<?php
/**
 * PHPWord
 *
 * @link        https://github.com/PHPOffice/PHPWord
 * @copyright   2014 PHPWord
 * @license     http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt LGPL
 */

namespace PhpOffice\PhpWord\Style;

use PhpOffice\PhpWord\Shared\XMLWriter;

/**
 * Tab style
 */
class Tab extends AbstractStyle
{
    /**
     * Tab Stop Type
     *
     * @var string
     */
    private $val;

    /**
     * Tab Leader Character
     *
     * @var string
     */
    private $leader;

    /**
     * Tab Stop Position
     *
     * @var int
     */
    private $position;

    /**
     * Tab Stop Type
     *
     * @var array
     * @link http://www.schemacentral.com/sc/ooxml/a-w_val-26.html Tab Stop Type
     */
    private static $possibleStopTypes = array(
        'clear', // No Tab Stop
        'left', // Left Tab Stop
        'center', // Center Tab Stop
        'right', // Right Tab Stop
        'decimal', // Decimal Tab
        'bar', // Bar Tab
        'num' // List tab
    );

    /**
     * Tab Leader Character
     *
     * @var array
     * @link http://www.schemacentral.com/sc/ooxml/a-w_leader-1.html Tab Leader Character
     */
    private static $possibleLeaders = array(
        'none', // No tab stop leader
        'dot', // Dotted leader line
        'hyphen', // Dashed tab stop leader line
        'underscore', // Solid leader line
        'heavy', // Heavy solid leader line
        'middleDot' // Middle dot leader line
    );

    /**
     * Create a new instance of Tab. Both $val and $leader
     * must conform to the values put forth in the schema. If they do not
     * they will be changed to default values.
     *
     * @param string $val Defaults to 'clear' if value is not possible.
     * @param int $position Must be an integer; otherwise defaults to 0.
     * @param string $leader Defaults to null if value is not possible.
     */
    public function __construct($val = null, $position = 0, $leader = null)
    {
        // Default to clear if the stop type is not matched
        $this->val = (self::isStopType($val)) ? $val : 'clear';

        // Default to 0 if the position is non-numeric
        $this->position = (is_numeric($position)) ? intval($position) : 0;

        // Default to null if no tab leader
        $this->leader = (self::isLeaderType($leader)) ? $leader : null;
    }

    /**
     * Get stop type
     *
     * @return string
     */
    public function getStopType()
    {
        return $this->val;
    }

    /**
     * Get leader
     *
     * @return string
     */
    public function getLeader()
    {
        return $this->leader;
    }

    /**
     * Get position
     *
     * @return integer
     */
    public function getPosition()
    {
        return $this->position;
    }

    /**
     * Test if attribute is a valid stop type.
     *
     * @param string $attribute
     * @return bool True if it is; false otherwise.
     */
    private static function isStopType($attribute)
    {
        return in_array($attribute, self::$possibleStopTypes);
    }

    /**
     * Test if attribute is a valid leader type.
     *
     * @param string $attribute
     * @return bool True if it is; false otherwise.
     */
    private static function isLeaderType($attribute)
    {
        return in_array($attribute, self::$possibleLeaders);
    }
}