<?php

namespace App\Services\Sms;

use App\Contracts\Sms\SmsProviderInterface;
use App\Models\ContactGroup;
use App\Models\SmsCampaign;
use App\Models\SmsDelivery;
use App\Models\User;
use Carbon\CarbonInterface;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Log;

class SmsCampaignSender
{
    public function __construct(private readonly SmsProviderInterface $provider) {}

    /**
     * @param  array<int, array<string, mixed>>  $recipients
     * @param  array<int, int|string>  $selectedContactIds
     * @param  array<int, int|string>  $selectedGroupIds
     */
    public function send(
        User $user,
        string $message,
        array $recipients,
        array $selectedContactIds = [],
        array $selectedGroupIds = [],
    ): SmsCampaign {
        $campaign = $this->createCampaign($user, $message, $recipients, $selectedContactIds, $selectedGroupIds, 'sending');

        return $this->sendExistingCampaign($campaign, $recipients);
    }

    /**
     * @param  array<int, array<string, mixed>>  $recipients
     * @param  array<int, int|string>  $selectedContactIds
     * @param  array<int, int|string>  $selectedGroupIds
     */
    public function schedule(
        User $user,
        string $message,
        array $recipients,
        array $selectedContactIds,
        array $selectedGroupIds,
        CarbonInterface $scheduledAt,
    ): SmsCampaign {
        return $this->createCampaign($user, $message, $recipients, $selectedContactIds, $selectedGroupIds, 'scheduled', $scheduledAt);
    }

    public function sendScheduled(SmsCampaign $campaign): ?SmsCampaign
    {
        $campaign = DB::transaction(function () use ($campaign): ?SmsCampaign {
            $fresh = SmsCampaign::query()
                ->whereKey($campaign->id)
                ->lockForUpdate()
                ->first();

            if (! $fresh || $fresh->status !== 'scheduled') {
                return null;
            }

            $fresh->update(['status' => 'sending']);

            Log::info('SMS campaign status changed from scheduled to sending.', [
                'sms_campaign_id' => $fresh->id,
                'scheduled_at' => $fresh->scheduled_at?->toIso8601String(),
            ]);

            return $fresh->fresh(['deliveries', 'user']);
        });

        if ($campaign === null) {
            return null;
        }

        return $this->sendExistingCampaign($campaign, $this->recipientsFromDeliveries($campaign));
    }

    /**
     * @param  array<int, array<string, mixed>>  $recipients
     * @param  array<int, int|string>  $selectedContactIds
     * @param  array<int, int|string>  $selectedGroupIds
     */
    private function createCampaign(
        User $user,
        string $message,
        array $recipients,
        array $selectedContactIds,
        array $selectedGroupIds,
        string $status,
        ?CarbonInterface $scheduledAt = null,
    ): SmsCampaign {
        $selectedContactIds = $this->cleanIds($selectedContactIds);
        $selectedGroupIds = $this->cleanIds($selectedGroupIds);
        $selectedGroupNames = ContactGroup::query()
            ->whereKey($selectedGroupIds)
            ->orderBy('name')
            ->pluck('name')
            ->values()
            ->all();

        return $this->createResolvedCampaign(
            $user,
            $message,
            $recipients,
            $selectedContactIds,
            $selectedGroupIds,
            $selectedGroupNames,
            $status,
            $scheduledAt,
        );
    }

    /**
     * @param  array<int, array<string, mixed>>  $recipients
     * @param  array<int, int>  $selectedContactIds
     * @param  array<int, int>  $selectedGroupIds
     * @param  array<int, string>  $selectedGroupNames
     */
    private function createResolvedCampaign(
        User $user,
        string $message,
        array $recipients,
        array $selectedContactIds,
        array $selectedGroupIds,
        array $selectedGroupNames,
        string $status,
        ?CarbonInterface $scheduledAt,
    ): SmsCampaign {
        return DB::transaction(function () use ($user, $message, $recipients, $selectedContactIds, $selectedGroupIds, $selectedGroupNames, $status, $scheduledAt): SmsCampaign {
            $attributes = [
                'user_id' => $user->id,
                'provider' => (string) config('relais_sms.default_settings.active_sms_provider', 'ovh'),
                'status' => $status,
                'message' => $message,
                'recipients_count' => count($recipients),
                'selected_contact_ids' => $selectedContactIds,
                'selected_group_ids' => $selectedGroupIds,
                'selected_group_names' => $selectedGroupNames,
            ];

            if ($scheduledAt !== null) {
                $attributes['scheduled_at'] = $scheduledAt;
            }

            $campaign = SmsCampaign::query()->create($attributes);
            $campaign->update(['provider_tag' => 'relais-sms-campaign-'.$campaign->id]);

            foreach ($recipients as $recipient) {
                $campaign->deliveries()->create([
                    'contact_id' => $recipient['contact_id'] ?? null,
                    'contact_phone_number_id' => $recipient['phone_number_id'] ?? null,
                    'contact_name' => (string) $recipient['contact_name'],
                    'number' => (string) $recipient['number'],
                    'status' => 'queued',
                ]);
            }

            return $campaign;
        });
    }

    /**
     * @param  array<int, array<string, mixed>>  $recipients
     */
    private function sendExistingCampaign(SmsCampaign $campaign, array $recipients): SmsCampaign
    {
        try {
            $result = $this->provider->send($campaign, $recipients);
        } catch (SmsProviderException $exception) {
            $status = $exception->outcomeUnknown ? 'uncertain' : 'failed';
            $message = $exception->outcomeUnknown
                ? 'OVH n a pas confirme la reponse. Les SMS peuvent avoir ete envoyes. Verification automatique au prochain passage du cron ; ne pas renvoyer cette campagne.'
                : $exception->getMessage();

            DB::transaction(function () use ($campaign, $exception, $status, $message, $recipients): void {
                $campaign->deliveries()->update(['status' => $status, 'error_message' => $message]);
                $campaign->update([
                    'status' => $status,
                    'failed_count' => $exception->outcomeUnknown ? 0 : count($recipients),
                    'response_payload' => $exception->responsePayload,
                    'error_message' => $message,
                ]);
            });

            Log::warning('SMS provider request failed.', [
                'sms_campaign_id' => $campaign->id,
                'outcome_unknown' => $exception->outcomeUnknown,
                'reason' => $exception->getMessage(),
            ]);

            return $campaign->fresh(['deliveries', 'user']);
        }

        $failedNumbers = array_flip($result->failedNumbers);
        $sentCount = 0;
        $failedCount = 0;

        foreach ($campaign->deliveries()->orderBy('id')->get()->values() as $index => $delivery) {
            $failed = isset($failedNumbers[$delivery->number]);

            $delivery->update([
                'status' => $failed ? 'failed' : 'sent',
                'provider_message_id' => $result->providerMessageIds[$index] ?? null,
                'provider_response' => $result->responsePayload,
                'error_message' => $failed ? 'Numero refuse par OVH.' : null,
                'sent_at' => $failed ? null : now(),
            ]);

            $failed ? $failedCount++ : $sentCount++;
        }

        $campaign->update([
            'status' => $failedCount > 0 ? ($sentCount > 0 ? 'partial' : 'failed') : 'sent',
            'sent_count' => $sentCount,
            'failed_count' => $failedCount,
            'provider_service_name' => $result->serviceName,
            'provider_job_id' => $result->providerJobId,
            'message' => (string) ($result->requestPayload['message'] ?? $campaign->message),
            'request_payload' => $result->requestPayload,
            'response_payload' => $result->responsePayload,
            'sent_at' => $sentCount > 0 ? now() : null,
        ]);

        return $campaign->fresh(['deliveries', 'user']);
    }

    /**
     * @return array<int, array<string, mixed>>
     */
    private function recipientsFromDeliveries(SmsCampaign $campaign): array
    {
        return $campaign->deliveries()
            ->orderBy('id')
            ->get()
            ->map(fn (SmsDelivery $delivery): array => [
                'contact_id' => $delivery->contact_id,
                'phone_number_id' => $delivery->contact_phone_number_id,
                'contact_name' => $delivery->contact_name,
                'number' => $delivery->number,
            ])
            ->values()
            ->all();
    }

    /**
     * @param  array<int, int|string>  $ids
     * @return array<int, int>
     */
    private function cleanIds(array $ids): array
    {
        return collect($ids)
            ->map(fn (int|string $id): int => (int) $id)
            ->filter(fn (int $id): bool => $id > 0)
            ->unique()
            ->values()
            ->all();
    }
}