<?php

/**
 * @file
 * Mailchimp module.
 */

define('MAILCHIMP_LISTTYPE_REQUIRED', 'required');
define('MAILCHIMP_LISTTYPE_OPTIN', 'optin');
define('MAILCHIMP_LISTTYPE_OPTOUT', 'optout');
define('MAILCHIMP_USERSTATUS_PENDING', 'pending');
define('MAILCHIMP_USERSTATUS_CURRENT', 'current');

/**
 * Implementation of hook_user
 *
 * Required lists are updated on insert, update, and delete.
 * The list form fields are added to the registration and profile forms
 */
function mailchimp_user($op, &$edit, &$account, $category = NULL) {
  // include the form in the user registration if any applicable newsletters
  if ($op == 'register' && variable_get('mailchimp_user_register', FALSE)){
    $account->roles = array(2 => 'authenticated');
    $lists = _mailchimp_get_available_lists($account);
    if (!empty($lists) && $q = _mailchimp_get_api_object()) {

      // wrap in a fieldset
      $form['mailchimp_list_forms'] = array(
        '#type' => 'fieldset',
        '#title' => t(variable_get('mailchimp_user_settings_title', 'Newsletter Subscriptions')),
      );

      // container for the list objects we'll need on form submission
      $form['mailchimp_lists'] = array(
        '#type'   => 'value'
      );
      
      foreach ($lists as $list) {
        if ($list->listtype !== MAILCHIMP_LISTTYPE_REQUIRED) {
          mailchimp_auth_newsletter_form($form['mailchimp_list_forms'], $list, NULL, $q);
          $form['mailchimp_lists']['#value'][] = $list;
        }
      }

      return $form;
    }
  }
  
  if ($op == 'insert' && variable_get('mailchimp_user_register', FALSE) && $q = _mailchimp_get_api_object()) {
    foreach ((array)$edit['mailchimp_lists'] as $list) {
      // is the checkbox for the newsletter selected?
      if (isset($edit['mailchimp_list_' . $list->id] ) && $edit['mailchimp_list_' . $list->id] ) {
        $merge_vars = _mailchimp_load_user_list_mergevars($account->uid, $list->id, $q->listMergeVars($list->id));
  
        // include interest groups
        if (isset($edit['interest_groups_' . $list->id]) && is_array($edit['interest_groups_' . $list->id])) {
          foreach($edit['interest_groups_' . $list->id] as $key => $group) {
            $merge_vars['GROUPINGS'][] = array('id' => $key, 'groups' => _mailchimp_implode_interest_groups($group));
          }
        }
  
        $ret = _mailchimp_subscribe_user($list, $account->mail, $merge_vars, TRUE, $q);
  
        if (!$ret) {
          watchdog('mailchimp', 'MCAPI Error: %errormsg', array('%errormsg' => $q->errorMessage), WATCHDOG_ERROR);
        }        
      }
    }    
  }

  if (in_array($op, array('insert', 'delete', 'update', 'after_update')) && $q = _mailchimp_get_api_object()) {
    foreach ((array)_mailchimp_get_required_lists() as $list) {
      $action_taken = FALSE;
      switch ($op) {
      // delete a user from MC list
        case "delete":
          db_query('DELETE FROM {mailchimp_user} WHERE uid = %d', $account->uid);
          $ret = _mailchimp_unsubscribe_user($list, $account->mail, FALSE, $q);
          $action_taken = TRUE;
          break;
        case 'update';
          $_SESSION['prev_email'] = $account->mail;
          break;
        // insert or update a user to/in a MC list
        case 'insert':
        case 'after_update':
          // don't repeat if already managing via cron
          if (!variable_get('mailchimp_cron', FALSE) ) {
            $action_taken = TRUE;

            // determine if a user is allowed in a given list
            $is_allowed = FALSE;
            $roles = empty($edit['roles']) ? $account->roles : $edit['roles'];
            foreach($list->roles as $key=>$value){
              if(array_key_exists($key, $roles)){
                $is_allowed = TRUE;
                break;
              }
            }

            // they are allowed, update or subscribe
            if($is_allowed  && $account->status == 1){
              $userinfo = _mailchimp_load_user_list_mergevars($account->uid, $list->id, $q->listMergeVars($list->id));
              $userinfo['EMAIL'] = $edit['mail'];
              $ret = _mailchimp_subscribe_user($list, $_SESSION['prev_email'], $userinfo, FALSE, $q);
              unset($_SESSION['prev_email']);
            }
            // remove from list
            else{
              $ret = _mailchimp_unsubscribe_user($list, $account->mail, FALSE, $q);
            }
          }
          else {
            // They don't *really* need to go in the queue unless they just changed their prefs.
            if ($op == 'insert') {
              db_query("INSERT INTO {mailchimp_user} (uid, status) VALUES (%d, '%s')", $account->uid, MAILCHIMP_USERSTATUS_PENDING);
            }
            else {
              db_query("UPDATE {mailchimp_user} SET status = '%s' WHERE uid = %d", MAILCHIMP_USERSTATUS_PENDING, $account->uid);
            }
          }
          break;
      }

      if($action_taken){
        if ($ret) {
          watchdog('mailchimp', 'MailChimp: %email updated in list %list on action %action',
              array('%email' => $account->mail, '%list' => $list->name, '%action' => $op), WATCHDOG_NOTICE);
        }
        else {
          watchdog('mailchimp', 'MCAPI Error: %errormsg', array('%errormsg' => $q->errorMessage), WATCHDOG_ERROR);
        }
      }
    }
  }
}

/**
 * Maichimp authenticated user subscription form.
 */
function mailchimp_subscribe_auth_form($form_state, $account, $standalone = TRUE, $list = NULL) {
  $form = array();

  if ($q = _mailchimp_get_api_object()) {
    if ($account->uid) {
      $form['uid'] = array(
        '#type' => 'hidden',
        '#value' => $account->uid
      );
    }
    else {
      // user registration or admin creating new user
      $account->roles = array(2 => 'authenticated');
    }
    
    $lists = array();
    if (empty($list)) {
      $lists = _mailchimp_get_available_lists($account);
    } else {
      $lists[$list->id] = $list;
    }

    foreach ($lists as $list) {
      mailchimp_auth_newsletter_form($form, $list, $account, $q);
    }

    $form['lists'] = array(
      '#type'   => 'value',
      '#value'  => $lists
    );

    if ($standalone){
      $form['submit'] = array(
        '#type' => 'submit',
        '#value' => t('save settings'),
        '#weight' => 100
      );

      $form['#submit'][] = 'mailchimp_subscribe_auth_form_submit';
    }
  }

  return $form;
}

/**
 * Implementation of hook_forms().
 */
function mailchimp_forms($form_id, $args) {
  // have all instances of mailchimp_subscribe_auth_form and 
  // mailchimp_subscribe_auth_form map to a single form factory. Needed in 
  // case more than one block on a single page.
  if (strpos($form_id, 'mailchimp_subscribe_auth_form') !== FALSE) {
    $forms[$form_id] = array(
      'callback' => 'mailchimp_subscribe_auth_form',
    );
    return $forms;
  }
  else if (strpos($form_id, 'mailchimp_subscribe_anon_form') !== FALSE) {
    $forms[$form_id] = array(
      'callback' => 'mailchimp_subscribe_anon_form',
    );
    return $forms;
  }
}

/**
 * Called from mailchimp_subscribe_auth_form() and embeds the form elements for 
 * a single newseltter.
 *
 * @param string $form 
 * @param string $list 
 * @param string $account 
 * @param string $q 
 */
function mailchimp_auth_newsletter_form(&$form, $list, $account, $q) {
  $is_subscribed = FALSE;
  $member_interests = array();

  // ignore required lists, handled by hook_user
  if ($list->listtype !== MAILCHIMP_LISTTYPE_REQUIRED) {
    if ($account && $account->uid) {
      $memberinfo = $q->listMemberInfo($list->id, $account->mail);
      $is_subscribed = $memberinfo['status'] == 'subscribed';
      $member_interests = isset($memberinfo['merges']['GROUPINGS']) ? $memberinfo['merges']['GROUPINGS'] : array();
      $default_value = $is_subscribed;
    }
    else {
      $default_value = $is_subscribed = $list->listtype == MAILCHIMP_LISTTYPE_OPTOUT ? TRUE : FALSE;
    }

    // wrap in a div
    $form['wrapper'. $list->id] = array(
      '#prefix' => '<div class="mailchimp-newsletter-wrapper">',
      '#suffix' => '</div>',
    );

    $form['wrapper'. $list->id]['mailchimp_list_'. $list->id] = array(
        '#type'           => 'checkbox',
        '#title'          => ($list->label) ? t($list->label) : t('Subscribe to the @newsletter newsletter', array('@newsletter' => $list->name)),
        '#default_value'  => $default_value,
        '#description'    => t($list->description),
        '#attributes'     => array('class' => 'mailchimp-newsletter-checkbox-' . $list->id)
    );

    // present interest groups
    if (variable_get('mailchimp_interest_groups_user_forms', FALSE)) {
      $interests = _mailchimp_interest_groups_element($q, $list->id, $member_interests, $is_subscribed);
      if (!empty($interests)) {
        $form['wrapper'. $list->id] = array_merge($form['wrapper'. $list->id], $interests);
    
        drupal_add_js('Drupal.behaviors.mailchimp = function(context) {
          $(".mailchimp-newsletter-checkbox-'. $list->id .'").click(function(){
            Drupal.toggleFieldset(".mailchimp-newsletter-interests-'. $list->id .'");
          });
        }', 'inline');
      }
    }
  }

  return $form;
}


/**
 * Submit handler to add users to lists when editing/creating a user
 */
function mailchimp_subscribe_auth_form_submit($form, &$form_state) {
  if ($q = _mailchimp_get_api_object()) {
    $account = new stdClass();
    if (!empty($form_state['values']['uid'])) {
      $account = user_load(array('uid' => $form_state['values']['uid']));
    }
    else {
      global $user;
      $account = $user;
    }

    $lists = $form_state['values']['lists'];
    foreach ($lists as $list) {
    // ignore required lists, they are handled via hook_user
      if ($list->listtype !== MAILCHIMP_LISTTYPE_REQUIRED) {
        $is_subscribed = _mailchimp_is_subscribed($list->id, $account->mail, $q);
        $ret = TRUE;
        $selected = @$form_state['values']['mailchimp_list_'. $list->id];

        // unsubscribe a subscribed user who unchecked the box when not registering
        if ($is_subscribed && !$selected && $form['#id'] != 'user-register') {
          $ret = _mailchimp_unsubscribe_user($list, $account->mail, TRUE, $q);
        }
        else if ($selected) {
        // subscribe the user if they are not previously subscribed or update existing subscriptions
          $merge_vars = _mailchimp_load_user_list_mergevars($account->uid, $list->id, $q->listMergeVars($list->id));

          // include updated email address if already subscribed
          if (!empty($form_state['values']['mail']) && $is_subscribed){
            $merge_vars['EMAIL'] = $form_state['values']['mail'];
          }

          // include interest groups
          if (isset($form_state['values']['interest_groups_' . $list->id]) && is_array($form_state['values']['interest_groups_' . $list->id])) {
            foreach($form_state['values']['interest_groups_' . $list->id] as $key => $group) {
              $merge_vars['GROUPINGS'][] = array('id' => $key, 'groups' => _mailchimp_implode_interest_groups($group));
            }
          }

          $ret = _mailchimp_subscribe_user($list, $account->mail, $merge_vars, TRUE, $q);
        }

        if (!$ret) {
          watchdog('mailchimp', 'MCAPI Error: %errormsg', array('%errormsg' => $q->errorMessage), WATCHDOG_ERROR);
        }
      }
    }
  }
}

/**
 * Implementation of hook_cron.
 *
 * Resubscribes all users to the required lists if the user has chosen to do so.
 */
function mailchimp_cron() {
  if (variable_get('mailchimp_cron', FALSE) && $q = _mailchimp_get_api_object()) {
    // grab UIDs for active users who are pending
    $sql = "SELECT mu.uid FROM {mailchimp_user} mu LEFT OUTER JOIN {users} u ON mu.uid = u.uid WHERE mu.status = '%s' AND u.status = 1";
    $result = db_query_range($sql, array(MAILCHIMP_USERSTATUS_PENDING), 0, variable_get('mailchimp_batch_limit', 100));

    if ($result) {
      $lists = _mailchimp_get_required_lists();
      foreach ($lists as $key => $list) {
        $lists[$key]->batch       = array();
        $lists[$key]->listMergeVars   = $q->listMergeVars($list->id);
        $lists[$key]->unsubscribe = array();
      }
      while ($row = db_fetch_object($result)) {
        if ($account = user_load(array('uid' => $row->uid))) {
          db_query('UPDATE {mailchimp_user} SET status = \'%s\' WHERE uid = %d', MAILCHIMP_USERSTATUS_CURRENT, $account->uid);

          foreach ((array)$lists as $key => $list) {
            $is_allowed = FALSE;
            foreach ((array)$account->roles as $rid => $info) {
              if ($list->roles[$rid]) {
                $lists[$key]->batch[] = _mailchimp_load_user_list_mergevars($row->uid, $list->id, $lists[$key]->listMergeVars);
                $is_allowed = TRUE; // user is allowed in this list
                break;
              }
            }
            
            // if a user is no longer allowed in this list, add to unsubscribe batch
            if (!$is_allowed) {
              $lists[$key]->unsubscribe[] = $account->mail;
            }              
          }
        }
        else {
          // user exists in mc_user table even though they don't have an account, remove
          db_query('DELETE FROM {mailchimp_user} WHERE uid = %d', $account->uid);
        }
      }

      $count = 0;
      $unsub_count = 0;
      foreach ($lists as $key => $list) {
        // subscribe batch
        if (count($lists[$key]->batch)) {
          $ret = $q->listBatchSubscribe($list->id, $lists[$key]->batch, FALSE, TRUE);
          if ($ret['error_count'] > 0) {
            foreach ((array)$ret['errors'] as $error) {
              watchdog('mailchimp', 'MCAPI Error: %errormsg', array('%errormsg' => $error['message']), WATCHDOG_ERROR);
            }
          }
          $count += $ret['success_count'];
        }
        
        // unsubscribe batch
        if (count($lists[$key]->unsubscribe)) {
          $ret = $q->listBatchUnsubscribe($list->id, $lists[$key]->unsubscribe, FALSE, FALSE);
          if ($ret['error_count'] > 0) {
            foreach ((array)$ret['errors'] as $error) {
              watchdog('mailchimp', 'MCAPI Error: %errormsg', array('%errormsg' => $error['message']), WATCHDOG_ERROR);
            }
          }
          $unsub_count += $ret['success_count'];
        }        
      }

      watchdog('mailchimp', 'Updated !count records in MailChimp and unsubscribed !unsub emails.', array('!count' => $count, '!unsub' => $unsub_count), WATCHDOG_NOTICE);
    }
  }
}

/**
 * Implementation of hook_menu.
 */
function mailchimp_menu() {
  $items = array();

  $items['user/%user/mailchimp'] = array(
    'page callback' => 'drupal_get_form',
    'page arguments' => array('mailchimp_subscribe_auth_form', 1),
    'title callback' => 'mailchimp_user_settings_page_title',
    'type' => MENU_LOCAL_TASK,
    'access callback' => 'mailchimp_user_edit_access',
    'access arguments' => array(1),
    'tab_parent' => 'user/%/edit',
    'weight' => 10,
  );
  $items['mailchimp/subscribe'] = array(
    'page callback' => 'mailchimp_subscribe_page',
    'title callback' => 'mailchimp_subscribe_page_title',
    'type' => MENU_NORMAL_ITEM,
    'access arguments' => array('access content'),
  );
  $items['mailchimp/unsubscribe'] = array(
    'page callback' => 'drupal_get_form',
    'page arguments' => array('mailchimp_unsubscribe_form'),
    'title callback' => 'mailchimp_unsubscribe_page_title',
    'type' => MENU_CALLBACK,
    'access callback' => TRUE,
  );
  $items['admin/settings/mailchimp'] = array(
    'title' => 'MailChimp Configuration',
    'description' => 'Manage MailChimp Settings.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('mailchimp_admin_settings'),
    'access arguments' => array('administer mailchimp'),
    'type' => MENU_NORMAL_ITEM,
    'file' => 'mailchimp.admin.inc',
  );
  $items['admin/settings/mailchimp/rebuild'] = array(
    'title' => 'Rebuild Users Table',
    'page callback' => 'mailchimp_rebuild_users',
    'access arguments' => array('administer mailchimp'),
    'weight' => 10
  );

  return $items;
}

/**
 * Access callback for the newseltter signup form from a user account.
 */
function mailchimp_user_edit_access($user){
  if(variable_get('mailchimp_user_edit', TRUE) && user_edit_access($user)){
    return TRUE;
  }
  else {
    return FALSE;
  }
}

/**
 * Implementation of hook_perm()
 */
function mailchimp_perm() {
  return array('administer mailchimp');
}

/**
 * Return all available MC lists a given user can subscribe to
 *
 * @global <type> $user
 * @return <type> page content of all available MC lists for a given user
 */
function mailchimp_subscribe_page(){
  global $user;
  $ret = '';
  if($user->uid){
    $ret = drupal_get_form('mailchimp_subscribe_auth_form', $user, TRUE, NULL);

  }
  elseif ($q = _mailchimp_get_api_object()) {
    $ret = drupal_get_form('mailchimp_subscribe_anon_form_all', $q);
  }
  return $ret;
}

/**
 * Return a form for all available MC lists
 *
 * @param <type> $form_state
 * @param <type> $list MC list object
 * @param <type> $q MC object
 * @return <type> form array
 */
function mailchimp_subscribe_anon_form_all($form_state, $q) {
  $form = array('#tree' => TRUE);
  global $user;

  $lists =_mailchimp_get_available_lists($user);
  foreach ($lists as $list) {
    $form['mailchimp_lists'][$list->id] = array(
      '#type' => 'fieldset',
      '#title' => t($list->name),
      '#description' => t($list->description),
      '#collapsible' => TRUE,
      '#collapsed' => FALSE,
    );

    _mailchimp_subscribe_anon_form($list, $q, $form['mailchimp_lists'][$list->id]);

    // for anonymous sign up forms, we want to force email to be optional
    if ($form['mailchimp_lists'][$list->id]['EMAIL']) {
      $form['mailchimp_lists'][$list->id]['EMAIL']['#required'] = FALSE;
    }
  }

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Sign Up!'),
    '#weight' => 100
  );

  $form['#submit'][] = 'mailchimp_subscribe_anon_form_submit';

  return $form;
}

/**
 * Submit handler for anonymous subscription form
 *
 * @param <type> $form_state
 * @param <type> $q - MC API object
 */
function mailchimp_subscribe_anon_form_submit($form, &$form_state) {
  if ($q = _mailchimp_get_api_object()) {
    $lists = $form_state['values']['mailchimp_lists'];
    foreach ($lists as $list) {
      if (!empty($list['EMAIL'])) {
        $success = FALSE;

        // include interest groups
        if (isset($list['interest_groups_' . $list['list']->id]) && is_array($list['interest_groups_' . $list['list']->id])) {
          foreach($list['interest_groups_' . $list['list']->id] as $key => $group) {
            $list['GROUPINGS'][] = array('id' => $key, 'groups' => _mailchimp_implode_interest_groups($group));
          }
        }

        $success = _mailchimp_subscribe_user($list['list'], $list['EMAIL'], $list, TRUE, $q);

        if ($success) {
          $msg = t(variable_get('mailchimp_subscription_success_message', 'Thank you, you have been successfully subscribed.'));        
        }
        else {
          $msg = t(variable_get('mailchimp_subscription_failure_message', 'We were unable to subscribe you at this time. Please try again later.'));        
        }

        drupal_set_message($msg);
      }
    }
  }
}

/**
 * Title callback for subscribe page
 *
 * @return <type> page title
 */
function mailchimp_subscribe_page_title() {
  return t(variable_get('mailchimp_subscribe_page_title', 'Newsletter Subscription'));
}

/**
 * Title callback for unsubscribe page
 *
 * @return <type> page title
 */
function mailchimp_unsubscribe_page_title() {
  return t(variable_get('mailchimp_unsubscribe_page_title', 'Newsletter Unsubscribe'));
}  

/**
 * Title callback for user settings page
 *
 * @return <type> page title
 */
function mailchimp_user_settings_page_title() {
  $title = t(variable_get('mailchimp_user_settings_title', 'Newsletter Subscriptions'));
  return $title;
}

/**
 * Return a form for a given MC list
 *
 * @param <type> $form_state
 * @param <type> $list MC list object
 * @param <type> $q MC object
 * @return <type> form array
 */
function mailchimp_subscribe_anon_form($form_state, $list, $q) {
  $form = array(
    '#tree' => TRUE,
    '#id' => 'mailchimp_subscribe_anon_form_' . $list->id
  );

  $form['description'] = array(
    '#value' => $list->description
  );

  _mailchimp_subscribe_anon_form($list, $q, $form['mailchimp_lists'][$list->id]);

  $form['#submit'][] = 'mailchimp_subscribe_anon_form_submit';
  
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Sign Up!'),
    '#weight' => 100
  );

  return $form;
}

/**
 * Helper function to return form elements for a single anon newsletter
 *
 * @param string $list
 * @param string $q
 * @param string $form
 * @return void
 */
function _mailchimp_subscribe_anon_form($list, $q, &$form){
  $form['list'] = array(
      '#type'   => 'value',
      '#value'  => $list
  );

  // grab any default values for authenticated users
  global $user;
  $mergevalues = NULL;
  if ($user->uid) {
    $mergevalues = _mailchimp_load_user_list_mergevars($user->uid, $list->id, $q->listMergeVars($list->id));
  }

  foreach ((array)$q->listMergeVars($list->id) as $mergevar) {
    // set the default value for merge fields if we have it
    if ($mergevalues && $mergevalues[$mergevar['tag']]) {
      $mergevar['default'] = $mergevalues[$mergevar['tag']];
    }
    $form[$mergevar['tag']] = _mailchimp_insert_drupal_form_tag($mergevar);
  }

  // present interest groups
  if (variable_get('mailchimp_interest_groups_user_forms', FALSE)) {
    $form = array_merge($form, _mailchimp_interest_groups_element($q, $list->id, array(), TRUE));
  }
}

/**
 * Helper that returns interest groups form element
 *
 * @param array $groups - list of interest groups
 * @param array $groupings - list of groups a user is in
 */
function _mailchimp_interest_groups_element($q, $list_id, $groupings = array(), $is_subscribed = FALSE) {
  $element = array();
  if ($groups = $q->listInterestGroupings($list_id)){
    $element['interest_groups_' . $list_id] = array(
      '#type' => 'fieldset',
      '#title' => t('Interest Groups'),
      '#description' => t(''),
      '#collapsible' => TRUE,
      '#collapsed' => !$is_subscribed,
      '#tree' => TRUE,
      '#attributes' => array('class' => 'mailchimp-newsletter-interests-' . $list_id),
    );

    foreach($groups as $group) {
      // ignore hidden groups
      if ($group['form_field'] != 'hidden') {
        $default = array();
        if (!empty($groupings)) {
          foreach($groupings as $grouping) {
            if ($grouping['id'] == $group['id']) {
              $default = _mailchimp_explode_interest_groups($grouping['groups']);
            }
          }
        }

        $field_type = '';
        switch ($group['form_field']) {
          case 'radio':
            $field_type = 'radios';
            break;
          case 'dropdown':
            $field_type = 'select';
            break;
          default:
            $field_type = $group['form_field'];
        }

        $options = array();
        foreach ((array)$group['groups'] as $item) {
          $options[$item['name']] = $item['name'];
        }

        $element['interest_groups_' . $list_id][$group['id']] = array(
          '#type' => $field_type,
          '#title' => t('@name', array('@name' => $group['name'])),
          '#multiple' => FALSE,
          '#options' => $options,
          '#default_value' => $default,
        );
      }
    }
  }

  return $element;
}

/**
 * Convert mailchimp form elements to Drupal Form API
 *
 * @param <type> $mergevar
 * @return <type>
 */
function _mailchimp_insert_drupal_form_tag($mergevar) {
  // Insert common FormAPI properties
  $input = array(
      '#title' => $mergevar['name'],
      '#weight' => $mergevar['order'],
      '#required' => $mergevar['req'],
      '#default_value' => $mergevar['default']
  );

  switch ($mergevar['field_type']) {
    case 'dropdown':
    // dropdown is mapped to <select> element in Drupal Form API
      $input['#type'] = 'select';

      // Creates options, we must delete array keys to have revealant information
      // on MailChimp
      foreach ($mergevar['choices'] as $choice) {
        $choices[$choice] = $choice;
      }

      $input['#options'] = $choices;
      break;
    case 'radio':
    // radio is mapped to <input type='radio' /> i.e. 'radios' element in Drupal Form API
      $input['#type'] = 'radios';

      // Creates options, we must delete array keys to have revealant information
      // on MailChimp
      foreach ($mergevar['choices'] as $choice) {
        $choices[$choice] = $choice;
      }

      $input['#options'] = $choices;
      break;

    default:
    // This is a standard input[type=text] or something we can't handle with Drupal FormAPI
      $input['#type'] = 'textfield';
      $input['#size'] = $mergevar['size'];
      break;
  }

  // Special cases for MailChimp hidden defined fields
  if ($mergevar['public'] == FALSE) {
    $input['#type'] = 'hidden';
  }

  return $input;
}

/**
 * MailChimp unsubscribe form
 *
 * @param <type> $form_values
 * @return <type>
 */
function mailchimp_unsubscribe_form($form_values = array()) {
  $form = array();
  $form['intro'] = array(
    '#type'           => 'markup',
    '#value'          => t(variable_get('mailchimp_unsubscribe_page_description', 'Use this form to unsubscribe from all of our newsletters.')),
  );
  $form['EMAIL'] = array(
    '#type'           => 'textfield',
    '#title'          => t('Email Address'),
    '#required'       => TRUE
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Unsubscribe'),
  );
  return $form;
}

/**
 * submit handler for unsubscribe form
 *
 * @param <type> $form
 * @param <type> $form_state
 */
function mailchimp_unsubscribe_form_submit($form, &$form_state) {
  if ($q = _mailchimp_get_api_object()) {
    $success = FALSE;
    $count = 0;    
    global $user;
    foreach ((array)_mailchimp_get_available_lists($user) as $list) {
      $success = _mailchimp_unsubscribe_user($list, $form_state['values']['EMAIL'], FALSE, $q);
      if ($success) {
        $count ++;
        drupal_set_message(t('Thank you, you have been successfully unsubscribed from !list.', array('!list' => '<em>' . $list->name . '</em>')));
      }
    }
    
    if ($count == 0) {
      drupal_set_message(t('There were no lists to unsubscribe from at this time.'));
    }
  }
}

/**
 * Implementation of hook_mailchimp_merge_keys
 */
function mailchimp_mailchimp_merge_keys() {
  $out = array('' => '<none>');

  $user_fields = array(
      'name'      => t('Username'),
      'mail'      => t('Email Address'),
      'uid'       => t('User ID'),
      'signature' => t("User's Signature"),
      'created'   => t("User's Creation Date"),
      'access'    => t("User's Last Access Date"),
  );

  foreach ($user_fields as $key => $field) {
    $out[$key] = t('User: !field', array('!field' => $field));
  }

  if (function_exists('_profile_get_fields')) {
    $categories = profile_categories();
    if (!empty($categories)) {
      foreach ($categories as $category) {
        $result = _profile_get_fields($category['name']);
        while ($field = db_fetch_object($result)) {
          $out[$field->name] = t('Profile: !cat - !field', array('!cat' => $field->category, '!field' => $field->title));
        }
      }
    }
  }

  if (function_exists('token_get_list')) {
    $tokens = token_get_list(array('user', 'order'));
    if (is_array($tokens['user'])) {
      foreach ($tokens['user'] as $token => $name) {
        $out['token_'. $token] = t('Token: !field', array('!field' => $name));
      }
    }
  }

  return $out;
}

/**
 * Implementation of hook_mailchimp_merge_values
 */
function mailchimp_mailchimp_merge_values($user) {
  $out = array();
  $out = (array)$user;
  foreach ((array)$user as $key => $value) {
    // handle profile dates
    if (is_array($value) && isset($value['month'])) {
      $out[$key] = date('Y-m-d',strtotime(implode('/', $value)));
    }
    // handle time stamps
    else if (in_array($key, array('login', 'access', 'created'))) {
      $out[$key] = date('c', $value);
    }
    else if ($key != 'roles') {
      $out[$key] = $value;
    }
  }
  $out = array_merge($out, _mailchimp_get_user_tokens($user));

  return $out;
}

/**
 * Get the user tokens for merging
 */
function _mailchimp_get_user_tokens($user) {
  $out = array();
  if (function_exists('token_get_values')) {
    $vars = token_get_values('user', $user);
    foreach ($vars->tokens as $key => $value) {
      $out['token_'. $value] = $vars->values[$key];
    }
  }
  return $out;
}

/**
 * Get the available merge var keys
 */
function mailchimp_get_merge_keys() {
  return module_invoke_all('mailchimp_merge_keys');
}

/**
 * Get all the potential merge var values for a given user
 */
function mailchimp_get_merge_values($uid) {
  $values = array();
  if ($user = user_load(array('uid' => $uid))) {
    $values = module_invoke_all('mailchimp_merge_values', $user);
  }
  return $values;
}


/**
 * Get the relevent merge vars for the given user for the given list
 */
function _mailchimp_load_user_list_mergevars($uid, $list_id, $mergevars) {
  $account = mailchimp_get_merge_values($uid);
  $lists = variable_get('mailchimp_lists', array());
  $list = $lists[$list_id];

  $uservars = array(
      'EMAIL' => $account['mail']
  );
  foreach ($mergevars as $mergevar) {
    if (!empty($list->mergevars[$mergevar['tag']]) && $key = $list->mergevars[$mergevar['tag']]) {
      $uservars[$mergevar['tag']] = $account[$key];
    }
  }
  return $uservars;
}

/**
 * Check if the given user is subscribed to the given list
 */
function _mailchimp_is_subscribed($listid, $mail, $q = NULL) {
  $is_subscribed = FALSE;
  if ($q || $q = _mailchimp_get_api_object()) {
    $sub_info       = $q->listMemberInfo($listid, $mail);
    $is_subscribed  = @$sub_info['status'] == 'subscribed';
  }
  return $is_subscribed;
}

/**
 * Subscribe or update a user in a givne list
 */
function _mailchimp_subscribe_user($list, $email, $merge_vars, $message = TRUE, $q = NULL) {
  if ($q || $q = _mailchimp_get_api_object()) {
    $double_optin   = $list->doublein;

    // required by MC API. An empty array will fail.
    if (empty($merge_vars)) {
      $merge_vars = '';
    }

    if (_mailchimp_is_subscribed($list->id, $email, $q)) {
      $action = 'updated in';
      $success = $q->listUpdateMember($list->id, $email, $merge_vars);
      if($success && $message){
        drupal_set_message(t('You have updated %email\'s settings in the %list list.', array('%email' => $email, '%list' => $list->name)));
      }
    }
    else {
      $action = 'subscribed to';
      $success = $q->listSubscribe($list->id, $email, $merge_vars, 'html', $double_optin, TRUE);

      if ($message && $success && $double_optin) {
        drupal_set_message(t('You have chosen to subscribe to %list. An email will be sent to your address. Click the link in the email to confirm the subscription.', array('%list' => $list->name)));
      }
      elseif ($message && $success) {
        drupal_set_message(t('You have subscribed %email to the %list list.', array('%email' => $email, '%list' => $list->name)));
      }
    }
  }

  if ($success) {
    watchdog('mailchimp', '@email was @action list @list.',
      array('@action' => $action, '@email' => $merge_vars['EMAIL'], '@list' => $list->name), WATCHDOG_NOTICE);
  }
  else {
    watchdog('mailchimp', '@email has failed to subscribed to @list.', array('@email' => $merge_vars['EMAIL'], '@list' => $list->name), WATCHDOG_WARNING);
  }

  return $success;
}

/**
 * Unsubscribe the given user from the given list
 */
function _mailchimp_unsubscribe_user($list, $mail, $message = TRUE, $q = NULL) {
  if ($q || $q = _mailchimp_get_api_object()) {
    $success = FALSE;
    if (_mailchimp_is_subscribed($list->id, $mail, $q)) {
      $success = $q->listUnsubscribe($list->id, $mail, FALSE, FALSE, FALSE);
      if ($message && $success) {
        drupal_set_message(t('You have unsubscribed %email from the %list list.', array('%email' => $mail, '%list' => $list->name)));
      }
    }
  }
  
  return $success;
}

/**
 * Get all of the lists that the given user can subscribe to
 */
function _mailchimp_get_available_lists($user) {
  $all_lists = variable_get('mailchimp_lists', array());
  $available_lists = array();
  if (!empty($all_lists)) {
    foreach ($all_lists as $key => $list) {
      foreach ($user->roles as $rid => $info) {
        if (!empty($list->roles[$rid])) {
          $available_lists[$list->id] = $list;
          break;
        }
      }
    }
  }

  return $available_lists;
}

/**
 * Get all of the lists that the given user must be subscribed to
 */
function _mailchimp_get_required_lists() {
  $lists = variable_get('mailchimp_lists', array());
  if (!is_array($lists)) {
    $lists = array();
  }
  else if (!empty($lists)) {
    foreach ($lists as $key => $list) {
      if ($list->listtype !== MAILCHIMP_LISTTYPE_REQUIRED) {
        unset($lists[$key]);
      }
    }
  }
  return $lists;
}

/**
 * Get a Mailchimp API object for communication with the mailchimp server
 */
function _mailchimp_get_api_object() {
  module_load_include('php', 'mailchimp', 'MCAPI.class');

  $q = new MCAPI(variable_get('mailchimp_api_key', ''));
  // set the timeout to something reasonsable to avoid taking down the Drupal site
  $q->setTimeout(60);

  if ($q->errorCode) {
    watchdog('mailchimp', 'MCAPI Error: %errormsg', array('%errormsg' => $q->errorMessage), WATCHDOG_ERROR);
    return NULL;
  }
  return $q;
}

/**
 * implementation of hook_block
 * Provides a block for each available list for a given user
 */
function mailchimp_block($op='list', $delta=0) {
  if ($op == "list") {
    $blocks = array();
    $all_lists = variable_get('mailchimp_lists', array());
    if (!empty($all_lists)) {
      foreach ($all_lists as $key => $list) {
        // exclude required lists
        if ($list->listtype !== MAILCHIMP_LISTTYPE_REQUIRED) {
          $blocks[$list->id] = array(
            'info' => t('Mailchimp Subscription Form: @name', array('@name' => $list->name)),
            'cache' => BLOCK_CACHE_PER_USER,
          );
        }
      }
    }

    return $blocks;
  }
  else if ($op == 'view' && arg(2) != 'mailchimp' && arg(0) != 'mailchimp') {
    $block = array();
    global $user;
    $lists = _mailchimp_get_available_lists($user);
    if (!empty($lists)) {
      if (!empty($lists[$delta]) && $q = _mailchimp_get_api_object()) {
        $list = $lists[$delta];
        $block['subject'] = t('Subscribe to @title', array('@title' => $list->name));;

        if ($user->uid) {
          $block['content'] = drupal_get_form('mailchimp_subscribe_auth_form_' . $list->id, $user, 1, $list);
        }
        else {
          $block['content'] = drupal_get_form('mailchimp_subscribe_anon_form_' . $list->id, $list, $q);
        }
      }
    }

    return $block;
  }
}

/**
 * Rebuild the MailChimp users's table.
 */
function mailchimp_rebuild_users() {
  db_query("DELETE FROM {mailchimp_user}");
  db_query("INSERT INTO {mailchimp_user} (uid, status) SELECT uid, '%s' FROM {users} WHERE uid > 0", MAILCHIMP_USERSTATUS_PENDING);  
  drupal_set_message('The MailChimp User\'s Table has been rebuilt with all user\'s status set to pending.', 'status');
  drupal_goto('admin/settings/mailchimp');
}

/**
 * Escape commas in interest groups and implode if there are multiple
 * values.
 * 
 * @param mixed $groups string with single group or array with groups
 * @return string
 */
function _mailchimp_implode_interest_groups($groups) {
  if (!is_array($groups)) {
    $groups = array($groups);
  }
  else {
    $groups = array_filter($groups);
  }
  foreach ($groups as $key => $group) {
    $groups[$key] = str_replace(',', '\,', $group);
  }
  $groups = implode(',', $groups);
  return $groups;
}

/**
 * Parses interest groups into array and un-escapes commas in group names.
 * 
 * @param string $groups
 * @return array
 */
function _mailchimp_explode_interest_groups($groups) {
  // Split by comma that is not preceded by backslash and followed by
  // zero to one space
  $groups = preg_split('/(?<!\\\\)\,\s?/', $groups);
  foreach ($groups as $key => $group) {
    $groups[$key] = str_replace('\,', ',', $group);
  }
  return $groups;
}