lm_paypal.module

<?php

/**
 * @file
 *
 * PayPal interface.
 */

define('LM_PAYPAL', 'LM_PayPal');

// Don't change these here! Use the admin interface at admin/config/lm_paypal
define('LM_PAYPAL_HOST_DEFAULT', 'www.paypal.com');
define('LM_PAYPAL_OBEY_TEST_IPNS_DEFAULT', 0);
define('LM_PAYPAL_IPNS_MAX_AGE_DEFAULT', 120); // Max hours to keep IPNS

define('LM_PAYPAL_CURRENCY_DEFAULT', 'EUR');

// Never change these unless you really know what you are doing?
define('LM_PAYPAL_DEBUG_DEFAULT', FALSE);
define('LM_PAYPAL_VALIDATE_TIMEOUT', 30);

// Paypal form: handle 'cmd' setting for paypal
define('LM_PAYPAL_FORM_CMD_BUY_NOW',   1);
define('LM_PAYPAL_FORM_CMD_DONATE',    2);
define('LM_PAYPAL_FORM_CMD_SUBSCRIBE', 3);

/**
 * Implements of hook_permission().
 */
function lm_paypal_permission() {
  return array(
    'administer lm_paypal' => array(
      'title' => 'Administer LM PayPal',
      'description' => 'View and modify LM PayPal Settings and payments.'
    )
  );
}

/**
 * Implements of hook_menu().
 */
function lm_paypal_menu() {
  $items = array();

  // Each of the LM Paypal modules has a tab under admin/config/lm_paypal.
  // Their "main settings page" should be the default, and any other
  // view/configure pages should be second-level tabs.
  


  $items['admin/config/lm_paypal'] = array(
    'title' => 'LM PayPal',
    'description' => 'LM PayPal',
    'page callback' => 'system_admin_menu_block_page',
    'access arguments' => array('access administration pages'),
    'file' => 'system.admin.inc',
    'file path' => drupal_get_path('module', 'system'),
  );
  $items['admin/config/lm_paypal/settings'] = array(
    'file' => 'lm_paypal.admin.inc',
    'title' => 'LM PayPal Settings',
    'description' => 'LM PayPal is a set of modules that interface to paypal.com',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('lm_paypal_settings_form'),
    'access arguments' => array('administer lm_paypal'),
  );

  // Tab 1.2: LM Paypal Settings
  $items['admin/config/lm_paypal/ipns'] = array(
    'file' => 'lm_paypal.admin.inc',
    'title' => 'Saved IPNs',
    'description' => 'Show details of all saved PayPal IPN\'s',
    'page callback' => 'lm_paypal_ipns',
    'access arguments' => array('administer lm_paypal'),
    'weight' => 2,
  );

  // Default return path for
  $items['lm_paypal/thanks'] = array(
    'title' => 'Proceeding payment',
    'description' => 'Default return path for paypal payment form'
      . 'This happens only when a custom module does not specify its own.',
    'page callback' => 'lm_paypal_page_thanks',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );

  // Display the details of a saved IPN - internal
  $items['admin/config/lm_paypal/id'] = array(
    'file' => 'lm_paypal.admin.inc',
    'title' => 'Show ID Details',
    'type' => MENU_CALLBACK,
    'page callback' => 'lm_paypal_id',
    'access arguments' => array('administer lm_paypal'),
    'description' => 'Show details of a single saved IPN',
  );

  // URL for PayPal to send IPN (incoming payment notifications) to.
  $items['lm_paypal/ipn'] = array(
    'file' => 'lm_paypal.ipn.inc',
    'title' => 'LM PayPal Incoming IPN',
    'type' => MENU_CALLBACK,
    'page callback' => 'lm_paypal_ipn_in',
    'access callback' => TRUE,
  );

  return $items;
}

/**
 * Implements of hook_theme().
 */
function lm_paypal_theme() {
  return array(
    'lm_paypal_payment_form' => array(
      'arguments' => array('form' => array()),
      'file' => 'lm_paypal.theme',
    ),
    'lm_paypal_amount' => array(
      'arguments' => array($options = array()),
      'file' => 'lm_paypal.theme',
    ),
  );
}

/**
 * Implements of hook_cron().
 */
function lm_paypal_cron() {
  _lm_paypal_clean_stored_ipns();
}

/**
 * Implements of hook_requirements().
 */
function lm_paypal_requirements($phase) {
  $requirements = array();
  $t = get_t();

  if ($phase == 'runtime') {
    if (! lm_paypal_api_get_business()) {
      $requirements['lm_paypal'] = array(
        'title' => t('LM PayPal'),
        'severity' => REQUIREMENT_ERROR,
        'value' => $t('LM PayPal default business address is not configured. Please set it in <a href="!admin_page">administration page</a>', array(
          '!admin_page' => url('admin/config/lm_paypal/settings'),
        )),
      );
    }
  }

  return $requirements;
}

/**
 * Tells if module is in debug mode.
 * 
 * @return boolean
 *   TRUE if lm_paypal is in debug mode
 */
function lm_paypal_debug() {
  return (bool) variable_get('lm_paypal_debug', LM_PAYPAL_DEBUG_DEFAULT);
}

/**
 * Get the configured paypal host.
 * 
 * @param boolean $url = FALSE
 *   If set to TRUE, return the webscr full absolute URL
 * @return string
 *   Paypal hostname
 */
function lm_paypal_api_get_host($full_url = FALSE) {
  $hostname = variable_get('lm_paypal_host', LM_PAYPAL_HOST_DEFAULT);
  if ($full_url) {
    return 'https://' . $hostname . '/cgi-bin/webscr';
  }
  return $hostname;
}

/**
 * Return the notify url. Every module that uses this one's API but a custom
 * payement form should use this method.
 * 
 * @return string
 *   Notify url for paypal
 */
function lm_paypal_api_get_notify_url() {
  return url('lm_paypal/ipn', array('absolute' => TRUE));
}

/**
 * Get the configured paypal business.
 * 
 * @return string
 *   Paypal business name
 */
function lm_paypal_api_get_business() {
  return variable_get('lm_paypal_business', '');
}

/**
 * TODO: use currency module if they have it? http://drupal.org/project/currency
 * Get currency localized textual description or symbol.
 * 
 * If you don't specify a currency code you want, this function will return an
 * array containing all the lm_paypal supported currencies descriptions.
 * 
 * @param string $currency = NULL
 *   (optional) If set, the function will return only the given currency code
 *   data.
 * @param boolean $syms = FALSE
 *   (optional) If set to TRUE, return the given currency symbol instead of the
 *   currency localized textual description.
 * @return mixed
 *   Data (string) about one currency or array of all support currencies
 *   NULL if $currency is unknown.
 */
function lm_paypal_api_get_currency($currency = NULL, $syms = FALSE) {
  static $currencies_text, $currencies_syms;
  // TODO:plurals
  if (! $syms && ! $currencies_text) {
    $currencies_text = array(
      // '' => t('default currency'),  Force a currency to be specified
      'USD' => t('U.S. Dollar'),
      'GBP' => t('Pound Sterling'),
      'EUR' => t('Euro'),
      'AUD' => t('Australian Dollar'),
      'CAD' => t('Canadian Dollar'),
      'JPY' => t('Japanese Yen'),
      'CHF' => t('Swiss Franc'),
      'CZK' => t('Czech Koruna'),
      'DKK' => t('Danish Krone'),
      'HKD' => t('Hong Kong Dollar'),
      'HUF' => t('Hungarian Forint'),
      'NOK' => t('Norwegian Krone'),
      'NZD' => t('New Zealand Dollar'),
      'PLN' => t('Polish Zloty'),
      'SEK' => t('Swedish Krona'),
      'SGD' => t('Singapore Dollar'),
    );
  }
  if ($syms && ! $currencies_syms) {
    $currencies_syms = array(
      '' => '?',
      'AUD' => 'AUD$',
      'CAD' => 'Can$',
      //'EUR' => '&euro;',  This causes problems depending on the fonts
      // available and the version of the browser used
      // TODO: pounard: I think we should write the real Euro sign (€)
      'EUR' => 'Euro',
      'GBP' => '&#163;',
      'JPY' => '&#165;',
      'USD' => '$',
      'CHF' => 'CHF',   // Yes - it really is writen as CHF
      'CZK' => 'Kc',
      'DKK' => 'kr',
      'HKD' => 'HK$',
      'HUF' => 'Ft',
      'NOK' => 'kr',
      'NZD' => 'NZ$',
      'PLN' => 'zl',  // I cannot find the HTML character for a crossed l
      'SEK' => 'kr',
      'SGD' => 'S$',
    );
  }

  if ($currency) {
    return $syms ? $currencies_syms[$currency] : $currencies_text[$currency];
  }
  elseif (! $currency) {
    return $syms ? $currencies_syms : $currencies_text;
  }
}

/**
 * Get default configured currency code.
 * 
 * @return string
 *   3 letter paypal currency identifier
 */
function lm_paypal_api_get_currency_default() {
  return variable_get('lm_paypal_currency_default', LM_PAYPAL_CURRENCY_DEFAULT);
}

// TODO: pounard: This method should be owned by subscription module, right?
function lm_paypal_api_get_period_unit_list($default = FALSE) {
  static $cache;
  if (! $cache) {
    $cache = array(
      'D' => t('Days'),
      'W' => t('Weeks'),
      'M' => t('Months'),
      'Y' => t('Years'),
    );
  }
  if ($default) {
    return array(NULL, t('Default')) + $default;
  }
  else {
    return $cache;
  }
}

function _lm_paypal_clean_stored_ipns() {
  $ipns_max_age = (int) variable_get('lm_paypal_ipns_max_age', LM_PAYPAL_IPNS_MAX_AGE_DEFAULT);
  // Do not launch this action if no max age is specified (keep for ever).
  if ($ipns_max_age > 0) {
    if (lm_paypal_debug()) {
      watchdog(LM_PAYPAL, 'cron');
    }
    $max_age = time() - ($ipns_max_age * 3600);
    $num_deleted = db_delete('lm_paypal_ipns')
                      ->condition('timestamp', $max_age , '<')
                      ->execute();
  }
}

/**
 * Default return_path for paypal.
 * 
 * @return string
 *   (x)html output
 */
function lm_paypal_page_thanks() {
  return t('Thanks for your payment.');
}

/**
 * Default payment form. Highly customisable.
 * 
 * This form display the item_name, the price/currency and a paypal submit
 * button.
 * It should fit for most cases. Either your form does not fit here or not,
 * then think about get this form and alter it. Since it does not have any
 * validate or submit function (action is the real paypal host), you don't
 * have to care if you override it.
 * 
 * Note that, at least one parameter is mandatory: the amount. You may get
 * back the form and change it to a input box, but without validation this
 * is dangerous, your users should go through a business validation process
 * before getting to this form.
 *
 * @param $form_state
 *   Form API stuff.
 *
 * @param mixed $amount
 *   You can pass either a float value that will be passed in an hidden field
 *   either an array of integers values, which will display a select.
 *   TODO: re-add support for a textfield with pre-populated value
 *
 * @param array $options = array()
 *   (optional) Pairs of setting => custom value where setting can be:
 *
 *     'item_name': integer
 *        Textual human-readable representation of item.
 *        Default is localized string 'Donation' (ok, 'Unknown' is not a very
 *        sexy item name to display to user).
 *
 *     'item_number': integer
 *        Item number (depends on your business code)
 *        Default is 0.
 *
 *     'currency_code': string
 *        Paypal 3 letters currency code, see lm_paypal_api_get_currency().
 *        Default is default configured currency in lm_paypal main module.
 *
 *     'custom': array
 *        Keyed array of data you might want to pass through PayPal processing
 *        and get back later when processing the incoming IPN
 *
 *     'return_path': string
 *        May be this one is the only one interesting for you, you should pass
 *        a drupal path where you want to redirect your user after he procedeed
 *        his payment.
 *        Default is a page displaying the thanks message from lm_paypal main
 *        module.
 *        Note that if the path is not valid, then lm_paypal default will be
 *        used.
 * 
 *     'cancel_path': string
 *        Internal path in case of cancel. If not specified, it will use
 *        return_path setting.
 *
 *     'text': string
 *        (x)html text to display over the form (eg: 'Validate your command').
 *        Don't forget to check_plain() your text!
 *        Default is no text displayed.
 *
 *     'button': array
 *        'text': string
 *            Whatever you want to display on submit button.
 *
 *        'url': string
 *          In case you want to display a image from an external (or internal)
 *          website, use this opton to put the url.
 *          Note that if you specify this, button_text will be used as alternative
 *          text for the image.
 *
 *     'amount_label': string
 *        Changes the label for the select textfield/selectfield
 *
 *     'display_amount': boolean
 *        Set this to FALSE if you dont want the price to be displayed (or if
 *        you want to display it yourself in the 'text' setting).
 *        Default is amount is displayed.
 *        Note that if you gave an array of amounts, it will remain FALSE,
 *        whatever you pass to this option.
 *
 *     'hidden': array
 *        Keyed array of values you want to pass as hidden values through paypal
 *        form.
 *        Advanced usage only!
 *
 *   @param string $type: int
 *      One of the LM_PAYPAL_FORM_CMD_* constants, this changes the 'cmd' form
 *      setting sent to paypal.
 *      Default is LM_PAYPAL_FORM_CMD_BUY_NOW
 *
 *     More to come, module in active development.
 *
 * @return array
 *   Drupal well formated form you can then build with drupal's form API.
 *   Or FALSE if amount is not a valid positive float.
 */
function lm_paypal_api_payment_form($form, $form_state, $amount, $options = array(), $type = LM_PAYPAL_FORM_CMD_DONATE) {

  // Check for the different forms of $amount allowed: either a value, or an
  // array of values (with the default value being [value] rather than value.

  $valid_amount   = NULL;
  $default_amount = FALSE;

  // Check amount is valid
  if (is_array($amount) && ! empty($amount)) {
    $valid_amount = array();

    foreach ($amount as $key => $value) {
      if (is_array($value)) {
        $default_amount = $value = current($value);
      }

      // Always prefer casts to *_val() php functions.
      if (( (float) $value) > 0) {
        $valid_amount["$value"] = $value;
      }
    }

    $amount_is_valid = ! empty($amount);
  }
  else {
    $valid_amount = (float) $amount;
  }

  if (empty($valid_amount)) {
    return array();
  }
  elseif (is_array($valid_amount)) {
    $options['display_amount'] = FALSE;
  }

  global $user;
  // Check our user can access to return path
  if (isset($options['return_path']) && drupal_valid_path($options['return_path'])) {
    $return_url = url($options['return_path'], array('absolute' => TRUE));
  }
  else {
    $return_url = url($_GET['q'], array('query' => NULL, 'fragment' => NULL, 'absolute' => TRUE));
  }
  // And cancel path if set
  if (isset($options['cancel_path']) && drupal_valid_path($options['cancel_path'])) {
    $cancel_url = url($options['cancel_path'], array('absolute' => TRUE));
  }
  else {
    $cancel_url = $return_url;
  }

  // Check for a specified currency
  $currency_code = isset($options['currency_code']) ? $options['currency_code'] : lm_paypal_api_get_currency_default();

  $button_text = t('Proceed to paypal.com');
  
  // And check for button customization
  if (isset($options['button']) && is_array($options['button'])) {
    if (isset($options['button']['url']) && check_url($options['url'])) {
      $button_url = $options['url'];
    }
    if (isset($options['button']['text'])) {
      $button_text = check_plain($options['button']['text']);
    }
  }

  $form['#action'] = lm_paypal_api_get_host(TRUE);
  $form['business'] = array(
    '#type' => 'hidden',
    '#name' => 'business',
    '#value' => lm_paypal_api_get_business(),
  );

  // Check for paypal cmd type
  switch ($type) {
    case LM_PAYPAL_FORM_CMD_SUBSCRIBE:
      $cmd = '_xclick-subscriptions';
      break;

    case LM_PAYPAL_FORM_CMD_DONATE:
      $cmd = '_donations';
      break;

    case LM_PAYPAL_FORM_CMD_BUY_NOW:
    default:
      $cmd = '_xclick';
      break;
  }

  $form['cmd'] = array(
    '#type' => 'hidden',
    '#value' => $cmd,
    '#name' => 'cmd',
  );

  $form['item_name'] = array(
    '#type' => 'hidden',
    // We will let empty name pass, sub module developers should be aware.
    '#value' => isset($options['item_name']) ? check_plain($options['item_name']) : t('Donation'),
    '#name' => 'item_name',
  );
  $form['item_number'] = array(
    '#type' => 'hidden',
    '#value' => isset($options['item_number']) ? ((int) $options['item_number']) : 0,
    '#name' => 'item_number',
  );
  $form['no_shipping'] = array(
    '#type' => 'hidden',
    '#value' => 1,
    '#name' => 'no_shipping',
  );
  $form['return'] = array(
    '#type' => 'hidden',
    '#value' => $return_url,
    '#name' => 'return',
  );
  $form['cancel_return'] = array(
    '#type' => 'hidden',
    '#value' => $cancel_url,
    '#name' => 'cancel_return',
  );
  $form['currency_code'] = array(
    '#type' => 'hidden',
    '#value' => $currency_code,
    '#name' => 'currency_code',
  );
  if (isset($options['text'])) {
    $form['amount_text'] = array(
      '#type' => 'markup',
      '#markup' => $options['text'],
    );
  }
  
  // Either display the textfield or the select
  if (is_array($valid_amount)) {
    $textual_currency = lm_paypal_api_get_currency($currency_code, FALSE);
    if (! $textual_currency) {
      $textual_currency = $currency_code;
    }
    $label = t('Select an amount');
    $form['amount'] = array(
      '#type' => 'select',
      '#options' => $valid_amount,
      '#description' => t('Value is @currency', array('@currency' => $textual_currency)),
    );
    
    if ($default_amount) {
      $form['amount']['#default_value'] = $default_amount;
    }

    if (count($valid_amount) === 1) {
      $label = t('Enter an amount');
      $form['amount']['#type'] = 'textfield';
      $form['amount']['#value'] = current($valid_amount);
      $form['amount']['#size'] = '';
      unset($form['amount']['#options']);
    }
    
    //use label if set
    if (isset($options['amount_label'])) {
      $label = $options['amount_label'];
    }
    
    $form['amount']['#title'] = t($label); 
  }
  else {
    if (isset($options['display_amount']) && $options['display_amount']) {
      $form['amount_display'] = array(
        '#type' => 'markup',
        '#markup' => '<p>' . t('Proceed with your !price payment', array(
          '!price' => theme('lm_paypal_amount', array('amount' => $valid_amount, 'cc' => $currency_code)))) . '</p>',
      );
    }
    $form['amount'] = array(
      '#type' => 'hidden',
      '#value' => $valid_amount,
      '#name' => 'amount',
    );
  }
  $form['notify_url'] = array(
    '#type' => 'hidden',
    '#value' => lm_paypal_api_get_notify_url(),
    '#name' => 'notify_url',
  );
  if (empty($options['custom']) || !is_array($options['custom'])) {
    $options['custom'] = array();
  }
  $options['custom']['uid'] = $user->uid;
  $form['custom'] = array(
    '#type' => 'hidden',
    '#value' => serialize($options['custom']),
    '#name' => 'custom',
  );
  
  if (isset($options['hidden_fields']) && is_array($options['hidden_fields']) && ! empty($options['hidden_fields'])) {
    foreach ($options['hidden_fields'] as $key => $value) {
      // Do not override existing values
      if (! isset($form[$key])) {
        $form[$key] = array(
          '#type' => 'hidden',
          '#value' => check_plain($value),
        );
      }
    }
  }

  if (isset($button_url) && $button_url) {
    $form['submit'] = array(
      '#type' => 'image_button',
      '#value' => $button_text,
      '#attributes' => array('src' => $button_url),
      '#name' => 'submit',
    );
  }
  else {
    $form['submit'] = array(
      '#type' => 'submit',
      '#value' => $button_text,
      '#name' => 'submit',
    );
  }
  return $form;
}

// =====================================================================
// Below this line, module has not been "cleaned up"
// TODO: pounard except the mail functions, it's almost fully "cleaned up".





/**
 * Implements of hook_help().
 *
 * TODO: must be fully rewritten
 */
/*
 function lm_paypal_help($path, $arg) {

  $admin = l('LM PayPal Admin', 'admin/config/lm_paypal');
  $access = l('administer permissions', 'admin/people/permissions');

  $help = l('LM PayPal Help', 'admin/help/lm_paypal');
  $ipn = url('lm_paypal/ipn', array('query' => NULL, 'fragment' => NULL, 'absolute' => TRUE));

  switch ($path) {
    case 'admin/help#lm_paypal':
      $output = $_lm_paypal_welcome;

      $output .= '<p>'. t('If you are not already familar with PayPal please go to their <a href="http://www.paypal.com">website</a> and read up.') .'</p>';
      $output .= '<p>'. t('If you are new to this module you need to:');
      $output .= '<ul>';
      $output .= '<li>'. t("Update the site specific settings via !admin. Normally you only need to provide your PayPal Business/Premier Email.", array("!admin" => $admin)) .'</li>';
      $output .= '<li>'. t("On PayPal login to your Business/Premier account. Under <b>Profile</b> go to <b>Instant Payment Notification Preferences</b> and enable IPN.") .'</li>';
      $output .= '<li>'. t("To have lm_paypal handle IPN messages that it did not generate, such as a Send Money originated from PayPal.com, also set the IPN URL to: <pre>!ipn</pre><br/>However it could be set to another url perhaps for ecommerce", array("!ipn" => $ipn)) .'</li>';
      $output .= '<li>'. t('While on PayPal if you plan to handle multiple currencies then go to <b>Payment Receiving Preferences</b>. For the entry <b>Block payments sent to me in a currency I do not hold:</b> I suggest setting it either <b>Yes</b> (to block them) or <b>No, accept them and convert them to ...</b>. If set on <b>Ask Me</b> then each payment will have to be manually confirmed!') .'</li>';
      $output .= '<li>'. t('Next configure one of the LM PayPal services such as subscriptions, donations or paid adverts') .'</li>';
      $output .= '</ul>';
      return $output;

      // This is the brief description of the module displayed on the modules page
    case 'admin/modules#description':
      // New to Drupal 5 (because the page has moved)
    case 'admin/config/modules#description':
      return t("Lowest level PayPal interface required by other LM PayPal modules. Once enabled go to !admin and configure the site specific settings.", array("!admin" => $admin));

      // Help at the start of admin/config/lm_paypal
    case 'admin/config/lm_paypal':
      $output = $_lm_paypal_welcome;

      $output .= '<p>'. t("If you are looking to configure LM PayPal please follow the instructions !help.", array("!help" => $help)) .'</p>';
      return $output;

      //case 'admin/help#settings/lm_paypal': // causes a [more help] to appear
      //case 'admin/help/settings/lm_paypal': // clicking [more help] gets this
      // This appears at the start of the module settings page before the options
    case 'admin/config/lm_paypal':
      $output = $_lm_paypal_welcome;

      $output .= '<p>'. t("If you have not done so already you will need to configure the LM PayPal modules and your PayPal business account.  Please follow the instructions !help.", array("!help" => $help)) .'</p>';
      return $output;

      // This appears at the start of the IPNs viewing page before the options
    case 'admin/config/lm_paypal/ipns':
      $output = $_lm_paypal_welcome;

      $output .= '<p>'. t('These are the IPN messages received from PayPal.') .'</p>';
      return $output;
  }
}
*/





/**
 * Validates a formelement to ensure it is shaped like an email
 *
 * @param $formelement
 *   The form element to be checked.
 *
 * If the element fails any of the tests form_set_error() is called.
 */
function lm_paypal_is_email_shaped($formelement) {
  $biz = $formelement['#value'];
  $fieldname = $formelement['#name'];
  if (strpos($biz, '@') === FALSE) {
    form_set_error($fieldname, t('Email address required.'));
  }
}

/**
 * Validates a formelement to ensure it is a number inside a given range.
 *
 * @param $formelement
 *   The form element to be checked.
 * @param $min
 *   If present the minimum value the element is allowed to have
 * @param $max
 *   If present the maximum value the element is allowed to have
 *
 * If the element fails any of the tests form_set_error() is called.
 * Based on code by Coyote see http://drupal.org/node/36899
 */
function lm_paypal_is_integer_between($formelement, $min = NULL, $max = NULL) {
  $thevalue = $formelement['#value'];
  $fieldname = $formelement['#name'];
  if (is_numeric($thevalue)) {
    $thevalue = $thevalue + 0;
  }
  else {
    form_set_error($fieldname, t('Item entered must be an integer.'));
  }
  if (!is_int($thevalue)) {
    form_set_error($fieldname, t('Item entered must be an integer.'));
  }
  else {
    if (isset($min) && ($thevalue < $min)) {
      form_set_error($fieldname, t('Item entered must be no smaller than:%min', array('%min' => $min)));
    }
    elseif (isset($max) && ($thevalue > $max)) {
      form_set_error($fieldname, t('Item entered must be no greater than:%max', array('%max' => $max)));
    }
  }
}

/**
 * Register the handler function for a range of item_numbers
 *
 * @param $function_name
 *   The function to call when an item number in the given range arrives
 * @param $min
 *   The minimum item_number in the range
 * @param $max
 *   The maximum item_number in the range
 * @return
 *   If $function_name is set then nothing is returned. If null then
 *   the entire registered array of ($fun, $min, $max) is returned.
 */
/*
 function lm_paypal_web_accept_register($function_name = NULL, $min = NULL, $max = NULL) {
  static $ranges = NULL;

  if (is_null($function_name)) {
    return $ranges;
  }

  if (is_null($ranges)) {
    $ranges = array();
  }
  $ranges[] = array('fun' => $function_name, 'min' => $min, 'max' => $max);
}
*/


/**
 * Mark a saved IPN as processed.
 *
 * @param $ipn
 *  The IPN to be marked.
 */
function lm_paypal_mark_processed($ipn) {
  $update = db_update('lm_paypal_ipns')
    ->fields(array('processed' => 1))
    ->condition('id', $ipn->id)
    ->execute();
}

function lm_paypal_already_processed($txn_id) {
  // Has this transaction already been processed?
  // Changed to allow for echecks which can be payment_status = 'Pending' for
  //  quite a while
  $query = db_select('lm_paypal_ipns', 'ipns')
    ->condition('txn_id', $txn_id)
    ->condition('processed', 1)
    ->condition('payment_status', 'Completed');
  return $query->countQuery()->execute()->fetchField();
}

/**
 * Finds the option value corresponding to a period unit
 *
 * @param $count
 *   The number of units
 * @param $unit
 *   A period unit such 'D' or 'W'
 * @return
 *   The string representation of the unit such as '1 day' or '3 weeks'
 */
function lm_paypal_unit2str($count, $unit) {
  switch ($unit) {
    case 'D':
      return format_plural($count, '1 day', '@count days');
    case 'W':
      return format_plural($count, '1 week', '@count weeks');
    case 'M':
      return format_plural($count, '1 month', '@count months');
    case 'Y':
      return format_plural($count, '1 year', '@count years');
    default:
      drupal_set_message(t("Unknown unit-type: $unit", 'error'));
      return $count . ' ' . $unit;
  }
}


/**
 * Returns the number of days given a period and unit
 *
 * @param $period
 *   An integer period
 * @param $unit
 *   A time unit such as 'D', 'W' ...
 * @return
 *   The equivalent number of days
 */
function lm_paypal_period_unit2days($period, $unit) {
  $multiply = 1;
  switch ($unit) {
    case 'D':
      $multiply = 1;
      break;
    case 'W':
      $multiply = 7;
      break;
    case 'M':
      $multiply = 31;
      break;
    case 'Y':
      $multiply = 365;
      break;
  }

  return $period * $multiply;
}

/**
 * Email a user
 *
 * TODO ok young padawan: for tokens, we should use token module, no?
 * But I don't know, I'm not sure this will usefull.
 *
 * @param $to_uid
 *   The uid of user to send this email to
 * @param $about_uid
 *   The uid of the user this email is about
 * @param $subject
 *   The subject line of the email (note it will be run thru strtr() and t())
 * @param $message
 *   The body of the email (note it will be run thru strtr() and t())
 * @param $var
 *   An array of name,value pairs that will be added to the builtin arrary
 *   before being expanded using strtr()
 *
 * Will email the $to_uid user an email. The subject and message will first
 * be expanded with all the variables being replaced by values.
 *  In addition to any vars passed in the following are also present
 * %Username = about_uid's username
 * %Login = about_uid's login
 * %Site' = the local site name
 * %Uri' = the local url
 * %Uri_brief' = the local url without leading http://
 * %Mailto = to_uid's email address
 * %Date' = the date-time
 * (In case you are wondering why they all begin with a capital letter this
 *  is to avoid them clashing with db_query's % handling.  There is probably
 *  a better way around this but there was nothing mentioned in the
 *  documentation.)
 */
function lm_paypal_mail_user($to_uid, $about_uid, $subject, $message, $vars) {
  // TODO: use Token module
  global $base_url;

  if (lm_paypal_debug()) {
    watchdog(LM_PAYPAL, "lm_paypal_mail_user($to_uid, $about_uid, $subject, $message, $vars)", NULL);
  }

  $to_account = user_load($to_uid);
  $to = $to_account->mail;

  $about_user = user_load($about_uid);

  //TODO: Maybe use the subscription adminstrators email instead?
  $from = variable_get('site_mail', ini_get('sendmail_from'));

  $variables = array(
    '%Username' => $about_user->name,
    '%Login' => $about_user->login,
    '%Site' => variable_get('site_name', 'drupal'),
    '%Uri' => $base_url,
    '%Uri_brief' => substr($base_url, strlen('http://')),
    '%Mailto' => $to,
    '%Date' => format_date(time()),
  );
  $variables = $variables + $vars;

  $body = strtr(t($message), $variables);
  $subject = strtr(t($subject), $variables);

  watchdog(LM_PAYPAL, 'Sending mail to: ' . $to, NULL);

  //drupal_mail('lm_paypal', $to, $subject, $body, $from);

  $params['subject'] = $subject;
  $params['body'] = $body;

  $func = 'drupal_mail';
  $args = array('lm_paypal', 'notify', $to, user_preferred_language($to_account), $params);

  call_user_func_array($func, $args);
}

function lm_paypal_mail($key, &$message, $params) {
  // TODO: stuff needs moving here from above function!
  switch ($key) {
    case 'notify':
      // $language = $message['language'];
      $message['subject'] = $params['subject'];
      $message["body"] = array($params["body"]);
      break;
  }
}

/**
 * Extract data from the 'custom' field in an IPN.  The old way LM Paypal did it
 * was by bit-packing into a 32-bit integer. The new way is PHP serialized data.
 *
 * @return array
 *   An associative array with at least 'uid' and 'other'
 */
function lm_paypal_unpack_ipn_custom($ipn) {
  if ($ipn && isset($ipn->custom)) {       
    if (is_int($ipn->custom)) {
      // Old bit-packing format for 'custom'. The uid is in the bottom of 'custom'
      return array('uid' => $ipn->custom & 0xFFFF, 'other' => ($ipn->custom >> 16) & 0xFFFF);
    }
    else {
      // New serialized data
      return @unserialize($ipn->custom); // In case the passed string is not unserializeable, FALSE is returned and E_NOTICE is issued.
    }
  }
  else {
    // Not set
    return array();
  }
}