# Project Proposal: Pear - P2P Terminal Chat

## Overview
Pear is a peer-to-peer command line messaging tool that enables users on a local network to discover each other and communicate through a terminal-based chat interface. Users can start a chat session with a single command, and others can join to participate in real-time messaging.

## MVP Requirements

### Core Features

#### 1. Command Line Interface
- **Start Session**: Single command to initialize and host a chat room
- **Join Session**: Command to discover and join existing chat rooms on the local network
- **Message Input**: Simple text input interface for typing messages
- **Message Display**: Real-time display of messages from all participants
- **Exit**: Clean exit functionality with proper connection cleanup

#### 2. Peer-to-Peer Networking
- **Network Discovery**: Automatic discovery of active chat sessions on the local network
- **Direct Connection**: Direct peer-to-peer connections without requiring a central server
- **Local Network Scope**: Communication limited to local network (LAN/WiFi) for MVP
- **Connection Management**: Handle peer connections, disconnections, and network changes

#### 3. Multi-User Messaging
- **Real-time Messaging**: Instant message delivery between all connected peers
- **User Identification**: Basic user identification (username/hostname) for message attribution
- **Message Broadcasting**: Messages sent by one user are delivered to all connected peers
- **Connection Status**: Basic indication of who is connected to the chat

#### 4. Terminal User Experience
- **Text-based Interface**: Clean, readable terminal interface
- **Message History**: Scrollable message history during the session
- **Input/Output Separation**: Clear distinction between message display and input areas

## Technical Architecture

### Core Components

#### 1. Network Layer
- **Protocol**: UDP for discovery, TCP for messaging
- **Discovery Service**: Broadcast/multicast for finding active sessions
- **Connection Handler**: Manage peer connections and message routing

#### 2. CLI Interface
- **Command Parser**: Handle command line arguments and options
- **Terminal UI**: Basic terminal interface for message display and input
- **Input Handler**: Capture and process user input

#### 3. Message System
- **Message Format**: Simple text-based message protocol
- **Message Routing**: Distribute messages to all connected peers
- **Session Management**: Track active users and connection states

### Minimal Command Structure
```
pear start [session-name]    # Start hosting a chat session
pear join [session-name]     # Join an existing session
pear list                    # List available sessions on network
```

## Implementation Scope

### What's Included (MVP)
- Basic P2P networking on local network
- Simple terminal chat interface
- Essential commands for starting/joining sessions
- Real-time message exchange between peers
- Basic user identification
- Clean connection handling

## Success Criteria

The MVP will be considered successful when:

1. **Discovery**: Users can discover active chat sessions on their local network
2. **Connection**: Multiple users can successfully join the same chat session
3. **Messaging**: Real-time bidirectional messaging works reliably between all participants
4. **Stability**: Connections remain stable during normal chat usage
5. **Usability**: The command line interface is intuitive and responsive

## Technical Considerations

### Language & Framework
- **Primary Language**: Choose based on networking capabilities and terminal handling
- **Networking**: Built-in socket libraries for P2P communication
- **CLI Framework**: Minimal dependencies for command parsing and terminal I/O

### Platform Support
- **Primary Target**: Unix-like systems (macOS, Linux)
- **Secondary**: Windows support through cross-platform libraries

### Performance Requirements
- **Latency**: Sub-second message delivery on local network
- **Capacity**: Support 5-10 concurrent users per session
- **Resource Usage**: Minimal CPU and memory footprint

## Risks & Mitigation

### Technical Risks
- **Network Discovery Issues**: Implement fallback discovery methods
- **Connection Reliability**: Add automatic reconnection logic
- **Cross-Platform Compatibility**: Test early on target platforms

### Scope Risks
- **Feature Creep**: Maintain strict focus on MVP requirements
- **Over-Engineering**: Keep implementation simple and functional
