adminId): int
    {
        return Db::name('system_notice_target')
            ->where('admin_id', $adminId)
            ->where('channel', self::CHANNEL_INMAIL)
            ->where('read_time', 0)
            ->update(['read_time' => time()]);
    }
}