<?php

namespace App\Http\Controllers\Admin;

use App\DB\Te\TableEngine;
use App\Http\Controllers\Controller;
use App\Models\AppNotification;
use App\Models\AppNotificationRead;
use App\Models\AppNotificationRecipient;
use App\Models\Customer;
use App\Services\AppNotificationAudienceService;
use App\Services\PriceStreamService;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;

class AppNotificationController extends Controller
{
    public function table(Request $request)
    {
        $query = AppNotification::query()->withCount('reads');

        TableEngine::create($query, $request->all())
            ->initSearch(['title', 'body', 'severity', 'audience_label', 'audience_type'])
            ->select(['*'])
            ->export($query);

        return $query;
    }

    public function audienceOptions()
    {
        return response()->json([
            'segments' => app(AppNotificationAudienceService::class)->segmentOptions(),
        ]);
    }

    public function searchCustomers(Request $request)
    {
        $q = trim((string) $request->get('q', ''));

        $rows = Customer::query()
            ->where('type', 2)
            ->where('is_archive', false)
            ->when($q !== '', function ($query) use ($q) {
                $query->where(function ($inner) use ($q) {
                    $inner->where('name', 'like', '%' . $q . '%')
                        ->orWhere('mobile', 'like', '%' . $q . '%')
                        ->orWhere('id', $q);
                });
            })
            ->orderByDesc('id')
            ->limit(30)
            ->get(['id', 'name', 'mobile']);

        return response()->json(['customers' => $rows]);
    }

    public function previewAudience(Request $request)
    {
        $audience = app(AppNotificationAudienceService::class);
        $type = (string) $request->input('audience_type', AppNotificationAudienceService::TYPE_ALL);
        $segmentKeys = array_values(array_filter((array) $request->input('segment_keys', [])));
        $customerIds = array_values(array_filter(array_map('intval', (array) $request->input('customer_ids', []))));

        $customers = match ($type) {
            AppNotificationAudienceService::TYPE_SEGMENT => $audience->resolveSegmentCustomers($segmentKeys),
            AppNotificationAudienceService::TYPE_CUSTOMERS => $audience->resolveCustomersByIds($customerIds),
            default => collect(),
        };

        return response()->json([
            'count' => $type === AppNotificationAudienceService::TYPE_ALL ? null : $customers->count(),
            'sample' => $customers->take(20)->values(),
            'label' => $audience->buildAudienceLabel($type, $segmentKeys, $customers->count()),
        ]);
    }

    public function store(Request $request)
    {
        $data = $this->validatedPayload($request);
        $audience = app(AppNotificationAudienceService::class);

        $audienceType = (string) ($data['audience_type'] ?? AppNotificationAudienceService::TYPE_ALL);
        $segmentKeys = array_values(array_filter((array) ($data['segment_keys'] ?? [])));
        $customerIds = array_values(array_filter(array_map('intval', (array) ($data['customer_ids'] ?? []))));

        $recipients = match ($audienceType) {
            AppNotificationAudienceService::TYPE_SEGMENT => $audience->resolveSegmentCustomers($segmentKeys),
            AppNotificationAudienceService::TYPE_CUSTOMERS => $audience->resolveCustomersByIds($customerIds),
            default => collect(),
        };

        if ($audienceType === AppNotificationAudienceService::TYPE_SEGMENT && $recipients->isEmpty()) {
            return response()->json(['message' => 'برای گروه انتخاب‌شده مشتری‌ای یافت نشد.'], 422);
        }
        if ($audienceType === AppNotificationAudienceService::TYPE_CUSTOMERS && $recipients->isEmpty()) {
            return response()->json(['message' => 'حداقل یک مشتری انتخاب کنید.'], 422);
        }

        $recipientsCount = $audienceType === AppNotificationAudienceService::TYPE_ALL
            ? 0
            : $recipients->count();

        $row = DB::transaction(function () use ($data, $audience, $audienceType, $segmentKeys, $recipients, $recipientsCount) {
            $user = auth()->user();

            $row = AppNotification::create([
                'title' => $data['title'],
                'body' => $data['body'],
                'severity' => $data['severity'],
                'is_active' => $data['is_active'] ?? true,
                'created_by' => $user?->id,
                'audience_type' => $audienceType,
                'segment_keys' => $audienceType === AppNotificationAudienceService::TYPE_SEGMENT ? $segmentKeys : null,
                'audience_label' => $audience->buildAudienceLabel($audienceType, $segmentKeys, $recipientsCount),
                'recipients_count' => $recipientsCount,
            ]);

            if ($audienceType !== AppNotificationAudienceService::TYPE_ALL) {
                $now = now();
                $chunks = $recipients->pluck('id')->map(fn ($id) => [
                    'notification_id' => $row->id,
                    'customer_id' => (int) $id,
                    'created_at' => $now,
                    'updated_at' => $now,
                ])->chunk(500);

                foreach ($chunks as $chunk) {
                    AppNotificationRecipient::query()->insert($chunk->values()->all());
                }
            }

            return $row;
        });

        $this->broadcastNotification($row);

        return response()->json($row->fresh(), 201);
    }

    public function update(Request $request, int $id)
    {
        $row = AppNotification::findOrFail($id);
        // مخاطب بعد از ارسال ثابت می‌ماند — فقط محتوا/وضعیت
        $data = $request->validate([
            'title' => 'sometimes|required|string|max:191',
            'body' => 'sometimes|required|string|max:5000',
            'severity' => 'sometimes|required|in:info,success,warning,danger',
            'is_active' => 'sometimes|boolean',
        ]);
        $row->update($data);

        return response()->json(true);
    }

    public function toggleActive(int $id)
    {
        $row = AppNotification::findOrFail($id);
        $row->is_active = ! $row->is_active;
        $row->save();

        return response()->json([
            'is_active' => (bool) $row->is_active,
        ]);
    }

    public function destroy(int $id)
    {
        $row = AppNotification::findOrFail($id);
        AppNotificationRecipient::query()->where('notification_id', $id)->delete();
        $row->delete();

        return response()->json(true);
    }

    /** بازدیدکنندگان (خوانده‌اند) */
    public function readers(int $id)
    {
        AppNotification::findOrFail($id);

        $rows = AppNotificationRead::query()
            ->where('notification_id', $id)
            ->with(['customer:id,name,fname,lname,mobile'])
            ->orderByDesc('read_at')
            ->orderByDesc('id')
            ->get();

        $readers = $rows->map(function (AppNotificationRead $read) {
            $customer = $read->customer;
            $name = trim((string) ($customer?->name ?: trim(($customer?->fname ?? '') . ' ' . ($customer?->lname ?? ''))));

            return [
                'customer_id' => $read->customer_id,
                'name' => $name !== '' ? $name : '—',
                'mobile' => $customer?->mobile,
                'read_at' => $read->read_at,
            ];
        })->values();

        return response()->json([
            'reads_count' => $readers->count(),
            'readers' => $readers,
        ]);
    }

    /** گیرندگان هدف (اسنپ‌شات ارسال) */
    public function recipients(int $id)
    {
        $row = AppNotification::findOrFail($id);

        if ($row->audience_type === AppNotificationAudienceService::TYPE_ALL) {
            return response()->json([
                'audience_type' => $row->audience_type,
                'audience_label' => $row->audience_label ?: 'همه کاربران',
                'recipients_count' => null,
                'recipients' => [],
                'note' => 'این اعلان برای همه کاربران فعال ارسال شده است.',
            ]);
        }

        $rows = AppNotificationRecipient::query()
            ->where('notification_id', $id)
            ->with(['customer:id,name,fname,lname,mobile'])
            ->orderByDesc('id')
            ->limit(500)
            ->get();

        $recipients = $rows->map(function (AppNotificationRecipient $item) {
            $customer = $item->customer;
            $name = trim((string) ($customer?->name ?: trim(($customer?->fname ?? '') . ' ' . ($customer?->lname ?? ''))));

            return [
                'customer_id' => $item->customer_id,
                'name' => $name !== '' ? $name : '—',
                'mobile' => $customer?->mobile,
            ];
        })->values();

        return response()->json([
            'audience_type' => $row->audience_type,
            'audience_label' => $row->audience_label,
            'recipients_count' => (int) $row->recipients_count,
            'recipients' => $recipients,
        ]);
    }

    private function validatedPayload(Request $request): array
    {
        return $request->validate([
            'title' => 'required|string|max:191',
            'body' => 'required|string|max:5000',
            'severity' => 'required|in:info,success,warning,danger',
            'is_active' => 'sometimes|boolean',
            'audience_type' => 'required|in:all,segment,customers',
            'segment_keys' => 'nullable|array',
            'segment_keys.*' => 'string',
            'customer_ids' => 'nullable|array',
            'customer_ids.*' => 'integer',
        ]);
    }

    private function broadcastNotification(AppNotification $row): void
    {
        if (! $row->is_active) {
            return;
        }

        $payload = [
            'id' => $row->id,
            'title' => $row->title,
            'body' => $row->body,
            'severity' => $row->severity,
            'created_at' => optional($row->created_at)?->toIso8601String(),
        ];

        $stream = app(PriceStreamService::class);

        if ($row->audience_type === AppNotificationAudienceService::TYPE_ALL) {
            $stream->publish('app_notification', $payload);

            return;
        }

        $ids = AppNotificationRecipient::query()
            ->where('notification_id', $row->id)
            ->pluck('customer_id');

        foreach ($ids as $customerId) {
            $stream->publishForCustomer((int) $customerId, 'app_notification', $payload);
        }
    }
}