wizard.inc

<?php


/**
 * @file
 * CTools' multi-step form wizard tool.
 *
 * This tool enables the creation of multi-step forms that go from one
 * form to another. The forms themselves can allow branching if they
 * like, and there are a number of configurable options to how
 * the wizard operates.
 *
 * The wizard can also be friendly to ajax forms, such as when used
 * with the modal tool.
 *
 * The wizard provides callbacks throughout the process, allowing the
 * owner to control the flow. The general flow of what happens is:
 *
 * Generate a form
 * submit a form
 * based upon button clicked, 'finished', 'next form', 'cancel' or 'return'.
 *
 * Each action has its own callback, so cached objects can be modifed and or
 * turned into real objects. Each callback can make decisions about where to
 * go next if it wishes to override the default flow.
 */

/**
 * Display a multi-step form.
 *
 * Aside from the addition of the $form_info which contains an array of
 * information and configuration so the multi-step wizard can do its thing,
 * this function works a lot like drupal_build_form.
 *
 * Remember that the form builders for this form will receive
 * &$form, &$form_state, NOT just &$form_state and no additional args.
 *
 * @param $form_info
 *   An array of form info. @todo document the array.
 * @param $step
 *   The current form step.
 * @param &$form_state
 *   The form state array; this is a reference so the caller can get back
 *   whatever information the form(s) involved left for it.
 */
function ctools_wizard_multistep_form($form_info, $step, &$form_state) {
    // Make sure 'wizard' always exists for the form when dealing
    // with form caching.
    ctools_form_include($form_state, 'wizard');
    // Allow order array to be optional.
    if (empty($form_info['order'])) {
        foreach ($form_info['forms'] as $step_id => $params) {
            $form_info['order'][$step_id] = $params['title'];
        }
    }
    if (!isset($step)) {
        $keys = array_keys($form_info['order']);
        $step = array_shift($keys);
    }
    ctools_wizard_defaults($form_info);
    // If automated caching is enabled, ensure that everything is as it
    // should be.
    if (!empty($form_info['auto cache'])) {
        // If the cache mechanism hasn't been set, default to the simple
        // mechanism and use the wizard ID to ensure uniqueness so cache
        // objects don't stomp on each other.
        if (!isset($form_info['cache mechanism'])) {
            $form_info['cache mechanism'] = 'simple::wizard::' . $form_info['id'];
        }
        // If not set, default the cache key to the wizard ID. This is often
        // a unique ID of the object being edited or similar.
        if (!isset($form_info['cache key'])) {
            $form_info['cache key'] = $form_info['id'];
        }
        // If not set, default the cache location to storage. This is often
        // somnething like 'conf'.
        if (!isset($form_info['cache location'])) {
            $form_info['cache location'] = 'storage';
        }
        // If absolutely nothing was set for the cache area to work on.
        if (!isset($form_state[$form_info['cache location']])) {
            ctools_include('cache');
            $form_state[$form_info['cache location']] = ctools_cache_get($form_info['cache mechanism'], $form_info['cache key']);
        }
    }
    $form_state['step'] = $step;
    $form_state['form_info'] = $form_info;
    // Ensure we have form information for the current step.
    if (!isset($form_info['forms'][$step])) {
        return;
    }
    // Ensure that whatever include file(s) were requested by the form info are
    // actually included.
    $info = $form_info['forms'][$step];
    if (!empty($info['include'])) {
        if (is_array($info['include'])) {
            foreach ($info['include'] as $file) {
                ctools_form_include_file($form_state, $file);
            }
        }
        else {
            ctools_form_include_file($form_state, $info['include']);
        }
    }
    // This tells drupal_build_form to apply our wrapper to the form. It
    // will give it buttons and the like.
    $form_state['wrapper_callback'] = 'ctools_wizard_wrapper';
    if (!isset($form_state['rerender'])) {
        $form_state['rerender'] = FALSE;
    }
    $form_state['no_redirect'] = TRUE;
    $output = drupal_build_form($info['form id'], $form_state);
    if (empty($form_state['executed']) || !empty($form_state['rerender'])) {
        if (empty($form_state['title']) && !empty($info['title'])) {
            $form_state['title'] = $info['title'];
        }
        if (!empty($form_state['ajax render'])) {
            // Any include files should already be included by this point:
            return $form_state['ajax render']($form_state, $output);
        }
        // Automatically use the modal tool if set to true.
        if (!empty($form_state['modal']) && empty($form_state['modal return'])) {
            ctools_include('modal');
            // This overwrites any previous commands.
            $form_state['commands'] = ctools_modal_form_render($form_state, $output);
        }
    }
    if (!empty($form_state['executed'])) {
        // We use the plugins get_function format because it's powerful and
        // not limited to just functions.
        ctools_include('plugins');
        if (isset($form_state['clicked_button']['#wizard type'])) {
            $type = $form_state['clicked_button']['#wizard type'];
            // If we have a callback depending upon the type of button that was
            // clicked, call it.
            if ($function = ctools_plugin_get_function($form_info, "{$type} callback")) {
                $function($form_state);
            }
            // If auto-caching is on, we need to write the cache on next and
            // clear the cache on finish.
            if (!empty($form_info['auto cache'])) {
                if ($type == 'next') {
                    ctools_include('cache');
                    ctools_cache_set($form_info['cache mechanism'], $form_info['cache key'], $form_state[$form_info['cache location']]);
                }
                elseif ($type == 'finish') {
                    ctools_include('cache');
                    ctools_cache_clear($form_info['cache mechanism'], $form_info['cache key']);
                }
            }
            // Set a couple of niceties:
            if ($type == 'finish') {
                $form_state['complete'] = TRUE;
            }
            if ($type == 'cancel') {
                $form_state['cancel'] = TRUE;
            }
            // If the modal is in use, some special code for it:
            if (!empty($form_state['modal']) && empty($form_state['modal return'])) {
                if ($type != 'next') {
                    // Automatically dismiss the modal if we're not going to another form.
                    ctools_include('modal');
                    $form_state['commands'][] = ctools_modal_command_dismiss();
                }
            }
        }
        if (empty($form_state['ajax'])) {
            // redirect, if one is set.
            if ($form_state['redirect']) {
                if (is_array($form_state['redirect'])) {
                    call_user_func_array('drupal_goto', $form_state['redirect']);
                }
                else {
                    drupal_goto($form_state['redirect']);
                }
            }
        }
        elseif (isset($form_state['ajax next'])) {
            // Clear a few items off the form state so we don't double post:
            $next = $form_state['ajax next'];
            unset($form_state['ajax next']);
            unset($form_state['executed']);
            unset($form_state['post']);
            unset($form_state['next']);
            return ctools_wizard_multistep_form($form_info, $next, $form_state);
        }
        // If the callbacks wanted to do something besides go to the next form,
        // it needs to have set $form_state['commands'] with something that can
        // be rendered.
    }
    // Render ajax commands if we have any.
    if (isset($form_state['ajax']) && isset($form_state['commands']) && empty($form_state['modal return'])) {
        return ajax_render($form_state['commands']);
    }
    // Otherwise, return the output.
    return $output;
}

/**
 * Provide a wrapper around another form for adding multi-step information.
 */
function ctools_wizard_wrapper($form, &$form_state) {
    $form_info =& $form_state['form_info'];
    $info = $form_info['forms'][$form_state['step']];
    // Determine the next form from this step.
    // Create a form trail if we're supposed to have one.
    $trail = array();
    $previous = TRUE;
    foreach ($form_info['order'] as $id => $title) {
        if ($id == $form_state['step']) {
            $previous = FALSE;
            $class = 'wizard-trail-current';
        }
        elseif ($previous) {
            $not_first = TRUE;
            $class = 'wizard-trail-previous';
            $form_state['previous'] = $id;
        }
        else {
            $class = 'wizard-trail-next';
            if (!isset($form_state['next'])) {
                $form_state['next'] = $id;
            }
            if (empty($form_info['show trail'])) {
                break;
            }
        }
        if (!empty($form_info['show trail'])) {
            if (!empty($form_info['free trail'])) {
                // ctools_wizard_get_path() returns results suitable for
                // $form_state['redirect] which can only be directly used in
                // drupal_goto. We have to futz a bit with it.
                $path = ctools_wizard_get_path($form_info, $id);
                $options = array();
                if (!empty($path[1])) {
                    $options = $path[1];
                }
                $title = l($title, $path[0], $options);
            }
            $trail[] = '<span class="' . $class . '">' . $title . '</span>';
        }
    }
    // Display the trail if instructed to do so.
    if (!empty($form_info['show trail'])) {
        ctools_add_css('wizard');
        $form['ctools_trail'] = array(
            '#markup' => theme(array(
                'ctools_wizard_trail__' . $form_info['id'],
                'ctools_wizard_trail',
            ), array(
                'trail' => $trail,
                'form_info' => $form_info,
            )),
            '#weight' => -1000,
        );
    }
    if (empty($form_info['no buttons'])) {
        // Ensure buttons stay on the bottom.
        $form['buttons'] = array(
            '#type' => 'actions',
            '#weight' => 1000,
        );
        $button_attributes = array();
        if (!empty($form_state['ajax']) && empty($form_state['modal'])) {
            $button_attributes = array(
                'class' => array(
                    'ctools-use-ajax',
                ),
            );
        }
        if (!empty($form_info['show back']) && isset($form_state['previous'])) {
            $form['buttons']['previous'] = array(
                '#type' => 'submit',
                '#value' => $form_info['back text'],
                '#next' => $form_state['previous'],
                '#wizard type' => 'next',
                '#weight' => -2000,
                '#limit_validation_errors' => array(),
                // Hardcode the submit so that it doesn't try to save data.
'#submit' => array(
                    'ctools_wizard_submit',
                ),
                '#attributes' => $button_attributes,
            );
            if (isset($form_info['no back validate']) || isset($info['no back validate'])) {
                $form['buttons']['previous']['#validate'] = array();
            }
        }
        // If there is a next form, place the next button.
        if (isset($form_state['next']) || !empty($form_info['free trail'])) {
            $form['buttons']['next'] = array(
                '#type' => 'submit',
                '#value' => $form_info['next text'],
                '#next' => !empty($form_info['free trail']) ? $form_state['step'] : $form_state['next'],
                '#wizard type' => 'next',
                '#weight' => -1000,
                '#attributes' => $button_attributes,
            );
        }
        // There are two ways the return button can appear. If this is not the
        // end of the form list (i.e, there is a next) then it's "update and return"
        // to be clear. If this is the end of the path and there is no next, we
        // call it 'Finish'.
        // Even if there is no direct return path (some forms may not want you
        // leaving in the middle) the final button is always a Finish and it does
        // whatever the return action is.
        if (!empty($form_info['show return']) && !empty($form_state['next'])) {
            $form['buttons']['return'] = array(
                '#type' => 'submit',
                '#value' => $form_info['return text'],
                '#wizard type' => 'return',
                '#attributes' => $button_attributes,
            );
        }
        elseif (empty($form_state['next']) || !empty($form_info['free trail'])) {
            $form['buttons']['return'] = array(
                '#type' => 'submit',
                '#value' => $form_info['finish text'],
                '#wizard type' => 'finish',
                '#attributes' => $button_attributes,
            );
        }
        // If we are allowed to cancel, place a cancel button.
        if (isset($form_info['cancel path']) && !isset($form_info['show cancel']) || !empty($form_info['show cancel'])) {
            $form['buttons']['cancel'] = array(
                '#type' => 'submit',
                '#value' => $form_info['cancel text'],
                '#wizard type' => 'cancel',
                // Hardcode the submit so that it doesn't try to save data.
'#limit_validation_errors' => array(),
                '#submit' => array(
                    'ctools_wizard_submit',
                ),
                '#attributes' => $button_attributes,
            );
        }
        // Set up optional validate handlers.
        $form['#validate'] = array();
        if (function_exists($info['form id'] . '_validate')) {
            $form['#validate'][] = $info['form id'] . '_validate';
        }
        if (isset($info['validate']) && function_exists($info['validate'])) {
            $form['#validate'][] = $info['validate'];
        }
        // Set up our submit handler after theirs. Since putting something here will
        // skip Drupal's autodetect, we autodetect for it.
        // We make sure ours is after theirs so that they get to change #next if
        // the want to.
        $form['#submit'] = array();
        if (function_exists($info['form id'] . '_submit')) {
            $form['#submit'][] = $info['form id'] . '_submit';
        }
        if (isset($info['submit']) && function_exists($info['submit'])) {
            $form['#submit'][] = $info['submit'];
        }
        $form['#submit'][] = 'ctools_wizard_submit';
    }
    if (!empty($form_state['ajax'])) {
        $params = ctools_wizard_get_path($form_state['form_info'], $form_state['step']);
        if (count($params) > 1) {
            $url = array_shift($params);
            $options = array();
            $keys = array(
                0 => 'query',
                1 => 'fragment',
            );
            foreach ($params as $key => $value) {
                if (isset($keys[$key]) && isset($value)) {
                    $options[$keys[$key]] = $value;
                }
            }
            $params = array(
                $url,
                $options,
            );
        }
        $form['#action'] = call_user_func_array('url', $params);
    }
    if (isset($info['wrapper']) && function_exists($info['wrapper'])) {
        $form = $info['wrapper']($form, $form_state);
    }
    if (isset($form_info['wrapper']) && function_exists($form_info['wrapper'])) {
        $form = $form_info['wrapper']($form, $form_state);
    }
    return $form;
}

/**
 * On a submit, go to the next form.
 */
function ctools_wizard_submit(&$form, &$form_state) {
    if (isset($form_state['clicked_button']['#wizard type'])) {
        $type = $form_state['clicked_button']['#wizard type'];
        // If AJAX enabled, we proceed slightly differently here.
        if (!empty($form_state['ajax'])) {
            if ($type == 'next') {
                $form_state['ajax next'] = $form_state['clicked_button']['#next'];
            }
        }
        else {
            if ($type == 'cancel' && isset($form_state['form_info']['cancel path'])) {
                $form_state['redirect'] = $form_state['form_info']['cancel path'];
            }
            elseif ($type == 'next') {
                $form_state['redirect'] = ctools_wizard_get_path($form_state['form_info'], $form_state['clicked_button']['#next']);
                if (!empty($_GET['destination'])) {
                    // We don't want drupal_goto redirect this request
                    // back. ctools_wizard_get_path ensures that the destination is
                    // carried over on subsequent pages.
                    unset($_GET['destination']);
                }
            }
            elseif (isset($form_state['form_info']['return path'])) {
                $form_state['redirect'] = $form_state['form_info']['return path'];
            }
            elseif ($type == 'finish' && isset($form_state['form_info']['cancel path'])) {
                $form_state['redirect'] = $form_state['form_info']['cancel path'];
            }
        }
    }
}

/**
 * Create a path from the form info and a given step.
 */
function ctools_wizard_get_path($form_info, $step) {
    if (is_array($form_info['path'])) {
        foreach ($form_info['path'] as $id => $part) {
            $form_info['path'][$id] = str_replace('%step', $step, $form_info['path'][$id]);
        }
        $path = $form_info['path'];
    }
    else {
        $path = array(
            str_replace('%step', $step, $form_info['path']),
        );
    }
    // If destination is set, carry it over so it'll take effect when
    // saving. The submit handler will unset destination to avoid drupal_goto
    // redirecting us.
    if (!empty($_GET['destination'])) {
        // Ensure that options is an array.
        if (!isset($path[1]) || !is_array($path[1])) {
            $path[1] = array();
        }
        // Add the destination parameter, if not set already.
        $path[1] += drupal_get_destination();
    }
    return $path;
}

/**
 * Set default parameters and callbacks if none are given.
 * Callbacks follows pattern:
 * $form_info['id']_$hook
 * $form_info['id']_$form_info['forms'][$step_key]_$hook
 */
function ctools_wizard_defaults(&$form_info) {
    $hook = $form_info['id'];
    $defaults = array(
        'show trail' => FALSE,
        'free trail' => FALSE,
        'show back' => FALSE,
        'show cancel' => FALSE,
        'show return' => FALSE,
        'next text' => t('Continue'),
        'back text' => t('Back'),
        'return text' => t('Update and return'),
        'finish text' => t('Finish'),
        'cancel text' => t('Cancel'),
    );
    if (!empty($form_info['free trail'])) {
        $defaults['next text'] = t('Update');
        $defaults['finish text'] = t('Save');
    }
    $form_info = $form_info + $defaults;
    // Set form callbacks if they aren't defined.
    foreach ($form_info['forms'] as $step => $params) {
        if (empty($params['form id'])) {
            $form_callback = $hook . '_' . $step . '_form';
            $form_info['forms'][$step]['form id'] = $form_callback;
        }
    }
    // Set button callbacks.
    $callbacks = array(
        'back callback' => '_back',
        'next callback' => '_next',
        'return callback' => '_return',
        'cancel callback' => '_cancel',
        'finish callback' => '_finish',
    );
    foreach ($callbacks as $key => $callback) {
        // Never overwrite if explicity defined.
        if (empty($form_info[$key])) {
            $wizard_callback = $hook . $callback;
            if (function_exists($wizard_callback)) {
                $form_info[$key] = $wizard_callback;
            }
        }
    }
}