<?php

declare(strict_types=1);

namespace Apoloz\AlfaBank\Traits;

use Apoloz\AlfaBank\Contracts\SignerInterface;
use Apoloz\AlfaBank\Data\NominalAccounts\Payouts\DigestSignatureData;
use Spatie\LaravelData\DataCollection;

trait SignableData
{
    public function sign(SignerInterface $signer): self
    {
        // 1. Create a clone to represent the data-to-be-signed (without existing signatures)
        $clone = clone $this;

        // We explicitly set digestSignatures to null or empty for the signature calculation
        // assuming the bank expects the "business payload" only.
        // If the bank expects the field "digestSignatures": [] to be present in signed string,
        // we should initialize it as empty collection.
        // Based on common practices, we exclude it or keep it null.
        // Let's assume we exclude it (set to null if the property is nullable).
        $clone->digestSignatures = null;

        // 2. Serialize to JSON
        // We use JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES to match typical API expectations
        $jsonToSign = $clone->toJson(JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);

        // 3. Sign
        $signature = $signer->sign($jsonToSign);

        // 4. Attach signature to the original object
        if ($this->digestSignatures === null) {
            $this->digestSignatures = new DataCollection(DigestSignatureData::class, []);
        }

        // We can't push to DataCollection directly if it's not array-access compatible in all versions,
        // but Spatie DataCollection is usually iterable.
        // Safest way is to reconstruct it.
        $current = array_values($this->digestSignatures->toCollection()->all());
        $current[] = new DigestSignatureData($signature, 'cms');

        $this->digestSignatures = new DataCollection(DigestSignatureData::class, $current);

        return $this;
    }
}