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<?php
/**
 * Plugin Name: WooCommerce Category Images Modification
 * Plugin URI: http://blog.ashfame.com/?p=1117
 * Description: Use product image as its category image on category archive pages (To override image for product category, upload one for that category and it will override)
 * Author: Ashfame
 * Version: 0.1.2
 * Author URI: http://ashfame.com/
 */

class WooCommerce_Category_Images_From_Product {

	private $let_category_image_override = true;
	private $randomize_category_image_from_products = true;

	public function __construct() {
		// Unhooking core's and hooking our custom thumbnail
		add_action( 'plugins_loaded', array( $this, 'overrides' ) );
		add_action( 'woocommerce_before_subcategory_title', array( $this, 'add_product_image_as_woocommerce_subcategory_thumbnail' ) );

		// Support link in plugins listing
		add_filter( 'plugin_action_links', array( $this, 'support_plugin_action_link' ), 10, 2 );
	}

	public function overrides() {
		remove_action( 'woocommerce_before_subcategory_title', 'woocommerce_subcategory_thumbnail', 10 );
	}

	public function add_product_image_as_woocommerce_subcategory_thumbnail( $category ) {

		if ( $this->let_category_image_override ) {
			if ( get_woocommerce_term_meta( $category->term_id, 'thumbnail_id', true ) ) {
				woocommerce_subcategory_thumbnail( $category );
				return;
			}
		}

		$query_args = array(
			'posts_per_page' => $this->randomize_category_image_from_products ? 10 : 1,
			'post_status' => 'publish',
			'post_type' => 'product',
			'meta_query' => array(
				array(
					'key' => '_visibility',
					'value' => array( 'catalog', 'visible' ),
					'compare' => 'IN'
				)
			),
			'tax_query' => array(
				array(
					'taxonomy' => 'product_cat',
					'field' => 'id',
					'terms' => $category->term_id
				)
			)
		);

		$products = get_posts( $query_args );

		if ( $products ) {
			echo get_the_post_thumbnail( $products[ array_rand( $products ) ]->ID, 'shop_thumbnail' );
		}
	}

	public function support_plugin_action_link( $links, $file ) {
		if ( $file == plugin_basename( __FILE__ ) ) {
			$support_link = '<a href="mailto:mail@ashfame.com?subject=' . rawurlencode('Premium Support') . '">Premium Support</a>';
			array_unshift( $links, $support_link );
		}

		return $links;
	}
}

new WooCommerce_Category_Images_From_Product();