feat: Add side by side refactor widget (#276)

widgets/ContextExtractor.hpp

@@ -0,0 +1,125 @@
+/* 
+ * Copyright (C) 2025 Petr Mironychev
+ *
+ * This file is part of QodeAssist.
+ *
+ * QodeAssist is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * QodeAssist is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with QodeAssist. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <QString>
+#include <QStringList>
+#include <QTextBlock>
+#include <QTextDocument>
+
+#include <texteditor/texteditor.h>
+#include <utils/textutils.h>
+
+namespace QodeAssist {
+
+class ContextExtractor
+{
+public:
+    static QString extractBefore(TextEditor::TextEditorWidget *editor,
+                                  const Utils::Text::Range &range,
+                                  int lineCount)
+    {
+        if (!editor || lineCount <= 0) {
+            return QString();
+        }
+
+        QTextDocument *doc = editor->document();
+        int startLine = range.begin.line;
+        int contextStartLine = qMax(1, startLine - lineCount);
+
+        QStringList contextLines;
+        for (int line = contextStartLine; line < startLine; ++line) {
+            QTextBlock block = doc->findBlockByNumber(line - 1);
+            if (block.isValid()) {
+                contextLines.append(block.text());
+            }
+        }
+
+        return contextLines.join('\n');
+    }
+
+    static QString extractAfter(TextEditor::TextEditorWidget *editor,
+                                const Utils::Text::Range &range,
+                                int lineCount)
+    {
+        if (!editor || lineCount <= 0) {
+            return QString();
+        }
+
+        QTextDocument *doc = editor->document();
+        int endLine = range.end.line;
+        int totalLines = doc->blockCount();
+        int contextEndLine = qMin(totalLines, endLine + lineCount);
+
+        QStringList contextLines;
+        for (int line = endLine + 1; line <= contextEndLine; ++line) {
+            QTextBlock block = doc->findBlockByNumber(line - 1);
+            if (block.isValid()) {
+                contextLines.append(block.text());
+            }
+        }
+
+        return contextLines.join('\n');
+    }
+
+    static QString extractLineContext(QTextDocument *doc, int position, bool before)
+    {
+        QTextCursor cursor(doc);
+        cursor.setPosition(position);
+
+        if (before) {
+            int posInBlock = cursor.positionInBlock();
+            cursor.movePosition(QTextCursor::StartOfBlock);
+            cursor.movePosition(QTextCursor::Right, QTextCursor::KeepAnchor, posInBlock);
+            return cursor.selectedText();
+        } else {
+            cursor.movePosition(QTextCursor::EndOfBlock, QTextCursor::KeepAnchor);
+            return cursor.selectedText();
+        }
+    }
+
+    static QStringList extractSurroundingLines(QTextDocument *doc, int position, int linesBefore, int linesAfter)
+    {
+        QTextCursor cursor(doc);
+        cursor.setPosition(position);
+        QTextBlock currentBlock = cursor.block();
+
+        QStringList result;
+
+        QTextBlock blockBefore = currentBlock.previous();
+        QStringList beforeLines;
+        for (int i = 0; i < linesBefore && blockBefore.isValid(); ++i) {
+            beforeLines.prepend(blockBefore.text());
+            blockBefore = blockBefore.previous();
+        }
+        result.append(beforeLines);
+
+        QTextBlock blockAfter = currentBlock.next();
+        for (int i = 0; i < linesAfter && blockAfter.isValid(); ++i) {
+            result.append(blockAfter.text());
+            blockAfter = blockAfter.next();
+        }
+
+        return result;
+    }
+};
+
+} // namespace QodeAssist
+