// úprava registračního formuláře
// spolupracuje s https://cs.wordpress.org/plugins/woolab-ic-dic/
function wooc_extra_register_fields() {
?>
<strong>Vytvoření účtu neopravňuje k nákupu. Registrace nového účtu podléhá ručnímu schválení, o čemž budete informováni po kontrole údajů emailem.<br />Velkobchod VeloStore není určen pro soukromé osoby.</strong><br />Položky označené * jsou povinné.<br /><br />
       <label for="reg_billing_first_name"><?php _e( 'First name', 'woocommerce' ); ?><span class="required">*</span></label>
       <input type="text" class="input-text" name="billing_first_name" id="reg_billing_first_name" value="<?php if ( ! empty( $_POST['billing_first_name'] ) ) esc_attr_e( $_POST['billing_first_name'] ); ?>" />
       <label for="reg_billing_last_name"><?php _e( 'Last name', 'woocommerce' ); ?><span class="required">*</span></label>
       <input type="text" class="input-text" name="billing_last_name" id="reg_billing_last_name" value="<?php if ( ! empty( $_POST['billing_last_name'] ) ) esc_attr_e( $_POST['billing_last_name'] ); ?>" />
<div class="clear"></div>
       <label for="reg_billing_company"><?php _e( 'Název firmy, skupiny, spolku, klubu, nadace...', 'woocommerce' ); ?><span class="required">*</span></label>
       <input type="text" class="input-text" name="billing_company" id="reg_billing_company" value="<?php if ( ! empty( $_POST['billing_company'] ) ) esc_attr_e( $_POST['billing_company'] ); ?>" />
       <label for="reg_billing_ic"><?php _e( 'IČ', 'woocommerce' ); ?></label>
       <input type="text" class="input-text" name="billing_ic" id="reg_billing_ic" value="<?php if ( ! empty( $_POST['billing_ic'] ) ) esc_attr_e( $_POST['billing_ic'] ); ?>" />
       <label for="reg_billing_dic"><?php _e( 'DIČ', 'woocommerce' ); ?></label>
       <input type="text" class="input-text" name="billing_dic" id="reg_billing_dic" value="<?php if ( ! empty( $_POST['billing_dic'] ) ) esc_attr_e( $_POST['billing_dic'] ); ?>" />
<div class="clear"></div>
       <label for="reg_billing_phone"><?php _e( 'Phone', 'woocommerce' ); ?><span class="required">*</span></label>
       <input type="text" class="input-text" name="billing_phone" id="reg_billing_phone" value="<?php if ( ! empty( $_POST['billing_phone'] ) ) esc_attr_e( $_POST['billing_phone'] ); ?>" />
       <label for="reg_billing_address_1"><?php _e( 'Address', 'woocommerce' ); ?><span class="required">*</span></label>
       <input type="text" class="input-text" name="billing_address_1" id="reg_billing_address_1" value="<?php if ( ! empty( $_POST['billing_address_1'] ) ) esc_attr_e( $_POST['billing_address_1'] ); ?>" />
       <label for="reg_billing_city"><?php _e( 'City', 'woocommerce' ); ?><span class="required">*</span></label>
       <input type="text" class="input-text" name="billing_city" id="reg_billing_city" value="<?php if ( ! empty( $_POST['billing_city'] ) ) esc_attr_e( $_POST['billing_city'] ); ?>" />
       <label for="reg_billing_postcode"><?php _e( 'ZIP', 'woocommerce' ); ?><span class="required">*</span></label>
       <input type="text" class="input-text" name="billing_postcode" id="reg_billing_postcode" value="<?php if ( ! empty( $_POST['billing_postcode'] ) ) esc_attr_e( $_POST['billing_postcode'] ); ?>" />
<div class="clear"></div>
       <?php
}
add_action( 'woocommerce_register_form_start', 'wooc_extra_register_fields' );

// kontrola údajů
function wooc_validate_extra_register_fields( $username, $email, $validation_errors ) {
       if ( isset( $_POST['billing_first_name'] ) && empty( $_POST['billing_first_name'] ) ) {
              $validation_errors->add( 'billing_first_name_error', __( 'Jméno je povinná položka!', 'woocommerce' ) );
       }
       if ( isset( $_POST['billing_last_name'] ) && empty( $_POST['billing_last_name'] ) ) {
              $validation_errors->add( 'billing_last_name_error', __( 'Příjmení je povinná položka!.', 'woocommerce' ) );
       }
       if ( isset( $_POST['billing_phone'] ) && empty( $_POST['billing_phone'] ) ) {
              $validation_errors->add( 'billing_phone_error', __( 'Telefon je povinná položka!.', 'woocommerce' ) );
       }
       if ( isset( $_POST['billing_address_1'] ) && empty( $_POST['billing_address_1'] ) ) {
              $validation_errors->add( 'billing_address_1_error', __( 'Adresa je povinná položka!.', 'woocommerce' ) );
       }
       if ( isset( $_POST['billing_city'] ) && empty( $_POST['billing_city'] ) ) {
              $validation_errors->add( 'billing_city_error', __( 'Město je povinná položka!.', 'woocommerce' ) );
       }
       if ( isset( $_POST['billing_postcode'] ) && empty( $_POST['billing_postcode'] ) ) {
              $validation_errors->add( 'billing_postcode_error', __( 'PSČ je povinná položka!.', 'woocommerce' ) );
       }
       if ( isset( $_POST['billing_company'] ) && empty( $_POST['billing_company'] ) ) {
              $validation_errors->add( 'billing_company_error', __( 'Název firmy, spolku atd je povinná položka!.', 'woocommerce' ) );
       }	
}
add_action( 'woocommerce_register_post', 'wooc_validate_extra_register_fields', 10, 3 );

// uložení údajů zákazníka do databáze
function wooc_save_extra_register_fields( $customer_id ) {
       if ( isset( $_POST['billing_first_name'] ) ) {
              // WordPress default first name field.
              update_user_meta( $customer_id, 'first_name', sanitize_text_field( $_POST['billing_first_name'] ) );
              // WooCommerce billing first name.
              update_user_meta( $customer_id, 'billing_first_name', sanitize_text_field( $_POST['billing_first_name'] ) );
       }
       if ( isset( $_POST['billing_last_name'] ) ) {
              // aktualizujeme Jméno
              update_user_meta( $customer_id, 'last_name', sanitize_text_field( $_POST['billing_last_name'] ) );
              // aktualizujeme Příjmení
              update_user_meta( $customer_id, 'billing_last_name', sanitize_text_field( $_POST['billing_last_name'] ) );
       }
       if ( isset( $_POST['billing_phone'] ) ) {
              // aktualizujeme Telefon
              update_user_meta( $customer_id, 'billing_phone', sanitize_text_field( $_POST['billing_phone'] ) );
       }
       if ( isset( $_POST['billing_address_1'] ) ) {
              // aktualizujeme Adresu/ulici
              update_user_meta( $customer_id, 'billing_address_1', sanitize_text_field( $_POST['billing_address_1'] ) );
       }
       if ( isset( $_POST['billing_city'] ) ) {
              // aktualizujeme Město
              update_user_meta( $customer_id, 'billing_city', sanitize_text_field( $_POST['billing_city'] ) );
       }
       if ( isset( $_POST['billing_postcode'] ) ) {
              // aktualizujeme PSČ
              update_user_meta( $customer_id, 'billing_postcode', sanitize_text_field( $_POST['billing_postcode'] ) );
       } 
       if ( isset( $_POST['billing_company'] ) ) {
              // aktualizujeme název firmy
              update_user_meta( $customer_id, 'billing_company', sanitize_text_field( $_POST['billing_company'] ) );
       }
       if ( isset( $_POST['billing_ic'] ) ) {
              // aktualizujeme IČ
              update_user_meta( $customer_id, 'billing_ic', sanitize_text_field( $_POST['billing_ic'] ) );
       }
       if ( isset( $_POST['billing_dic'] ) ) {
              // aktualizujeme DIČ
              update_user_meta( $customer_id, 'billing_dic', sanitize_text_field( $_POST['billing_dic'] ) );
       }                                         
}
add_action( 'woocommerce_created_customer', 'wooc_save_extra_register_fields' );