get ready to load ipfs URLs

There is the issue that ipfs URLs are currently case-sensitive with
base58 hashes, but this has been recognized as a problem:
https://github.com/ipfs/ipfs/issues/337
QUrl also converts addresses to lowercase.  So we can't currently
load base58 hashes into QUrl; consequently switched load(QUrl)
to load(QString) for now.  Maybe it can be reverted when they
switch to base32 hashes.

src/main.cpp

@@ -53,7 +53,7 @@ int main(int argc, char *argv[])
     if (parser.isSet(cssOption))
         w.setBrowserStyle(QUrl::fromLocalFile(parser.value(cssOption)));
     if (parser.positionalArguments().count() > 0)
-        w.load(QUrl::fromLocalFile(parser.positionalArguments().last()));
+        w.load(parser.positionalArguments().last());
     w.show();
 
     return app.exec();

src/mainwindow.cpp

@@ -25,6 +25,8 @@
 #include <QTextCodec>
 #include <QTextEdit>
 
+static const QString ipfsScheme = QStringLiteral("ipfs");
+
 MainWindow::MainWindow(QWidget *parent) :
     QMainWindow(parent),
     ui(new Ui::MainWindow)
@@ -64,25 +66,28 @@ void MainWindow::on_actionOpen_triggered()
                                   << "text/plain");
     if (fileDialog.exec() != QDialog::Accepted)
         return;
-    load(fileDialog.selectedUrls().first());
+    load(fileDialog.selectedFiles().first());
 }
 
-bool MainWindow::load(QUrl url)
+bool MainWindow::load(QString url)
 {
     qDebug() << url;
-    if (url.isRelative()) {
-        QUrl res = url.resolved(m_mainWidget->document()->baseUrl()); // doesn't work for local files
-        qDebug() << url << res << res.fileName() << url.toString();
+    QUrl urlForm = QUrl::fromUserInput(url);
+    if (urlForm.isRelative()) {
+        QUrl res = urlForm.resolved(m_mainWidget->document()->baseUrl()); // doesn't work for local files
+        qDebug() << url << res << res.fileName() << urlForm.toString();
         // correct for QUrl::resolved() being broken
-        if (res.fileName() != url.toString())
-            res = QUrl(res.toString() + QLatin1Char('/') + url.toString());
-        qDebug() << url << res << res.fileName() << url.toString();
-        url = res;
+        if (res.fileName() != urlForm.toString())
+            res = QUrl(res.toString() + QLatin1Char('/') + urlForm.toString());
+        qDebug() << url << res << res.fileName() << urlForm.toString();
+        urlForm = res;
+        ui->urlField->setText(urlForm.toString());
+    } else {
+        ui->urlField->setText(url);
     }
-
     bool success = false;
-    if (url.isLocalFile()) {
-        QString f = url.toLocalFile();
+    if (urlForm.isLocalFile()) {
+        QString f = urlForm.toLocalFile();
         QFile file(f);
         if (QFile::exists(f) && file.open(QFile::ReadOnly)) {
             QByteArray data = file.readAll();
@@ -108,19 +113,26 @@ bool MainWindow::load(QUrl url)
             else
                 success = false;
         }
+    } else if (urlForm.scheme() == ipfsScheme || url.startsWith(QLatin1String("Qm"))) {
+        qDebug() << "ipfs get" << url;
     } else {
-        statusBar()->showMessage(tr("remote loading is not yet implemented: \"%1\"").arg(url.toString()));
+        statusBar()->showMessage(tr("remote loading is not yet implemented: \"%1\"").arg(url));
         return false;
     }
     if (success) {
         m_history.push(url);
-        statusBar()->showMessage(tr("Opened \"%1\"").arg(url.toString()));
+        statusBar()->showMessage(tr("Opened \"%1\"").arg(url));
     } else {
-        statusBar()->showMessage(tr("Could not open \"%1\"").arg(url.toString()));
+        statusBar()->showMessage(tr("Could not open \"%1\"").arg(url));
     }
     return success;
 }
 
+bool MainWindow::loadUrl(QUrl url)
+{
+    return load(url.toString());
+}
+
 bool MainWindow::setBrowserStyle(QUrl url)
 {
     // TODO same url resolution as in load()
@@ -152,3 +164,8 @@ void MainWindow::on_browser_backwardAvailable(bool a)
     Q_UNUSED(a)
 //    ui->actionGo_back->setEnabled(a);
 }
+
+void MainWindow::on_urlField_returnPressed()
+{
+    load(ui->urlField->text());
+}

src/mainwindow.h

@@ -37,7 +37,8 @@ class MainWindow : public QMainWindow
     ~MainWindow();
 
 public slots:
-    bool load(QUrl url);
+    bool load(QString url);
+    bool loadUrl(QUrl url);
     bool setBrowserStyle(QUrl url);
 
 private slots:
@@ -46,10 +47,12 @@ private slots:
     void on_actionGo_back_triggered();
     void on_browser_backwardAvailable(bool a);
 
+    void on_urlField_returnPressed();
+
 private:
     Ui::MainWindow *ui;
     QTextEdit *m_mainWidget;
-    QStack<QUrl> m_history; // correct for QTextBrowser history being broken (only for markdown?)
+    QStack<QString> m_history; // correct for QTextBrowser history being broken (only for markdown?)
 };
 
 #endif // MAINWINDOW_H

src/mainwindow.ui

@@ -121,7 +121,7 @@
    <sender>browser</sender>
    <signal>anchorClicked(QUrl)</signal>
    <receiver>MainWindow</receiver>
-   <slot>load(QUrl)</slot>
+   <slot>loadUrl(QUrl)</slot>
    <hints>
     <hint type="sourcelabel">
      <x>136</x>
@@ -135,6 +135,6 @@
   </connection>
  </connections>
  <slots>
-  <slot>load(QUrl)</slot>
+  <slot>loadUrl(QUrl)</slot>
  </slots>
 </ui>