Snippet to change estimate delivery based on variable product (backorder and instock).

functions.php

/**
 * Snippet to change estimate delivery based on variable product (backorder and instock).
 * Created at : 19 Jan 2019
 * PluginHive Plugins : https://www.pluginhive.com/plugins/
 */

add_filter( 'woocommerce_get_availability', 'woocommerce_get_availability',12,2 );
function woocommerce_get_availability( $stock_arr ,$item) {
	if( empty($item) ){
			global $product;
			if( ! is_object($product) ) {
				global $post;
				$product = wc_get_product($post->ID);
			}
			$item = $product;
		}
	$date_format='d/m/Y';  // should same as date format in plugin settings
	$backorder_available=array(
		'370' => '21/01/2019',  // variable id => no of days for backorder
		'61' => '20/12/2018'
	);
	$instock_available=array(
		'370' => '21/01/2019',  // variable id => no of days for instock
		'61' => '20/12/2018'
	);
	$product_id=$item->get_id();
	if(!empty($stock_arr) && !empty($stock_arr['availability']) && ($item->get_stock_status()=='onbackorder'|| $item->get_stock_status()=='instock') )
	{
		$display_text="Estimated delivery by"; // should be same as Product Page Text in plugin settings
		$text_arr=explode($display_text, $stock_arr['availability']);
		$availability=$stock_arr['availability'];
		if(isset($text_arr[1]))
		{
			$product_page_sample_text	= get_option('wf_estimated_delivery_product_page_text_simple');
			$product_page_sample_text	= !empty( $product_page_sample_text ) ? $product_page_sample_text : '<p style="color:green;font-size:small">'.__( 'Estimated delivery by', 'wf_estimated_delivery' ).' [date]</p>';
			
			$product_page_text_range	 = get_option('wf_estimated_delivery_product_page_text_range');
			$product_page_text_range	 = !empty( $product_page_text_range ) ? $product_page_text_range : '<p style="color:green;font-size:small">'.__( 'Estimated delivery by','wf_estimated_delivery' ).' [date_1] - [date_2]</p>';
			
			$product_page_sample_text	= apply_filters( 'wpml_translate_single_string', $product_page_sample_text, 'wf_estimated_delivery', 'product_page_simple_text');
			$product_page_text_range	= apply_filters( 'wpml_translate_single_string', $product_page_text_range, 'wf_estimated_delivery', 'product_page_range_text');
			if($item->get_stock_status()=='instock')
			{
				if(!isset($instock_available[$product_id]))
				{
					return $stock_arr;
				}
				$available_within=date_create_from_format('d/m/Y',$instock_available[$product_id]); 
			}
			else
			{
				if(!isset($backorder_available[$product_id]))
				{
					return $stock_arr;
				}
				$available_within=date_create_from_format('d/m/Y',$backorder_available[$product_id]); 
			}
			

			$current_time = current_time('Y m d H:i:s');
			$today_wp_date = date_create_from_format( 'Y m d H:i:s', $current_time);
			$today_wp_date_seconds = $today_wp_date->format('U');
			$available_within 	=  ceil( ($available_within->format('U') - $today_wp_date_seconds ) / 86400 );

			$date_array=explode('</p>', $text_arr[1]);
			$date_arr=explode('-', $date_array[0]);
			if(!isset($date_arr[1]))    // for simple range
			{
	    		$date= date_create_from_format( $date_format ,trim($date_arr[0]));
	    		if( is_a($date, 'DateTime') ) {
			    		$date->modify("+$available_within days");
					$true=1;
					$wf_workdays=get_option( 'wf_estimated_delivery_operation_days' );
					while($true==1)
					{
						if(in_array( strtolower(date_format($date,'D')), $wf_workdays ))
						{
							$true=0;
						}
						else
						{
							$date->modify( "1 day" );
						}
					}
			    		$date=$date->format($date_format);
						$availability = str_replace('[date]', $date , $product_page_sample_text );
						$old_text=str_replace('[date]', trim($date_arr[0]) , $product_page_sample_text );
	    		}
			}
			$old_availability=explode($old_text,$stock_arr['availability']);
			$stock_arr['availability']=$old_availability[0].$availability;
		}
	}
	return $stock_arr;
}



add_filter( 'xa_estimated_delivery_cart_checkout_page_html_formatted_date', 'xa_estimated_delivery_cart_checkout_page_html_formatted_date',10,2 );
function xa_estimated_delivery_cart_checkout_page_html_formatted_date( $text, $test  ) {
	global $woocommerce;

	$date_format='d/m/Y';  // should same as date format in plugin settings
	$backorder_available=array(
		'370' => '21/01/2019',  // variable id => no of days for backorder
		'61' => '20/12/2018'
	);
	$instock_available=array(
		'370' => '21/01/2019',  // variable id => no of days for instock
		'61' => '20/12/2018'
	);
    $items = $woocommerce->cart->get_cart();
    	$max_count=0;
        foreach($items as $item => $values) { 
			$product_id=$values['data']->get_id();
        	if($values['data']->get_stock_status()=='onbackorder' || $values['data']->get_stock_status()=='instock' )
        	{
        		if($values['data']->get_stock_status()=='instock')
				{
					if(!isset($instock_available[$product_id]))
					{
						return $text;
					}
					$available_within=date_create_from_format('d/m/Y',$instock_available[$product_id]); 
				}
				else
				{
					if(!isset($backorder_available[$product_id]))
					{
						return $text;
					}
					$available_within=date_create_from_format('d/m/Y',$backorder_available[$product_id]); 
				}


				$current_time = current_time('Y m d H:i:s');
				$today_wp_date = date_create_from_format( 'Y m d H:i:s', $current_time);
				$today_wp_date_seconds = $today_wp_date->format('U');
				$available_within 	=  ceil( ($available_within->format('U') - $today_wp_date_seconds ) / 86400 );
				if($max_count<$available_within)
				{
					$max_count=$available_within;
				}
        	}
        } 
	$display_text 	= "Estimated Delivery";		// Text for Estimated delivery


	$text_array 	= explode( '<td data-title="'.$display_text.'" >', $text ); //cart
	if(!isset($text_array[1])) // check text format is simple 
	{
		$text_array 	= explode( '<td data-title="'.$display_text.'">', $text ); //checkout  
		if(!isset($text_array[1])) // check text format is simple 
		{
			return $text;
		}
	}
	$text_array 	= explode( '</td></tr>', $text_array[1] );
	$prev_date_arr 	= explode( '-', $text_array[0] );				//Contains the date in case of date range

	if(!isset($prev_date_arr[1])) { 

		$max_date 	= date_create_from_format( $date_format, trim($prev_date_arr[0]) );

		$max_date->modify( "$max_count day" );
		$true=1;
		$wf_workdays=get_option( 'wf_estimated_delivery_operation_days' );
		while($true==1)
		{
			if(in_array( strtolower(date_format($max_date,'D')), $wf_workdays ))
			{
				$true=0;
			}
			else
			{
				$max_date->modify( "1 day" );
			}
		}
		$text = '<tr class="shipping"><th> '.$display_text.'</th><td data-title="'.$display_text.'"> '.$max_date->format($date_format) .'</td></tr>';
	}

	return $text;
}
// Adjustment on Thank you page.
add_filter( 'xa_estimated_delivery_thank_you_page_html_formatted_date', 'xa_estimated_delivery_thank_you_page_html_formatted_date', 10, 2 );

function xa_estimated_delivery_thank_you_page_html_formatted_date( $text, $test ) {
	global $woocommerce;
	$date_format='d/m/Y';  // should same as date format in plugin settings
	$backorder_available=array(
		'370' => '21/01/2019',  // variable id => no of days for backorder
		'61' => '20/12/2018'
	);
	$instock_available=array(
		'370' => '21/01/2019',  // variable id => no of days for instock
		'61' => '20/12/2018'
	);
    $items = $woocommerce->cart->get_cart();
    	$max_count=0;
        foreach($items as $item => $values) { 
			$product_id=$values['data']->get_id();
        	if($values['data']->get_stock_status()=='onbackorder' || $values['data']->get_stock_status()=='instock' )
        	{
        		if($values['data']->get_stock_status()=='instock')
				{
					if(!isset($instock_available[$product_id]))
					{
						return $text;
					}
					$available_within=date_create_from_format('d/m/Y',$instock_available[$product_id]); 
				}
				else
				{
					if(!isset($backorder_available[$product_id]))
					{
						return $text;
					}
					$available_within=date_create_from_format('d/m/Y',$backorder_available[$product_id]); 
				}

				$current_time = current_time('Y m d H:i:s');
				$today_wp_date = date_create_from_format( 'Y m d H:i:s', $current_time);
				$today_wp_date_seconds = $today_wp_date->format('U');
				$available_within 	=  ceil( ($available_within->format('U') - $today_wp_date_seconds ) / 86400 );
				if($max_count<$available_within)
				{
					$max_count=$available_within;
				}
        	}
        } 
	$display_text 	= "Estimated Delivery";		// Text for Estimated delivery


	$text_array 	= explode( '-', trim( $text) );

	if(!isset($text_array[1])) { 

		$max_date 	= date_create_from_format( $date_format, trim($text_array[0]) );

		$max_date->modify( "$max_count day" );
		$true=1;
		$wf_workdays=get_option( 'wf_estimated_delivery_operation_days' );
		while($true==1)
		{
			if(in_array( strtolower(date_format($max_date,'D')), $wf_workdays ))
			{
				$true=0;
			}
			else
			{
				$max_date->modify( "1 day" );
			}
		}
		$text = $max_date->format($date_format);
	}

	return $text;
}