Axiom\Rivescript\Cortex\Node

Complexity

Total Complexity

59

Size/Duplication

Total Lines	331
Duplicated Lines	0 %

Importance

Changes	2
Bugs	0	Features	0

15 Methods

Rating	Name	Duplication	Size	Complexity
A	isEmpty()	0	3	1
A	determineCommand()	0	9	2
A	isComment()	0	3	1
A	command()	0	3	1
A	determineEmpty()	0	3	1
A	source()	0	3	1
A	value()	0	3	1
D	checkSyntax()	0	107	39
A	number()	0	3	1
A	__construct()	0	9	1
A	matchesPattern()	0	5	1
A	determineValue()	0	3	1
A	setAllowUtf8()	0	3	1
A	determineComment()	0	14	6
A	isInterrupted()	0	3	1

<?php
/*
 * This file is part of Rivescript-php
 *
 * (c) Shea Lewis <shea.lewis89@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Axiom\Rivescript\Cortex;

/**
 * Node class
 *
 * The Node class stores information about a parsed
 * line from the script.
 *
 * PHP version 7.4 and higher.
 *
 * @category Core
 * @package  Cortext
 * @author   Shea Lewis <shea.lewis89@gmail.com>
 * @license  https://opensource.org/licenses/MIT MIT
 * @link     https://github.com/axiom-labs/rivescript-php
 * @since    0.3.0
 */
class Node
{
    /**
     * The source string for the node.
     *
     * @var string
     */
    protected string $source = '';

    /**
     * The line number of the node source.
     *
     * @var int
     */
    protected int $number = 0;

    /**
     * The command symbol.
     *
     * @var string
     */
    protected string $command = '';

    /**
     * The source without the command symbol.
     *
     * @var string
     */
    protected string $value = '';

    /**
     * Is this line part of a docblock.
     *
     * @var bool
     */
    protected bool $isInterrupted = false;

    /**
     * Is this node a comment.
     *
     * @var bool
     */
    protected bool $isComment = false;


    /**
     * Is this an empty line.
     *
     * @var bool
     */
    public bool $isEmpty = false;

    /**
     * Is UTF8 modes enabled.
     *
     * @var bool
     */
    protected bool $allowUtf8 = false;

    /**
     * Create a new Source instance.
     *
     * @param string $source The source line.
     * @param int    $number The line number in the script.
     */
    public function __construct(string $source, int $number)
    {
        $this->source = remove_whitespace($source);
        $this->number = $number;

        $this->determineEmpty();
        $this->determineComment();
        $this->determineCommand();
        $this->determineValue();
    }

    /**
     * Returns the node's command trigger.
     *
     * @return string
     */
    public function command(): string
    {
        return $this->command;
    }

    /**
     * Returns the node's value.
     *
     * @return string
     */
    public function value(): string
    {
        return $this->value;
    }

    /**
     * Returns the node's source.
     *
     * @return string
     */
    public function source(): string
    {
        return $this->source;
    }

    /**
     * Returns the node's line number.
     *
     * @return int
     */
    public function number(): int
    {
        return $this->number;
    }

    public function isEmpty(): bool
    {
        return $this->isEmpty;
    }

    /**
     * Returns true if node is a comment.
     *
     * @return bool
     */
    public function isComment(): bool
    {
        return $this->isComment;
    }

    /**
     * Returns true is node has been interrupted.
     *
     * @return bool
     */
    public function isInterrupted(): bool
    {
        return $this->isInterrupted;
    }

    /**
     * Determine the command type of the node.
     *
     * @return void
     */
    protected function determineCommand(): void
    {
        if ($this->source === '') {
            $this->isInterrupted = true;

            return;
        }

        $this->command = mb_substr($this->source, 0, 1);
    }

    protected function determineEmpty(): void
    {
        $this->isEmpty = empty(trim($this->source()));
    }

    /**
     * Determine if the current node source is a comment.
     *
     * @return void
     */
    protected function determineComment(): void
    {
        if (starts_with($this->source, '//')) {
            $this->isInterrupted = true;
        } elseif (starts_with($this->source, '#')) {
            log_warning('Using the # symbol for comments is deprecated');
            $this->isInterrupted = true;
        } elseif (starts_with($this->source, '/*')) {
            if (ends_with($this->source, '*/')) {
                return;
            }
            $this->isComment = true;
        } elseif (ends_with($this->source, '*/')) {
            $this->isComment = false;
        }
    }

    /**
     * Determine the value of the node.
     *
     * @return void
     */
    protected function determineValue(): void
    {
        $this->value = trim(mb_substr($this->source, 1));
    }

    /**
     * Enable the UTF8 mode.
     *
     * @param bool $allowUtf8 True of false.
     */
    public function setAllowUtf8(bool $allowUtf8): void
    {
        $this->allowUtf8 = $allowUtf8;
    }

    /**
     * Check the syntax
     *
     * @return string
     */
    public function checkSyntax(): string
    {
        if (starts_with($this->source, '!')) {
            # ! Definition
            #   - Must be formatted like this:
            #     ! type name = value
            #     OR
            #     ! type = value
            #   - Type options are NOT enforceable, for future compatibility; if RiveScript
            #     encounters a new type that it can't handle, it can safely warn and skip it.
            if ($this->matchesPattern("/^.+(?:\s+.+|)\s*=\s*.+?$/", $this->source) === false) {
                return "Invalid format for !Definition line: must be '! type name = value' OR '! type = value'";
            }
        } elseif (starts_with($this->source, '>')) {
            # > Label
            #   - The "begin" label must have only one argument ("begin")
            #   - "topic" labels must be lowercase but can inherit other topics ([A-Za-z0-9_\s])
            #   - "object" labels follow the same rules as "topic" labels, but don't need be lowercase
            if ($this->matchesPattern("/^begin/", $this->value) === true
                && $this->matchesPattern("/^begin$/", $this->value) === false) {
                return "The 'begin' label takes no additional arguments, should be verbatim '> begin'";
            } elseif ($this->matchesPattern("/^topic/", $this->value) === true
                && $this->matchesPattern("/[^a-z0-9_\-\s]/", $this->value) === true) {
                return "Topics should be lowercased and contain only numbers and letters!";
            } elseif ($this->matchesPattern("/^object/", $this->value) === true
                && $this->matchesPattern("/[^a-z0-9_\-\s]/", $this->value) === true) {
                return "Objects can only contain numbers and lowercase letters!";
            }
        } elseif (starts_with($this->source, '+') || starts_with($this->source, '%')
            || starts_with($this->source, '@')) {
            # + Trigger, % Previous, @ Redirect
            #   This one is strict. The triggers are to be run through Perl's regular expression
            #   engine. Therefore, it should be acceptable by the regexp engine.
            #   - Entirely lowercase
            #   - No symbols except: ( | ) [ ] * _ # @ { } < > =
            #   - All brackets should be matched

            if ($this->allowUtf8 === true) {
                if ($this->matchesPattern("/[A-Z\\.]/", $this->value) === true) {
                    return "Triggers can't contain uppercase letters, backslashes or dots in UTF-8 mode.";
                }
            } elseif ($this->matchesPattern("/[^a-z0-9(\|)\[\]*_#\@{}<>=\s]/", $this->value) === true) {
                return "Triggers may only contain lowercase letters, numbers, and these symbols: ( | ) [ ] * _ # @ { } < > =";
            }

            $parens = 0; # Open parenthesis
            $square = 0; # Open square brackets
            $curly = 0; # Open curly brackets
            $chevron = 0; # Open angled brackets
            $len = strlen($this->value);

            for ($i = 0; $i < $len; $i++) {
                $chr = $this->value[$i];

                # Count brackets.
                if ($chr === '(') {
                    $parens++;
                }
                if ($chr === ')') {
                    $parens--;
                }
                if ($chr === '[') {
                    $square++;
                }
                if ($chr === ']') {
                    $square--;
                }
                if ($chr === '{') {
                    $curly++;
                }
                if ($chr === '}') {
                    $curly--;
                }
                if ($chr === '<') {
                    $chevron++;
                }
                if ($chr === '>') {
                    $chevron--;
                }
            }

            if ($parens) {
                return "Unmatched " . ($parens > 0 ? "left" : "right") . " parenthesis bracket ()";
            }
            if ($square) {
                return "Unmatched " . ($square > 0 ? "left" : "right") . " square bracket []";
            }
            if ($curly) {
                return "Unmatched " . ($curly > 0 ? "left" : "right") . " curly bracket {}";
            }
            if ($chevron) {
                return "Unmatched " . ($chevron > 0 ? "left" : "right") . " angled bracket <>";
            }
        } elseif (starts_with($this->source, '-') || starts_with($this->source, '^')
            || starts_with($this->source, '/')) {
            # - Trigger, ^ Continue, / Comment
            # These commands take verbatim arguments, so their syntax is loose.
        } elseif (starts_with($this->source, '*') === true && $this->isComment() === false) {
            # * Condition
            #   Syntax for a conditional is as follows:
            #   * value symbol value => response
            if ($this->matchesPattern("/.+?\s(==|eq|!=|ne|<>|<|<=|>|>=)\s.+?=>.+?$/", $this->value) === false) {
                return "Invalid format for !Condition: should be like `* value symbol value => response`";
            }
        }

        return "";
    }

    /**
     * Check for patterns in a given string.
     *
     * @param string $regex  The pattern to detect.
     * @param string $string The string that could contain the pattern.
     *
     * @return bool
     */
    private function matchesPattern(string $regex = '', string $string = ''): bool
    {
        preg_match_all($regex, $string, $matches);

        return isset($matches[0][0]);
    }
}