vanderlee/Comprehend

<?php

namespace Vanderlee\Comprehend\Parser\Output;

/**
 * @author Martijn
 */
trait ResultTrait
{
    /**
     * List of result names to assign the matched text to.
     *
     * @var callable[]
     */
    private $resultCallbacks = [];

    private function resolveResultCallbacks(&$results, $text)
    {
        foreach ($this->resultCallbacks as $callback) {
            $callback($results, $text);
        }
    }

    /**
     * After parsing, assign the matched input of this parser to the named result.
     * Only assign if successfully matched entire parent up to root.
     *
     * @param string|int $key
     * @param null|callable|string $value
     *
     * @return $this
     */
    public function setResult($key = null, $value = null)
    {
        $this->resultCallbacks[] = function (&$results, $text) use (&$key, &$value) {
            if (is_callable($value)) {
                $text = $value($text);
            } elseif ($value !== null) {
                $text = $value;
            }

            $results[$key] = $text;
        };

        return $this;
    }

    /**
     * If result exists, concatenate the matched text as a string, otherwise
     * create it. If result is an array, concat to the last entry.
     *
     * @param null|string $key
     * @param null|callable|string $value
     *
     * @return $this
     */
    public function concatResult($key = null, $value = null)
    {
        $this->resultCallbacks[] = function (&$results, $text) use (&$key, &$value) {
            if (is_callable($value)) {
                $text = $value($text);
            } elseif ($value !== null) {
                $text = $value;
            }

            if (!isset($results[$key])) {
                $results[$key] = (string)$text;
            } elseif (is_array($results[$key])) {
                $results[$key][] = array_pop($results[$key]) . $text;
            } else {
                $results[$key] .= $text;
            }
        };

        return $this;
    }

    /**
     * Turn the result into an array and start a new entry.
     *
     * @param null|string $key
     * @param null|callable|string $value
     *
     * @return $this
     */
    public function pushResult($key = null, $value = null)
    {
        $this->resultCallbacks[] = function (&$results, $text) use (&$key, &$value) {
            if (is_callable($value)) {
                $text = $value($text);
            } elseif ($value !== null) {
                $text = $value;
            }

            if (!isset($results[$key])) {
                $results[$key] = [$text];
            } elseif (is_array($results[$key])) {
                $results[$key][] = $text;
            } else {
                $results[$key] = [$results[$key], $text];
            }
        };

        return $this;
    }
}