<?php

declare(strict_types=1);

/*
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */

namespace TYPO3\CMS\Form\ViewHelpers;

use TYPO3\CMS\Form\Domain\Model\Renderable\RenderableInterface;
use TYPO3\CMS\Form\Domain\Model\Renderable\RootRenderableInterface;
use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;

/**
 * Scope: frontend
 *
 * @see https://docs.typo3.org/permalink/t3viewhelper:typo3-form-gridcolumnclassautoconfiguration
 */
final class GridColumnClassAutoConfigurationViewHelper extends AbstractViewHelper
{
    /**
     * @var bool
     */
    protected $escapeOutput = false;

    public function initializeArguments(): void
    {
        $this->registerArgument('element', RootRenderableInterface::class, 'A RootRenderableInterface instance', true);
    }

    public function render(): string
    {
        $formElement = $this->arguments['element'];

        if ($formElement instanceof RenderableInterface && !$formElement->isEnabled()) {
            return '';
        }

        $gridRowElement = $formElement->getParentRenderable();
        $gridRowChildElements = $gridRowElement->getElements();
        $gridViewPortConfiguration = $gridRowElement->getProperties()['gridColumnClassAutoConfiguration'];
        if (empty($gridViewPortConfiguration)) {
            return '';
        }
        $gridSize = (int)$gridViewPortConfiguration['gridSize'];
        $columnsToCalculate = [];
        $usedColumns = [];
        foreach ($gridRowChildElements as $childElement) {
            if ($childElement instanceof RenderableInterface && !$childElement->isEnabled()) {
                continue;
            }
            if (empty($childElement->getProperties()['gridColumnClassAutoConfiguration'])) {
                foreach ($gridViewPortConfiguration['viewPorts'] as $viewPortName => $configuration) {
                    $columnsToCalculate[$viewPortName]['elements'] = ($columnsToCalculate[$viewPortName]['elements'] ?? 0) + 1;
                }
            } else {
                $gridColumnViewPortConfiguration = $childElement->getProperties()['gridColumnClassAutoConfiguration'];
                foreach ($gridViewPortConfiguration['viewPorts'] as $viewPortName => $configuration) {
                    $configuration = $gridColumnViewPortConfiguration['viewPorts'][$viewPortName] ?? [];
                    if (
                        isset($configuration['numbersOfColumnsToUse'])
                        && (int)$configuration['numbersOfColumnsToUse'] > 0
                    ) {
                        $usedColumns[$viewPortName]['sum'] = ($usedColumns[$viewPortName]['sum'] ?? 0);
                        $usedColumns[$viewPortName]['sum'] += (int)$configuration['numbersOfColumnsToUse'];
                        if ($childElement->getIdentifier() === $formElement->getIdentifier()) {
                            $usedColumns[$viewPortName]['concreteNumbersOfColumnsToUse'] = (int)$configuration['numbersOfColumnsToUse'];
                            if ($usedColumns[$viewPortName]['concreteNumbersOfColumnsToUse'] > $gridSize) {
                                $usedColumns[$viewPortName]['concreteNumbersOfColumnsToUse'] = $gridSize;
                            }
                        }
                    } else {
                        $columnsToCalculate[$viewPortName]['elements'] = ($columnsToCalculate[$viewPortName]['elements'] ?? 0) + 1;
                    }
                }
            }
        }
        $classes = [];
        foreach ($gridViewPortConfiguration['viewPorts'] as $viewPortName => $configuration) {
            if (isset($usedColumns[$viewPortName]['concreteNumbersOfColumnsToUse'])) {
                $numbersOfColumnsToUse = $usedColumns[$viewPortName]['concreteNumbersOfColumnsToUse'];
            } else {
                $restColumnsToDivide = $gridSize - ($usedColumns[$viewPortName]['sum'] ?? 0);
                $restElements = (int)$columnsToCalculate[$viewPortName]['elements'];

                if ($restColumnsToDivide < 1) {
                    $restColumnsToDivide = $gridSize;
                }
                $numbersOfColumnsToUse = floor($restColumnsToDivide / $restElements);
            }

            $classes[] = str_replace(
                '{@numbersOfColumnsToUse}',
                (string)$numbersOfColumnsToUse,
                $configuration['classPattern']
            );
        }
        return implode(' ', $classes);
    }
}