Emoji CLI - Clipboard Transcoder

A command-line application that demonstrates clipboard functionality with the emoji_transcoder package. Hide messages in clipboard text using Unicode variation selectors.

Features

• Command-line interface with comprehensive argument parsing.
• Interactive mode when no arguments are provided.
• Multiple encoding methods including safe ZWJ encoding.
• Batch operations for encoding multiple messages.
• Statistics and analysis of clipboard content.
• Cross-platform clipboard support via daniboard.

Installation

1. Navigate to the CLI directory:

cd example/emoji_cli

2. Install dependencies:

dart pub get

3. Run the application:

dart run bin/main.dart

Or install globally:

dart pub global activate --source path .
emoji_cli --help

Usage

Command Line Mode

# Encode a message into an emoji.
emoji_cli --encode "😊:Hello World"

# Decode first message from clipboard.
emoji_cli --decode

# Decode all messages from clipboard.
emoji_cli --decode-all

# Check if clipboard contains hidden data.
emoji_cli --check

# Show clipboard statistics.
emoji_cli --stats

# Show raw clipboard content.
emoji_cli --raw

# Show only visible characters.
emoji_cli --visible

# Set clipboard to plain text.
emoji_cli --set "Plain text message"

# Encode multiple messages.
emoji_cli --encode-multiple "😊:hello,🌟:world,🔐:secret"

Interactive Mode

Run without arguments to enter interactive mode:

emoji_cli

Available interactive commands:

• encode <base> <message> - Encode message into base character.
• decode - Decode first message from clipboard.
• decode-all - Decode all messages from clipboard.
• check - Check if clipboard has hidden data.
• stats - Show clipboard statistics.
• raw - Show raw clipboard content.
• visible - Show only visible characters.
• set <text> - Set clipboard to plain text.
• clear - Clear clipboard.
• help - Show help.
• quit - Exit.

Examples

Basic Encoding/Decoding

# Encode a secret message
$ emoji_cli --encode "😊:This is a secret message"
✓ Encoded "This is a secret message" into 😊 and copied to clipboard

# Check what's in clipboard (looks normal)
$ emoji_cli --raw
Raw clipboard content:
"😊"

# But it contains hidden data
$ emoji_cli --check
✓ Clipboard contains hidden data

# Decode the hidden message
$ emoji_cli --decode
Decoded message: This is a secret message

Multiple Messages

# Encode multiple messages
$ emoji_cli --encode-multiple "😊:hello,🌟:world,🔐:secret"
✓ Encoded 3 messages and copied to clipboard
  😊: "hello"
  🌟: "world"
  🔐: "secret"

# Decode all messages
$ emoji_cli --decode-all
Found 3 hidden message(s):
  1. 😊: "hello"
  2. 🌟: "world"
  3. 🔐: "secret"

Statistics

$ emoji_cli --stats
Clipboard Statistics:
  Total length: 27 characters
  Visible length: 3 characters
  Hidden bytes: 24
  Message count: 3

Interactive Session

$ emoji_cli
🔤 Emoji Transcoder CLI - Interactive Mode
Hide messages in clipboard text using emoji steganography
Type "help" for commands or "quit" to exit.

emoji_cli> encode 🎉 Happy New Year!
✓ Encoded "Happy New Year!" into 🎉

emoji_cli> stats
Stats: 1 visible, 15 hidden, 1 messages

emoji_cli> decode
Decoded: "Happy New Year!"

emoji_cli> quit
Goodbye! 👋

API Reference

The CLI uses the ClipboardTranscoder class which provides:

Encoding Methods

• encodeAndWriteToClipboard(baseChar, message) - Basic encoding.
• encodeMultipleAndWriteToClipboard(messages) - Multiple messages.

Decoding Methods

• readAndDecodeFromClipboard() - Decode first message.
• readAndDecodeAllFromClipboard() - Decode all messages.

Utility Methods

• clipboardHasHiddenData() - Check for hidden data.
• getClipboardStats() - Get statistics.
• getRawClipboardText() - Get raw content.
• setRawClipboardText(text) - Set raw content.
• getVisibleText(text) - Extract visible characters.

Dependencies

• emoji_transcoder - Core encoding/decoding functionality.
• daniboard - Cross-platform clipboard access.
• args - Command-line argument parsing.

License

This project is licensed under the MIT License - see the LICENSE file for details.