Manage bp_nav & bp_options_nav backcompat in this plugin

See https://buddypress.trac.wordpress.org/ticket/8927
Fixes #13

inc/core/classes/class-bp-classic-core-legacy-nav-backcompat.php

@@ -0,0 +1,273 @@
+<?php
+/**
+ * Backward compatibility for the $bp->bp_nav global.
+ *
+ * @package bp-classic\inc\groups\classes
+ * @since 1.0.0
+ */
+
+// Exit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
+
+/**
+ * Backward compatibility class for the `bp_nav` global.
+ *
+ * This class is used to provide backward compatibility for extensions that access and modify
+ * the $bp->bp_nav global.
+ *
+ * @since 1.0.0
+ */
+class BP_Classic_Core_Legacy_Nav_BackCompat implements ArrayAccess {
+	/**
+	 * Nav items.
+	 *
+	 * @since 1.0.0
+	 * @access public
+	 * @var array
+	 */
+	public $backcompat_nav = array();
+
+	/**
+	 * Component to which nav items belong.
+	 *
+	 * @since 1.0.0
+	 * @access public
+	 * @var array
+	 */
+	public $component;
+
+	/**
+	 * Constructor.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param array $backcompat_nav Optional. Array of nav items.
+	 */
+	public function __construct( $backcompat_nav = array() ) {
+		foreach ( $backcompat_nav as $key => $value ) {
+			if ( is_array( $value ) ) {
+				$this->backcompat_nav[ $key ] = new self( $value );
+			} else {
+				$this->backcompat_nav[ $key ] = $value;
+			}
+		}
+	}
+
+	/**
+	 * Assign a value to the nav array at the specified offset.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param mixed $offset Array offset.
+	 * @param array $value  Nav item.
+	 */
+	#[ReturnTypeWillChange]
+	public function offsetSet( $offset, $value ) {
+		_doing_it_wrong(
+			'bp_nav',
+			esc_html__( 'The bp_nav and bp_options_nav globals should not be used directly and are deprecated. Please use the BuddyPress nav functions instead.', 'bp-classic' ),
+			'BuddyPress 2.6.0'
+		);
+
+		$bp = buddypress();
+
+		if ( is_array( $value ) ) {
+			$value = new self( $value );
+		}
+
+		if ( null !== $offset ) {
+			// Temporarily set the backcompat_nav.
+			$this->backcompat_nav[ $offset ] = $value;
+
+			$args = $this->to_array();
+			if ( isset( $args['parent_slug'] ) ) {
+				$this->get_component_nav( $args['parent_slug'] )->edit_nav( $args, $args['slug'], $args['parent_slug'] );
+			} elseif ( isset( $args['slug'] ) ) {
+				$bp->members->nav->edit_nav( $args, $args['slug'] );
+			}
+		}
+	}
+
+	/**
+	 * Get a value of the nav array at the specified offset.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param mixed $offset Array offset.
+	 * @return BP_Classic_Core_Legacy_Nav_BackCompat
+	 */
+	#[ReturnTypeWillChange]
+	public function offsetGet( $offset ) {
+		_doing_it_wrong(
+			'bp_nav',
+			esc_html__( 'The bp_nav and bp_options_nav globals should not be used directly and are deprecated. Please use the BuddyPress nav functions instead.', 'bp-classic' ),
+			'BuddyPress 2.6.0'
+		);
+
+		$nav = $this->get_nav( $offset );
+		if ( $nav && isset( $nav[ $offset ] ) ) {
+			$this->backcompat_nav[ $offset ] = new self( $nav[ $offset ] );
+		}
+
+		return $this->backcompat_nav[ $offset ];
+	}
+
+	/**
+	 * Check whether nav array has a value at the specified offset.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param mixed $offset Array offset.
+	 * @return bool
+	 */
+	#[ReturnTypeWillChange]
+	public function offsetExists( $offset ) {
+		_doing_it_wrong(
+			'bp_nav',
+			esc_html__( 'The bp_nav and bp_options_nav globals should not be used directly and are deprecated. Please use the BuddyPress nav functions instead.', 'bp-classic' ),
+			'BuddyPress 2.6.0'
+		);
+
+		if ( isset( $this->backcompat_nav[ $offset ] ) ) {
+			return true;
+		}
+
+		$nav = $this->get_nav( $offset );
+		if ( $nav && isset( $nav[ $offset ] ) ) {
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Unset a nav array value at the specified offset.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param mixed $offset Array offset.
+	 */
+	#[ReturnTypeWillChange]
+	public function offsetUnset( $offset ) {
+		_doing_it_wrong(
+			'bp_nav',
+			esc_html__( 'The bp_nav and bp_options_nav globals should not be used directly and are deprecated. Please use the BuddyPress nav functions instead.', 'bp-classic' ),
+			'BuddyPress 2.6.0'
+		);
+
+		// For top-level nav items, the backcompat nav hasn't yet been initialized.
+		if ( ! isset( $this->backcompat_nav[ $offset ] ) ) {
+			buddypress()->members->nav->delete_nav( $offset );
+			unset( $this->backcompat_nav[ $offset ] );
+		}
+	}
+
+	/**
+	 * Set the component to which the nav belongs.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param string $component The ID of the component.
+	 */
+	public function set_component( $component ) {
+		$this->component = $component;
+	}
+
+	/**
+	 * Get the component to which the a nav item belongs.
+	 *
+	 * We use the following heuristic to guess, based on an offset, which component the item belongs to:
+	 *   - If this is a group, and the offset is the same as the current group's slug, it's a group nav item.
+	 *   - Otherwise, it's a member nav item.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param mixed $offset Array offset.
+	 * @return string|array
+	 */
+	public function get_component( $offset = '' ) {
+		if ( ! isset( $this->component ) ) {
+			if ( bp_is_active( 'groups' ) && bp_get_current_group_slug() === $offset ) {
+				$this->component = 'groups';
+			} else {
+				$this->component = 'members';
+			}
+		}
+
+		return $this->component;
+	}
+
+	/**
+	 * Reset the cached nav items.
+	 *
+	 * Called when the nav API removes items from the nav array.
+	 *
+	 * @since 1.0.0
+	 */
+	public function reset() {
+		$this->backcompat_nav = array();
+	}
+
+	/**
+	 * Get the nav object corresponding to the specified offset.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param mixed $offset Array offset.
+	 * @return bool|array
+	 */
+	protected function get_nav( $offset ) {
+		$component_nav = $this->get_component_nav( $offset );
+		$primary_nav   = $component_nav->get_primary( array( 'slug' => $offset ), false );
+
+		$nav = array();
+
+		if ( empty( $primary_nav ) ) {
+			return $nav;
+		}
+
+		foreach ( $primary_nav as $item ) {
+			$nav[ $item->slug ] = (array) $item;
+		}
+
+		return $nav;
+	}
+
+	/**
+	 * Get the BP_Core_Nav object corresponding to the component, based on a nav item name.
+	 *
+	 * The way bp_nav was previously organized makes it impossible to know for sure which component's nav is
+	 * being referenced by a given nav item name. We guess in the following manner:
+	 *   - If we're looking at a group, and the nav item name (`$offset`) is the same as the slug of the current
+	 *     group, we assume that the proper component nav is 'groups'.
+	 *   - Otherwise, fall back on 'members'.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param string $offset Nav item name.
+	 * @return BP_Core_Nav
+	 */
+	protected function get_component_nav( $offset = '' ) {
+		$component = $this->get_component( $offset );
+
+		$bp = buddypress();
+		if ( ! isset( $bp->{$component}->nav ) ) {
+			return false;
+		}
+
+		return $bp->{$component}->nav;
+	}
+
+	/**
+	 * Get the nav data, formatted as a flat array.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @return array
+	 */
+	protected function to_array() {
+		return $this->backcompat_nav;
+	}
+}