<?php
/**
 * StatusNet, the distributed open-source microblogging tool
 *
 * Authorize an OAuth request token
 *
 * PHP version 5
 *
 * LICENCE: This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @category  API
 * @package   StatusNet
 * @author    Zach Copley <zach@status.net>
 * @copyright 2010-2011 StatusNet, Inc.
 * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
 * @link      http://status.net/
 */

if (!defined('STATUSNET')) {
    exit(1);
}

/**
 * Authorize an OAuth request token
 *
 * @category API
 * @package  StatusNet
 * @author   Zach Copley <zach@status.net>
 * @license  http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
 * @link     http://status.net/
 */
class ApiOAuthAuthorizeAction extends ApiOAuthAction
{
    var $oauthTokenParam;
    var $reqToken;
    var $callback;
    var $app;
    var $nickname;
    var $password;
    var $store;

    /**
     * Is this a read-only action?
     *
     * @return boolean false
     */
    function isReadOnly($args)
    {
        return false;
    }

    function prepare($args)
    {
        parent::prepare($args);

        $this->nickname        = $this->trimmed('nickname');
        $this->password        = $this->arg('password');
        $this->oauthTokenParam = $this->arg('oauth_token');
        $this->mode            = $this->arg('mode');
        $this->store           = new ApiGNUsocialOAuthDataStore();

        try {
            $this->app = $this->store->getAppByRequestToken($this->oauthTokenParam);
        } catch (Exception $e) {
            $this->clientError($e->getMessage());
        }

        return true;
    }

    /**
     * Handle input, produce output
     *
     * Switches on request method; either shows the form or handles its input.
     *
     * @param array $args $_REQUEST data
     *
     * @return void
     */
    function handle()
    {
        parent::handle();

        if ($_SERVER['REQUEST_METHOD'] == 'POST') {

            $this->handlePost();

        } else {

            // Make sure a oauth_token parameter was provided
            if (empty($this->oauthTokenParam)) {
                // TRANS: Client error given when no oauth_token was passed to the OAuth API.
                $this->clientError(_('No oauth_token parameter provided.'));
            } else {

                // Check to make sure the token exists
                $this->reqToken = $this->store->getTokenByKey($this->oauthTokenParam);

                if (empty($this->reqToken)) {
                    // TRANS: Client error given when an invalid request token was passed to the OAuth API.
                    $this->clientError(_('Invalid request token.'));
                } else {

                    // Check to make sure we haven't already authorized the token
                    if ($this->reqToken->state != 0) {
                        // TRANS: Client error given when an invalid request token was passed to the OAuth API.
                        $this->clientError(_('Request token already authorized.'));
                    }
                }
            }

            // make sure there's an app associated with this token
            if (empty($this->app)) {
                // TRANS: Client error given when an invalid request token was passed to the OAuth API.
                $this->clientError(_('Invalid request token.'));
            }

            $name = $this->app->name;

            $this->showForm();
        }
    }

    function handlePost()
    {
        // check session token for CSRF protection.

        $token = $this->trimmed('token');

        if (!$token || $token != common_session_token()) {
            $this->showForm(
                // TRANS: Form validation error in API OAuth authorisation because of an invalid session token.
                _('There was a problem with your session token. Try again, please.'));
            return;
        }

        // check creds

        $user = null;

        if (!common_logged_in()) {

            // XXX Force credentials check?

            // @fixme this should probably use a unified login form handler
            $user = null;
            if (Event::handle('StartOAuthLoginCheck', array($this, &$user))) {
                $user = common_check_user($this->nickname, $this->password);
            }
            Event::handle('EndOAuthLoginCheck', array($this, &$user));

            if (empty($user)) {
                // TRANS: Form validation error given when an invalid username and/or password was passed to the OAuth API.
                $this->showForm(_("Invalid nickname / password!"));
                return;
            }
        } else {
            $user = common_current_user();
        }

        // fetch the token
        $this->reqToken = $this->store->getTokenByKey($this->oauthTokenParam);
        assert(!empty($this->reqToken));

        if ($this->arg('allow')) {
            // mark the req token as authorized
            try {
                $this->store->authorize_token($this->oauthTokenParam);
            } catch (Exception $e) {
                $this->serverError($e->getMessage());
            }

            common_log(
                LOG_INFO,
                sprintf(
                    "API OAuth - User %d (%s) has authorized request token %s for OAuth application %d (%s).",
                    $user->id,
                    $user->nickname,
                    $this->reqToken->tok,
                    $this->app->id,
                    $this->app->name
                )
            );

            $tokenAssoc = new Oauth_token_association();

            $tokenAssoc->profile_id     = $user->id;
            $tokenAssoc->application_id = $this->app->id;
            $tokenAssoc->token          = $this->oauthTokenParam;
            $tokenAssoc->created        = common_sql_now();

            $result = $tokenAssoc->insert();

            if (!$result) {
                common_log_db_error($tokenAssoc, 'INSERT', __FILE__);
                // TRANS: Server error displayed when a database action fails.
                $this->serverError(_('Database error inserting oauth_token_association.'));
            }

            $callback = $this->getCallback();

            if (!empty($callback) && $this->reqToken->verified_callback != 'oob') {
                $targetUrl = $this->buildCallbackUrl(
                    $callback,
                    array(
                        'oauth_token'    => $this->oauthTokenParam,
                        'oauth_verifier' => $this->reqToken->verifier // 1.0a
                    )
                );

                common_log(LOG_INFO, "Redirecting to callback: $targetUrl");

                // Redirect the user to the provided OAuth callback
                common_redirect($targetUrl, 303);

            } elseif ($this->app->type == 2) {
                // Strangely, a web application seems to want to do the OOB
                // workflow. Because no callback was specified anywhere.
                common_log(
                    LOG_WARNING,
                    sprintf(
                        "API OAuth - No callback provided for OAuth web client ID %s (%s) "
                         . "during authorization step. Falling back to OOB workflow.",
                        $this->app->id,
                        $this->app->name
                    )
                );
            }

            // Otherwise, inform the user that the rt was authorized
            $this->showAuthorized();
        } else if ($this->arg('cancel')) {
            common_log(
                LOG_INFO,
                sprintf(
                    "API OAuth - User %d (%s) refused to authorize request token %s for OAuth application %d (%s).",
                    $user->id,
                    $user->nickname,
                    $this->reqToken->tok,
                    $this->app->id,
                    $this->app->name
                )
            );

            try {
                $this->store->revoke_token($this->oauthTokenParam, 0);
            } catch (Exception $e) {
                $this->ServerError($e->getMessage());
            }

            $callback = $this->getCallback();

            // If there's a callback available, inform the consumer the user
            // has refused authorization
            if (!empty($callback) && $this->reqToken->verified_callback != 'oob') {
                $targetUrl = $this->buildCallbackUrl(
                    $callback,
                    array(
                        'oauth_problem' => 'user_refused',
                    )
                );

                common_log(LOG_INFO, "Redirecting to callback: $targetUrl");

                // Redirect the user to the provided OAuth callback
                common_redirect($targetUrl, 303);
            }

            // otherwise inform the user that authorization for the rt was declined
            $this->showCanceled();

        } else {
            // TRANS: Client error given on when invalid data was passed through a form in the OAuth API.
            $this->clientError(_('Unexpected form submission.'));
        }
    }

    /**
     * Show body - override to add a special CSS class for the authorize
     * page's "desktop mode" (minimal display)
     *
     * Calls template methods
     *
     * @return nothing
     */
    function showBody()
    {
        $bodyClasses = array();

        if ($this->desktopMode()) {
            $bodyClasses[] = 'oauth-desktop-mode';
        }

        if (common_current_user()) {
            $bodyClasses[] = 'user_in';
        }

        $attrs = array('id' => strtolower($this->trimmed('action')));

        if (!empty($bodyClasses)) {
            $attrs['class'] = implode(' ', $bodyClasses);
        }

        $this->elementStart('body', $attrs);

        $this->elementStart('div', array('id' => 'wrap'));
        if (Event::handle('StartShowHeader', array($this))) {
            $this->showHeader();
            Event::handle('EndShowHeader', array($this));
        }
        $this->showCore();
        if (Event::handle('StartShowFooter', array($this))) {
            $this->showFooter();
            Event::handle('EndShowFooter', array($this));
        }
        $this->elementEnd('div');
        $this->showScripts();
        $this->elementEnd('body');
    }

    function showForm($error=null)
    {
        $this->error = $error;
        $this->showPage();
    }

    function showScripts()
    {
        parent::showScripts();
        if (!common_logged_in()) {
            $this->autofocus('nickname');
        }
    }

    /**
     * Title of the page
     *
     * @return string title of the page
     */
    function title()
    {
        // TRANS: Title for a page where a user can confirm/deny account access by an external application.
        return _('An application would like to connect to your account');
    }

    /**
     * Shows the authorization form.
     *
     * @return void
     */
    function showContent()
    {
        $this->elementStart('form', array('method' => 'post',
                                          'id' => 'form_apioauthauthorize',
                                          'class' => 'form_settings',
                                          'action' => common_local_url('ApiOAuthAuthorize')));
        $this->elementStart('fieldset');
        $this->element('legend', array('id' => 'apioauthauthorize_allowdeny'),
                                 // TRANS: Fieldset legend.
                                 _('Allow or deny access'));

        $this->hidden('token', common_session_token());
	$this->hidden('mode', $this->mode);
        $this->hidden('oauth_token', $this->oauthTokenParam);
        $this->hidden('oauth_callback', $this->callback);

        $this->elementStart('ul', 'form_data');
        $this->elementStart('li');
        $this->elementStart('p');
        if (!empty($this->app->icon) && $this->app->name != 'anonymous') {
            $this->element('img', array('src' => $this->app->icon));
        }

        $access = ($this->app->access_type & Oauth_application::$writeAccess) ?
          'access and update' : 'access';

        if ($this->app->name == 'anonymous') {
            // Special message for the anonymous app and consumer.
            // TRANS: User notification of external application requesting account access.
            // TRANS: %3$s is the access type requested (read-write or read-only), %4$s is the StatusNet sitename.
            $msg = _('An application would like the ability ' .
                 'to <strong>%3$s</strong> your %4$s account data. ' .
                 'You should only give access to your %4$s account ' .
                 'to third parties you trust.');
        } else {
            // TRANS: User notification of external application requesting account access.
            // TRANS: %1$s is the application name requesting access, %2$s is the organisation behind the application,
            // TRANS: %3$s is the access type requested, %4$s is the StatusNet sitename.
            $msg = _('The application <strong>%1$s</strong> by ' .
                     '<strong>%2$s</strong> would like the ability ' .
                     'to <strong>%3$s</strong> your %4$s account data. ' .
                     'You should only give access to your %4$s account ' .
                     'to third parties you trust.');
        }

        $this->raw(sprintf($msg,
                           $this->app->name,
                           $this->app->organization,
                           $access,
                           common_config('site', 'name')));
        $this->elementEnd('p');
        $this->elementEnd('li');
        $this->elementEnd('ul');

        // quickie hack
        $button = false;
        if (!common_logged_in()) {
            if (Event::handle('StartOAuthLoginForm', array($this, &$button))) {
                $this->elementStart('fieldset');
                // TRANS: Fieldset legend.
                $this->element('legend', null, _m('LEGEND','Account'));
                $this->elementStart('ul', 'form_data');
                $this->elementStart('li');
                // TRANS: Field label on OAuth API authorisation form.
                $this->input('nickname', _('Nickname'));
                $this->elementEnd('li');
                $this->elementStart('li');
                // TRANS: Field label on OAuth API authorisation form.
                $this->password('password', _('Password'));
                $this->elementEnd('li');
                $this->elementEnd('ul');

                $this->elementEnd('fieldset');
            }
            Event::handle('EndOAuthLoginForm', array($this, &$button));
        }

        $this->element('input', array('id' => 'cancel_submit',
                                      'class' => 'submit submit form_action-primary',
                                      'name' => 'cancel',
                                      'type' => 'submit',
                                      // TRANS: Button text that when clicked will cancel the process of allowing access to an account
                                      // TRANS: by an external application.
                                      'value' => _m('BUTTON','Cancel')));

        $this->element('input', array('id' => 'allow_submit',
                                      'class' => 'submit submit form_action-secondary',
                                      'name' => 'allow',
                                      'type' => 'submit',
                                      // TRANS: Button text that when clicked will allow access to an account by an external application.
                                      'value' => $button ? $button : _m('BUTTON','Allow')));

        $this->elementEnd('fieldset');
        $this->elementEnd('form');
    }

    /**
     * Instructions for using the form
     *
     * For "remembered" logins, we make the user re-login when they
     * try to change settings. Different instructions for this case.
     *
     * @return void
     */
    function getInstructions()
    {
        // TRANS: Form instructions.
        return _('Authorize access to your account information.');
    }

    /**
     * A local menu
     *
     * Shows different login/register actions.
     *
     * @return void
     */
    function showLocalNav()
    {
        // NOP
    }

    /*
     * Checks to see if a the "mode" parameter is present in the request
     * and set to "desktop". If it is, the page is meant to be displayed in
     * a small frame of another application, and we should  suppress the
     * header, aside, and footer.
     */
    function desktopMode()
    {
        if (isset($this->mode) && $this->mode == 'desktop') {
            return true;
        } else {
            return false;
        }
    }

    /*
     * Override - suppress output in "desktop" mode
     */
    function showHeader()
    {
        if ($this->desktopMode() == false) {
            parent::showHeader();
        }
    }

    /*
     * Override - suppress output in "desktop" mode
     */
    function showAside()
    {
        if ($this->desktopMode() == false) {
            parent::showAside();
        }
    }

    /*
     * Override - suppress output in "desktop" mode
     */
    function showFooter()
    {
        if ($this->desktopMode() == false) {
            parent::showFooter();
        }
    }

    /**
     * Show site notice.
     *
     * @return nothing
     */
    function showSiteNotice()
    {
        // NOP
    }

    /**
     * Show notice form.
     *
     * Show the form for posting a new notice
     *
     * @return nothing
     */
    function showNoticeForm()
    {
        // NOP
    }

    /*
     * Show a nice message confirming the authorization
     * operation was canceled.
     *
     * @return nothing
     */
    function showCanceled()
    {
        $info = new InfoAction(
            // TRANS: Header for user notification after revoking OAuth access to an application.
            _('Authorization canceled.'),
            sprintf(
                // TRANS: User notification after revoking OAuth access to an application.
                // TRANS: %s is an OAuth token.
                _('The request token %s has been revoked.'),
                $this->oauthTokenParam
            )
        );

        $info->showPage();
    }

    /*
     * Show a nice message that the authorization was successful.
     * If the operation is out-of-band, show a pin.
     *
     * @return nothing
     */
    function showAuthorized()
    {
        $title = null;
        $msg   = null;

        if ($this->app->name == 'anonymous') {

            $title =
                // TRANS: Title of the page notifying the user that an anonymous client application was successfully authorized to access the user's account with OAuth.
                _('You have successfully authorized the application');

            $msg =
                // TRANS: Message notifying the user that an anonymous client application was successfully authorized to access the user's account with OAuth.
                _('Please return to the application and enter the following security code to complete the process.');

        } else {

            $title = sprintf(
                // TRANS: Title of the page notifying the user that the client application was successfully authorized to access the user's account with OAuth.
                // TRANS: %s is the authorised application name.
                _('You have successfully authorized %s'),
                $this->app->name
            );

            $msg = sprintf(
                // TRANS: Message notifying the user that the client application was successfully authorized to access the user's account with OAuth.
                // TRANS: %s is the authorised application name.
                _('Please return to %s and enter the following security code to complete the process.'),
                $this->app->name
            );

        }

        if ($this->reqToken->verified_callback == 'oob') {
            $pin = new ApiOAuthPinAction(
                $title,
                $msg,
                $this->reqToken->verifier,
                $this->desktopMode()
            );
            $pin->showPage();
        } else {
            // NOTE: This would only happen if an application registered as
            // a web application but sent in 'oob' for the oauth_callback
            // parameter. Usually web apps will send in a callback and
            // not use the pin-based workflow.

            $info = new InfoAction(
                $title,
                $msg,
                $this->oauthTokenParam,
                $this->reqToken->verifier
            );

            $info->showPage();
        }
    }

    /*
     * Figure out what the callback should be
     */
    function getCallback()
    {
        $callback = null;

        // Return the verified callback if we have one
        if ($this->reqToken->verified_callback != 'oob') {

            $callback = $this->reqToken->verified_callback;

            // Otherwise return the callback that was provided when
            // registering the app
            if (empty($callback)) {

                common_debug(
                    "No verified callback found for request token, using application callback: "
                        . $this->app->callback_url,
                     __FILE__
                );

                $callback = $this->app->callback_url;
            }
        }

        return $callback;
    }

    /*
     * Properly format the callback URL and parameters so it's
     * suitable for a redirect in the OAuth dance
     *
     * @param string $url       the URL
     * @param array  $params    an array of parameters
     *
     * @return string $url  a URL to use for redirecting to
     */
    function buildCallbackUrl($url, $params)
    {
        foreach ($params as $k => $v) {
            $url = $this->appendQueryVar(
                $url,
                OAuthUtil::urlencode_rfc3986($k),
                OAuthUtil::urlencode_rfc3986($v)
            );
        }

        return $url;
    }

    /*
     * Append a new query parameter after any existing query
     * parameters.
     *
     * @param string $url   the URL
     * @prarm string $k     the parameter name
     * @param string $v     value of the paramter
     *
     * @return string $url  the new URL with added parameter
     */
    function appendQueryVar($url, $k, $v) {
        $url = preg_replace('/(.*)(\?|&)' . $k . '=[^&]+?(&)(.*)/i', '$1$2$4', $url . '&');
        $url = substr($url, 0, -1);
        if (strpos($url, '?') === false) {
            return ($url . '?' . $k . '=' . $v);
        } else {
            return ($url . '&' . $k . '=' . $v);
        }
    }
}