WooCommerce custom checkout fields

custom-checkout.php

<?php
class SolusiPress_Custom_Woo_Checkout {
	
	public function __construct() {		
		add_filter( 'woocommerce_default_address_fields', array( $this, 'woo_address_fields' ), 50, 1 );
		add_filter( 'woocommerce_checkout_fields', array( $this, 'woo_checkout_fields' ) );
        // first & last name merge
        add_filter( 'default_checkout_billing_first_name', array( $this, 'first_name_default_value' ), 10, 2 );
        add_filter( 'default_checkout_shipping_first_name', array( $this, 'first_name_default_value' ), 10, 2 );        
        add_filter( 'woocommerce_checkout_posted_data', array( $this, 'checkout_full_name_posted_data' ), 11 );		
	}
	
	public function woo_address_fields( $fields ) {                       
		unset( $fields['company'] );        
		unset( $fields['postcode'] );

		// merge first name & last name
		$fields['first_name']['class'][0] = 'form-row-wide';
		$fields['first_name']['label'] = 'Full Name';
    	unset( $fields['last_name'] );   
      	
		// swap field position
	    $fields['address_1']['priority'] = 60;	    
        $fields['address_2']['priority'] = 50;           
	    
		//unset($fields['address_2']);  # uncomment to remove address_2
	    
		return $fields;
	}
	
	public function woo_checkout_fields( $fields ) {
		/* remove email or phone */
		unset( $fields['billing']['billing_phone'] );
		//unset( $fields['billing']['billing_email'] );
	    return $fields;
	}
	
    public function first_name_default_value( $value, $input ) {      
		$checkout = WC_Checkout::instance();
		$ln = $checkout->get_value( str_replace( 'first', 'last', $input ) );
		return trim( $value . ' ' . $ln );        
        return $value;
    }
    
    private function get_last_name( $full_name ) {
        unset( $full_name[0] );
        return implode( ' ', $full_name );
    }
    
    function checkout_full_name_posted_data( $data ) {        
		if( isset( $data['billing_first_name'] ) ) {
			$full_name = explode( ' ', $data['billing_first_name'] );     
			$data['billing_first_name'] = $full_name[0];
			$data['billing_last_name'] = $this->get_last_name( $full_name );
		}
		if( isset( $data['shipping_first_name'] ) ) {
			$full_name = explode( ' ', $data['shipping_first_name'] ); 
			$data['shipping_first_name'] = $full_name[0];
			$data['shipping_last_name'] = $this->get_last_name( $full_name );
		}
        return $data;
    }
	
}

new SolusiPress_Custom_Woo_Checkout();

snippets.php

<?php
	public function woo_address_fields( $fields ) {                       
		unset( $fields['company'] );        
		unset( $fields['postcode'] );

		// merge first name & last name
		$fields['first_name']['class'][0] = 'form-row-wide';
		$fields['first_name']['label'] = 'Full Name';
    	unset( $fields['last_name'] );   
      	
		// swap field position
	    $fields['address_1']['priority'] = 60;	    
        $fields['address_2']['priority'] = 50;           
	    
		//unset($fields['address_2']);  # uncomment to remove address_2
	    
		return $fields;
	}
	
	public function woo_checkout_fields( $fields ) {
		/* remove email or phone */
		unset( $fields['billing']['billing_phone'] );
		//unset( $fields['billing']['billing_email'] );
	    return $fields;
	}