<?php
// $Id: spread.module,v 1.3 2008/07/03 07:38:29 jchatard Exp $

/**
 * Implementation of hook_menu().
 */
function spread_menu($may_cache) {
  $items = array();
  if ($may_cache) {
    $items[] = array(
      'path'     => 'spread/js',
      'callback' => 'spread_js',
      'type'     => MENU_CALLBACK,
      'access'   => user_access('use spread form'),
    );
    $items[] = array(
      'path'        => 'admin/settings/spread',
      'title'       => t('Spread') ,
      'description' => t('Manage Spread e-mail messages'),
      'callback'    => 'drupal_get_form',
      'callback arguments' => array('spread_admin_settings'),
      'access'      => user_access('administer site configuration'),
    );
  }
  return $items;
}

/**
 * Implementation of hook_perm().
 */
function spread_perm() {
  return array('use spread form');
}

function spread_admin_settings() {
  $form = array();
  
  $form['spread']['subject'] = array(
    '#title' => t('Subject'),
    '#type'  => 'textfield',
    '#required' => TRUE,
    '#default_value' => variable_get('spread_subject', t('You need to discover this!')),
    '#description' => t('The subject of the e-mail which will be sent.'),
  );
  
  $form['spread']['body'] = array(
    '#title' => t('Body'),
    '#type'  => 'textarea',
    '#required' => TRUE,
    '#default_value' => variable_get('spread_body', t("Hi,\n!sender_email thinks that you should review this web page:\n!url")),
    '#description' => t("This is the message which will be sent. You can use the following placeholders to adjust it:<br /><em>!sender_email</em>: user e-mail who spread the word<br /><em>!url</em>: web page from which the user spread the word"),
  );
  
  $form['spread']['how_many']= array(
    '#title' => t("How many e-mail fields?"),
    '#type'  => 'textfield',
    '#required' => TRUE,
    '#default_value' => variable_get('spread_how_many', 3),
    '#description' => t('This is the number of e-mail fields which will be generated on the spread block form.'),
    '#size' => 2,
    '#maxlength' => '2',
  );
  
  return system_settings_form($form);
}

function spread_admin_settings_validate($form_id, $form_values) {
  // Is entered value for field count is number?
  if (!is_numeric($form_values['how_many'])) {
    form_set_error('how_many', t('You must enter a numeric value'));
  }
  if ((int)$form_values['how_many'] == 0) {
    form_set_error('how_many', t('0 seems to be not enough!'));
  }
}

function spread_admin_settings_submit($form_id, $form_values) {
  variable_set('spread_subject',  $form_values['subject']);
  variable_set('spread_body',     $form_values['body']);
  variable_set('spread_how_many', $form_values['how_many']);
  
  drupal_set_message(t('Configuration saved.'));
}

function spread_block($op = 'list', $delta = 0, $edit = array()) {
  switch ($op) {
    case 'list':
      $blocks[0]['info'] = t('Spread form');
      return $blocks;
    case 'view':
      switch ($delta) {
        case 0:
          // Checking user_access
          if (user_access('use spread form')) {
            $block['subject'] = t('Spread the word');
            $block['content'] = drupal_get_form('spread_form');
            drupal_add_js('Drupal.basePath = "'. base_path() .'"', 'inline');
            drupal_add_js("Drupal.q = '". $_GET['q'] ."'", 'inline');
            drupal_add_js(drupal_get_path('module', 'spread') .'/spread.js');
            drupal_add_css(drupal_get_path('module', 'spread') .'/spread.css');
          }
          break;
      }
      return $block;
  }
}

function spread_form() {
  // We need this to get user's email
  global $user;
  
  $form['thank_you'] = array(
    '#prefix' => "<div id=\"spread-thank-you\">",
    '#value'  => t('Thank you for spreading the word!'),
    '#suffix' => "</div>",
  );
  
  $form['friends_label'] = array(
    '#prefix' => '<label><strong>',
    '#value'  => t("Your friend's e-mail:"),
    '#suffix' => '</strong></label>'
  );
  
  for ($i = 0; $i < variable_get('spread_how_many', 3); $i++) {
    $form['to'][] = array(
      '#type' => 'textfield',
      '#size' => 20,
      '#name' => 'to[]',
      '#default_value' => $_POST['to'][$i],
    );
  }
  
  $form['from'] = array(
    '#type'  => 'textfield',
    '#title' => t('Your e-mail'),
    '#size'  => 20,
    '#default_value' => $user->mail,
  );
  
  $form['submit'] = array(
    '#type'  => 'submit',
    '#value' => t('Spread the word'),
  );
  
  return $form ;
}

function spread_form_validate($form_id, $form_values) {
  
  $error = FALSE;
  
  foreach ($_POST['to'] as $key => $mail) {
    $form_values['to'][] = $mail;
    
    if (!valid_email_address($mail) && trim($mail) != '') {
      $error = TRUE;
      unset($_POST['to'][$key]);
    }
    
    if (trim($mail) == '') {
      unset($_POST['to'][$key]);
    }
  }
  
  if (!valid_email_address($form_values['from'])) {
    $error = TRUE;
  }
  
  if ($error == TRUE) {
    form_set_error('', t('E-mail adresses must be valid'));
  }
  
}

function spread_form_submit($form_id, &$form_values) {
  spread_send_email($_POST['to'], $form_values['from']);
}

function spread_send_email($to = array(), $from = NULL, $js = FALSE) {
  $subject = variable_get("spread_subject", NULL);
  
  $body = variable_get("spread_body", NULL);
  
  $headers = array('Content-Type' => 'text/html; charset=UTF-8; format=flowed');
  
  if (!$js) {
    $url = url($_GET['q'], $query = NULL, $fragment = NULL, $absolute = TRUE);
  }
  else {
    $url = url($_POST['url'], $query = NULL, $fragment = NULL, $absolute = TRUE);
  }
  
  foreach ($to as $mail) {
    
    $placeholders = array(
      "!sender_email" => $from,
      "!url"          => $url,
      '!mail'         => $mail,
    );
    
    drupal_mail("spread", $mail, check_plain(t($subject, $placeholders), FILTER_FORMAT_DEFAULT, FALSE), check_markup(t($body, $placeholders), FILTER_FORMAT_DEFAULT, FALSE), $from, $headers);
    
    $watchdog_message = t("!sender_email has spread the word to !mail on !url", $placeholders);
    
    watchdog('spread', $watchdog_message, $severity = WATCHDOG_NOTICE);
  }
  
  if (!$js) {
    drupal_set_message(t('Thank you for spreading the word!'));
  }
}

function spread_js() {
  global $user;
  
  if (!user_access('use spread form')) {
    die();
  }
  
  if (($emails = spread_js_validate($_POST['to'], $_POST['from'])) != FALSE) {
    spread_send_email($emails['to'], $emails['from'], $js = TRUE);
    print "TRUE";
  }
  else {
    print "FALSE";
  }
  die();
}

function spread_js_validate($adresses = array(), $from = NULL) {
  
  $error = FALSE;
  foreach ($adresses as $key => $mail) {
    $to[] = $mail;
    if (!valid_email_address($mail) && trim($mail) != '') {
      $error = TRUE;
      unset($adresses[$key]);
    }
    if (trim($mail) == '') {
      unset($adresses[$key]);
    }
  }
  if (!valid_email_address($from)) {
    $error = TRUE;
  }
  
  if (count($adresses) < 1) {
    $error = TRUE;
  }
  
  if ($error == TRUE) {
    print "FALSE";
    // Stop here, email aren't valid
    die();
  }
  return array(
    'to'   => $adresses,
    'from' => $from,
  );
}