<?php

namespace App\Services\Didit;

use App\Enums\IdentityVerificationStatusEnum;
use App\Enums\UserTypeEnum;
use App\Models\Client;
use App\Models\IdentityVerification;
use App\Models\Provider;
use App\Models\User;
use App\Services\ProviderService;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Log;

class DiditDecisionService
{
    public function __construct(
        private readonly DiditDecisionExtractor $extractor,
        private readonly ProviderService $providerService,
    ) {}

    public function handleWebhook(array $payload): ?IdentityVerification
    {
        $sessionId = data_get($payload, 'session_id');
        $status    = (string) data_get($payload, 'status');

        if (! is_string($sessionId) || $sessionId === '') {
            Log::channel('didit')->warning('Webhook sem session_id; ignorado');

            return null;
        }

        $user = $this->resolveUser($payload);

        if (! $user) {
            Log::channel('didit')->warning('Webhook sem usuario correspondente', [
                'session_id'  => $sessionId,
                'vendor_data' => data_get($payload, 'vendor_data'),
            ]);

            return null;
        }

        $decision     = (array) (data_get($payload, 'decision') ?? []);
        $verification = $this->persist($user, $sessionId, $status, $payload, $decision);

        if (! in_array($status, IdentityVerificationStatusEnum::diditTerminalStatuses(), true)) {
            return $verification;
        }

        $this->applyDecision($user, $verification, $status, $decision);

        return $verification->refresh();
    }

    //

    private function persist(
        User $user,
        string $sessionId,
        string $status,
        array $payload,
        array $decision,
    ): IdentityVerification {
        $verification = IdentityVerification::firstOrNew(['session_id' => $sessionId]);

        $attributes = [
            'user_id'      => $user->id,
            'didit_status' => $status,
            'workflow_id'  => data_get($payload, 'workflow_id') ?? $verification->workflow_id,
        ];

        if ($decision !== []) {
            $attributes = [
                ...$attributes,
                ...$this->extractor->extract($decision),
                'decision' => $this->sanitize($decision),
            ];
        }

        if (! $verification->exists) {
            $attributes['attempt']    = (int) $user->identityVerifications()->count() + 1;
            $attributes['started_at'] = now();
        }

        if (in_array($status, IdentityVerificationStatusEnum::diditTerminalStatuses(), true)) {
            $attributes['completed_at'] = now();
        }

        $verification->fill($attributes)->save();

        return $verification;
    }

    private function applyDecision(
        User $user,
        IdentityVerification $verification,
        string $status,
        array $decision,
    ): void {
        $profile = $this->profileFor($user);

        if (! $profile) {
            return;
        }

        if ($status === 'Approved' && $this->passesAllGates($verification, $decision)) {
            $this->approve($user, $profile, $verification);

            return;
        }

        if ($status === 'Declined') {
            $this->decline($profile);

            return;
        }

        // Approved com pendencia, In Review ou Abandoned: decisao humana.
        $this->sendToReview($profile);
    }

    private function passesAllGates(IdentityVerification $verification, array $decision): bool
    {
        $required = ['id_verifications', 'liveness_checks', 'face_matches'];

        foreach ($required as $key) {
            $items = $this->extractor->items($decision, $key);

            if ($items === []) {
                $this->logGate($verification, "feature ausente: {$key}");

                return false;
            }

            foreach ($items as $item) {
                if (data_get($item, 'status') !== 'Approved') {
                    $this->logGate($verification, "feature reprovada: {$key}");

                    return false;
                }
            }
        }

        $minLiveness  = (float) config('services.didit.liveness_min_score');
        $minFaceMatch = (float) config('services.didit.face_match_min_score');

        if ($verification->liveness_score === null || $verification->liveness_score < $minLiveness) {
            $this->logGate($verification, 'liveness abaixo do minimo');

            return false;
        }

        if ($verification->face_match_score === null || $verification->face_match_score < $minFaceMatch) {
            $this->logGate($verification, 'face match abaixo do minimo');

            return false;
        }

        if ($this->extractor->actionableWarnings($decision) !== []) {
            $this->logGate($verification, 'warnings acionaveis presentes');

            return false;
        }

        return true;
    }

    private function approve(User $user, Model $profile, IdentityVerification $verification): void
    {
        DB::transaction(function () use ($profile, $verification) {
            $profile->forceFill([
                'identity_verification_status' => IdentityVerificationStatusEnum::APPROVED->value,
                'identity_verified_at'         => now(),
            ]);

            if ($profile instanceof Provider) {
                $profile->document_verified = true;
            }

            if ($profile->profile_media_id) {
                $profile->selfie_verified = true;
            }

            $profile->save();

            $verification->forceFill(['completed_at' => now()])->save();
        });

        if ($profile instanceof Provider) {
            $this->providerService->approve($profile->id);
        }

        Log::channel('didit')->info('Verificacao aprovada automaticamente', [
            'user_id'    => $user->id,
            'session_id' => $verification->session_id,
        ]);
    }

    private function decline(Model $profile): void
    {
        $attempts = (int) $profile->identity_verification_attempts + 1;
        $max      = (int) config('services.didit.max_attempts', 3);

        $profile->forceFill([
            'identity_verification_attempts' => $attempts,
            'identity_verification_status'   => $attempts >= $max
                ? IdentityVerificationStatusEnum::IN_REVIEW->value
                : IdentityVerificationStatusEnum::DECLINED->value,
        ])->save();
    }

    private function sendToReview(Model $profile): void
    {
        $profile->forceFill([
            'identity_verification_status' => IdentityVerificationStatusEnum::IN_REVIEW->value,
        ])->save();
    }

    private function resolveUser(array $payload): ?User
    {
        $vendorData = data_get($payload, 'vendor_data');

        if (is_numeric($vendorData)) {
            return User::find((int) $vendorData);
        }

        $sessionId = data_get($payload, 'session_id');

        return IdentityVerification::where('session_id', $sessionId)->first()?->user;
    }

    private function profileFor(User $user): Provider|Client|null
    {
        return $user->type === UserTypeEnum::PROVIDER
            ? $user->provider
            : $user->client;
    }

    private function sanitize(array $decision): array
    {
        array_walk_recursive($decision, static function (&$value) {
            if (is_string($value) && str_starts_with($value, 'http')) {
                $value = explode('?', $value)[0];
            }
        });

        return $decision;
    }

    private function logGate(IdentityVerification $verification, string $reason): void
    {
        Log::channel('didit')->info('Aprovacao automatica barrada', [
            'session_id' => $verification->session_id,
            'motivo'     => $reason,
        ]);
    }
}