<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Config\Definition\Dumper;

use Symfony\Component\Config\Definition\ArrayNode;
use Symfony\Component\Config\Definition\BaseNode;
use Symfony\Component\Config\Definition\ConfigurationInterface;
use Symfony\Component\Config\Definition\EnumNode;
use Symfony\Component\Config\Definition\NodeInterface;
use Symfony\Component\Config\Definition\PrototypedArrayNode;
use Symfony\Component\Config\Definition\ScalarNode;
use Symfony\Component\Yaml\Inline;

/**
 * Dumps a Yaml reference configuration for the given configuration/node instance.
 *
 * @author Kevin Bond <kevinbond@gmail.com>
 */
class YamlReferenceDumper
{
    private ?string $reference = null;

    /**
     * @return string
     */
    public function dump(ConfigurationInterface $configuration)
    {
        return $this->dumpNode($configuration->getConfigTreeBuilder()->buildTree());
    }

    /**
     * @return string
     */
    public function dumpAtPath(ConfigurationInterface $configuration, string $path)
    {
        $rootNode = $node = $configuration->getConfigTreeBuilder()->buildTree();

        foreach (explode('.', $path) as $step) {
            if (!$node instanceof ArrayNode) {
                throw new \UnexpectedValueException(sprintf('Unable to find node at path "%s.%s".', $rootNode->getName(), $path));
            }

            /** @var NodeInterface[] $children */
            $children = $node instanceof PrototypedArrayNode ? $this->getPrototypeChildren($node) : $node->getChildren();

            foreach ($children as $child) {
                if ($child->getName() === $step) {
                    $node = $child;

                    continue 2;
                }
            }

            throw new \UnexpectedValueException(sprintf('Unable to find node at path "%s.%s".', $rootNode->getName(), $path));
        }

        return $this->dumpNode($node);
    }

    /**
     * @return string
     */
    public function dumpNode(NodeInterface $node)
    {
        $this->reference = '';
        $this->writeNode($node);
        $ref = $this->reference;
        $this->reference = null;

        return $ref;
    }

    private function writeNode(NodeInterface $node, ?NodeInterface $parentNode = null, int $depth = 0, bool $prototypedArray = false): void
    {
        $comments = [];
        $default = '';
        $defaultArray = null;
        $children = null;
        $example = null;
        if ($node instanceof BaseNode) {
            $example = $node->getExample();
        }

        // defaults
        if ($node instanceof ArrayNode) {
            $children = $node->getChildren();

            if ($node instanceof PrototypedArrayNode) {
                $children = $this->getPrototypeChildren($node);
            }

            if (!$children && !($node->hasDefaultValue() && \count($defaultArray = $node->getDefaultValue()))) {
                $default = '[]';
            }
        } elseif ($node instanceof EnumNode) {
            $comments[] = 'One of '.$node->getPermissibleValues('; ');
            $default = $node->hasDefaultValue() ? Inline::dump($node->getDefaultValue()) : '~';
        } else {
            $default = '~';

            if ($node->hasDefaultValue()) {
                $default = $node->getDefaultValue();

                if (\is_array($default)) {
                    if (\count($defaultArray = $node->getDefaultValue())) {
                        $default = '';
                    } elseif (!\is_array($example)) {
                        $default = '[]';
                    }
                } else {
                    $default = Inline::dump($default);
                }
            }
        }

        // required?
        if ($node->isRequired()) {
            $comments[] = 'Required';
        }

        // deprecated?
        if ($node instanceof BaseNode && $node->isDeprecated()) {
            $deprecation = $node->getDeprecation($node->getName(), $parentNode ? $parentNode->getPath() : $node->getPath());
            $comments[] = sprintf('Deprecated (%s)', ($deprecation['package'] || $deprecation['version'] ? "Since {$deprecation['package']} {$deprecation['version']}: " : '').$deprecation['message']);
        }

        // example
        if ($example && !\is_array($example)) {
            $comments[] = 'Example: '.Inline::dump($example);
        }

        $default = '' != (string) $default ? ' '.$default : '';
        $comments = \count($comments) ? '# '.implode(', ', $comments) : '';

        $key = $prototypedArray ? '-' : $node->getName().':';
        $text = rtrim(sprintf('%-21s%s %s', $key, $default, $comments), ' ');

        if ($node instanceof BaseNode && $info = $node->getInfo()) {
            $this->writeLine('');
            // indenting multi-line info
            $info = str_replace("\n", sprintf("\n%".($depth * 4).'s# ', ' '), $info);
            $this->writeLine('# '.$info, $depth * 4);
        }

        $this->writeLine($text, $depth * 4);

        // output defaults
        if ($defaultArray) {
            $this->writeLine('');

            $message = \count($defaultArray) > 1 ? 'Defaults' : 'Default';

            $this->writeLine('# '.$message.':', $depth * 4 + 4);

            $this->writeArray($defaultArray, $depth + 1);
        }

        if (\is_array($example)) {
            $this->writeLine('');

            $message = \count($example) > 1 ? 'Examples' : 'Example';

            $this->writeLine('# '.$message.':', $depth * 4 + 4);

            $this->writeArray(array_map(Inline::dump(...), $example), $depth + 1, true);
        }

        if ($children) {
            foreach ($children as $childNode) {
                $this->writeNode($childNode, $node, $depth + 1, $node instanceof PrototypedArrayNode && !$node->getKeyAttribute());
            }
        }
    }

    /**
     * Outputs a single config reference line.
     */
    private function writeLine(string $text, int $indent = 0): void
    {
        $indent = \strlen($text) + $indent;
        $format = '%'.$indent.'s';

        $this->reference .= sprintf($format, $text)."\n";
    }

    private function writeArray(array $array, int $depth, bool $asComment = false): void
    {
        $isIndexed = array_is_list($array);

        foreach ($array as $key => $value) {
            if (\is_array($value)) {
                $val = '';
            } else {
                $val = $value;
            }

            $prefix = $asComment ? '# ' : '';

            if ($isIndexed) {
                $this->writeLine($prefix.'- '.$val, $depth * 4);
            } else {
                $this->writeLine(sprintf('%s%-20s %s', $prefix, $key.':', $val), $depth * 4);
            }

            if (\is_array($value)) {
                $this->writeArray($value, $depth + 1, $asComment);
            }
        }
    }

    private function getPrototypeChildren(PrototypedArrayNode $node): array
    {
        $prototype = $node->getPrototype();
        $key = $node->getKeyAttribute();

        // Do not expand prototype if it isn't an array node nor uses attribute as key
        if (!$key && !$prototype instanceof ArrayNode) {
            return $node->getChildren();
        }

        if ($prototype instanceof ArrayNode) {
            $keyNode = new ArrayNode($key, $node);
            $children = $prototype->getChildren();

            if ($prototype instanceof PrototypedArrayNode && $prototype->getKeyAttribute()) {
                $children = $this->getPrototypeChildren($prototype);
            }

            // add children
            foreach ($children as $childNode) {
                $keyNode->addChild($childNode);
            }
        } else {
            $keyNode = new ScalarNode($key, $node);
        }

        $info = 'Prototype';
        if (null !== $prototype->getInfo()) {
            $info .= ': '.$prototype->getInfo();
        }
        $keyNode->setInfo($info);

        return [$key => $keyNode];
    }
}
