From 8e810273ebc14f2e8f08360a05047bb7dd02c232 Mon Sep 17 00:00:00 2001
From: Michael Stenta <mike@mstenta.net>
Date: Wed, 4 Apr 2018 10:50:46 -0400
Subject: [PATCH] Create custom Views filter handler for log owner (based on
 taxonomy term reference filter).

---
 .../farm/farm_fields/farm_fields.features.inc |   7 +
 modules/farm/farm_fields/farm_fields.info     |   1 +
 .../farm/farm_fields/farm_fields.views.inc    |  22 +++
 .../farm_fields_handler_filter_log_owner.inc  | 165 ++++++++++++++++++
 4 files changed, 195 insertions(+)
 create mode 100644 modules/farm/farm_fields/farm_fields.views.inc
 create mode 100644 modules/farm/farm_fields/views/handlers/farm_fields_handler_filter_log_owner.inc

diff --git a/modules/farm/farm_fields/farm_fields.features.inc b/modules/farm/farm_fields/farm_fields.features.inc
index 1dbbb2232..e5f84d9d9 100644
--- a/modules/farm/farm_fields/farm_fields.features.inc
+++ b/modules/farm/farm_fields/farm_fields.features.inc
@@ -12,3 +12,10 @@ function farm_fields_ctools_plugin_api($module = NULL, $api = NULL) {
     return array("version" => "1");
   }
 }
+
+/**
+ * Implements hook_views_api().
+ */
+function farm_fields_views_api($module = NULL, $api = NULL) {
+  return array("api" => "3.0");
+}
diff --git a/modules/farm/farm_fields/farm_fields.info b/modules/farm/farm_fields/farm_fields.info
index 16e737f39..1dd1e678d 100644
--- a/modules/farm/farm_fields/farm_fields.info
+++ b/modules/farm/farm_fields/farm_fields.info
@@ -31,3 +31,4 @@ features[field_base][] = field_farm_people
 features[filter][] = farm_format
 features[taxonomy][] = farm_log_categories
 features[variable][] = pathauto_taxonomy_term_farm_log_categories_pattern
+files[] = views/handlers/farm_fields_handler_filter_log_owner.inc
diff --git a/modules/farm/farm_fields/farm_fields.views.inc b/modules/farm/farm_fields/farm_fields.views.inc
new file mode 100644
index 000000000..5c6d6a393
--- /dev/null
+++ b/modules/farm/farm_fields/farm_fields.views.inc
@@ -0,0 +1,22 @@
+<?php
+
+/**
+ * @file
+ * Farm fields views data.
+ */
+
+/**
+ * Implements hook_field_views_data_alter().
+ */
+function farm_fields_field_views_data_alter(&$result, $field, $module) {
+
+  // Replace the filter handler for field_farm_log_owner fields so that we can
+  // expose a select list of user options.
+  $owner_field = 'field_farm_log_owner';
+  if ($field['field_name'] == $owner_field) {
+    if (!empty($result['field_data_' . $owner_field][$owner_field . '_target_id']['filter'])) {
+      $filter = &$result['field_data_' . $owner_field][$owner_field . '_target_id']['filter'];
+      $filter['handler'] = 'farm_fields_handler_filter_log_owner';
+    }
+  }
+}
diff --git a/modules/farm/farm_fields/views/handlers/farm_fields_handler_filter_log_owner.inc b/modules/farm/farm_fields/views/handlers/farm_fields_handler_filter_log_owner.inc
new file mode 100644
index 000000000..24bb7eb47
--- /dev/null
+++ b/modules/farm/farm_fields/views/handlers/farm_fields_handler_filter_log_owner.inc
@@ -0,0 +1,165 @@
+<?php
+
+/**
+ * @file
+ * Definition of farm_fields_handler_filter_log_owner.
+ */
+
+/**
+ * Provide an exposed filter that presents user options in a select list.
+ *
+ * This is based heavily on the code in views_handler_filter_term_node_tid,
+ * modified to simplify and remove unneeded options.
+ *
+ * @ingroup views_filter_handlers
+ */
+class farm_fields_handler_filter_log_owner extends views_handler_filter_many_to_one {
+
+  // Stores the exposed input for this filter.
+  var $validated_exposed_input = NULL;
+
+  function value_form(&$form, &$form_state) {
+    $options = array();
+
+    // Select all active users.
+    $query = db_select('users', 'u');
+    $query->fields('u');
+    $query->condition('u.status', 1);
+    $query->orderby('u.name');
+
+    // Add a custom tag to the query so other modules can modify.
+    $query->addTag('farm_log_owner');
+
+    // Execute the query.
+    $result = $query->execute();
+
+    $uids = array();
+    foreach ($result as $user) {
+      $uids[] = $user->uid;
+    }
+    $entities = user_load_multiple($uids);
+    foreach ($entities as $entity_user) {
+      $options[$entity_user->uid] = entity_label('user', $entity_user);
+    }
+
+    $default_value = (array) $this->value;
+
+    if (!empty($form_state['exposed'])) {
+      $identifier = $this->options['expose']['identifier'];
+
+      if (!empty($this->options['expose']['reduce'])) {
+        $options = $this->reduce_value_options($options);
+
+        if (!empty($this->options['expose']['multiple']) && empty($this->options['expose']['required'])) {
+          $default_value = array();
+        }
+      }
+
+      if (empty($this->options['expose']['multiple'])) {
+        if (empty($this->options['expose']['required']) && (empty($default_value) || !empty($this->options['expose']['reduce']))) {
+          $default_value = 'All';
+        }
+        elseif (empty($default_value)) {
+          $keys = array_keys($options);
+          $default_value = array_shift($keys);
+        }
+        // Due to #1464174 there is a chance that array('') was saved in the admin ui.
+        // Let's choose a safe default value.
+        elseif ($default_value == array('')) {
+          $default_value = 'All';
+        }
+        else {
+          $copy = $default_value;
+          $default_value = array_shift($copy);
+        }
+      }
+    }
+    $form['value'] = array(
+      '#type' => 'select',
+      '#title' => t('Select people'),
+      '#multiple' => TRUE,
+      '#options' => $options,
+      '#size' => min(9, count($options)),
+      '#default_value' => $default_value,
+    );
+
+    if (!empty($form_state['exposed']) && isset($identifier) && !isset($form_state['input'][$identifier])) {
+      $form_state['input'][$identifier] = $default_value;
+    }
+
+    if (empty($form_state['exposed'])) {
+      // Retain the helper option
+      $this->helper->options_form($form, $form_state);
+
+      // Show help text if not exposed to end users.
+      $form['value']['#description'] = t('Leave blank for all. Otherwise, the first selected person will be the default instead of "Any".');
+    }
+  }
+
+  function accept_exposed_input($input) {
+    if (empty($this->options['exposed'])) {
+      return TRUE;
+    }
+
+    // We need to know the operator, which is normally set in
+    // views_handler_filter::accept_exposed_input(), before we actually call
+    // the parent version of ourselves.
+    if (!empty($this->options['expose']['use_operator']) && !empty($this->options['expose']['operator_id']) && isset($input[$this->options['expose']['operator_id']])) {
+      $this->operator = $input[$this->options['expose']['operator_id']];
+    }
+
+    // If view is an attachment and is inheriting exposed filters, then assume
+    // exposed input has already been validated
+    if (!empty($this->view->is_attachment) && $this->view->display_handler->uses_exposed()) {
+      $this->validated_exposed_input = (array) $this->view->exposed_raw_input[$this->options['expose']['identifier']];
+    }
+
+    // If we're checking for EMPTY or NOT, we don't need any input, and we can
+    // say that our input conditions are met by just having the right operator.
+    if ($this->operator == 'empty' || $this->operator == 'not empty') {
+      return TRUE;
+    }
+
+    // If it's non-required and there's no value don't bother filtering.
+    if (!$this->options['expose']['required'] && empty($this->validated_exposed_input)) {
+      return FALSE;
+    }
+
+    $rc = parent::accept_exposed_input($input);
+    if ($rc) {
+      // If we have previously validated input, override.
+      if (!$this->is_a_group() && isset($this->validated_exposed_input)) {
+        $this->value = $this->validated_exposed_input;
+      }
+    }
+
+    return $rc;
+  }
+
+  function exposed_validate(&$form, &$form_state) {
+    if (empty($this->options['exposed'])) {
+      return;
+    }
+
+    $identifier = $this->options['expose']['identifier'];
+
+    // Get the values from the form state.
+    if (isset($form_state['values'][$identifier]) && $form_state['values'][$identifier] != 'All') {
+      $this->validated_exposed_input = (array) $form_state['values'][$identifier];
+    }
+  }
+
+  function admin_summary() {
+    // set up $this->value_options for the parent summary
+    $this->value_options = array();
+
+    if ($this->value) {
+      $this->value = array_filter($this->value);
+      $result = user_load_multiple($this->value);
+      foreach ($result as $entity_user) {
+        $this->value_options[$entity_user->tid] = entity_label('user', $entity_user);
+      }
+    }
+    return parent::admin_summary();
+  }
+}