<?php
/**
 * HTML_Common2: port of HTML_Common package to PHP5
 *
 * PHP version 5
 *
 * LICENSE:
 *
 * Copyright (c) 2004-2010, Alexey Borzov <avb@php.net>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *    * The names of the authors may not be used to endorse or promote products
 *      derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @category   HTML
 * @package    HTML_Common2
 * @author     Alexey Borzov <avb@php.net>
 * @license    http://opensource.org/licenses/bsd-license.php New BSD License
 * @version    CVS: $Id: Common2.php 304516 2010-10-19 18:43:58Z avb $
 * @link       http://pear.php.net/package/HTML_Common2
 */

/**
 * Base class for HTML classes
 *
 * Implements methods for working with HTML attributes, parsing and generating
 * attribute strings. Port of HTML_Common class for PHP4 originally written by
 * Adam Daniel with contributions from numerous other developers.
 *
 * @category   HTML
 * @package    HTML_Common2
 * @author     Alexey Borzov <avb@php.net>
 * @version    Release: 2.0.0
 */
abstract class HTML_Common2
{
   /**
    * Associative array of attributes
    * @var array
    */
    protected $attributes = array();

   /**
    * List of attribites changes to which will be announced via onAttributeChange()
    * method rather than performed by HTML_Common2 class itself
    * @var array
    * @see onAttributeChange()
    */
    protected $watchedAttributes = array();

   /**
    * Indentation level of the element
    * @var int
    */
    private $_indentLevel = 0;

   /**
    * Comment associated with the element
    * @var string
    */
    private $_comment = null;

   /**
    * Global options for all elements generated by subclasses of HTML_Common2
    *
    * Preset options are
    * - 'charset': charset parameter used in htmlspecialchars() calls,
    *   defaults to 'ISO-8859-1'
    * - 'indent': string used to indent HTML elements, defaults to "\11"
    * - 'linebreak': string used to indicate linebreak, defaults to "\12"
    *
    * @var array
    */
    private static $_options = array(
        'charset'   => 'ISO-8859-1',
        'indent'    => "\11",
        'linebreak' => "\12"
    );

   /**
    * Sets global option(s)
    *
    * @param    string|array    Option name or array ('option name' => 'option value')
    * @param    mixed           Option value, if first argument is not an array
    */
    public static function setOption($nameOrOptions, $value = null)
    {
        if (is_array($nameOrOptions)) {
            foreach ($nameOrOptions as $k => $v) {
                self::setOption($k, $v);
            }
        } else {
            $linebreaks = array('win' => "\15\12", 'unix' => "\12", 'mac' => "\15");
            if ('linebreak' == $nameOrOptions && isset($linebreaks[$value])) {
                $value = $linebreaks[$value];
            }
            self::$_options[$nameOrOptions] = $value;
        }
    }

   /**
    * Returns global option(s)
    *
    * @param    string  Option name
    * @return   mixed   Option value, null if option does not exist,
    *                   array of all options if $name is not given
    */
    public static function getOption($name = null)
    {
        if (null === $name) {
            return self::$_options;
        } else {
            return isset(self::$_options[$name])? self::$_options[$name]: null;
        }
    }

   /**
    * Parses the HTML attributes given as string
    *
    * @param    string  HTML attribute string
    * @return   array   An associative aray of attributes
    */
    protected static function parseAttributes($attrString)
    {
        $attributes = array();
        if (preg_match_all(
                "/(([A-Za-z_:]|[^\\x00-\\x7F])([A-Za-z0-9_:.-]|[^\\x00-\\x7F])*)" .
                "([ \\n\\t\\r]+)?(=([ \\n\\t\\r]+)?(\"[^\"]*\"|'[^']*'|[^ \\n\\t\\r]*))?/",
                $attrString,
                $regs
           )) {
            for ($i = 0; $i < count($regs[1]); $i++) {
                $name  = trim($regs[1][$i]);
                $check = trim($regs[0][$i]);
                $value = trim($regs[7][$i]);
                if ($name == $check) {
                    $attributes[strtolower($name)] = strtolower($name);
                } else {
                    if (!empty($value) && ($value[0] == '\'' || $value[0] == '"')) {
                        $value = substr($value, 1, -1);
                    }
                    $attributes[strtolower($name)] = $value;
                }
            }
        }
        return $attributes;
    }

   /**
    * Creates a valid attribute array from either a string or an array
    *
    * @param    mixed   Array of attributes or HTML attribute string
    * @return   array   An associative aray of attributes
    */
    protected static function prepareAttributes($attributes)
    {
        $prepared = array();
        if (is_string($attributes)) {
            return self::parseAttributes($attributes);

        } elseif (is_array($attributes)) {
            foreach ($attributes as $key => $value) {
                if (is_int($key)) {
                    $key = strtolower($value);
                    $prepared[$key] = $key;
                } else {
                    $prepared[strtolower($key)] = (string)$value;
                }
            }
        }
        return $prepared;
    }

   /**
    * Removes an attribute from an attribute array
    *
    * @param    array   Attribute array
    * @param    string  Name of attribute to remove
    */
    protected static function removeAttributeArray(array &$attributes, $name)
    {
        unset($attributes[strtolower($name)]);
    }

   /**
    * Creates HTML attribute string from array
    *
    * @param    array   Attribute array
    * @return   string  Attribute string
    */
    protected static function getAttributesString(array $attributes)
    {
        $str     = '';
        $charset = self::getOption('charset');
        foreach ($attributes as $key => $value) {
            $str .= ' ' . $key . '="' . htmlspecialchars($value, ENT_QUOTES, $charset) . '"';
        }
        return $str;
    }

   /**
    * Class constructor, sets default attributes
    *
    * @param    mixed   Array of attribute 'name' => 'value' pairs or HTML attribute string
    */
    public function __construct($attributes = null)
    {
        $this->mergeAttributes($attributes);
    }

   /**
    * Sets the value of the attribute
    *
    * @param    string  Attribute name
    * @param    string  Attribute value (will be set to $name if omitted)
    * @return   HTML_Common2
    */
    public function setAttribute($name, $value = null)
    {
        $name = strtolower($name);
        if (is_null($value)) {
            $value = $name;
        }
        if (in_array($name, $this->watchedAttributes)) {
            $this->onAttributeChange($name, $value);
        } else {
            $this->attributes[$name] = (string)$value;
        }
        return $this;
    }

   /**
    * Returns the value of an attribute
    *
    * @param    string  Attribute name
    * @return   string  Attribute value, null if attribute does not exist
    */
    public function getAttribute($name)
    {
        $name = strtolower($name);
        return isset($this->attributes[$name])? $this->attributes[$name]: null;
    }

   /**
    * Sets the attributes
    *
    * @param    mixed   Array of attribute 'name' => 'value' pairs or HTML attribute string
    * @return   HTML_Common2
    */
    public function setAttributes($attributes)
    {
        $attributes = self::prepareAttributes($attributes);
        $watched    = array();
        foreach ($this->watchedAttributes as $watchedKey) {
            if (isset($attributes[$watchedKey])) {
                $this->setAttribute($watchedKey, $attributes[$watchedKey]);
                unset($attributes[$watchedKey]);
            } else {
                $this->removeAttribute($watchedKey);
            }
            if (isset($this->attributes[$watchedKey])) {
                $watched[$watchedKey] = $this->attributes[$watchedKey];
            }
        }
        $this->attributes = array_merge($watched, $attributes);
        return $this;
    }

   /**
    * Returns the attribute array or string
    *
    * @param    bool    Whether to return attributes as string
    * @return   mixed   Either an array or string of attributes
    */
    public function getAttributes($asString = false)
    {
        if ($asString) {
            return self::getAttributesString($this->attributes);
        } else {
            return $this->attributes;
        }
    }

   /**
    * Merges the existing attributes with the new ones
    *
    * @param    mixed   Array of attribute 'name' => 'value' pairs or HTML attribute string
    * @return   HTML_Common2
    */
    public function mergeAttributes($attributes)
    {
        $attributes = self::prepareAttributes($attributes);
        foreach ($this->watchedAttributes as $watchedKey) {
            if (isset($attributes[$watchedKey])) {
                $this->onAttributeChange($watchedKey, $attributes[$watchedKey]);
                unset($attributes[$watchedKey]);
            }
        }
        $this->attributes = array_merge($this->attributes, $attributes);
        return $this;
    }

   /**
    * Removes an attribute
    *
    * @param    string  Name of attribute to remove
    * @return   HTML_Common2
    */
    public function removeAttribute($attribute)
    {
        if (in_array(strtolower($attribute), $this->watchedAttributes)) {
            $this->onAttributeChange(strtolower($attribute), null);
        } else {
            self::removeAttributeArray($this->attributes, $attribute);
        }
        return $this;
    }

   /**
    * Sets the indentation level
    *
    * @param    int
    * @return   HTML_Common2
    */
    public function setIndentLevel($level)
    {
        $level = intval($level);
        if (0 <= $level) {
            $this->_indentLevel = $level;
        }
        return $this;
    }

   /**
    * Gets the indentation level
    *
    * @return   int
    */
    public function getIndentLevel()
    {
        return $this->_indentLevel;
    }

   /**
    * Returns the string to indent the element
    *
    * @return   string
    */
    protected function getIndent()
    {
        return str_repeat(self::getOption('indent'), $this->getIndentLevel());
    }

   /**
    * Sets the comment for the element
    *
    * @param    string
    * @return   HTML_Common2
    */
    public function setComment($comment)
    {
        $this->_comment = $comment;
        return $this;
    }

   /**
    * Returns the comment associated with the element
    *
    * @return   string
    */
    public function getComment()
    {
        return $this->_comment;
    }

   /**
    * Checks whether the element has given CSS class
    *
    * @param    string  Class name
    * @return   bool
    */
    public function hasClass($class)
    {
        $regex = '/(^|\s)' . preg_quote($class, '/') . '(\s|$)/';
        return (bool)preg_match($regex, $this->getAttribute('class') ?? '');
    }

   /**
    * Adds the given CSS class(es) to the element
    *
    * @param    string|array    Class name, multiple class names separated by
    *                           whitespace, array of class names
    * @return   HTML_Common2
    */
    public function addClass($class)
    {
        if (!is_array($class)) {
            $class = preg_split('/\s+/', $class, null, PREG_SPLIT_NO_EMPTY);
        }
        $curClass = preg_split('/\s+/', $this->getAttribute('class'),
                               null, PREG_SPLIT_NO_EMPTY);
        foreach ($class as $c) {
            if (!in_array($c, $curClass)) {
                $curClass[] = $c;
            }
        }
        $this->setAttribute('class', implode(' ', $curClass));

        return $this;
    }

   /**
    * Removes the given CSS class(es) from the element
    *
    * @param    string|array    Class name, multiple class names separated by
    *                           whitespace, array of class names
    * @return   HTML_Common2
    */
    public function removeClass($class)
    {
        if (!is_array($class)) {
            $class = preg_split('/\s+/', $class, null, PREG_SPLIT_NO_EMPTY);
        }
        $curClass = array_diff(
            preg_split('/\s+/', $this->getAttribute('class'),
                       null, PREG_SPLIT_NO_EMPTY),
            $class
        );
        if (0 == count($curClass)) {
            $this->removeAttribute('class');
        } else {
            $this->setAttribute('class', implode(' ', $curClass));
        }
        return $this;
    }

   /**
    * Returns the HTML representation of the element
    *
    * This magic method allows using the instances of HTML_Common2 in string
    * contexts
    *
    * @return string
    */
    abstract public function __toString();

   /**
    * Called if trying to change an attribute with name in $watchedAttributes
    *
    * This method is called for each attribute whose name is in the
    * $watchedAttributes array and which is being changed by setAttribute(),
    * setAttributes() or mergeAttributes() or removed via removeAttribute().
    * Note that the operation for the attribute is not carried on after calling
    * this method, it is the responsibility of this method to change or remove
    * (or not) the attribute.
    *
    * @param    string  Attribute name
    * @param    string  Attribute value, null if attribute is being removed
    */
    protected function onAttributeChange($name, $value = null)
    {
    }
}