the-kbA-team/markdown-table

<?php

namespace kbATeam\MarkdownTable;

use RuntimeException;

/**
 * Class kbATeam\MarkdownTable\Column
 *
 * Manages column attributes of a Markdown table.
 *
 * @category library
 * @package  kbATeam\MarkdownTable
 * @license  MIT
 * @author   gregor-j
 */
class Column
{
    /**
     * @const int column alignment left
     */
    public const ALIGN_LEFT = 1;

    /**
     * @const int column alignment right
     */
    public const ALIGN_RIGHT = 2;

    /**
     * @const int column alignment center
     */
    public const ALIGN_CENTER = 3;

    /**
     * @var string column title
     */
    private $title;

    /**
     * @var int column alignment
     */
    private $alignment;

    /**
     * @var int max length of column
     */
    private $length;

    /**
     * @var string PCRE regex to validate alignment constants
     */
    private $regex_alignment;

    /**
     * Column constructor.
     * @param string $title The columns' title
     * @param int|null $alignment Optional column alignment. Default: ALIGN_LEFT
     */
    public function __construct($title, $alignment = null)
    {
        $this->regex_alignment = '~^('.self::ALIGN_LEFT.'|'.self::ALIGN_RIGHT.'|'.self::ALIGN_CENTER.')$~';
        $this->length = 3;
        $this->setTitle($title);
        if (null === $alignment) {
            $alignment = self::ALIGN_LEFT;
        }
        $this->setAlignment($alignment);
    }

    /**
     * Set the columns' title.
     * @param string $title The columns' title.
     * @throws \RuntimeException in case the title is no string or too short.
     */
    public function setTitle($title)
    {
        if (!is_string($title)) {
            throw new RuntimeException('Column title is no string.');
        }

        $this->title = filter_var(
            $title,
            FILTER_SANITIZE_SPECIAL_CHARS,
            FILTER_FLAG_STRIP_BACKTICK | FILTER_FLAG_STRIP_LOW | FILTER_FLAG_STRIP_HIGH
        );

        if (false === $this->title || $this->title === '') {
            $this->title = null;
            throw new RuntimeException('Column title is too short.');
        }
        $this->setMaxLength(mb_strlen($this->title));
    }

    /**
     * Set the columns' alignment.
     * @param int $alignment The columns' alignment.
     * @throws \RuntimeException in case the given alignment is no alignment constant.
     */
    public function setAlignment($alignment)
    {
        $this->alignment = (int)filter_var(
            $alignment,
            FILTER_VALIDATE_REGEXP,
            [
                'options' => [
                    'regexp' => $this->regex_alignment
                ]
            ]
        );

        if (0 === $this->alignment) {
            $this->alignment = null;
            throw new RuntimeException('Invalid alignment constant.');
        }
    }

    /**
     * Sets the columns' maximum length.
     * @param int $length The columns' maximum length.
     * @throws \RuntimeException in case the given length is no positive integer.
     */
    public function setMaxLength($length)
    {
        if (!is_int($length) || $length < 0) {
            throw new RuntimeException('Column length needs to be a positive integer.');
        }
        
        $this->length = max($this->length, $length);
    }

    /**
     * Reset a columns maximum length to a minimum of three or the title length.
     */
    public function resetMaxLength()
    {
        $this->length = max(3, mb_strlen($this->title));
    }

    /**
     * Create a column cell string using the given content.
     * @param string $content The cells' content.
     * @return string The cells content with spaces to fill the whole cell length.
     * @throws \RuntimeException in case the given content is longer than the maximum length of this cell.
     */
    public function createCell($content): string
    {
        $diff = $this->length - mb_strlen($content);

        if ($diff < 0) {
            throw new RuntimeException('Content length too long.');
        }

        switch ($this->alignment) {
            case self::ALIGN_RIGHT:
                $result = sprintf('%s%s', str_repeat(' ', $diff), $content);
                break;
            case self::ALIGN_CENTER:
                $diff_left = floor($diff / 2);
                $result = sprintf(
                    '%s%s%s',
                    str_repeat(' ', $diff_left),
                    $content,
                    str_repeat(' ', $diff - $diff_left)
                );
                break;
            default:
                $result = sprintf('%s%s', $content, str_repeat(' ', $diff));
                break;
        }

        unset($diff, $diff_left);
        return $result;
    }

    /**
     * Creates the column header string.
     * @return string The column header string.
     */
    public function createHeader(): string
    {
        return $this->createCell($this->title);
    }

    /**
     * Creates the column header separator string.
     * @return string The column header separator string.
     */
    public function createHeaderSeparator(): string
    {
        switch ($this->alignment) {
            case self::ALIGN_RIGHT:
                $result = sprintf(
                    '%s:',
                    str_repeat('-', $this->length-1)
                );
                break;
            case self::ALIGN_CENTER:
                $result = sprintf(
                    ':%s:',
                    str_repeat('-', $this->length-2)
                );
                break;
            default:
                $result = str_repeat('-', $this->length);
                break;
        }
        return $result;
    }
}