<?php

/**
 * @file class.CloserPlugin.php :: Requires PHP5.6+
 *
 * @author Grizly <clonemeagain@gmail.com>
 * @see https://github.com/clonemeagain/plugin-autocloser
 */
foreach ([
 'canned',
 'format',
 'list',
 'orm',
 'misc',
 'plugin',
 'ticket',
 'signal',
 'staff'
] as $c) {
    require_once INCLUDE_DIR . "class.$c.php";
}
require_once 'config.php';

/**
 * The goal of this Plugin is to close tickets when they get old. Logans Run
 * style.
 */
class CloserPlugin extends Plugin {

    var $config_class = 'CloserPluginConfig';

    /**
     * Set to TRUE to enable extra logging.
     *
     * @var boolean
     */
    const DEBUG = FALSE;

    /**
     * The name that appears in threads as: Closer Plugin.
     *
     * @var string
     */
    const PLUGIN_NAME = 'Closer Plugin';

    /**
     * Hook the bootstrap process Run on every instantiation, so needs to be
     * concise.
     *
     * {@inheritdoc}
     *
     * @see Plugin::bootstrap()
     */
    public function bootstrap() {
        // Listen for cron Signal, which only happens at end of class.cron.php:
        Signal::connect('cron', function ($ignored, $data) {

            // Autocron is an admin option, we can filter out Autocron Signals
            // to ensure changing state for potentially hundreds/thousands
            // of tickets doesn't affect interactive Agent/User experience.
            $use_autocron = $this->getConfig()->get('use_autocron');

            // Autocron Cron Signals are sent with this array key set to TRUE
            $is_autocron = (isset($data['autocron']) && $data['autocron']);

            // Normal cron isn't Autocron:
            if (!$is_autocron || ($use_autocron && $is_autocron))
                $this->logans_run_mode();
        });
    }

    /**
     * Closes old tickets.. with extreme prejudice.. or, regular prejudice..
     * whatever. = Welcome to the 23rd Century. The perfect world of total
     * pleasure. ... there's just one catch.
     */
    private function logans_run_mode() {
// Anpassung Anfang: für die v1.17
        // Ab der v1.17 gibt es Plugin-Instanzen
        // erste aktive Instanz ermitteln und diese Config laden
        if(method_exists($this, 'getActiveInstances')) {
            $instance = $this->getActiveInstances()->first();
            $config = $this->getConfig($instance);
        } else
// Anpassung Ende: für die v1.17
        $config = $this->getConfig();
        if ($this->is_time_to_run($config)) {
            // Use the number of config groups to run the closer as many times as is needed.
            foreach (range(1, CloserPluginConfig::NUMBER_OF_SETTINGS) as $group_id) {
                if (!$config->get('group-enabled-' . $group_id)) {
                    continue;
                }

                try {
                    $open_ticket_ids = $this->find_ticket_ids($config, $group_id);
                    if (self::DEBUG) {
                        error_log(
                                "CloserPlugin group [$group_id] $group_name has " .
                                count($open_ticket_ids) . " open tickets.");
                    }

                    // Bail if there is no work to do
                    if (!count($open_ticket_ids)) {
                        continue;
                    }

                    // Find the new TicketStatus from the Setting Group config:
                    $new_status = TicketStatus::lookup(
                                    array(
                                        'id' => (int) $config->get('to-status-' . $group_id)
                    ));

                    // Admin note is just text
                    $admin_note = $config->get('admin-note-' . $group_id) ?: FALSE;

                    // Fetch the actual content of the reply, "html" means load with images, 
                    // I don't think it works with attachments though.
                    $admin_reply = $config->get('admin-reply-' . $group_id);
                    if (is_numeric($admin_reply) && $admin_reply) {
                        // We have a valid Canned_Response ID, fetch the actual Canned:
                        $admin_reply = Canned::lookup($admin_reply);
                        if ($admin_reply instanceof Canned) {
                            // Got a real Canned object, let's pull the body/string:
                            $admin_reply = $admin_reply->getFormattedResponse('html');
                        }
                    }

                    if (self::DEBUG) {
                        print
                                "Found the following details:\nAdmin Note: $admin_note\n\nAdmin Reply: $admin_reply\n";
                    }

                    // Get the robot for this group
                    $robot = $this->getConfig()->get('robot-account-' . $group_id);
                    $robot = ($robot>0)? $robot = Staff::lookup($robot) : null;

                    // Go through each ticket ID:
                    foreach ($open_ticket_ids as $ticket_id) {

                        // Fetch ticket as an Object
                        $ticket = Ticket::lookup($ticket_id);
                        if (!$ticket instanceof Ticket) {
                            error_log("Ticket $ticket_id was not instatiable. :-(");
                            continue;
                        }

                        // Some tickets aren't closeable.. either because of open tasks, or missing fields.
                        // we can therefore only work on closeable tickets.
                        // This won't close it, nor will it send a response, so it will likely trigger again
                        // on the next run.. TRUE means send an alert.
                        if (!$ticket->isCloseable()) {
                            $ticket->LogNote(__('Error auto-changing status'), __(
                                            'Unable to change this ticket\'s status to ' .
                                            $new_status->getState()), self::PLUGIN_NAME, TRUE);
                            continue;
                        }

                        // Add a Note to the thread indicating it was closed by us, don't send an alert.
                        if ($admin_note) {
                            $ticket->LogNote(
                                    __('Changing status to: ' . $new_status->getState()), $admin_note, self::PLUGIN_NAME, FALSE);
                        }

                        // Post a Reply to the user, telling them the ticket is closed, relates to issue #2
                        if ($admin_reply) {
                            $this->post_reply($ticket, $new_status, $admin_reply, $robot);
                        }

                        // Actually change the ticket status
                        $this->change_ticket_status($ticket, $new_status);
                    }
                } catch (Exception $e) {
                    // Well, something borked
                    error_log(
                            "Exception encountered, we'll soldier on, but something is broken!");
                    error_log($e->getMessage());
                    if (self::DEBUG)
                        print_r($e->getTrace());
                }
            }
        }
    }

    /**
     * Calculates when it's time to run the plugin, based on the config. Uses
     * things like: How long the admin defined the cycle to be? When it was last
     * run
     *
     * @param PluginConfig $config
     * @return boolean
     */
    private function is_time_to_run(PluginConfig $config) {
        // We can store arbitrary things in the config, like, when we ran this last:
        $last_run = $config->get('last-run');
        $now = Misc::dbtime(); // Never assume about time..
        $config->set('last-run', $now);

        // assume a freqency of "Every Cron" means it is always overdue
        $next_run = 0;

        // Convert purge frequency to a comparable format to timestamps:
        if ($freq_in_config = (int) $config->get('purge-frequency')) {
            // Calculate when we want to run next, config hours into seconds,
            // plus the last run is the timestamp of the next scheduled run
            $next_run = $last_run + ($freq_in_config * 3600);
        }

        // See if it's time to check old tickets
        // Always run when in DEBUG mode.. because waiting for the scheduler is slow
        // If we don't have a next_run, it's because we want it to run
        // If the next run is in the past, then we are overdue, so, lets go!
        if (self::DEBUG || !$next_run || $now > $next_run) {
            return TRUE;
        }
        return FALSE;
    }

    /**
     * This is the part that actually "Closes" the tickets Well, depending on the
     * admin settings I mean. Could use $ticket->setStatus($closed_status)
     * function however, this gives us control over _how_ it is closed. preventing
     * accidentally making any logged-in staff associated with the closure, which
     * is an issue with AutoCron
     *
     * @param Ticket $ticket
     * @param TicketStatus $new_status
     */
    private function change_ticket_status(Ticket $ticket, TicketStatus $new_status) {
        if (self::DEBUG) {
            error_log(
                    "Setting status " . $new_status->getState() .
                    " for ticket {$ticket->getId()}::{$ticket->getSubject()}");
        }

        // Start by setting the last update and closed timestamps to now
        $ticket->closed = $ticket->lastupdate = SqlFunction::NOW();

        // Remove any duedate or overdue flags
        $ticket->duedate = null;
        $ticket->clearOverdue(FALSE); // flag prevents saving, we'll do that
        // Post an Event with the current timestamp.
        $ticket->logEvent($new_status->getState(), [
            'status' => [
                $new_status->getId(),
                $new_status->getName()
            ]
        ]);
        // Actually apply the new "TicketStatus" to the Ticket.
        $ticket->status = $new_status;

        // Save it, flag prevents it refetching the ticket data straight away (inefficient)
        $ticket->save(FALSE);
    }

    /**
     * Retrieves an array of ticket_id's from the database
     *
     * @param PluginConfig $config
     * @param int $group_id
     * @return array of integers that are Ticket::lookup compatible ID's of Open
     *         Tickets
     * @throws Exception so you have something interesting to read in your cron
     *         logs..
     */
    private function find_ticket_ids(PluginConfig $config, $group_id) {
        $from_status = (int) $config->get('from-status-' . $group_id);
        if (!$from_status) {
            throw new \Exception("Invalid parameter (int) from_status needs to be > 0");
        }

        $age_days = (int) $config->get('purge-age-' . $group_id);
        if ($age_days < 1) {
            throw new \Exception("Invalid parameter (int) age_days needs to be > 0");
        }

        $max = (int) $config->get('purge-num');
        if ($max < 1) {
            throw new \Exception("Invalid parameter (int) max needs to be > 0");
        }

        $whereFilter = ($config->get('close-only-answered-' . $group_id)) ? ' AND isanswered=1' : '';
        $whereFilter .= ($config->get('close-only-overdue-' . $group_id)) ? ' AND isoverdue=1' : '';

        // Ticket query, note MySQL is doing all the date maths:
        // Sidebar: Why haven't we moved to PDO yet?
        /*
         * Attempt to do this with ORM $tickets = Ticket::objects()->filter( array(
         * 'lastupdate' => SqlFunction::DATEDIFF(SqlFunction::NOW(),
         * SqlInterval($age_days, 'DAY')), 'status_id' => $from_status, 'isanswered'
         * => 1, 'isoverdue' => 1 ))->all(); print_r($tickets);
         */

        $sql = sprintf(
                "
SELECT ticket_id 
FROM %s WHERE lastupdate < DATE_SUB(NOW(), INTERVAL %d DAY)
AND status_id=%d %s
ORDER BY ticket_id ASC
LIMIT %d", TICKET_TABLE, $age_days, $from_status, $whereFilter, $max);

        if (self::DEBUG) {
            error_log("Looking for tickets with query: $sql");
        }

        $r = db_query($sql);
        // Fill an array with just the ID's of the tickets:
        $ids = array();
        while ($i = db_fetch_array($r, MYSQLI_ASSOC)) {
            $ids[] = $i['ticket_id'];
        }

        return $ids;
    }

    /**
     * Sends a reply to the ticket creator Wrapper/customizer around the
     * Ticket::postReply method.
     *
     * @param Ticket $ticket
     * @param TicketStatus $new_status
     * @param string $admin_reply
     */
    function post_reply(Ticket $ticket, TicketStatus $new_status, $admin_reply, Staff $robot = null) {
        // We need to override this for the notifications
        global $thisstaff;

        if ($robot) {
            $assignee = $robot;
        } else {
            $assignee = $ticket->getAssignee();
            if (!$assignee instanceof Staff) {
                // Nobody, or a Team was assigned, and we haven't been told to use a Robot account.
                $ticket->logNote(__('AutoCloser Error'), __(
                                'Unable to send reply, no assigned Agent on ticket, and no Robot account specified in config.'), self::PLUGIN_NAME, FALSE);
                return;
            }
        }
        // This actually bypasses any authentication/validation checks..
        $thisstaff = $assignee;

        // Replace any ticket variables in the message:
        $variables = [
            'recipient' => $ticket->getOwner()
        ];

        // Provide extra variables.. because. :-)
        $options = [
            'wholethread' => 'fetch_whole_thread',
            'firstresponse' => 'fetch_first_response',
            'lastresponse' => 'fetch_last_response'
        ];

        // See if they've been used, if so, call the function
        foreach ($options as $option => $method) {
            if (strpos($admin_reply, $option) !== FALSE) {
                $variables[$option] = $this->{$method}($ticket);
            }
        }

        // Use the Ticket objects own replaceVars method, which replace
        // any other Ticket variables.
        $custom_reply = $ticket->replaceVars($admin_reply, $variables);

        // Build an array of values to send to the ticket's postReply function
        // 'emailcollab' => FALSE // don't send notification to all collaborators.. maybe.. dunno.
        $vars = [
            'response' => $custom_reply,
            'reply-to' => 'user'
        ];
        $errors = [];

        // Send the alert without claiming the ticket on our assignee's behalf.
        if (!$sent = $ticket->postReply($vars, $errors, TRUE, FALSE)) {
            $ticket->LogNote(__('Error Notification'), __('We were unable to post a reply to the ticket creator.'), self::PLUGIN_NAME, FALSE);
        }
    }

    /**
     * Fetches the first response sent to the ticket Owner
     *
     * @param Ticket $ticket
     * @return string
     */
    private function fetch_first_response(Ticket $ticket) {
        // Apparently the ORM is fighting me.. it doesn't like me
        $thread = $ticket->getThread();
        if (!$thread instanceof Thread) {
            return '';
        }
        foreach ($thread->getEntries()->all() as $entry) {
            if ($this->is_valid_thread_entry($entry, FALSE, TRUE)) {
                // this is actually a Response. yes..
                return $this->render_thread_entry($entry);
            }
        }
        return ''; // the empty string overwrites the template
    }

    /**
     * Fetches the last response sent to the ticket Owner.
     *
     * @param Ticket $ticket
     * @return string
     */
    private function fetch_last_response(Ticket $ticket) {
        $thread = $ticket->getThread();
        if (!$thread instanceof Thread) {
            return '';
        }

        $last = '';
        // Can't seem to get this sorted in reverse.. thought I had it, but nope.
        foreach ($thread->getEntries()->all() as $entry) {
            if ($this->is_valid_thread_entry($entry, FALSE, TRUE)) {
                // We'll just render each response, overwriting the previous one..
                // screw it. 
                $last = $this->render_thread_entry($entry);
            }
        }
        return $last; // the empty string overwrites the template
    }

    /**
     * Fetches the whole thread that the client can see. As an HTML message.
     *
     * @param Ticket $ticket
     * @return string
     */
    private function fetch_whole_thread(Ticket $ticket) {
        $msg = '';
        $thread = $ticket->getThread();
        if (!$thread instanceof Thread) {
            return $msg;
        }

        // Iterate through all the thread entries (in order), 
        // Not sure the ->order_by() thing even does anything.
        foreach ($thread->getEntries()
                ->order_by('created', QuerySet::ASC)
                ->all() as $entry) {
            // Test each entries data-model, and the type of entry from it's model
            if ($this->is_valid_thread_entry($entry, TRUE, TRUE)) {
                // this is actually a Response or Message yes..
                $msg .= $this->render_thread_entry($entry);
            }
        }
        return $msg;
    }

    /**
     * Renders a ThreadEntry as HTML.
     *
     * @param AnnotatedModel $entry
     * @return string
     */
    private function render_thread_entry(AnnotatedModel $entry) {
        $from = ($entry->get('type') == 'R') ? 'Sent' : 'Received';
        $tag = ($entry->get('format') == 'text') ? 'pre' : 'p';
        $when = Format::datetime(strtotime($entry->get('created')));
        // TODO: Maybe make this a CannedResponse or admin template? 
        return <<<PIECE
<hr />
<p class="thread">
  <h3>{$entry->get('title')}</h3>
  <p>$from Date: $when</p>
  <$tag>{$entry->get('body')}</$tag>
</p>
PIECE;
    }

    /**
     * $entry should be an AnnotatedModel object, however, we need to check that
     * it's actually a type of ThreadEntry, therefore we need to interrogate the
     * Object inside it. Would be good if the $ticket->getResponses() method
     * worked..
     *
     * @param AnnotatedModel $entry
     * @param bool $message
     * @param bool $response
     * @return boolean
     */
    private function is_valid_thread_entry(AnnotatedModel $entry, $message = FALSE, $response = FALSE) {
        if (!$entry->model instanceof ThreadEntry) {
            return FALSE;
        }
        if (!$message && !$response) {
            // you gotta pick one ..
            return FALSE;
        }
        if (self::DEBUG) {
            printf("Testing thread entry: %s : %s\n", $entry->get('type'), $entry->get('title'));
        }
        if (isset($entry->model->ht['type'])) {
            if ($response && $entry->get('type') == 'R') {
                // this is actually a Response
                return TRUE;
            } elseif ($message && $entry->get('type') == 'M') {
                // this is actually a Message
                return TRUE;
            }
        }
        return FALSE;
    }

    /**
     * Required stub.
     *
     * {@inheritdoc}
     *
     * @see Plugin::uninstall()
     */
    function uninstall(&$errors) {
        #$errors = array();
        global $ost;
        // Send an alert to the system admin:
        $ost->alertAdmin(self::PLUGIN_NAME . ' has been uninstalled', "You wanted that right?", true);

        parent::uninstall($errors);
    }

    /**
     * Plugins seem to want this.
     */
    public function getForm() {
        return array();
    }

}