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<?php

/**
 * Re-save permalink settings on plugin activation or plugin updates.
 */
function ccd_set_permalink() {

	$is_permalink_reset = get_option( 'is_permalink_reset' );

	if ( '' === $is_permalink_reset || 'no' === $is_permalink_reset ) {
		flush_rewrite_rules();
		update_option( 'is_permalink_reset', 'yes' );
	}

}
add_action( 'admin_init', 'ccd_set_permalink' );

/**
 * Plugin deactivation.
 */
function ccd_plugin_deactivate() {

	update_option( 'is_permalink_reset', 'no' );

}
register_deactivation_hook( __FILE__, 'ccd_plugin_deactivate' );