woocommerce-set-minimum-quantity-per-product-before-checking-out-incomplete.php

<?php

// Set minimum quantity per product before checking out

add_action( 'woocommerce_check_cart_items', 'spyr_set_min_qty_per_product' );
function spyr_set_min_qty_per_product() {

	// Only run in the Cart or Checkout pages
	if( is_cart() || is_checkout() ) {	
		global $woocommerce;

		// Product Id and Min. Quantities per Product
		$product_min_qty = array( 
			array( 'id' => 20, 'min' => 100 ),
			array( 'id' => 30, 'min' => 100 ),
			array( 'id' => 40, 'min' => 100 ),
			array( 'id' => 50, 'min' => 100 ),
		);

		// Will increment
		$i = 0;
		// Will hold information about products that have not
		// met the minimum order quantity
		$bad_products = array();

		// Loop through the products in the Cart
		foreach( $woocommerce->cart->cart_contents as $product_in_cart ) {

			// Loop through our minimum order quantities per product
			foreach( $product_min_qty as $product_to_test ) {

				// If we can match the product ID to the ID set on the minimum required array
				if( $product_to_test['id'] == $product_in_cart['product_id'] ) {

					// If the quantity required is less than than the quantity in the cart now
					if( $product_in_cart['quantity'] < $product_to_test['min'] ) { // Get the product ID $bad_products[$i]['id'] = $product_in_cart['product_id']; // Get the Product quantity already in the cart for this product $bad_products[$i]['in_cart'] = $product_in_cart['quantity']; // Get the minimum required for this product $bad_products[$i]['min_req'] = $product_to_test['min']; } } } // Increment $i $i++; } // Time to build our error message to inform the customer // About the minimum quantity per order. if( is_array( $bad_products) && count( $bad_products ) > 1 ) {

			// Lets begin building our message
			$message = '<strong>A minimum quantity per product has not been met.</strong>';
			foreach( $bad_products as $bad_product ) {
				// Append to the current message
				$message .= get_the_title( $bad_product['id'] ) .' requires a minimum quantity of '
						 . $bad_product['min_req'] 
						 .'. You currently have: '. $bad_product['in_cart'] .'.';
			}
			wc_add_notice( $message, 'error' );
		}
	}
}
      
?>