<?php
/**
 * Review queue / dashboard badge — a query-driven "awaiting your review" surface:
 * an admin-bar count (site-wide) + a Dashboard widget listing the items. Because it
 * queries current statuses, it self-heals (an item leaving a status drops off).
 *
 * @package OST\EditorialWorkflow
 */

namespace OST\EditorialWorkflow\Notifications;

use OST\EditorialWorkflow\Config;
use OST\EditorialWorkflow\Workflow;

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

/**
 * Surfaces items awaiting the current user's review.
 */
class ReviewQueue {

	/**
	 * Config service.
	 *
	 * @var Config
	 */
	private $config;

	/**
	 * Workflow service.
	 *
	 * @var Workflow
	 */
	private $workflow;

	/**
	 * Constructor.
	 *
	 * @param Config   $config   Config service.
	 * @param Workflow $workflow Workflow service.
	 */
	public function __construct( Config $config, Workflow $workflow ) {
		$this->config   = $config;
		$this->workflow = $workflow;
	}

	/**
	 * Register hooks.
	 *
	 * @return void
	 */
	public function register_hooks() {
		add_action( 'admin_bar_menu', array( $this, 'admin_bar' ), 80 );
		add_action( 'wp_dashboard_setup', array( $this, 'dashboard_widget' ) );
	}

	/**
	 * The statuses the given user is an approver for (across all workflows).
	 *
	 * @param \WP_User $user User.
	 * @return string[]
	 */
	private function statuses_for_user( $user ) {
		$out = array();

		// Someone who may approve on every step sees every approval step. Without
		// this the queue disagrees with Workflow::allowed_actions(), and an
		// administrator who can approve is shown nothing to approve.
		$is_global = $this->workflow->is_global_approver( $user );

		foreach ( $this->config->all() as $workflow ) {
			if ( empty( $workflow['steps'] ) ) {
				continue;
			}
			foreach ( $workflow['steps'] as $step ) {
				if ( ! isset( $step['approver_roles'], $step['status'] ) ) {
					continue;
				}
				if ( $is_global || array_intersect( (array) $step['approver_roles'], (array) $user->roles ) ) {
					$out[] = $step['status'];
				}
			}
		}
		return array_values( array_unique( $out ) );
	}

	/**
	 * Posts awaiting the current user.
	 *
	 * @param int $limit Max items.
	 * @return \WP_Post[]
	 */
	public function queue( $limit = 50 ) {
		$user = wp_get_current_user();
		if ( ! $user || ! $user->ID ) {
			return array();
		}
		$statuses = $this->statuses_for_user( $user );
		if ( empty( $statuses ) ) {
			return array();
		}
		return get_posts(
			array(
				'post_type'   => $this->config->managed_post_types(),
				'post_status' => $statuses,
				'numberposts' => $limit,
				'orderby'     => 'modified',
				'order'       => 'ASC',
			)
		);
	}

	/**
	 * Cached count for the current user (short TTL keeps it cheap + fresh enough).
	 *
	 * @return int
	 */
	public function count() {
		$user = wp_get_current_user();
		if ( ! $user || ! $user->ID ) {
			return 0;
		}
		$key    = 'ostew_qcount_' . $user->ID;
		$cached = get_transient( $key );
		if ( false !== $cached ) {
			return (int) $cached;
		}
		$count = count( $this->queue( 200 ) );
		set_transient( $key, $count, 2 * MINUTE_IN_SECONDS );
		return $count;
	}

	/**
	 * Admin-bar node showing the pending count.
	 *
	 * @param \WP_Admin_Bar $bar Admin bar.
	 * @return void
	 */
	public function admin_bar( $bar ) {
		if ( ! is_user_logged_in() ) {
			return;
		}
		$count = $this->count();
		if ( $count < 1 ) {
			return;
		}
		$bar->add_node(
			array(
				'id'    => 'ostew-reviews',
				'title' => sprintf(
					/* translators: %d: number of items awaiting review. */
					_n( 'Reviews (%d)', 'Reviews (%d)', $count, 'ost-editorial-workflow' ),
					$count
				),
				'href'  => admin_url( 'index.php#ostew_review_queue' ),
				'meta'  => array( 'title' => __( 'Items awaiting your review', 'ost-editorial-workflow' ) ),
			)
		);
	}

	/**
	 * Register the dashboard widget.
	 *
	 * @return void
	 */
	public function dashboard_widget() {
		if ( empty( $this->statuses_for_user( wp_get_current_user() ) ) ) {
			return;
		}
		wp_add_dashboard_widget( 'ostew_review_queue', __( 'Awaiting your review', 'ost-editorial-workflow' ), array( $this, 'render_widget' ) );
	}

	/**
	 * Render the dashboard widget contents.
	 *
	 * @return void
	 */
	public function render_widget() {
		$items = $this->queue( 25 );
		echo '<div id="ostew-review-queue">';
		if ( empty( $items ) ) {
			echo '<p>' . esc_html__( 'Nothing is waiting on you right now.', 'ost-editorial-workflow' ) . '</p></div>';
			return;
		}
		echo '<ul>';
		foreach ( $items as $post ) {
			$workflow = $this->workflow->for_post( $post );
			$label    = $workflow ? $this->workflow->status_label( $workflow, $post->post_status ) : $post->post_status;
			printf(
				'<li><a href="%1$s">%2$s</a> <span class="ostew-q-status">— %3$s</span></li>',
				esc_url( (string) get_edit_post_link( $post->ID ) ),
				esc_html( get_the_title( $post ) ),
				esc_html( $label )
			);
		}
		echo '</ul></div>';
	}
}