<?php

/**
 * This file is part of the Nette Framework (https://nette.org)
 * Copyright (c) 2004 David Grudl (https://davidgrudl.com)
 */

declare(strict_types=1);

namespace Nette\Neon;

use function array_keys, count, is_array, is_int, is_object, is_string, max, range;


/**
 * Converts value to NEON format.
 * @internal
 */
final class Encoder
{
	/** @deprecated */
	public const BLOCK = true;

	public bool $blockMode = false;
	public string $indentation = "\t";


	/**
	 * Returns the NEON representation of a value.
	 */
	public function encode(mixed $val): string
	{
		$node = $this->valueToNode($val, $this->blockMode);
		return $node->toString();
	}


	public function valueToNode(mixed $val, bool $blockMode = false): Node
	{
		if ($val instanceof \DateTimeInterface) {
			return new Node\LiteralNode($val);

		} elseif ($val instanceof Entity && $val->value === Neon::Chain) {
			$node = new Node\EntityChainNode;
			foreach ($val->attributes as $entity) {
				$node->chain[] = $this->valueToNode($entity);
			}

			return $node;

		} elseif ($val instanceof Entity) {
			return new Node\EntityNode(
				$this->valueToNode($val->value),
				$this->arrayToNodes($val->attributes),
			);

		} elseif (is_object($val) || is_array($val)) {
			if ($blockMode) {
				$node = new Node\BlockArrayNode;
			} else {
				$isList = is_array($val) && (!$val || array_keys($val) === range(0, count($val) - 1));
				$node = new Node\InlineArrayNode($isList ? '[' : '{');
			}

			$node->items = $this->arrayToNodes($val, $blockMode);
			return $node;

		} elseif (is_string($val)) {
			if (preg_match('//u', $val) === false) {
				trigger_error('Invalid UTF-8 sequence in string, replaced with U+FFFD', E_USER_WARNING);
				$val = json_decode(json_encode($val, JSON_INVALID_UTF8_SUBSTITUTE));
			}
			return Lexer::requiresDelimiters($val)
				? new Node\StringNode($val, $this->indentation)
				: new Node\LiteralNode($val);

		} else {
			return new Node\LiteralNode($val);
		}
	}


	/** @return Node\ArrayItemNode[] */
	private function arrayToNodes(mixed $val, bool $blockMode = false): array
	{
		$res = [];
		$counter = 0;
		$hide = true;
		foreach ($val as $k => $v) {
			$res[] = $item = new Node\ArrayItemNode;
			$item->key = $hide && $k === $counter ? null : self::valueToNode($k);
			$item->value = self::valueToNode($v, $blockMode);
			if ($item->value instanceof Node\BlockArrayNode) {
				$item->value->indentation = $this->indentation;
			}

			if ($hide && is_int($k)) {
				$hide = $k === $counter;
				$counter = max($k + 1, $counter);
			}
		}

		return $res;
	}
}