<?php
/**
 * REST API Reports controller
 *
 * Handles requests to the reports/top_sellers endpoint.
 *
 * @author   WooThemes
 * @category API
 * @package Automattic/WooCommerce/RestApi
 * @since    3.0.0
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * REST API Report Top Sellers controller class.
 *
 * @package Automattic/WooCommerce/RestApi
 * @extends WC_REST_Report_Sales_V1_Controller
 */
class WC_REST_Report_Top_Sellers_V1_Controller extends WC_REST_Report_Sales_V1_Controller {

	/**
	 * Endpoint namespace.
	 *
	 * @var string
	 */
	protected $namespace = 'wc/v1';

	/**
	 * Route base.
	 *
	 * @var string
	 */
	protected $rest_base = 'reports/top_sellers';

	/**
	 * Get sales reports.
	 *
	 * @param WP_REST_Request $request
	 * @return array|WP_Error
	 */
	public function get_items( $request ) {
		// Set date filtering.
		$filter = array(
			'period'   => $request['period'],
			'date_min' => $request['date_min'],
			'date_max' => $request['date_max'],
		);
		$this->setup_report( $filter );

		$report_data = $this->report->get_order_report_data( array(
			'data' => array(
				'_product_id' => array(
					'type'            => 'order_item_meta',
					'order_item_type' => 'line_item',
					'function'        => '',
					'name'            => 'product_id',
				),
				'_qty' => array(
					'type'            => 'order_item_meta',
					'order_item_type' => 'line_item',
					'function'        => 'SUM',
					'name'            => 'order_item_qty',
				),
			),
			'order_by'     => 'order_item_qty DESC',
			'group_by'     => 'product_id',
			'limit'        => isset( $filter['limit'] ) ? absint( $filter['limit'] ) : 12,
			'query_type'   => 'get_results',
			'filter_range' => true,
		) );

		$top_sellers = array();

		foreach ( $report_data as $item ) {
			$product = wc_get_product( $item->product_id );

			if ( $product ) {
				$top_sellers[] = array(
					'name'      => $product->get_name(),
					'product_id' => (int) $item->product_id,
					'quantity'   => wc_stock_amount( $item->order_item_qty ),
				);
			}
		}

		$data = array();
		foreach ( $top_sellers as $top_seller ) {
			$item   = $this->prepare_item_for_response( (object) $top_seller, $request );
			$data[] = $this->prepare_response_for_collection( $item );
		}

		return rest_ensure_response( $data );
	}

	/**
	 * Prepare a report sales object for serialization.
	 *
	 * @param stdClass $top_seller
	 * @param WP_REST_Request $request Request object.
	 * @return WP_REST_Response $response Response data.
	 */
	public function prepare_item_for_response( $top_seller, $request ) {
		$data = array(
			'name'       => $top_seller->name,
			'product_id' => $top_seller->product_id,
			'quantity'   => $top_seller->quantity,
		);

		$context = ! empty( $request['context'] ) ? $request['context'] : 'view';
		$data    = $this->add_additional_fields_to_object( $data, $request );
		$data    = $this->filter_response_by_context( $data, $context );

		// Wrap the data in a response object.
		$response = rest_ensure_response( $data );
		$response->add_links( array(
			'about' => array(
				'href' => rest_url( sprintf( '%s/reports', $this->namespace ) ),
			),
			'product' => array(
				'href' => rest_url( sprintf( '/%s/products/%s', $this->namespace, $top_seller->product_id ) ),
			),
		) );

		/**
		 * Filter a report top sellers returned from the API.
		 *
		 * Allows modification of the report top sellers data right before it is returned.
		 *
		 * @param WP_REST_Response $response   The response object.
		 * @param stdClass         $top_seller The original report object.
		 * @param WP_REST_Request  $request    Request used to generate the response.
		 */
		return apply_filters( 'woocommerce_rest_prepare_report_top_sellers', $response, $top_seller, $request );
	}

	/**
	 * Get the Report's schema, conforming to JSON Schema.
	 *
	 * @return array
	 */
	public function get_item_schema() {
		$schema = array(
			'$schema'    => 'http://json-schema.org/draft-04/schema#',
			'title'      => 'top_sellers_report',
			'type'       => 'object',
			'properties' => array(
				'name' => array(
					'description' => __( 'Product name.', 'woocommerce' ),
					'type'        => 'string',
					'context'     => array( 'view' ),
					'readonly'    => true,
				),
				'product_id' => array(
					'description' => __( 'Product ID.', 'woocommerce' ),
					'type'        => 'integer',
					'context'     => array( 'view' ),
					'readonly'    => true,
				),
				'quantity' => array(
					'description' => __( 'Total number of purchases.', 'woocommerce' ),
					'type'        => 'integer',
					'context'     => array( 'view' ),
					'readonly'    => true,
				),
			),
		);

		return $this->add_additional_fields_schema( $schema );
	}
}
