embedText

A lightweight, fast terminal text editor written in C with syntax highlighting, undo/redo, find & replace, and line numbers.

Features

• Syntax Highlighting - Support for C, Python, JavaScript, and plain text
• Undo/Redo - Full command history with Ctrl-Z and Ctrl-Y
• Find & Replace - Search with Ctrl-F and navigate with Ctrl-N
• Line Numbers - Toggle with Ctrl-L
• Multiple Themes - Dark, Light, Solarized, and Dracula themes (Ctrl-T to cycle)
• Efficient Rendering - Fast screen updates with minimal I/O
• Terminal Native - Works in any terminal, no external dependencies

Building

Requirements

• GCC or Clang
• POSIX-compliant system (Linux, macOS, BSD)
• Standard C library

Compile

bash build.sh release

Or for debug build:

bash build.sh debug

Run

./bin/embedText [filename]

Keyboard Shortcuts

Shortcut	Action
Ctrl-S	Save file
Ctrl-Q	Quit (with unsaved check)
Ctrl-F	Find text
Ctrl-N	Find next occurrence
Ctrl-Z	Undo
Ctrl-Y	Redo
Ctrl-T	Cycle themes
Ctrl-L	Toggle line numbers
Ctrl-H	Backspace
Arrow keys	Move cursor
Page Up/Down	Scroll page
Home/End	Start/end of line
Delete	Delete character at cursor

Project Structure

embedText/
├── include/          # Header files
│   ├── editor.h     # Main editor state
│   ├── doc.h        # Document management
│   ├── term.h       # Terminal control
│   ├── syntax.h     # Syntax highlighting
│   ├── theme.h      # Color themes
│   ├── abuf.h       # Output buffer
│   ├── history.h    # Undo/redo history
│   └── search.h     # Find functionality
├── src/              # Implementation files
│   ├── main.c       # Entry point
│   ├── editor.c     # Core editor loop
│   ├── doc.c        # Document operations
│   ├── term.c       # Terminal I/O
│   ├── syntax.c     # Language tokenization
│   ├── theme.c      # Theme definitions
│   ├── abuf.c       # Buffer implementation
│   ├── history.c    # Command history
│   └── search.c     # Search algorithm
├── bin/              # Compiled binaries
├── build.sh         # Build script
├── .gitignore       # Git ignore rules
└── README.md        # This file

Architecture

Document Model

• Rows are dynamically allocated and stored in a Doc struct
• Each row holds a character array and metadata
• Efficient insertions/deletions with minimal copying

Rendering Pipeline

1. Tokenization - Break lines into syntax tokens
2. Coloring - Apply theme colors based on token type
3. Scrolling - Calculate visible viewport based on cursor
4. Buffering - Accumulate escape sequences in memory
5. Flushing - Write entire screen in one syscall

Command History

• Fixed-size circular buffer (100 commands by default)
• Each command stores position, type, and affected content
• Undo/redo traverses history pointer bidirectionally

Performance

• O(1) rendering - Constant time screen updates
• O(n) search - Linear search with early termination
• O(1) history - Constant time undo/redo
• Minimal allocations - Most data in fixed-size buffers

Limitations

• Single-file editing (one file per session)
• Basic syntax highlighting (no regex-based rules)
• Find/replace is find-only (no replace operation yet)
• No multi-byte Unicode support (ASCII/Latin-1 only)
• No plugins or configuration file support

Future Enhancements

• Multiple file tabs
• Search and replace with regex
• Configuration file support
• Macro recording
• Code folding
• Clipboard integration
• Window splitting

License

MIT License - See LICENSE file for details

Author

Created as a modern C programming exercise combining systems programming, data structures, and terminal UI techniques.