<?php

namespace app\support;

use support\think\Db;

class MessageDispatcher
{
    public function sendInboxEvent(string $eventCode, array $context): bool
    {
        $userId = (int)($context['user_id'] ?? 0);
        $bizType = trim((string)($context['biz_type'] ?? ''));
        $bizId = (int)($context['biz_id'] ?? 0);

        if ($userId <= 0 || $bizType === '' || $bizId <= 0) {
            return false;
        }

        if (!$this->shouldSendByPreference($userId, $eventCode)) {
            return false;
        }

        $rule = Db::name('message_rules')
            ->where('event_code', $eventCode)
            ->where('channel', 'inbox')
            ->where('is_enabled', 1)
            ->order('id', 'asc')
            ->find();

        if (!$rule) {
            $disabledRule = Db::name('message_rules')
                ->where('event_code', $eventCode)
                ->where('channel', 'inbox')
                ->find();

            if ($disabledRule) {
                return false;
            }
        }

        $template = null;
        if ($rule) {
            $template = Db::name('message_templates')
                ->where('id', (int)$rule['template_id'])
                ->where('channel', 'inbox')
                ->where('is_enabled', 1)
                ->find();
        }

        $alreadySent = Db::name('message_logs')
            ->where('user_id', $userId)
            ->where('biz_type', $bizType)
            ->where('biz_id', $bizId)
            ->where('channel', 'inbox')
            ->where('status', 'sent')
            ->find();

        if ($alreadySent) {
            return false;
        }

        $title = $this->renderTemplate(
            $template['title'] ?? (string)($context['fallback_title'] ?? ''),
            $context
        );
        $content = $this->renderTemplate(
            $template['content'] ?? (string)($context['fallback_content'] ?? ''),
            $context
        );

        if ($title === '' && $content === '') {
            return false;
        }

        $now = date('Y-m-d H:i:s');

        Db::name('user_messages')->insert([
            'user_id' => $userId,
            'title' => $title !== '' ? $title : '系统通知',
            'content' => $content,
            'biz_type' => $bizType,
            'biz_id' => $bizId,
            'is_read' => 0,
            'read_at' => null,
            'created_at' => $now,
            'updated_at' => $now,
        ]);

        Db::name('message_logs')->insert([
            'user_id' => $userId,
            'template_id' => $template['id'] ?? null,
            'biz_type' => $bizType,
            'biz_id' => $bizId,
            'channel' => 'inbox',
            'status' => 'sent',
            'fail_reason' => '',
            'sent_at' => $now,
            'created_at' => $now,
            'updated_at' => $now,
        ]);

        return true;
    }

    private function shouldSendByPreference(int $userId, string $eventCode): bool
    {
        $preferenceKey = $this->preferenceKeyForEvent($eventCode);
        if ($preferenceKey === '') {
            return true;
        }

        $configValue = Db::name('system_configs')
            ->where('config_group', 'user_settings')
            ->where('config_key', 'user_' . $userId)
            ->value('config_value');

        if (!is_string($configValue) || $configValue === '') {
            return $this->defaultPreference($preferenceKey);
        }

        $decoded = json_decode($configValue, true);
        if (!is_array($decoded)) {
            return $this->defaultPreference($preferenceKey);
        }

        if (!array_key_exists($preferenceKey, $decoded)) {
            return $this->defaultPreference($preferenceKey);
        }

        return (bool)$decoded[$preferenceKey];
    }

    private function preferenceKeyForEvent(string $eventCode): string
    {
        return match ($eventCode) {
            'order_created' => 'notify_order',
            'return_shipped' => 'notify_order',
            'return_received' => 'notify_order',
            'report_published' => 'notify_report',
            'supplement_required' => 'notify_supplement',
            'ticket_reply', 'ticket_waiting_user', 'ticket_resolved', 'ticket_closed' => 'notify_ticket',
            default => '',
        };
    }

    private function defaultPreference(string $key): bool
    {
        return match ($key) {
            'marketing_notify', 'privacy_mode' => false,
            default => true,
        };
    }

    private function renderTemplate(string $text, array $context): string
    {
        if ($text === '') {
            return '';
        }

        return preg_replace_callback('/\{\{\s*([a-zA-Z0-9_]+)\s*\}\}/', function (array $matches) use ($context) {
            $key = $matches[1];
            if (!array_key_exists($key, $context)) {
                return '';
            }

            $value = $context[$key];
            if (is_scalar($value) || $value === null) {
                return (string)$value;
            }

            return '';
        }, $text) ?? $text;
    }
}