<?php

/* SVN FILE: $Id$ */

/**

 * SassNode class file.

 * @author      Chris Yates <chris.l.yates@gmail.com>

 * @copyright   Copyright (c) 2010 PBM Web Development

 * @license      http://phamlp.googlecode.com/files/license.txt

 * @package      PHamlP

 * @subpackage  Sass.tree

 */



require_once('SassContext.php');

require_once('SassCommentNode.php');

require_once('SassDebugNode.php');

require_once('SassDirectiveNode.php');

require_once('SassImportNode.php');

require_once('SassMixinNode.php');

require_once('SassMixinDefinitionNode.php');

require_once('SassPropertyNode.php');

require_once('SassRootNode.php');

require_once('SassRuleNode.php');

require_once('SassVariableNode.php');

require_once('SassExtendNode.php');

require_once('SassEachNode.php');

require_once('SassForNode.php');

require_once('SassIfNode.php');

require_once('SassElseNode.php');

require_once('SassWhileNode.php');

require_once('SassNodeExceptions.php');



require_once('SassFunctionDefinitionNode.php');

require_once('SassReturnNode.php');

require_once('SassContentNode.php');

require_once('SassWarnNode.php');

require_once('SassMediaNode.php');



/**

 * SassNode class.

 * Base class for all Sass nodes.

 * @package      PHamlP

 * @subpackage  Sass.tree

 */

class SassNode {

  /**

   * @var SassNode parent of this node

   */

  public $parent;

  /**

   * @var SassNode root node

   */

  public $root;

  /**

   * @var array children of this node

   */

  public $children = array();

  /**

   * @var object source token

   */

  public $token;



  /**

   * Constructor.

   * @param object source token

   * @return SassNode

   */

  public function __construct($token) {

    $this->token = $token;

  }



  /**

   * Getter.

   * @param string name of property to get

   * @return mixed return value of getter function

   */

  public function __get($name) {

    $getter = 'get' . ucfirst($name);

    if (method_exists($this, $getter)) {

      return $this->$getter();

    }

    throw new SassNodeException('No getter function for ' . $name, $this);

  }



  /**

   * Setter.

   * @param string name of property to set

   * @return mixed value of property

   * @return SassNode this node

   */

  public function __set($name, $value) {

    $setter = 'set' . ucfirst($name);

    if (method_exists($this, $setter)) {

      $this->$setter($value);

      return $this;

    }

    throw new SassNodeException('No setter function for ' . $name, $this);

  }



  /**

   * Resets children when cloned

   * @see parse

   */

  public function __clone() {

    $this->children = array();

  }



  /**

   * Return a value indicating if this node has a parent

   * @return array the node's parent

   */

  public function hasParent() {

    return !empty($this->parent);

  }



  /**

   * Returns the node's parent

   * @return array the node's parent

   */

  public function getParent() {

    return $this->parent;

  }



  /**

   * Adds a child to this node.

   * @return SassNode the child to add

   */

  public function addChild($child) {

    if ($child instanceof SassElseNode) {

      if (!$this->lastChild instanceof SassIfNode) {

        throw new SassException('@else(if) directive must come after @(else)if', $child);

      }

      $this->lastChild->addElse($child);

    }

    else {

      $this->children[] = $child;

      $child->parent = $this;

      $child->root = $this->root;

    }

    // The child will have children if a debug node has been added

    foreach ($child->children as $grandchild) {

      $grandchild->root = $this->root;

    }

  }



  /**

   * Returns a value indicating if this node has children

   * @return boolean true if the node has children, false if not

   */

  public function hasChildren() {

    return !empty($this->children);

  }



  /**

   * Returns the node's children

   * @return array the node's children

   */

  public function getChildren() {

    return $this->children;

  }



  /**

   * Returns a value indicating if this node is a child of the passed node.

   * This just checks the levels of the nodes. If this node is at a greater

   * level than the passed node if is a child of it.

   * @return boolean true if the node is a child of the passed node, false if not

   */

  public function isChildOf($node) {

    return $this->level > $node->level;

  }



  /**

   * Returns the last child node of this node.

   * @return SassNode the last child node of this node

   */

  public function getLastChild() {

    return $this->children[count($this->children) - 1];

  }



  /**

   * Returns the level of this node.

   * @return integer the level of this node

   */

  public function getLevel() {

    return $this->token->level;

  }



  /**

   * Returns the source for this node

   * @return string the source for this node

   */

  public function getSource() {

    return $this->token->source;

  }



  /**

   * Returns the debug_info option setting for this node

   * @return boolean the debug_info option setting for this node

   */

  public function getDebug_info() {

    return $this->parser->debug_info;

  }



  /**

   * Returns the line number for this node

   * @return string the line number for this node

   */

  public function getLine() {

    return $this->token->line;

  }



  /**

   * Returns the line_numbers option setting for this node

   * @return boolean the line_numbers option setting for this node

   */

  public function getLine_numbers() {

    return $this->parser->line_numbers;

  }



  /**

   * Returns the filename for this node

   * @return string the filename for this node

   */

  public function getFilename() {

    return $this->token->filename;

  }



  /**

   * Returns the Sass parser.

   * @return SassParser the Sass parser

   */

  public function getParser() {

    return $this->root->parser;

  }



  /**

   * Returns the property syntax being used.

   * @return string the property syntax being used

   */

  public function getPropertySyntax() {

    return $this->root->parser->propertySyntax;

  }



  /**

   * Returns the SassScript parser.

   * @return SassScriptParser the SassScript parser

   */

  public function getScript() {

    return $this->root->script;

  }



  /**

   * Returns the renderer.

   * @return SassRenderer the renderer

   */

  public function getRenderer() {

    return $this->root->renderer;

  }



  /**

   * Returns the render style of the document tree.

   * @return string the render style of the document tree

   */

  public function getStyle() {

    return $this->root->parser->style;

  }



  /**

   * Returns a value indicating whether this node is in a directive

   * @param boolean true if the node is in a directive, false if not

   */

  public function inDirective() {

    return $this->parent instanceof SassDirectiveNode ||

        $this->parent instanceof SassDirectiveNode;

  }



  /**

   * Returns a value indicating whether this node is in a SassScript directive

   * @param boolean true if this node is in a SassScript directive, false if not

   */

  public function inSassScriptDirective() {

    return $this->parent instanceof SassEachNode ||

      $this->parent->parent instanceof SassEachNode ||

      $this->parent instanceof SassForNode ||

      $this->parent->parent instanceof SassForNode ||

      $this->parent instanceof SassIfNode ||

      $this->parent->parent instanceof SassIfNode ||

      $this->parent instanceof SassWhileNode ||

      $this->parent->parent instanceof SassWhileNode;

  }



  /**

   * Evaluates a SassScript expression.

   * @param string expression to evaluate

   * @param SassContext the context in which the expression is evaluated

   * @return SassLiteral value of parsed expression

   */

  public function evaluate($expression, $context, $x=null) {

    $context->node = $this;

    return $this->script->evaluate($expression, $context, $x);

  }



  /**

   * Replace interpolated SassScript contained in '#{}' with the parsed value.

   * @param string the text to interpolate

   * @param SassContext the context in which the string is interpolated

   * @return string the interpolated text

   */

  public function interpolate($expression, $context) {

    $context->node = $this;

    return $this->script->interpolate($expression, $context);

  }



  /**

   * Adds a warning to the node.

   * @param string warning message

   * @param array line

   */

  public function addWarning($message) {

    $warning = new SassDebugNode($this->token, $message);

    $this->addChild($warning);

  }



  /**

   * Parse the children of the node.

   * @param SassContext the context in which the children are parsed

   * @return array the parsed child nodes

   */

  public function parseChildren($context) {

    $children = array();

    foreach ($this->children as $child) {

      # child could be a SassLiteral /or/ SassNode

      if (method_exists($child, 'parse')) {

        $kid = $child->parse($context);

      } else {

        $kid = array($child);

      }

      $children = array_merge($children, $kid);

    }

    return $children;

  }



  /**

   * Returns a value indicating if the token represents this type of node.

   * @param object token

   * @return boolean true if the token represents this type of node, false if not

   */

  public static function isa($token) {

    throw new SassNodeException('Child classes must override this method');

  }

}