MarkdownView: Merge into TextEditor

Make it a bit more compact, too.

Change-Id: I448164371c5a1d6969a292feba17caa2826f58c3
Reviewed-by: Tasuku Suzuki <tasuku.suzuki@signal-slot.co.jp>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/texteditor/markdowneditor.cpp

@@ -0,0 +1,109 @@
+// Copyright (C) 2023 Tasuku Suzuki
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include "markdowneditor.h"
+
+#include "textdocument.h"
+#include "texteditor.h"
+#include "texteditortr.h"
+
+#include <coreplugin/icore.h>
+#include <coreplugin/coreconstants.h>
+#include <coreplugin/coreplugintr.h>
+#include <coreplugin/minisplitter.h>
+
+#include <QHBoxLayout>
+#include <QScrollBar>
+#include <QTextBrowser>
+#include <QToolButton>
+
+namespace TextEditor::Internal {
+
+const char MARKDOWNVIEWER_ID[] = "Editors.MarkdownViewer";
+const char MARKDOWNVIEWER_MIME_TYPE[] = "text/markdown";
+const char MARKDOWNVIEWER_EDITOR_CONTEXT[] = "Editors.MarkdownViewer.Id";
+
+class MarkdownEditor : public Core::IEditor
+{
+public:
+    MarkdownEditor()
+        : m_document(new TextDocument(MARKDOWNVIEWER_ID))
+    {
+        m_document->setMimeType(MARKDOWNVIEWER_MIME_TYPE);
+
+        // Left side
+        auto browser = new QTextBrowser(&m_widget);
+        browser->setOpenExternalLinks(true);
+        browser->setFrameShape(QFrame::NoFrame);
+
+        // Right side (hidable)
+        auto editor = new TextEditorWidget(&m_widget);
+        editor->setTextDocument(m_document);
+        editor->setupGenericHighlighter();
+        editor->setMarksVisible(false);
+
+        auto context = new Core::IContext(this);
+        context->setWidget(editor);
+        context->setContext(Core::Context(MARKDOWNVIEWER_EDITOR_CONTEXT));
+        Core::ICore::addContextObject(context);
+
+        setContext(Core::Context(MARKDOWNVIEWER_ID));
+        setWidget(&m_widget);
+
+        auto toggleEditorVisible = new QToolButton;
+        toggleEditorVisible->setText(Tr::tr("Hide Editor"));
+        toggleEditorVisible->setCheckable(true);
+        toggleEditorVisible->setChecked(true);
+
+        auto layout = new QHBoxLayout(&m_toolbar);
+        layout->setSpacing(0);
+        layout->setContentsMargins(0, 0, 0, 0);
+        layout->addStretch();
+        layout->addWidget(toggleEditorVisible);
+
+        connect(m_document.data(), &TextDocument::mimeTypeChanged,
+                m_document.data(), &TextDocument::changed);
+
+        connect(toggleEditorVisible, &QToolButton::toggled,
+                editor, [editor, toggleEditorVisible](bool editorVisible) {
+            if (editor->isVisible() == editorVisible)
+                return;
+            editor->setVisible(editorVisible);
+            toggleEditorVisible->setText(editorVisible ? Tr::tr("Hide Editor") : Tr::tr("Show Editor"));
+        });
+
+        connect(m_document->document(), &QTextDocument::contentsChanged, this, [this, browser] {
+            QHash<QScrollBar *, int> positions;
+            const auto scrollBars = findChildren<QScrollBar *>();
+
+            // save scroll positions
+            for (QScrollBar *scrollBar : scrollBars)
+                positions.insert(scrollBar, scrollBar->value());
+
+            browser->setMarkdown(m_document->plainText());
+
+            // restore scroll positions
+            for (QScrollBar *scrollBar : scrollBars)
+                scrollBar->setValue(positions.value(scrollBar));
+        });
+    }
+
+    QWidget *toolBar() override { return &m_toolbar; }
+
+    Core::IDocument *document() const override { return m_document.data(); }
+
+private:
+    Core::MiniSplitter m_widget;
+    TextDocumentPtr m_document;
+    QWidget m_toolbar;
+};
+
+MarkdownEditorFactory::MarkdownEditorFactory()
+{
+    setId(MARKDOWNVIEWER_ID);
+    setDisplayName(::Core::Tr::tr("Markdown Viewer"));
+    addMimeType(MARKDOWNVIEWER_MIME_TYPE);
+    setEditorCreator([] { return new MarkdownEditor; });
+}
+
+} // TextEditor::Internal