TextEditor: add json indenter

Use an EditorFactory that sets up a custom indenter for json files.

Change-Id: Id5ade9f9f551835131a62e381a972f0b6032e7c0
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/texteditor/CMakeLists.txt

@@ -68,6 +68,7 @@ add_qtc_plugin(TextEditor
     icodestylepreferencesfactory.cpp icodestylepreferencesfactory.h
     indenter.h
     ioutlinewidget.h
+    jsoneditor.cpp jsoneditor.h
     linenumberfilter.cpp linenumberfilter.h
     marginsettings.cpp marginsettings.h
     markdowneditor.cpp markdowneditor.h

src/plugins/texteditor/jsoneditor.cpp

@@ -0,0 +1,95 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include "jsoneditor.h"
+
+#include "autocompleter.h"
+#include "textdocument.h"
+#include "texteditoractionhandler.h"
+#include "texteditortr.h"
+#include "textindenter.h"
+
+namespace TextEditor::Internal {
+
+const char JSON_EDITOR_ID[] = "Editors.Json";
+const char JSON_MIME_TYPE[] = "application/json";
+
+static int startsWith(const QString &line, const QString &closingChars)
+{
+    int count = 0;
+    for (const QChar &lineChar : line) {
+        if (closingChars.contains(lineChar))
+            ++count;
+        else if (!lineChar.isSpace())
+            break;
+    }
+    return count;
+}
+
+class JsonAutoCompleter : public AutoCompleter
+{
+    bool contextAllowsElectricCharacters(const QTextCursor &cursor) const override { return true; }
+};
+
+class JsonIndenter : public TextIndenter
+{
+public:
+    JsonIndenter(QTextDocument *doc) : TextIndenter(doc) {}
+
+    bool isElectricCharacter(const QChar &c) const override
+    {
+        static QString echars("{}[]");
+        return echars.contains(c);
+    }
+
+    int indentFor(const QTextBlock &block,
+                  const TabSettings &tabSettings,
+                  int /*cursorPositionInEditor*/) override
+    {
+        QTextBlock previous = block.previous();
+        if (!previous.isValid())
+            return 0;
+
+        QString previousText = previous.text();
+        while (previousText.trimmed().isEmpty()) {
+            previous = previous.previous();
+            if (!previous.isValid())
+                return 0;
+            previousText = previous.text();
+        }
+
+        int indent = tabSettings.indentationColumn(previousText);
+
+        int adjust = previousText.count('{') + previousText.count('[');
+        adjust -= previousText.count('}') + previousText.count(']');
+        adjust += startsWith(previousText, "}]") - startsWith(block.text(), "}]");
+        adjust *= tabSettings.m_indentSize;
+
+        return qMax(0, indent + adjust);
+    }
+
+    void indentBlock(const QTextBlock &block,
+                     const QChar &typedChar,
+                     const TabSettings &tabSettings,
+                     int cursorPositionInEditor) override
+    {
+        tabSettings.indentLine(block, indentFor(block, tabSettings, cursorPositionInEditor));
+    }
+};
+
+JsonEditorFactory::JsonEditorFactory()
+{
+    setId(JSON_EDITOR_ID);
+    setDisplayName(Tr::tr("Json Editor"));
+    addMimeType(JSON_MIME_TYPE);
+
+    setEditorCreator([] { return new BaseTextEditor; });
+    setEditorWidgetCreator([] { return new TextEditorWidget; });
+    setDocumentCreator([] { return new TextDocument(JSON_EDITOR_ID); });
+    setAutoCompleterCreator([] { return new JsonAutoCompleter; });
+    setIndenterCreator([](QTextDocument *doc) { return new JsonIndenter(doc); });
+    setEditorActionHandlers(TextEditorActionHandler::Format);
+    setUseGenericHighlighter(true);
+}
+
+} // namespace TextEditor::Internal

src/plugins/texteditor/jsoneditor.h

@@ -0,0 +1,16 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#pragma once
+
+#include "texteditor.h"
+
+namespace TextEditor::Internal {
+
+class JsonEditorFactory final : public TextEditorFactory
+{
+public:
+    JsonEditorFactory();
+};
+
+} // TextEditor::Internal

src/plugins/texteditor/texteditor.qbs

@@ -90,6 +90,8 @@ Project {
             "icodestylepreferencesfactory.h",
             "indenter.h",
             "ioutlinewidget.h",
+            "jsoneditor.cpp",
+            "jsoneditor.h",
             "linenumberfilter.cpp",
             "linenumberfilter.h",
             "marginsettings.cpp",

src/plugins/texteditor/texteditorplugin.cpp

@@ -10,6 +10,7 @@
 #include "fontsettings.h"
 #include "highlighter.h"
 #include "icodestylepreferences.h"
+#include "jsoneditor.h"
 #include "linenumberfilter.h"
 #include "markdowneditor.h"
 #include "outlinefactory.h"
@@ -76,6 +77,7 @@ public:
 
     PlainTextEditorFactory plainTextEditorFactory;
     MarkdownEditorFactory markdownEditorFactory;
+    JsonEditorFactory jsonEditorFactory;
 };
 
 static TextEditorPlugin *m_instance = nullptr;