<?php

/**
 * @file
 * Functions for stripe payment integration
 * @see https://github.com/ericthelast/drupal-stripe-form and https://www.webomelette.com/drupal-stripe-integration
 */

 /**
 * Get the current stripe api public key
 */
function _booking_get_stripe_public_key() {
  if (variable_get('booking_stripe_testmode', 0) == 1) {
    return variable_get('booking_stripe_test_public_key', '');
  }
  else {
    return variable_get('booking_stripe_live_public_key', '');
  }
}

/**
 * Get the current stripe api private key
 */
function _booking_get_stripe_private_key() {
  if (variable_get('booking_stripe_testmode', 0) == 1) {
    return variable_get('booking_stripe_test_secret_key', '');
  }
  else {
    return variable_get('booking_stripe_live_secret_key', '');
  }  
}

/**
 * Helper function to calculate stripe transaction fees
 */
function _booking_add_stripe_fees($amount, $country) {
	//add the 30 cent fixed cost
	$result = '0.00';
	$result = (float) ($amount + (float) variable_get('booking_stripe_transaction_fee_fixedcost', '0.3'));
	
	//and the 2.6 percent transaction fee for australian transaction with no currency conversion
	if ($country == variable_get('booking_default_country', 'Australia')) {
		$percentage = (float) variable_get('booking_stripe_transaction_fee_percentage', '1.75');
	} else {
		$percentage = (float) variable_get('booking_stripe_transaction_fee_percentage_intl', '2.9');
	}
	
	//apply the percentage
	$percentage = (float) $percentage / 100;
	$result = $result / (1 - $percentage);
	
	//return result
	return $result;
}

/**
 * Helper function to generate paypal form for payments
 */
function _booking_stripe_form($person, $invoiceid, $net_amount_owing, $button_text) {
  $payment_form = drupal_get_form('booking_stripe_form', $person, $invoiceid, $net_amount_owing, $button_text);
  return drupal_render($payment_form);
}

function booking_stripe_form($node, &$form_state, $person, $invoiceid, $net_amount_owing, $button_text) {
  global $event;
  $settings = array();
  $form = array();

  //set some values for our internal stripe library to help process the form
  //these will be used by the attached js from booking-strip library to identify which parts of the form to process
  $setting['booking_stripe'] = array(
    'pubkey' => _booking_get_stripe_public_key(),
    'form_selector' => str_replace('_', '-', __FUNCTION__),
    'name' => $event->booking_eventname,
    'image' => variable_get('booking_stripe_logo', ''),
    'payment_button_label' => '{{amount}} (plus fees)',
  );

  //attach settings and javascript to the form
  $form['#attached'] = array(
    'js' => array(
      array('data' => $setting, 'type' => 'setting'),
    ),
    'library' => array(
      array('booking', 'booking-stripe'),
    ),
  );

  //paypal specific settings
  $vars = array(
    'nid' => $person->nid,
    'email' => $person->booking_email,
    'description' => $event->booking_eventname . ' ' . $person->booking_price_descrip,
    'invoice' => $invoiceid,
    'amount' => $net_amount_owing,
    'gross_amount' => number_format(_booking_add_stripe_fees($net_amount_owing, $person->booking_country), 2, '.', ''),
    'foreign_gross_amount' => number_format(_booking_add_stripe_fees($net_amount_owing, 'FakeCountry'), 2, '.', ''),
    'last_name' => $person->booking_lastname,
    'first_name' => $person->booking_firstname,
    'uuid' => $person->booking_tempid,
    'token_id' => '',
    'token_email' => '',
    'token_client_ip' => '',
    'card_brand' => '',
    'card_country' => '',
    'card_cvc_check' => '',
    'card_address_zip_check' => '',
  );

  //turn the array into a form
  foreach($vars as $name => $value) {
    $form[$name] = array(
      '#type'  => 'hidden',
      '#value' => $value,
    );
  };
  
  $form['submit'] = array(
    '#id' => 'stripe-submit',
    '#type' => 'button',
    '#value' => t($button_text),
  );
  $form['#after_build'][] = 'booking_stripe_add_final_validation';
  
  //watchdog('booking', 'Booking Balance payment: @info', array ('@info' => var_export($form, TRUE)));
  return $form;
}

/**
 * Tries to add final validation after all else has been added through alters.
 */
function booking_stripe_add_final_validation($form) {
  $form['#validate'][] = 'booking_stripe_validate_form_payment';
  return $form;
}

/**
 * Form validation callback.
 */
function booking_stripe_checkout_form_validate($form, &$form_state) {
  // Validate normal form elements as needed.
}

/**
 * Processes the stripe payment.
 *
 * We do this here so that if the payment fails,
 * we're still in a validation stage and can return
 * early.  If success, we'll pass the charge on
 * to the submission callback.
 */
function booking_stripe_validate_form_payment($form, &$form_state) {
  global $event;

  if($errors = form_get_errors()) {
    //@todo log an error via watchdog
    return;
  }

  $path = libraries_get_path('stripe');
  require_once($path . '/init.php');
  \Stripe\Stripe::setApiKey(_booking_get_stripe_private_key());

  //get values from original form
  //@todo sanitise this input  
  $token = (isset($form_state['input']['token_id']) ? $form_state['input']['token_id'] : '');
  $amount = (isset($form_state['input']['gross_amount']) ? $form_state['input']['gross_amount'] : '');
  $invoice = (isset($form_state['input']['invoice']) ? $form_state['input']['invoice'] : '');
  $nid = (isset($form_state['input']['nid']) ? $form_state['input']['nid'] : '');
  $tempid= (isset($form_state['input']['uuid']) ? $form_state['input']['uuid'] : '');
  $last_name = (isset($form_state['input']['last_name']) ? $form_state['input']['last_name'] : '');
  $first_name = (isset($form_state['input']['first_name']) ? $form_state['input']['first_name'] : '');
  $card_brand = (isset($form_state['input']['card_brand']) ? $form_state['input']['card_brand'] : '');
  $card_country = (isset($form_state['input']['card_country']) ? $form_state['input']['card_country'] : '');

  //if card issuer is american express then the transaction fee charged should be the international rate
  if ($card_brand === 'American Express') {
    $person = node_load($nid);
    $amount = (isset($form_state['input']['foreign_gross_amount']) ? $form_state['input']['foreign_gross_amount'] : $amount);
    watchdog('booking_debug', "Detected Amex card use, setting amount to !amount", array('!amount' => $amount));
  }
  //if card is issued from a different country then apply the international rate also
  //@todo figure out a better way of matching country name to country code
  // probably via https://api.drupal.org/api/drupal/includes%21locale.inc/function/country_get_list/7.x
  //NOTE! This will result in incorrect charge amounts when using the test API due to a stripe bug
  //since the australian test card number gets charged 2.9% instead of 1.75%
  elseif (variable_get('booking_default_country', 'Australia') === 'Australia' && $card_country !== 'AU') {
    $person = node_load($nid);
    $amount = (isset($form_state['input']['foreign_gross_amount']) ? $form_state['input']['foreign_gross_amount'] : $amount);
    watchdog('booking_debug', "Detected foreign card use (country !country), setting amount to !amount", 
      array('!country' => $card_country, '!amount' => $amount));
  }

  // Create the charge on Stripe's servers - this will charge the user's card
  try {
    $charge = \Stripe\Charge::create(array(
      "amount" => $amount * 100,
      "currency" => "aud",
      "card" => $token,
      "statement_descriptor" => substr($event->booking_eventname, 0, 21), //this field is limited to 22 characters
      "expand" => array('balance_transaction'),
      "description" => $form_state['input']['description'],
      "receipt_email" => $form_state['input']['email'],
      "metadata" => array(
          "invoice" => $invoice,
          "nid" => $nid,
          "last_name" => $last_name,
          "first_name" => $first_name,
      ),
    ));
    watchdog('booking_debug', "<pre>Stripe payment charge results:\n@info</pre>", array('@info' => print_r( $charge->toJSON(), true)));    
    if ($charge && $charge->paid) {
      //watchdog('booking_debug', 'Charge created successfully');
      _booking_process_stripe_payment($charge, $token);
      //$form_state['stripeform_charge'] = $charge;
      // @todo call _booking_process_stripe_payment to store payment 
      drupal_goto('bookingfinal/' . $tempid);
    }
    else {
      watchdog('booking', 'Charge was not created successfully');
      drupal_set_message('Card does not seem to have been charged successfully. Please try again', 'error');
    }
  } 
  catch(\Stripe\Error\Card $e) {
    $e_json = $e->getJsonBody();
    $error = $e_json['error'];
    watchdog('booking', "<pre>Detected exception processing Stripe payment (!message)\n@info</pre>", 
      array('!message' => $e->getMessage(), '@info' => var_dump( $e->getTraceAsString() )));
    drupal_set_message($e->getMessage(), 'error');
  } 
  catch (\Stripe\Error\ApiConnection $e) {
    watchdog('booking', "<pre>Detected exception processing Stripe payment (!message)\n@info</pre>", 
      array('!message' => $e->getMessage(), '@info' => var_dump( $e->getTraceAsString() )));
    drupal_set_message($e->getMessage(), 'error');
  } 
  catch (\Stripe\Error\Api $e) {
    watchdog('booking', "<pre>Detected exception processing Stripe payment (!message)\n@info</pre>", 
      array('!message' => $e->getMessage(), '@info' => var_dump( $e->getTraceAsString() )));
    drupal_set_message($e->getMessage(), 'error');
  }
  catch (\Stripe\Exception\CardException $e) {
    watchdog('booking', "<pre>Detected exception processing Stripe payment (!message)\n@info</pre>", 
      array('!message' => $e->getMessage(), '@info' => var_dump( $e->getTraceAsString() )));
    drupal_set_message($e->getMessage(), 'error');    
  }
}

function _booking_process_stripe_payment(&$charge, $token) {
  global $event;  
  $balance_payment = false;
  $amount_owing = 0;
  //$invoice = $data->metadata;

  //verify the status of the charge 
  if (empty($charge->status) || ($charge->status != 'succeeded')) {
    $successful = FALSE;
  }
  else {
    $successful = TRUE;
  }
  
  //extract the person node id from the invoice
  $pos = strpos($charge->metadata->invoice, "_");
  if (($pos === false) || ($pos == 0)) {
    watchdog('booking', 'Unable to process payment with invalid invoice information: !id', array('!id' => $charge->metadata->invoice), WATCHDOG_ERROR);
    return;
  }

  //get the part of the invoice up to the first underscore
  $nid = substr($charge->metadata->invoice, 0, $pos);  
  //get the data between the first and second underscore
  $eid = substr($charge->metadata->invoice, $pos + 1, strrpos($charge->metadata->invoice, "_") - $pos - 1);
  
  if (substr($eid,0,3) == "bal") {
    $balance_payment = true;
    watchdog('booking_debug', 'Balance payment via stripe for user with node id: !id and status !status.', 
      array('!id' => $nid, '!status' => $charge->status));  
  }
  else {
     watchdog('booking_debug', 'Initial payment via stripe for user with node id: !id and status !status.', 
      array('!id' => $nid, '!status' => $charge->status));     
  }

  //this shouldn't ever happen, since stripe is sending this notification synchronously
  //but just in case, check for an existing transaction that matches this one
	$duplicate_check = db_query("SELECT payid, booking_person_nid FROM {booking_payment} where booking_ipn_track_id = :ipn_id ", 
                              array(':ipn_id' => $charge->id))->fetchObject();    

  if ($duplicate_check) {
    watchdog('booking', 'Detected duplicate stripe transaction notifications for transaction id !id, registration id !nid', 
      array('!id' => $charge->id, '!nid' => $nid), WATCHDOG_ERROR);
    return;
  }

  $gross_amount = $charge->amount / 100;
  $result = db_insert('booking_payment')
    ->fields(array(
      'booking_person_nid' => $nid,
      'booking_eventid' => $event->eid,
      'booking_mc_gross' => $gross_amount,
      'booking_mc_currency' => $charge->balance_transaction->currency,
      'booking_mc_fee' => $charge->balance_transaction->fee / 100,
      'booking_invoice' => $charge->metadata->invoice,
      'booking_payer_id' => $charge->source->id,
      'booking_payment_date' => $charge->created,
      'booking_payment_status' => $charge->status,
      'booking_first_name' => $charge->metadata->first_name,
      'booking_last_name' => $charge->metadata->last_name,
      'booking_buyer_email' => $charge->receipt_email,
      'booking_item_name' => $charge->description,
      'booking_ipn_track_id' => $charge->id,
      'booking_stripe_response' => $charge->toJSON(),
    ))
    ->execute();

	//Get the person's info so we can update their total amount paid and booking status
	$person = node_load($nid);	

	//check if we found a person matching this payment
	if ($person) {
 		watchdog('booking', 'Found matching user with node id: !id; event id: !eid; existing payment !payment', 
		 array('!id' => $nid, '!eid' => $eid, '!payment' => $person->booking_amount_paid));
		 _booking_process_person_payment($person, $gross_amount, $balance_payment);
	} 
	else { 
		//couldn't find a matching nid for this invoice
		watchdog('booking', "Unable to process payment for user with node id: '!id'", array('!id' => $nid), WATCHDOG_ERROR);  	
		//db_query("UPDATE {booking_person} SET booking_tempid='' WHERE nid = %d", $nid);
	}
}