<?php

class Site_Switch_Language_Command extends WP_CLI\CommandWithTranslation {
    protected $obj_type = 'core';

    /**
     * Activates a given language.
     *
     * ## OPTIONS
     *
     * <language>
     * : Language code to activate.
     *
     * ## EXAMPLES
     *
     *     $ wp site switch-language ja
     *     Success: Language activated.
     *
     * @throws WP_CLI\ExitException
     */
    public function __invoke( $args, $assoc_args ) {
        list( $language_code ) = $args;

        $available = $this->get_installed_languages();

        if ( ! in_array( $language_code, $available, true ) ) {
            WP_CLI::error( 'Language not installed.' );
        }

        if ( 'en_US' === $language_code ) {
            $language_code = '';
        }

        if ( get_locale() === $language_code ) {
            WP_CLI::warning( "Language '{$language_code}' already active." );

            return;
        }

        update_option( 'WPLANG', $language_code );

        WP_CLI::success( 'Language activated.' );
    }
}