<?php
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
* Event API                                                                 *
\* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/** @private */
global $_shm_event_listeners;
$_shm_event_listeners = [];

function _load_event_listeners(): void
{
    global $_shm_event_listeners;

    $cache_path = data_path("cache/shm_event_listeners.php");
    if (COMPILE_ELS && file_exists($cache_path)) {
        require_once($cache_path);
    } else {
        _set_event_listeners();

        if (COMPILE_ELS) {
            _dump_event_listeners($_shm_event_listeners, $cache_path);
        }
    }
}

function _set_event_listeners(): void
{
    global $_shm_event_listeners;
    $_shm_event_listeners = [];

    foreach (get_declared_classes() as $class) {
        $rclass = new ReflectionClass($class);
        if ($rclass->isAbstract()) {
            // don't do anything
        } elseif (is_subclass_of($class, "Extension")) {
            /** @var Extension $extension */
            $extension = new $class();

            // skip extensions which don't support our current database
            if (!$extension->is_live()) {
                continue;
            }

            foreach (get_class_methods($extension) as $method) {
                if (substr($method, 0, 2) == "on") {
                    $event = substr($method, 2) . "Event";
                    $pos = $extension->get_priority() * 100;
                    while (isset($_shm_event_listeners[$event][$pos])) {
                        $pos += 1;
                    }
                    $_shm_event_listeners[$event][$pos] = $extension;
                }
            }
        }
    }
}

function _dump_event_listeners(array $event_listeners, string $path): void
{
    $p = "<"."?php\n";

    foreach (get_declared_classes() as $class) {
        $rclass = new ReflectionClass($class);
        if ($rclass->isAbstract()) {
        } elseif (is_subclass_of($class, "Extension")) {
            $p .= "\$$class = new $class(); ";
        }
    }

    $p .= "\$_shm_event_listeners = array(\n";
    foreach ($event_listeners as $event => $listeners) {
        $p .= "\t'$event' => array(\n";
        foreach ($listeners as $id => $listener) {
            $p .= "\t\t$id => \$".get_class($listener).",\n";
        }
        $p .= "\t),\n";
    }
    $p .= ");\n";

    $p .= "?".">";
    file_put_contents($path, $p);
}

function ext_is_live(string $ext_name): bool
{
    if (class_exists($ext_name)) {
        /** @var Extension $ext */
        $ext = new $ext_name();
        return $ext->is_live();
    }
    return false;
}


/** @private */
global $_shm_event_count;
$_shm_event_count = 0;

/**
 * Send an event to all registered Extensions.
 */
function send_event(Event $event): void
{
    global $_shm_event_listeners, $_shm_event_count, $_tracer;
    if (!isset($_shm_event_listeners[get_class($event)])) {
        return;
    }
    $method_name = "on".str_replace("Event", "", get_class($event));

    // send_event() is performance sensitive, and with the number
    // of times context gets called the time starts to add up
    $tracer_enabled = constant('EVENT_TRACE');

    if ($tracer_enabled) $_tracer->begin(get_class($event));
    // SHIT: http://bugs.php.net/bug.php?id=35106
    $my_event_listeners = $_shm_event_listeners[get_class($event)];
    ksort($my_event_listeners);

    foreach ($my_event_listeners as $listener) {
        if ($tracer_enabled) $_tracer->begin(get_class($listener));
        if (method_exists($listener, $method_name)) {
            $listener->$method_name($event);
        }
        if ($tracer_enabled) $_tracer->end();
        if($event->stop_processing===true) {
            break;
        }
    }
    $_shm_event_count++;
    if ($tracer_enabled) $_tracer->end();
}