// /**
//  * Copyright (C) 2013 Crossing Hippos - Babs Gösgens. All rights reserved.
//  * Licensed under GNU General Public License version 2 or later !default; see LICENSE.txt
//  *
//  * Uses Hugo Giraudel's awesome Lists functions: https://github.com/HugoGiraudel
//  *
//  */
@if $trace-imports { @debug 'imported'; }


// Dependencies 
@import "pg/helpers/library/lists";


//  Returns a new element
//  ==========================================================================
//  @example $button: new('button', 'default');
//  @example $button: new($button, 'active');
//  --------------------------------------------------------------------------
//  @param $properties [Literal] an arbitrary string, or an existing $element
//  @param $name [String] a namespace for the new element
//  --------------------------------------------------------------------------
//  @return [List]

	@function new($properties, $name, $is-state)
	{
		@if type-of($properties)!=list {
			@return ($name, (), $is-state);
		}
		@else if type-of($properties)==list and length($properties)==1 {
			@return ($name, $properties, $is-state);
		}
		@else {
			$old_name: nth($properties, 1);
			@return replace($properties, $old_name, $name);
		}
	}


//  Placeholder function for new()
//  ==========================================================================
//  @example $button: clone($button, 'new-name');
//  
//  @param $element [List] an existing $element
//  @param $name [String] a namespace for the new element
//  --------------------------------------------------------------------------
//  @return [List]

	@function clone($element, $element-name, $is-state)
	{
		@return new($element, $element-name, $is-state);
	}


//  Returns the $element with adjusted properties
//  ==========================================================================
//  @example $button: change($button, (color, #fff));
//  
//  @param $element [List] an existing $element
//  @param $property [List] a list consisting of property-name and value
//  --------------------------------------------------------------------------
//  @return [List]

	@function change($element, $property)
	{
		$key: nth($property, 1);
		$properties: nth($element,2);
		$new_properties: ();

		$item: find-list-item($properties, $key);

		@if $item==false {
			$new_properties: append($properties, ($property));
		}
		@else {
			$new_properties: replace($properties, $item, $property);
		}
		$element: replace($element, $properties, $new_properties);

		@return $element;
	}


//  Returns a matching element from a nested list
//  ==========================================================================
//  @example $button: find-list-item( ((color, blue) (border: none)), border ) => (border: none)
//  @example $button: find-list-item( ((color, blue) (border: none)), border, true ) => 2
//  
//  @param $list [List] a nested list
//  @param $key [String] the key to match
//  @param $index [Boolean] return the match's index (true) or the match (false)
//  --------------------------------------------------------------------------
//  @return [Literal]

	@function find-list-item($list, $key, $index: false)
	{
		$l: length($list);
		@for $i from 1 through $l {
			$item: nth($list,$i);
			@if nth($item,1) == $key {
				@return $item;
			}
		}

		@return false;
	}