<?php
/**
 * wp- e-Commerce Variations class
 *
 * This is the code that handles adding, editing and displaying variations on Products
 */


class wpsc_variations {
	// variation groups: i.e. colour, size
	var $variation_groups;
	var $variation_group_count = 0;
	var $current_variation_group = -1;
	var $variation_group;
	
	// for getting the product price
	var $first_variations;
	
	//variations inside variation groups: i.e. (red, green, blue) or (S, M, L, XL)
	var $variations;
	var $variation_count = 0;
	var $current_variation = -1;
	var $variation;
	

	function wpsc_variations($product_id) {
		global $wpdb;
		
		$product_terms = wp_get_object_terms($product_id, 'wpsc-variation');
		$this->variation_groups = array();
		$this->first_variations = array();
		$this->all_associated_variations = array();
		
		foreach($product_terms as $product_term) {
			if($product_term->parent > 0) {
				if(empty($this->all_associated_variations[$product_term->parent])){
					$this->all_associated_variations[$product_term->parent][0] =  new stdClass;
					$this->all_associated_variations[$product_term->parent][0]->term_id = 0;
					$this->all_associated_variations[$product_term->parent][0]->name = '-- Please Select --';
				}
				$this->all_associated_variations[$product_term->parent][] = $product_term;	
			} else {
				$this->variation_groups[] = $product_term;
			}
		}
		
		// Filters to hook into variations to sort etc.
		$this->variation_groups = apply_filters( 'wpsc_variation_groups', $this->variation_groups, $product_id );
		$this->all_associated_variations = apply_filters( 'wpsc_all_associated_variations', $this->all_associated_variations, $this->variation_groups, $product_id );
		
		foreach((array)$this->variation_groups as $variation_group) {
			$variation_id = $variation_group->term_id;
			$this->first_variations[] = $this->all_associated_variations[$variation_id][0]->term_id;
		}
		
		$this->variation_group_count = count($this->variation_groups);
	}
	

	/*
	 * (Variation Group and Variation) Loop Code Starts here
	*/
	function get_variation_groups() {
		global $wpdb;
		$this->variation_group_count = count($this->variation_groups);
		$this->get_first_variations();
	}
	
	
	function next_variation_group() {
		$this->current_variation_group++;
		$this->variation_group = $this->variation_groups[$this->current_variation_group];
		return $this->variation_group;
	}

	
	function the_variation_group() {
		$this->variation_group = $this->next_variation_group();
		$this->get_variations();
	}

	function have_variation_groups() {
		if ($this->current_variation_group + 1 < $this->variation_group_count) {
			return true;
		} else if ($this->current_variation_group + 1 == $this->variation_group_count && $this->variation_group_count > 0) {
			$this->rewind_variation_groups();
		}
		return false;
	}

	function rewind_variation_groups() {
		$this->current_variation_group = -1;
		if ($this->variation_group_count > 0) {
			$this->variation_group = $this->variation_groups[0];
		}
	}
	
	function get_first_variations() {
		global $wpdb;
		return null;
	}


	function get_variations() {
		global $wpdb;
		$this->variations = $this->all_associated_variations[$this->variation_group->term_id];
		$this->variation_count = count($this->variations);
	}
	
	
	function next_variation() {
		$this->current_variation++;
		$this->variation = $this->variations[$this->current_variation];
		return $this->variation;
	}

	
	function the_variation() {
		$this->variation = $this->next_variation();
	}

	function have_variations() {
		if ($this->current_variation + 1 < $this->variation_count) {
			return true;
		} else if ($this->current_variation + 1 == $this->variation_count && $this->variation_count > 0) {
			// Do some cleaning up after the loop,
			$this->rewind_variations();
		}
		return false;
	}

	function rewind_variations() {
		$this->current_variation = -1;
		if ($this->variation_count > 0) {
			$this->variation = $this->variations[0];
		}
	}	
	
	
}
function wpsc_get_child_object_in_select_terms($parent_id, $terms, $taxonomy){
	global $wpdb;
	$sql = "SELECT tr.`object_id` 
			FROM `".$wpdb->term_relationships."` AS tr
			LEFT JOIN `".$wpdb->posts."` AS posts
			ON posts.`ID` = tr.`object_id`				
			WHERE tr.`term_taxonomy_id` IN (".implode(',',$terms).") and posts.`post_parent`=".$parent_id;
	$products = $wpdb->get_col($sql);
	return $products;
	
}

/**
 * wpsc_get_child_objects_in_term function.
 * gets the 
 * 
 * @access public
 * @param mixed $parent_id
 * @param mixed $terms
 * @param mixed $taxonomies
 * @param array $args. (default: array())
 * @return void
 */
function wpsc_get_child_object_in_terms($parent_id, $terms, $taxonomies, $args = array() ) {
	global $wpdb, $current_version_number;
	$wpdb->show_errors = true;
	$parent_id = absint($parent_id);

	if ( !is_array( $terms) )
		$terms = array($terms);

	if ( !is_array($taxonomies) )
		$taxonomies = array($taxonomies);

	foreach ( (array) $taxonomies as $taxonomy ) {
		if ($current_version_number < 3.8) {
			if ( ! taxonomy_exists($taxonomy) )
				return new WP_Error('invalid_taxonomy', __('Invalid Taxonomy', 'wpsc'));
			} else {
			if ( !taxonomy_exists($taxonomy) )
				return new WP_Error('invalid_taxonomy', __('Invalid Taxonomy', 'wpsc'));
			}
			
	}

	$defaults = array('order' => 'ASC');
	$args = wp_parse_args( $args, $defaults );
	extract($args, EXTR_SKIP);

	$order = ( 'desc' == strtolower($order) ) ? 'DESC' : 'ASC';

	$terms = array_map('intval', $terms);
	
	$taxonomy_count = count($taxonomies);
	$term_count = count($terms);

	$taxonomies = "'" . implode("', '", $taxonomies) . "'";
	$terms = "'" . implode("', '", $terms) . "'";
	
	// This SQL statement finds the item associated with all variations in the selected combination that is a child of the target product
	$object_sql = "SELECT tr.object_id, COUNT(tr.object_id) AS `count`
	FROM {$wpdb->term_relationships} AS tr
	INNER JOIN {$wpdb->posts} AS posts
		ON posts.ID = tr.object_id
	INNER JOIN {$wpdb->term_taxonomy} AS tt
		ON tr.term_taxonomy_id = tt.term_taxonomy_id
	WHERE posts.post_parent = {$parent_id}
		AND tt.taxonomy IN ({$taxonomies})
		AND tt.term_id IN ({$terms})
		AND tt.parent > 0
		AND ( 
			SELECT COUNT(DISTINCT tt2.parent) FROM 
			{$wpdb->term_relationships} AS tr2
			INNER JOIN {$wpdb->term_taxonomy} AS tt2
				ON tr2.term_taxonomy_id = tt2.term_taxonomy_id
			WHERE tr2.object_id = tr.object_id
			AND tt2.taxonomy IN ({$taxonomies})
			AND tt2.parent > 0
		) = {$term_count}
	GROUP BY tr.object_id
	HAVING `count` = {$term_count}";
	$object_ids = $wpdb->get_row($object_sql, ARRAY_A);
	if (count($object_ids) > 0) {
		return $object_ids['object_id'];
	} else {
		
		return false;
	}
}


/**
 * wpsc_get_child_objects_in_term function.
 * gets the 
 * 
 * @access public
 * @param mixed $parent_id
 * @param mixed $terms
 * @param mixed $taxonomies
 * @param array $args. (default: array())
 * @return void
 */
function wpsc_get_child_object_in_terms_var($parent_id, $terms, $taxonomies, $args = array() ) {
	global $wpdb, $current_version_number;
	$wpdb->show_errors = true;
	$parent_id = absint($parent_id);

	if ( !is_array( $terms) )
		$terms = array($terms);

	if ( !is_array($taxonomies) )
		$taxonomies = array($taxonomies);

	foreach ( (array) $taxonomies as $taxonomy ) {
		if ($current_version_number < 3.8) {
			if ( ! taxonomy_exists($taxonomy) )
				return new WP_Error('invalid_taxonomy', __('Invalid Taxonomy', 'wpsc'));
			} else {
			if ( !taxonomy_exists($taxonomy) )
				return new WP_Error('invalid_taxonomy', __('Invalid Taxonomy', 'wpsc'));
			}
			
	}

	$defaults = array('order' => 'ASC');
	$args = wp_parse_args( $args, $defaults );
	extract($args, EXTR_SKIP);

	$order = ( 'desc' == strtolower($order) ) ? 'DESC' : 'ASC';

	$terms = array_map('intval', $terms);

	$taxonomies = "'" . implode("', '", $taxonomies) . "'";
	$terms = "'" . implode("', '", $terms) . "'";
	
	// This SQL statement finds the item associated with all variations in the selected combination that is a child of the target product
	$object_sql = "SELECT tr.object_id
	FROM {$wpdb->term_relationships} AS tr
	INNER JOIN {$wpdb->posts} AS posts
		ON posts.ID = tr.object_id
	INNER JOIN {$wpdb->term_taxonomy} AS tt
		ON tr.term_taxonomy_id = tt.term_taxonomy_id
	WHERE posts.post_parent = {$parent_id}
		AND tt.taxonomy IN ({$taxonomies})
		AND tt.term_id IN ({$terms})
		AND tt.parent > 0
	GROUP BY tr.object_id";
	$object_ids = $wpdb->get_results($object_sql, ARRAY_A);
	if (count($object_ids) > 0) {
		return $object_ids;
	} else {
		return false;
	}
}

?>