<?php

declare(strict_types=1);

namespace Mironsoft\Loyalty\Console\Command;

use Mironsoft\Loyalty\Api\Data\PointsLedgerInterface;
use Mironsoft\Loyalty\Api\Data\PointsLedgerInterfaceFactory;
use Mironsoft\Loyalty\Api\PointsLedgerRepositoryInterface;
use Mironsoft\Loyalty\Model\ResourceModel\PointsLedger\Collection;
use Mironsoft\Loyalty\Model\ResourceModel\PointsLedger\CollectionFactory;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;

/**
 * Recalculates and audits customer points balances from the append-only ledger.
 */
class RecalculatePointsCommand extends Command
{
    private const OPTION_CUSTOMER_ID = 'customer-id';
    private const OPTION_DRY_RUN = 'dry-run';

    /**
     * @param CollectionFactory $ledgerCollectionFactory Factory for the ledger entry collection.
     * @param PointsLedgerRepositoryInterface $pointsLedgerRepository Persists correction entries.
     * @param PointsLedgerInterfaceFactory $pointsLedgerFactory Creates new, unsaved ledger entries.
     * @param string|null $name Optional command name override, forwarded to the parent constructor.
     */
    public function __construct(
        private readonly CollectionFactory $ledgerCollectionFactory,
        private readonly PointsLedgerRepositoryInterface $pointsLedgerRepository,
        private readonly PointsLedgerInterfaceFactory $pointsLedgerFactory,
        ?string $name = null
    ) {
        parent::__construct($name);
    }

    /**
     * Declares the command name, description, and CLI options.
     *
     * @return void
     */
    protected function configure(): void
    {
        $this->setName('mironsoft:loyalty:recalculate');
        $this->setDescription('Recalculates and audits customer points balances from the ledger.');
        $this->addOption(
            self::OPTION_CUSTOMER_ID,
            null,
            InputOption::VALUE_OPTIONAL,
            'Limit the recalculation to a single customer ID.'
        );
        $this->addOption(
            self::OPTION_DRY_RUN,
            null,
            InputOption::VALUE_NONE,
            'Only report discrepancies without writing adjustment entries.'
        );
        parent::configure();
    }

    /**
     * Walks the ledger chronologically per customer, compares the running sum against
     * the stored balance_after, and writes an "adjust" entry on drift unless dry-run.
     *
     * @param InputInterface $input CLI input, provides the command options.
     * @param OutputInterface $output CLI output, used to report progress and drift.
     * @return int
     */
    protected function execute(InputInterface $input, OutputInterface $output): int
    {
        $customerIdOption = $input->getOption(self::OPTION_CUSTOMER_ID);
        $dryRun = (bool) $input->getOption(self::OPTION_DRY_RUN);

        $collection = $this->ledgerCollectionFactory->create();
        if ($customerIdOption !== null) {
            $collection->addCustomerFilter((int) $customerIdOption);
        }
        $collection->setOrder('customer_id', Collection::SORT_ORDER_ASC);
        $collection->addOrder('created_at', Collection::SORT_ORDER_ASC);

        $runningBalance = [];
        $correctedEntries = 0;

        /** @var PointsLedgerInterface $entry */
        foreach ($collection as $entry) {
            $customerId = $entry->getCustomerId();
            $expectedBalance = ($runningBalance[$customerId] ?? 0) + $entry->getPoints();
            $runningBalance[$customerId] = $expectedBalance;

            if ($expectedBalance === $entry->getBalanceAfter()) {
                continue;
            }

            $output->writeln(sprintf(
                'Drift detected for customer #%d: ledger says %d, recalculated %d.',
                $customerId,
                $entry->getBalanceAfter(),
                $expectedBalance
            ));

            if ($dryRun) {
                continue;
            }

            $adjustment = $this->pointsLedgerFactory->create();
            $adjustment->setCustomerId($customerId);
            $adjustment->setType(PointsLedgerInterface::TYPE_ADJUST);
            $adjustment->setPoints($expectedBalance - $entry->getBalanceAfter());
            $adjustment->setBalanceAfter($expectedBalance);
            $this->pointsLedgerRepository->save($adjustment);

            $runningBalance[$customerId] = $expectedBalance;
            $correctedEntries++;
        }

        $output->writeln(sprintf('Recalculation finished, %d correction(s) written.', $correctedEntries));

        return Command::SUCCESS;
    }
}

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Mironsoft\Loyalty\Api\Data\PointsLedgerInterface"
                type="Mironsoft\Loyalty\Model\PointsLedger"/>
    <preference for="Mironsoft\Loyalty\Api\PointsLedgerRepositoryInterface"
                type="Mironsoft\Loyalty\Model\PointsLedgerRepository"/>
    <type name="Magento\Framework\Console\CommandListInterface">
        <arguments>
            <argument name="commands" xsi:type="array">
                <item name="mironsoft_loyalty_recalculate" xsi:type="object">
                    Mironsoft\Loyalty\Console\Command\RecalculatePointsCommand
                </item>
            </argument>
        </arguments>
    </type>
</config>