--- uc_po.module.original	2009-02-13 12:25:11.000000000 +0100
+++ uc_po.module	2009-02-13 12:26:33.000000000 +0100
@@ -21,7 +21,7 @@
 function uc_po_menu() {
   $items = array();
 
-  
+
   $items['admin/store/orders/po'] = array(
     'title' => 'Search by PO',
     'page callback' => 'drupal_get_form',
@@ -32,6 +32,15 @@ function uc_po_menu() {
     'type' => MENU_NORMAL_ITEM,
   );
 
+  $items['admin/store/settings/po'] = array(
+    'title' => t('Purchase Order Settings'),
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('uc_po_admin'),
+    'access arguments' => array('access administration pages'),
+    'description' => t('Configure Purchase Order'),
+    'type' => MENU_NORMAL_ITEM,
+  );
+
   return $items;
 }
 
@@ -165,22 +174,26 @@ function uc_payment_method_po($op, &$arg
     // Handles receiving the data entered by the customer.
     case 'cart-process':
       if (empty($_POST['po_number'])) {
-        drupal_set_message(t('You must specify a PO number to pay by purchase order.'), 'error');
-        return FALSE;
+        $arg1->payment_details['po_number'] = "WEB ORDER";
+        return TRUE;
       }
       $arg1->payment_details['po_number'] = check_plain($_POST['po_number']);
       return TRUE;
 
     // Display the PO number on the order review page prior to submission.
     case 'cart-review':
-      $review[] = array('title' => t('PO number'), 'data' => check_plain($arg1->payment_details['po_number']));
-      return $review;
+      if (variable_get('uc_po_manual', 1) == 1) {
+        $review[] = array('title' => t('PO number'), 'data' => check_plain($arg1->payment_details['po_number']));
+        return $review;
+      }
 
     // Display the PO number in the payment order pane.
     case 'customer-view':
     case 'order-view':
-      $output = t('PO number: !po_number', array('!po_number' => check_plain($arg1->payment_details['po_number'])));
-      return $output;
+      if (variable_get('uc_po_manual', 1) == 1) {
+        $output = t('PO number: !po_number', array('!po_number' => check_plain($arg1->payment_details['po_number'])));
+        return $output;
+      }
 
     // Displayed on the order edit screen so admin can update the PO number.
     case 'order-details':
@@ -189,8 +202,10 @@ function uc_payment_method_po($op, &$arg
 
     // Update the PO number when the order form is submitted.
     case 'edit-process':
-      $changes['payment_details']['po_number'] = check_plain($_POST['po_number']);
-      return $changes;
+      if (variable_get('uc_po_manual', 1) == 1) {
+        $changes['payment_details']['po_number'] = check_plain($_POST['po_number']);
+        return $changes;
+      }
 
     // Add a few PO related fields to the payment methods settings form.
     case 'settings':
@@ -210,70 +225,97 @@ function uc_payment_method_po($op, &$arg
 
 // Returns the form for users to enter or adjust a PO number.
 function uc_payment_method_po_form($order) {
-  $form['po_instructions'] = array(
-    '#value' => '<div class="payment-instructions">'
-              . variable_get('uc_po_instructions', uc_get_message('po_instructions'))
-               .'</div>',
-  );
-  $form['po_number'] = array(
-    '#type' => 'textfield',
-    '#title' => t('PO number'),
-    '#default_value' => $order->payment_details['po_number'],
-    '#size' => 32,
-  );
-
-  return $form;
+  if (variable_get('uc_po_manual', 1) == 1) {
+    $form['po_instructions'] = array(
+      '#value' => '<div class="payment-instructions">'
+                . variable_get('uc_po_instructions', uc_get_message('po_instructions'))
+                .'</div>',
+    );
+    $form['po_number'] = array(
+      '#type' => 'textfield',
+      '#title' => t('PO number'),
+      '#default_value' => $order->payment_details['po_number'],
+      '#size' => 32,
+    );
+    return  $form;
+  }
 }
 
 // Themes the PO entry form to be in a table with the appropriate CSS rules for
 // checkout and for the order edit screen.
 function theme_uc_payment_method_po_form($form) {
-  $form['po_number']['#title'] = '';
-  $table = 'order-edit-table';
-  $label = 'oet-label';
-
-  if (arg(0) !== 'admin') {
-    $output = drupal_render($form['po_instructions']);
-    $table = 'inline-pane-table';
-    $label = 'field-label';
-  }
-  $output .= '<table class="'. $table .'"><tr><td class="'. $label .'">'
-           . t('PO number') .':</td><td>'. drupal_render($form['po_number'])
+  if (variable_get('uc_po_manual', 1) == 1) {
+    $form['po_number']['#title'] = '';
+    $table = 'order-edit-table';
+    $label = 'oet-label';
+
+    if (arg(0) !== 'admin') {
+      $output = drupal_render($form['po_instructions']);
+      $table = 'inline-pane-table';
+      $label = 'field-label';
+    }
+
+    
+    $output .= '<table class="'. $table .'"><tr><td class="'. $label .'">'
+            . t('PO number') .':</td><td>'. drupal_render($form['po_number'])
             .'</td></tr></table>';
 
-  return $output;
+    return $output;
+  }
 }
 
 // Allow administrators to search orders by PO number.
 function uc_po_search_form() {
-  $po_number = arg(4);
 
-  if (!empty($po_number)) {
-    $result = db_query("SELECT * FROM {uc_payment_po} WHERE po_number LIKE '%%%s%%'", $po_number);
-    while ($order = db_fetch_object($result)) {
-      $rows[] = array(l($order->order_id, 'admin/store/orders/'. $order->order_id), $order->po_number);
+  if (variable_get('uc_po_manual', 1) == 1) {
+    $po_number = arg(4);
+
+    if (!empty($po_number)) {
+      $result = db_query("SELECT * FROM {uc_payment_po} WHERE po_number LIKE '%%%s%%'", $po_number);
+      while ($order = db_fetch_object($result)) {
+        $rows[] = array(l($order->order_id, 'admin/store/orders/'. $order->order_id), $order->po_number);
+      }
+      $header = array(t('Order ID'), t('PO number'));
+      $form['results'] = array(
+        '#value' => '<div><br />'. t('Search returned the following results:')
+                  .'</div><div><br />'. theme('table', $header, $rows) .'</div>',
+      );
     }
-    $header = array(t('Order ID'), t('PO number'));
-    $form['results'] = array(
-      '#value' => '<div><br />'. t('Search returned the following results:')
-                 .'</div><div><br />'. theme('table', $header, $rows) .'</div>',
-    );
-  }
 
-  $form['po_number'] = array(
-    '#type' => 'textfield',
-    '#title' => t('PO number'),
-    '#default_value' => $po_number,
-    '#size' => 32,
-  );
-  $form['submit'] = array(
-    '#type' => 'submit',
-    '#value' => t('Submit'),
-  );
+    $form['po_number'] = array(
+      '#type' => 'textfield',
+      '#title' => t('PO number'),
+      '#default_value' => $po_number,
+      '#size' => 32,
+    );
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => t('Submit'),
+    );
 
-  return $form;
+    return $form;
+  } else {
+    $form['results'] = array(
+        '#value' => '<div>'. t('Product Order number has been disabled.') . '</div>',
+      );
+    return $form;
+  }
 }
 
 function uc_po_search_form_submit($form, &$form_state) {
   return 'admin/store/orders/po/'. check_plain($form_state['values']['po_number']);
 }
+
+// PO Settings page: used for enable/disable the PO field during the purchase workflow.
+// WARNING: when disabled, the po_number field is set to "WEB ORDER".
+function uc_po_admin(){
+    $form['uc_po_manual'] = array(
+    '#type' => 'checkbox',
+    '#title' => t('Enable manual Purchase Order input'),
+    '#default_value' => variable_get('uc_po_manual', 1),
+    '#description' => t("Enabling manual PO, allow customers to specify the Purchase Order code. When disabled it will be setted automatically."),
+    '#required' => TRUE,
+  );
+
+  return system_settings_form($form);
+}