<?php

declare(strict_types=1);

namespace App\Http\Controllers\Api\Admin\MailCampaign\Concerns;

use App\Jobs\Mail\SendMailCampaignRecipient;
use App\Models\Mail;
use App\Models\MailCampaign;
use Illuminate\Database\Eloquent\Collection;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;

trait HandlesCampaignBulkActions
{
    public function bulkAction(Request $request): JsonResponse
    {
        $data = $request->validate([
            'action'  => 'required|in:cancel,retry-failed',
            'uuids'   => 'required|array|min:1|max:200',
            'uuids.*' => 'string',
        ]);

        $campaigns = MailCampaign::whereIn('uuid', $data['uuids'])->get();

        $message = $data['action'] === 'cancel'
            ? $this->cancelCampaigns($campaigns)
            : $this->retryFailedRecipients($campaigns);

        return response()->json(['error' => false, 'message' => $message]);
    }

    public function bulkDelete(Request $request): JsonResponse
    {
        $data = $request->validate([
            'uuids'   => 'required|array|min:1|max:200',
            'uuids.*' => 'string',
        ]);

        $deleted = MailCampaign::whereIn('uuid', $data['uuids'])
            ->whereIn('status', MailCampaign::FINISHED_STATUSES)
            ->delete();
        $skipped = count($data['uuids']) - $deleted;

        return response()->json([
            'error'   => false,
            'message' => "Đã xoá {$deleted} chiến dịch."
                . ($skipped > 0 ? " Bỏ qua {$skipped} chiến dịch đang gửi (huỷ gửi trước khi xoá)." : ''),
        ]);
    }

    /**
     * @param Collection<int, MailCampaign> $campaigns
     */
    private function cancelCampaigns(Collection $campaigns): string
    {
        $cancelled = MailCampaign::whereKey($campaigns->modelKeys())
            ->whereIn('status', MailCampaign::ACTIVE_STATUSES)
            ->update(['status' => MailCampaign::STATUS_CANCELLED, 'completed_at' => now()]);

        return "Đã huỷ gửi {$cancelled} chiến dịch. Email đã gửi trước đó không bị thu hồi.";
    }

    /**
     * @param Collection<int, MailCampaign> $campaigns
     */
    private function retryFailedRecipients(Collection $campaigns): string
    {
        $retried = 0;

        foreach ($campaigns->whereIn('status', ['completed', 'failed']) as $campaign) {
            DB::transaction(function () use ($campaign, &$retried) {
                $failedLogs = Mail::where('campaign_id', $campaign->id)
                    ->where('status', array_search('failed', Mail::STATUS_MAP, true))
                    ->lockForUpdate()
                    ->get(['id', 'to', 'customer_id', 'service_id']);
                if ($failedLogs->isEmpty()) {
                    return;
                }

                Mail::whereKey($failedLogs->modelKeys())->delete();
                $campaign->forceFill([
                    'failed_count' => max(0, $campaign->failed_count - $failedLogs->count()),
                    'status'       => 'sending',
                    'completed_at' => null,
                ])->save();

                foreach ($failedLogs as $log) {
                    SendMailCampaignRecipient::dispatch($campaign->id, $log->customer_id, $log->to, $log->service_id)->afterCommit();
                }
                $retried += $failedLogs->count();
            });
        }

        return $retried > 0
            ? "Đã đưa {$retried} email lỗi vào hàng đợi gửi lại."
            : 'Không có email lỗi nào để gửi lại (chỉ gửi lại chiến dịch đã kết thúc).';
    }
}