Method: Registers the inventory_vehicle post type that holds vehicles. The post type name is available in the API class constant INVP::POST_TYPE. The arguments array can be altered using the invp_post_type_args filter hook.

Method: Modifies the $query to filter vehicles by prices for the Maximum Price Filter widget.

Method: Filter callback. Modifies a query’s ORDER BY clause to appropriately sort some meta values as numbers instead of strings while adding fields to the ORDER BY clause to account for all of the JOINs to the postmeta.

Method: Registers all meta fields our custom post type uses to define a vehicle and its attachments.

Method: Registers every widget that ships with this plugin.

Method: Filter callback that changes a query’s meta_query value if the meta_query does not already contain the provided $key.

Method: Action hook callback that adds rewrite rules to the global $wp_rewrite.

Method: Change links to terms in our taxonomies to include /inventory before /tax/term.

Method: Deletes the rewrite_rules option so the rewrite rules are generated on the next page load without ours. Called during deactivation.

Method: Flushes rewrite rules.