racket-webview/rktwebview_qt/rktwebview_qt.cpp

#include "rktwebview_qt.h"
#include "webviewqt.h"
#include "rktwebview.h"
#include "webviewwindow.h"
#include <QApplication>
#include <QTimer>
#include <QSemaphore>
#include <QJsonDocument>
#include <QJsonObject>

#define COMMAND_QUIT    1
#define COMMAND_CLOSE   2
#define COMMAND_CREATE  3
#define COMMAND_SET_URL 4

class Command
{
public:
    int cmd;
    QVector<QVariant> args;
    QVariant result;
    bool done;
public:
    Command(int _cmd) {
        cmd = _cmd;
        done = false;
    }
};

static QString jsonString(QJsonObject obj)
{
    QJsonDocument doc(obj);
    QString j = QString::fromUtf8(doc.toJson(QJsonDocument::JsonFormat::Compact));
    return j;
}

void Rktwebview_qt::processCommands()
{
    while(!_command_queue.empty()) {
        Command *cmd = _command_queue.dequeue();

        switch(cmd->cmd) {
        case COMMAND_QUIT: {
            _app->quit();
            cmd->done = true;
        }
        break;
        case COMMAND_CREATE: {
            int parent = cmd->args[0].toInt();

            void *f = cmd->args[1].value<void *>();
            void (*js_event_cb)(const char *msg) = reinterpret_cast <void(*)(const char *)>(f);

            QWidget *p;
            if (_views.contains(parent)) {
                p = _views[parent];
            } else {
                p = nullptr;
            }

            WebviewWindow *w = new WebviewWindow(p);
            WebViewQt *view = new WebViewQt(nextHandle(), w);
            w->addView(view, this);

            int id = view->id();

            _views[id] = w;
            _view_js_callbacks[id] = js_event_cb;

            w->show();

            cmd->result = id;
            cmd->done = true;
        }
        break;
        case COMMAND_CLOSE: {
            int wv = cmd->args[0].toInt();
            if (_views.contains(wv)) {
                WebviewWindow *w= _views[wv];
                _views.remove(wv);
                w->close();
                w->deleteLater();
                cmd->result = true;
            } else {
                cmd->result = false;
            }
            cmd->done = true;
        }
        break;
        case COMMAND_SET_URL: {
            int wv = cmd->args[0].toInt();
            QString url = cmd->args[1].toString();
            if (_views.contains(wv)) {
                WebviewWindow *w = _views[wv];
                WebViewQt *v = w->view();
                QUrl u(url);
                v->setUrl(u);
                cmd->result = true;
            } else {
                cmd->result = false;
            }
            cmd->done = true;
        }
        break;
        default: {
            cmd->result = false;
            cmd->done = true;
        }
        break;
        }
    }
}

void Rktwebview_qt::processJsEventQueue()
{

}

void Rktwebview_qt::removeView(int id)
{
    _views.remove(id);
}

int Rktwebview_qt::nextHandle()
{
    int h = ++_current_handle;
    return h;
}

int Rktwebview_qt::rktWebViewCreate(int parent, void (*js_evt_cb)(const char *))
{
    Command c(COMMAND_CREATE);
    c.args.push_back(parent);
    void *function = reinterpret_cast<void *>(js_evt_cb);
    QVariant f(QVariant::fromValue(function));
    c.args.push_back(f);

    _command_queue.enqueue(&c);

    while(!c.done) { doEvents(); }

    int id = c.result.toInt();
    return id;
}

void Rktwebview_qt::rktWebViewClose(int wv)
{
    Command c(COMMAND_CLOSE);
    c.args.push_back(wv);

    _command_queue.enqueue(&c);

    while(!c.done) { doEvents(); }
}

result_t Rktwebview_qt::rktSetUrl(rktwebview_t wv, const char *url)
{
    Command c(COMMAND_SET_URL);
    QString _url(url);
    c.args.push_back(wv);
    c.args.push_back(_url);
    _command_queue.enqueue(&c);

    while(!c.done) { doEvents(); }

    bool r = c.result.toBool();

    return r ? result_t::oke : result_t::set_navigate_failed;
}

void Rktwebview_qt::pageLoaded(rktwebview_t w, bool ok)
{
    // Inject event handling code for the javascript side
    runJs(w, "window.rkt_event_queue = [];\n"
             "window.rkt_send_event = function(obj) { window.rkt_event_queue.push(obj); };\n"
             "window.rkt_get_events = function() { "
             "    let q = window.rkt_event_queue; "
             "    window.rkt_event_queue = [];"
             "    let json_q = JSON.stringify(q);"
             "    return json_q;"
             "};");

    // trigger page loaded.
    QJsonObject obj;
    obj["event"] = "page-loaded";
    obj["oke"] = ok;
    triggerEvent(w, jsonString(obj));
}

void Rktwebview_qt::triggerEvent(rktwebview_t wv, const QString &msg)
{

}

void Rktwebview_qt::rktQuit()
{
    QList<int> keys = _views.keys();
    int i;
    for(i = 0; i < keys.size(); i++) {
        int view_handle = keys[i];
        rktWebViewClose(view_handle);
    }

    Command c(COMMAND_QUIT);
    _command_queue.enqueue(&c);

    while(!c.done) { doEvents(); }
}

void Rktwebview_qt::runJs(rktwebview_t wv, const char *js)
{
    if (_views.contains(wv)) {
        QString _js(js);
        WebViewQt *view = _views[wv]->view();
        view->runJs(_js);
    }
}

void Rktwebview_qt::doEvents()
{
    _app->processEvents();
}

Rktwebview_qt::Rktwebview_qt(Rktwebview_qt **handler) :
    QObject()
{
    _argc = 1;
    _argv[0] = const_cast<char *>("Rktwebview_qt");


    _current_handle = 0;
    _handler = handler;

    _app = new QApplication(_argc, _argv);
    connect(&_process_commands, &QTimer::timeout, this, &Rktwebview_qt::processCommands);
    _process_commands.start(10);

    *_handler = nullptr;
}