feat: Implement core functionality for DTC C/C++ IDE

- Added ProjectManager class to handle project operations including opening, closing, building, and running projects.
- Introduced SyntaxHighlighter class for syntax highlighting in C and C++ files.
- Developed TerminalWidget for command execution and output display.
- Created TextEditor with line numbering and auto-indentation features.
- Established main application entry point in main.cpp.
- Designed UI layout for MainWindow using Qt Designer.

include/FileTreeWidget.h

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <QtWidgets/QTreeWidget>
+#include <QtWidgets/QTreeWidgetItem>
+#include <QtWidgets/QMenu>
+#include <QtCore/QFileSystemWatcher>
+#include <QtCore/QDir>
+
+class FileTreeWidget : public QTreeWidget
+{
+    Q_OBJECT
+
+public:
+    explicit FileTreeWidget(QWidget *parent = nullptr);
+    ~FileTreeWidget();
+
+    void setRootPath(const QString &path);
+    QString rootPath() const;
+    
+    void refreshTree();
+
+signals:
+    void fileSelected(const QString &filePath);
+    void fileDoubleClicked(const QString &filePath);
+    void directorySelected(const QString &dirPath);
+
+private slots:
+    void onItemClicked(QTreeWidgetItem *item, int column);
+    void onItemDoubleClicked(QTreeWidgetItem *item, int column);
+    void onCustomContextMenu(const QPoint &point);
+    void onDirectoryChanged(const QString &path);
+    void newFile();
+    void newFolder();
+    void deleteItem();
+    void renameItem();
+
+private:
+    void populateTree(const QString &path, QTreeWidgetItem *parent = nullptr);
+    void setupContextMenu();
+    QString getItemPath(QTreeWidgetItem *item) const;
+    bool isDirectory(QTreeWidgetItem *item) const;
+
+    QString m_rootPath;
+    QFileSystemWatcher *m_fileWatcher;
+    QMenu *m_contextMenu;
+    QTreeWidgetItem *m_contextItem;
+};

include/MainWindow.h

@@ -0,0 +1,65 @@
+#pragma once
+
+#include <QtWidgets/QMainWindow>
+#include <QtWidgets/QMenuBar>
+#include <QtWidgets/QToolBar>
+#include <QtWidgets/QStatusBar>
+#include <QtWidgets/QSplitter>
+#include <QtWidgets/QTabWidget>
+#include <QtWidgets/QVBoxLayout>
+#include <QtWidgets/QHBoxLayout>
+#include <QtWidgets/QFileDialog>
+#include <QtWidgets/QMessageBox>
+#include <QtCore/QSettings>
+
+class TextEditor;
+class FileTreeWidget;
+class TerminalWidget;
+class ProjectManager;
+
+class MainWindow : public QMainWindow
+{
+    Q_OBJECT
+
+public:
+    MainWindow(QWidget *parent = nullptr);
+    ~MainWindow();
+
+private slots:
+    void newFile();
+    void openFile();
+    void saveFile();
+    void saveAsFile();
+    void openProject();
+    void buildProject();
+    void runProject();
+    void debugProject();
+    void showAbout();
+    void toggleTheme();
+
+private:
+    void setupUI();
+    void setupMenus();
+    void setupToolbar();
+    void setupStatusBar();
+    void connectSignals();
+    void loadSettings();
+    void saveSettings();
+
+    // UI Components
+    QSplitter *m_centralSplitter;
+    QSplitter *m_leftSplitter;
+    QTabWidget *m_editorTabs;
+    FileTreeWidget *m_fileTree;
+    TerminalWidget *m_terminal;
+    
+    // Managers
+    ProjectManager *m_projectManager;
+    
+    // Settings
+    QSettings *m_settings;
+    bool m_darkTheme;
+    
+    // Current file
+    QString m_currentFilePath;
+};

include/ProjectManager.h

@@ -0,0 +1,66 @@
+#pragma once
+
+#include <QtCore/QObject>
+#include <QtCore/QString>
+#include <QtCore/QDir>
+#include <QtCore/QFileInfo>
+#include <QtCore/QProcess>
+
+class ProjectManager : public QObject
+{
+    Q_OBJECT
+
+public:
+    explicit ProjectManager(QObject *parent = nullptr);
+    ~ProjectManager();
+
+    bool openProject(const QString &projectPath);
+    void closeProject();
+    
+    QString projectPath() const;
+    QString projectName() const;
+    bool hasProject() const;
+    
+    bool isCMakeProject() const;
+    bool isQMakeProject() const;
+    
+    void buildProject();
+    void cleanProject();
+    void configureProject();
+    void runProject();
+    
+    QString buildDirectory() const;
+    QString sourceDirectory() const;
+
+signals:
+    void projectOpened(const QString &projectPath);
+    void projectClosed();
+    void buildStarted();
+    void buildFinished(bool success);
+    void buildOutput(const QString &output);
+
+private slots:
+    void onBuildProcessFinished(int exitCode, QProcess::ExitStatus exitStatus);
+    void onBuildProcessError(QProcess::ProcessError error);
+    void onBuildOutput();
+
+private:
+    void detectProjectType();
+    void setupBuildDirectory();
+    QString findCMakeListsFile(const QString &directory) const;
+    QString findQMakeFile(const QString &directory) const;
+
+    QString m_projectPath;
+    QString m_projectName;
+    QString m_buildDirectory;
+    
+    enum ProjectType {
+        Unknown,
+        CMake,
+        QMake
+    };
+    ProjectType m_projectType;
+    
+    QProcess *m_buildProcess;
+    bool m_isBuilding;
+};

include/SyntaxHighlighter.h

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <QtGui/QSyntaxHighlighter>
+#include <QtGui/QTextDocument>
+#include <QtGui/QTextCharFormat>
+#include <QtCore/QRegularExpression>
+
+class SyntaxHighlighter : public QSyntaxHighlighter
+{
+    Q_OBJECT
+
+public:
+    explicit SyntaxHighlighter(QTextDocument *parent = nullptr);
+    ~SyntaxHighlighter();
+
+    void setLanguage(const QString &language);
+    QString language() const;
+
+protected:
+    void highlightBlock(const QString &text) override;
+
+private:
+    struct HighlightingRule
+    {
+        QRegularExpression pattern;
+        QTextCharFormat format;
+    };
+    QVector<HighlightingRule> m_highlightingRules;
+
+    void setupCppHighlighting();
+    void setupCHighlighting();
+    void setupCommonRules();
+    
+    QTextCharFormat m_keywordFormat;
+    QTextCharFormat m_classFormat;
+    QTextCharFormat m_singleLineCommentFormat;
+    QTextCharFormat m_multiLineCommentFormat;
+    QTextCharFormat m_quotationFormat;
+    QTextCharFormat m_functionFormat;
+    QTextCharFormat m_numberFormat;
+    QTextCharFormat m_preprocessorFormat;
+
+    QRegularExpression m_commentStartExpression;
+    QRegularExpression m_commentEndExpression;
+    
+    QString m_language;
+};

include/TerminalWidget.h

@@ -0,0 +1,58 @@
+#pragma once
+
+#include <QtWidgets/QWidget>
+#include <QtWidgets/QTextEdit>
+#include <QtWidgets/QLineEdit>
+#include <QtWidgets/QVBoxLayout>
+#include <QtWidgets/QHBoxLayout>
+#include <QtWidgets/QPushButton>
+#include <QtCore/QProcess>
+#include <QtCore/QTimer>
+
+class TerminalWidget : public QWidget
+{
+    Q_OBJECT
+
+public:
+    explicit TerminalWidget(QWidget *parent = nullptr);
+    ~TerminalWidget();
+
+    void setWorkingDirectory(const QString &directory);
+    QString workingDirectory() const;
+    
+    void executeCommand(const QString &command);
+    void clear();
+    
+    void showBuildOutput();
+    void showRunOutput();
+
+signals:
+    void commandFinished(int exitCode);
+
+private slots:
+    void onCommandEntered();
+    void onProcessFinished(int exitCode, QProcess::ExitStatus exitStatus);
+    void onProcessError(QProcess::ProcessError error);
+    void onProcessOutput();
+    void updatePrompt();
+
+private:
+    void setupUI();
+    void setupProcess();
+    void appendOutput(const QString &text, const QColor &color = Qt::white);
+    void appendPrompt();
+
+    QTextEdit *m_output;
+    QLineEdit *m_input;
+    QPushButton *m_clearButton;
+    
+    QProcess *m_process;
+    QString m_workingDirectory;
+    QString m_currentPrompt;
+    
+    // Colors for different output types
+    QColor m_normalColor;
+    QColor m_errorColor;
+    QColor m_successColor;
+    QColor m_promptColor;
+};

include/TextEditor.h

@@ -0,0 +1,77 @@
+#pragma once
+
+#include <QtWidgets/QPlainTextEdit>
+#include <QtCore/QTextStream>
+#include <QtGui/QTextDocument>
+#include <QtGui/QTextCursor>
+#include <QtGui/QKeyEvent>
+#include <QtCore/QTimer>
+
+class SyntaxHighlighter;
+
+class TextEditor : public QPlainTextEdit
+{
+    Q_OBJECT
+    friend class LineNumberArea;
+
+public:
+    explicit TextEditor(QWidget *parent = nullptr);
+    ~TextEditor();
+
+    void setFilePath(const QString &filePath);
+    QString filePath() const;
+    
+    bool isModified() const;
+    void setModified(bool modified);
+    
+    bool loadFile(const QString &filePath);
+    bool saveFile();
+    bool saveAsFile(const QString &filePath);
+
+    void setLineNumberAreaWidth(int width);
+    void updateLineNumberArea(const QRect &rect, int dy);
+
+signals:
+    void fileModified(bool modified);
+    void cursorPositionChanged(int line, int column);
+
+protected:
+    void keyPressEvent(QKeyEvent *event) override;
+    void paintEvent(QPaintEvent *event) override;
+    void resizeEvent(QResizeEvent *event) override;
+
+private slots:
+    void highlightCurrentLine();
+    void updateCursorPosition();
+    void autoIndent();
+
+private:
+    void setupEditor();
+    void updateLineNumberAreaWidth(int newBlockCount);
+
+public:
+    int lineNumberAreaWidth();
+
+    QString m_filePath;
+    bool m_isModified;
+    SyntaxHighlighter *m_syntaxHighlighter;
+    QWidget *m_lineNumberArea;
+    QTimer *m_autoSaveTimer;
+};
+
+// Line number area widget
+class LineNumberArea : public QWidget
+{
+public:
+    LineNumberArea(TextEditor *editor) : QWidget(editor), m_textEditor(editor) {}
+
+    QSize sizeHint() const override {
+        return QSize(m_textEditor->lineNumberAreaWidth(), 0);
+    }
+
+protected:
+    void paintEvent(QPaintEvent *event) override;
+
+private:
+    TextEditor *m_textEditor;
+};