silverstripe-multiform/code/model/MultiForm.php
2015-11-23 22:53:45 +13:00

670 lines
21 KiB
PHP

<?php
/**
* MultiForm manages the loading of single form steps, and acts as a state
* machine that connects to a {@link MultiFormSession} object as a persistence
* layer.
*
* CAUTION: If you're using controller permission control,
* you have to allow the following methods:
*
* <code>
* private static $allowed_actions = array('next','prev');
* </code>
*
* @package multiform
*/
abstract class MultiForm extends Form {
/**
* A session object stored in the database, to identify and store
* data for this MultiForm instance.
*
* @var MultiFormSession
*/
protected $session;
/**
* The current encrypted MultiFormSession identification.
*
* @var string
*/
protected $currentSessionHash;
/**
* Defines which subclass of {@link MultiFormStep} should be the first
* step in the multi-step process.
*
* @var string Classname of a {@link MultiFormStep} subclass
*/
public static $start_step;
/**
* Set the casting for these fields.
*
* @var array
*/
private static $casting = array(
'CompletedStepCount' => 'Int',
'TotalStepCount' => 'Int',
'CompletedPercent' => 'Float'
);
/**
* These fields are ignored when saving the raw form data into session.
* This ensures only field data is saved, and nothing else that's useless
* or potentially dangerous.
*
* @var array
*/
public static $ignored_fields = array(
'url',
'executeForm',
'MultiFormSessionID',
'SecurityID'
);
/**
* Any of the actions defined in this variable are exempt from
* being validated.
*
* This is most useful for the "Back" (action_prev) action, as
* you typically don't validate the form when the user is going
* back a step.
*
* @var array
*/
public static $actions_exempt_from_validation = array(
'action_prev'
);
/**
* @var string
*/
protected $displayLink;
/**
* Flag which is being used in getAllStepsRecursive() to allow adding the completed flag on the steps
*
* @var boolean
*/
protected $currentStepHasBeenFound = false;
/**
* Start the MultiForm instance.
*
* @param Controller instance $controller Controller this form is created on
* @param string $name The form name, typically the same as the method name
*/
public function __construct($controller, $name) {
// First set the controller and name manually so they are available for
// field construction.
$this->controller = $controller;
$this->name = $name;
// Set up the session for this MultiForm instance
$this->setSession();
// Get the current step available (Note: either returns an existing
// step or creates a new one if none available)
$currentStep = $this->getCurrentStep();
// Set the step returned above as the current step
$this->setCurrentStep($currentStep);
// Set the form of the step to this form instance
$currentStep->setForm($this);
// Set up the fields for the current step
$fields = $currentStep->getFields();
// Set up the actions for the current step
$actions = $this->actionsFor($currentStep);
// Set up validation (if necessary)
$validator = null;
$applyValidation = true;
$actionNames = static::$actions_exempt_from_validation;
if( $actionNames ) {
foreach( $actionNames as $exemptAction) {
if(!empty($_REQUEST[$exemptAction])) {
$applyValidation = false;
break;
}
}
}
// Apply validation if the current step requires validation (is not exempt)
if($applyValidation) {
if($currentStep->getValidator()) {
$validator = $currentStep->getValidator();
}
}
// Give the fields, actions, and validation for the current step back to the parent Form class
parent::__construct($controller, $name, $fields, $actions, $validator);
// Set a hidden field in our form with an encrypted hash to identify this session.
$this->fields->push(new HiddenField('MultiFormSessionID', false, $this->session->Hash));
// If there is saved data for the current step, we load it into the form it here
//(CAUTION: loadData() MUST unserialize first!)
if($data = $currentStep->loadData()) {
$this->loadDataFrom($data);
}
// Disable security token - we tie a form to a session ID instead
$this->disableSecurityToken();
}
/**
* Accessor method to $this->controller.
*
* @return Controller this MultiForm was instanciated on.
*/
public function getController() {
return $this->controller;
}
/**
* Get the current step.
*
* If StepID has been set in the URL, we attempt to get that record
* by the ID. Otherwise, we check if there's a current step ID in
* our session record. Failing those cases, we assume that the form has
* just been started, and so we create the first step and return it.
*
* @return MultiFormStep subclass
*/
public function getCurrentStep() {
$startStepClass = static::$start_step;
// Check if there was a start step defined on the subclass of MultiForm
if(!isset($startStepClass)) user_error('MultiForm::init(): Please define a $start_step on ' . $this->class, E_USER_ERROR);
// Determine whether we use the current step, or create one if it doesn't exist
$currentStep = null;
if(isset($_GET['StepID'])) {
$stepID = (int)$_GET['StepID'];
$currentStep = DataObject::get_one('MultiFormStep', "\"SessionID\" = {$this->session->ID} AND \"ID\" = {$stepID}");
} elseif($this->session->CurrentStepID) {
$currentStep = $this->session->CurrentStep();
}
// Always fall back to creating a new step (in case the session or request data is invalid)
if(!$currentStep || !$currentStep->ID) {
$currentStep = Object::create($startStepClass);
$currentStep->SessionID = $this->session->ID;
$currentStep->write();
$this->session->CurrentStepID = $currentStep->ID;
$this->session->write();
$this->session->flushCache();
}
if($currentStep) $currentStep->setForm($this);
return $currentStep;
}
/**
* Set the step passed in as the current step.
*
* @param MultiFormStep $step A subclass of MultiFormStep
* @return boolean The return value of write()
*/
protected function setCurrentStep($step) {
$this->session->CurrentStepID = $step->ID;
$step->setForm($this);
return $this->session->write();
}
/**
* Accessor method to $this->session.
*
* @return MultiFormSession
*/
public function getSession() {
return $this->session;
}
/**
* Set up the session.
*
* If MultiFormSessionID isn't set, we assume that this is a new
* multiform that requires a new session record to be created.
*
* @TODO Fix the fact you can continually refresh and create new records
* if MultiFormSessionID isn't set.
*
* @TODO Not sure if we should bake the session stuff directly into MultiForm.
* Perhaps it would be best dealt with on a separate class?
*/
protected function setSession() {
$this->session = $this->getCurrentSession();
// If there was no session found, create a new one instead
if(!$this->session) {
$this->session = new MultiFormSession();
}
// Create encrypted identification to the session instance if it doesn't exist
if(!$this->session->Hash) {
$this->session->Hash = sha1($this->session->ID . '-' . microtime());
$this->session->write();
}
}
/**
* Set the currently used encrypted hash to identify
* the MultiFormSession.
*
* @param string $hash Encrypted identification to session
*/
public function setCurrentSessionHash($hash) {
$this->currentSessionHash = $hash;
$this->setSession();
}
/**
* Return the currently used {@link MultiFormSession}
* @return MultiFormSession|boolean FALSE
*/
public function getCurrentSession() {
if(!$this->currentSessionHash) {
$this->currentSessionHash = $this->controller->request->getVar('MultiFormSessionID');
if(!$this->currentSessionHash) {
return false;
}
}
$this->session = MultiFormSession::get()->filter(array(
"Hash" => $this->currentSessionHash,
"IsComplete" => 0
))->first();
return $this->session;
}
/**
* Get all steps saved in the database for the currently active session,
* in the order they were saved, oldest to newest (automatically ordered by ID).
* If you want a full chain of steps regardless if they've already been saved
* to the database, use {@link getAllStepsLinear()}.
*
* @param String $filter SQL WHERE statement
* @return DataObjectSet|boolean A set of MultiFormStep subclasses
*/
function getSavedSteps($filter = null) {
$filter .= ($filter) ? ' AND ' : '';
$filter .= sprintf("\"SessionID\" = '%s'", $this->session->ID);
return DataObject::get('MultiFormStep', $filter);
}
/**
* Get a step which was previously saved to the database in the current session.
* Caution: This might cause unexpected behaviour if you have multiple steps
* in your chain with the same classname.
*
* @param string $className Classname of a {@link MultiFormStep} subclass
* @return MultiFormStep
*/
function getSavedStepByClass($className) {
return DataObject::get_one(
'MultiFormStep',
sprintf("\"SessionID\" = '%s' AND \"ClassName\" = '%s'",
$this->session->ID,
Convert::raw2sql($className)
)
);
}
/**
* Build a FieldList of the FormAction fields for the given step.
*
* If the current step is the final step, we push in a submit button, which
* calls the action {@link finish()} to finalise the submission. Otherwise,
* we push in a next button which calls the action {@link next()} to determine
* where to go next in our step process, and save any form data collected.
*
* If there's a previous step (a step that has the current step as it's next
* step class), then we allow a previous button, which calls the previous action
* to determine which step to go back to.
*
* If there are any extra actions defined in MultiFormStep->getExtraActions()
* then that set of actions is appended to the end of the actions FieldSet we
* have created in this method.
*
* @param $currentStep Subclass of MultiFormStep
* @return FieldList of FormAction objects
*/
function actionsFor($step) {
// Create default multi step actions (next, prev), and merge with extra actions, if any
$actions = (class_exists('FieldList')) ? new FieldList() : new FieldSet();
// If the form is at final step, create a submit button to perform final actions
// The last step doesn't have a next button, so add that action to any step that isn't the final one
if($step->isFinalStep()) {
$actions->push(new FormAction('finish', $step->getSubmitText()));
} else {
$actions->push(new FormAction('next', $step->getNextText()));
}
// If there is a previous step defined, add the back button
if($step->getPreviousStep() && $step->canGoBack()) {
// If there is a next step, insert the action before the next action
if($step->getNextStep()) {
$actions->insertBefore(new FormAction('prev', $step->getPrevText()), 'action_next');
// Assume that this is the last step, insert the action before the finish action
} else {
$actions->insertBefore(new FormAction('prev', $step->getPrevText()), 'action_finish');
}
}
// Merge any extra action fields defined on the step
$actions->merge($step->getExtraActions());
return $actions;
}
/**
* Return a rendered version of this form, with a specific template.
* Looks through the step ancestory templates (MultiFormStep, current step
* subclass template) to see if one is available to render the form with. If
* any of those don't exist, look for a default Form template to render
* with instead.
*
* @return SSViewer object to render the template with
*/
function forTemplate() {
$return = $this->renderWith(array(
$this->getCurrentStep()->class,
'MultiFormStep',
$this->class,
'MultiForm',
'Form'
));
$this->clearMessage();
return $return;
}
/**
* This method saves the data on the final step, after submitting.
* It should always be overloaded with parent::finish($data, $form)
* so you can create your own functionality which handles saving
* of all the data collected through each step of the form.
*
* @param array $data The request data returned from the form
* @param object $form The form that the action was called on
*/
public function finish($data, $form) {
// Save the form data for the current step
$this->save($data);
if(!$this->getCurrentStep()->isFinalStep()) {
$this->controller->redirectBack();
return false;
}
if(!$this->getCurrentStep()->validateStep($data, $form)) {
Session::set("FormInfo.{$form->FormName()}.data", $form->getData());
$this->controller->redirectBack();
return false;
}
}
/**
* Determine what to do when the next action is called.
*
* Saves the current step session data to the database, creates the
* new step based on getNextStep() of the current step (or fetches
* an existing one), resets the current step to the next step,
* then redirects to the newly set step.
*
* @param array $data The request data returned from the form
* @param object $form The form that the action was called on
*/
public function next($data, $form) {
// Save the form data for the current step
$this->save($form->getData());
// Get the next step class
$nextStepClass = $this->getCurrentStep()->getNextStep();
if(!$nextStepClass) {
$this->controller->redirectBack();
return false;
}
// Perform custom step validation (use MultiFormStep->getValidator() for
// built-in functionality). The data needs to be manually saved on error
// so the form is re-populated.
if(!$this->getCurrentStep()->validateStep($data, $form)) {
Session::set("FormInfo.{$form->FormName()}.data", $form->getData());
$this->controller->redirectBack();
return false;
}
// validation succeeded so we reset it to remove errors and messages
$this->resetValidation();
// Determine whether we can use a step already in the DB, or have to create a new one
if(!$nextStep = DataObject::get_one($nextStepClass, "\"SessionID\" = {$this->session->ID}")) {
$nextStep = Object::create($nextStepClass);
$nextStep->SessionID = $this->session->ID;
$nextStep->write();
}
// Set the next step found as the current step
$this->setCurrentStep($nextStep);
// Redirect to the next step
$this->controller->redirect($nextStep->Link());
}
/**
* Determine what to do when the previous action is called.
*
* Retrieves the previous step class, finds the record for that
* class in the DB, and sets the current step to that step found.
* Finally, it redirects to that step.
*
* @param array $data The request data returned from the form
* @param object $form The form that the action was called on
*/
public function prev($data, $form) {
// Save the form data for the current step
$this->save($form->getData());
// Get the previous step class
$prevStepClass = $this->getCurrentStep()->getPreviousStep();
if(!$prevStepClass && !$this->getCurrentStep()->canGoBack()) {
$this->controller->redirectBack();
return false;
}
// Get the previous step of the class instance returned from $currentStep->getPreviousStep()
$prevStep = DataObject::get_one($prevStepClass, "\"SessionID\" = {$this->session->ID}");
// Set the current step as the previous step
$this->setCurrentStep($prevStep);
// Redirect to the previous step
$this->controller->redirect($prevStep->Link());
}
/**
* Save the raw data given back from the form into session.
*
* Take the submitted form data for the current step, removing
* any key => value pairs that shouldn't be saved, then saves
* the data into the session.
*
* @param array $data An array of data to save
*/
protected function save($data) {
$currentStep = $this->getCurrentStep();
if(is_array($data)) {
foreach($data as $field => $value) {
if(in_array($field, static::$ignored_fields)) {
unset($data[$field]);
}
}
$currentStep->saveData($data);
}
return;
}
// ############ Misc ############
/**
* Add the MultiFormSessionID variable to the URL on form submission.
* This is a means to persist the session, by adding it's identification
* to the URL, which ties it back to this MultiForm instance.
*
* @return string
*/
function FormAction() {
$action = parent::FormAction();
$action .= (strpos($action, '?')) ? '&amp;' : '?';
$action .= "MultiFormSessionID={$this->session->Hash}";
return $action;
}
/**
* Returns the link to the page where the form is displayed. The user is
* redirected to this link with a session param after each step is
* submitted.
*
* @return string
*/
public function getDisplayLink() {
return $this->displayLink ? $this->displayLink : Controller::curr()->Link();
}
/**
* Set the link to the page on which the form is displayed.
*
* The link defaults to the controllers current link. However if the form
* is displayed inside an action the display link must be explicitly set.
*
* @param string $link
*/
public function setDisplayLink($link) {
$this->displayLink = $link;
}
/**
* Determine the steps to show in a linear fashion, starting from the
* first step. We run {@link getAllStepsRecursive} passing the steps found
* by reference to get a listing of the steps.
*
* @return DataObjectSet of MultiFormStep instances
*/
public function getAllStepsLinear() {
$stepsFound = (class_exists('ArrayList')) ? new ArrayList() : new DataObjectSet();
$firstStep = DataObject::get_one(static::$start_step, "\"SessionID\" = {$this->session->ID}");
$firstStep->LinkingMode = ($firstStep->ID == $this->getCurrentStep()->ID) ? 'current' : 'link';
$firstStep->addExtraClass('completed');
$firstStep->setForm($this);
$stepsFound->push($firstStep);
// mark the further steps as non-completed if the first step is the current
if ($firstStep->ID == $this->getCurrentStep()->ID) $this->currentStepHasBeenFound = true;
$this->getAllStepsRecursive($firstStep, $stepsFound);
return $stepsFound;
}
/**
* Recursively run through steps using the getNextStep() method on each step
* to determine what the next step is, gathering each step along the way.
* We stop on the last step, and return the results.
* If a step in the chain was already saved to the database in the current
* session, its used - otherwise a singleton of this step is used.
* Caution: Doesn't consider branching for steps which aren't in the database yet.
*
* @param $step Subclass of MultiFormStep to find the next step of
* @param $stepsFound $stepsFound DataObjectSet reference, the steps found to call back on
* @return DataObjectSet of MultiFormStep instances
*/
protected function getAllStepsRecursive($step, &$stepsFound) {
// Find the next step to the current step, the final step has no next step
if(!$step->isFinalStep()) {
if($step->getNextStep()) {
// Is this step in the DB? If it is, we use that
$nextStep = $step->getNextStepFromDatabase();
if(!$nextStep) {
// If it's not in the DB, we use a singleton instance of it instead -
// - this step hasn't been accessed yet
$nextStep = singleton($step->getNextStep());
}
// once the current steps has been found we won't add the completed class anymore.
if ($nextStep->ID == $this->getCurrentStep()->ID) $this->currentStepHasBeenFound = true;
$nextStep->LinkingMode = ($nextStep->ID == $this->getCurrentStep()->ID) ? 'current' : 'link';
// add the completed class
if (!$this->currentStepHasBeenFound) $nextStep->addExtraClass('completed');
$nextStep->setForm($this);
// Add the array data, and do a callback
$stepsFound->push($nextStep);
$this->getAllStepsRecursive($nextStep, $stepsFound);
}
// Once we've reached the final step, we just return what we've collected
} else {
return $stepsFound;
}
}
/**
* Number of steps already completed (excluding currently started step).
* The way we determine a step is complete is to check if it has the Data
* field filled out with a serialized value, then we know that the user has
* clicked next on the given step, to proceed.
*
* @TODO Not sure if it's entirely appropriate to check if Data is set as a
* way to determine a step is "completed".
*
* @return int
*/
public function getCompletedStepCount() {
$steps = DataObject::get('MultiFormStep', "\"SessionID\" = {$this->session->ID} && \"Data\" IS NOT NULL");
return $steps ? $steps->Count() : 0;
}
/**
* Total number of steps in the shortest path (only counting straight path without any branching)
* The way we determine this is to check if each step has a next_step string variable set. If it's
* anything else (like an array, for defining multiple branches) then it gets counted as a single step.
*
* @return int
*/
public function getTotalStepCount() {
return $this->getAllStepsLinear() ? $this->getAllStepsLinear()->Count() : 0;
}
/**
* Percentage of steps completed (excluding currently started step)
*
* @return float
*/
public function getCompletedPercent() {
return (float)$this->getCompletedStepCount() * 100 / $this->getTotalStepCount();
}
}