meshcore_py/README.md

# Python MeshCore

Python library for interacting with [MeshCore](https://meshcore.co.uk) companion radio nodes.

## Installation

```bash
pip install meshcore
```

## Quick Start

Connect to your device and send a message:

```python
import asyncio
from meshcore import MeshCore, EventType

async def main():
    # Connect to your device
    meshcore = await MeshCore.create_serial("/dev/ttyUSB0")
    
    # Get your contacts
    result = await meshcore.commands.get_contacts()
    if result.type == EventType.ERROR:
        print(f"Error getting contacts: {result.payload}")
        return
        
    contacts = result.payload
    print(f"Found {len(contacts)} contacts")
    
    # Send a message to the first contact
    if contacts:
        # Get the first contact
        contact = next(iter(contacts.items()))[1]
        
        # Pass the contact object directly to send_msg
        result = await meshcore.commands.send_msg(contact, "Hello from Python!")
        
        if result.type == EventType.ERROR:
            print(f"Error sending message: {result.payload}")
        else:
            print("Message sent successfully!")
    
    await meshcore.disconnect()

asyncio.run(main())
```

## Development Setup

To set up for development:

```bash
# Create and activate virtual environment
python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate

# Install in development mode
pip install -e .

# Run examples
python examples/pubsub_example.py -p /dev/ttyUSB0
```

## Usage Guide

### Command Return Values

All command methods in MeshCore return an `Event` object that contains both the event type and its payload. This allows for consistent error handling and type checking:

```python
# Command result structure
result = await meshcore.commands.some_command()

# Check if the command was successful or resulted in an error
if result.type == EventType.ERROR:
    # Handle error case
    print(f"Command failed: {result.payload}")
else:
    # Handle success case - the event type will be specific to the command
    # (e.g., EventType.DEVICE_INFO, EventType.CONTACTS, EventType.MSG_SENT)
    print(f"Command succeeded with event type: {result.type}")
    # Access the payload data
    data = result.payload
```

Common error handling pattern:

```python
result = await meshcore.commands.send_msg(contact, "Hello!")
if result.type == EventType.ERROR:
    print(f"Error sending message: {result.payload}")
else:
    # For send_msg, a successful result will have type EventType.MSG_SENT
    print(f"Message sent with expected ack: {result.payload['expected_ack'].hex()}")
```

### Connecting to Your Device

Connect via Serial, BLE, or TCP:

```python
# Serial connection
meshcore = await MeshCore.create_serial("/dev/ttyUSB0", 115200, debug=True)

# BLE connection (scans for devices if address not provided)
meshcore = await MeshCore.create_ble("12:34:56:78:90:AB")

# TCP connection
meshcore = await MeshCore.create_tcp("192.168.1.100", 4000)
```

#### Auto-Reconnect and Connection Events

Enable automatic reconnection when connections are lost:

```python
# Enable auto-reconnect with custom retry limits
meshcore = await MeshCore.create_tcp(
    "192.168.1.100", 4000,
    auto_reconnect=True,
    max_reconnect_attempts=5
)

# Subscribe to connection events
async def on_connected(event):
    print(f"Connected: {event.payload}")
    if event.payload.get('reconnected'):
        print("Successfully reconnected!")

async def on_disconnected(event):
    print(f"Disconnected: {event.payload['reason']}")
    if event.payload.get('max_attempts_exceeded'):
        print("Max reconnection attempts exceeded")

meshcore.subscribe(EventType.CONNECTED, on_connected)
meshcore.subscribe(EventType.DISCONNECTED, on_disconnected)

# Check connection status
if meshcore.is_connected:
    print("Device is currently connected")
```

**Auto-reconnect features:**
- Exponential backoff (1s, 2s, 4s, 8s max delay)
- Configurable retry limits (default: 3 attempts)
- Automatic disconnect detection (especially useful for TCP connections)
- Connection events with detailed information

### Using Commands (Synchronous Style)

Send commands and wait for responses:

```python
# Get device information
result = await meshcore.commands.send_device_query()
if result.type == EventType.ERROR:
    print(f"Error getting device info: {result.payload}")
else:
    print(f"Device model: {result.payload['model']}")

# Get list of contacts
result = await meshcore.commands.get_contacts()
if result.type == EventType.ERROR:
    print(f"Error getting contacts: {result.payload}")
else:
    contacts = result.payload
    for contact_id, contact in contacts.items():
        print(f"Contact: {contact['adv_name']} ({contact_id})")

# Send a message (destination key in bytes)
result = await meshcore.commands.send_msg(dst_key, "Hello!")
if result.type == EventType.ERROR:
    print(f"Error sending message: {result.payload}")

# Setting device parameters
result = await meshcore.commands.set_name("My Device")
if result.type == EventType.ERROR:
    print(f"Error setting name: {result.payload}")
    
result = await meshcore.commands.set_tx_power(20)  # Set transmit power
if result.type == EventType.ERROR:
    print(f"Error setting TX power: {result.payload}")
```

### Finding Contacts

Easily find contacts by name or key:

```python
# Find a contact by name
contact = meshcore.get_contact_by_name("Bob's Radio")
if contact:
    print(f"Found Bob at: {contact['adv_lat']}, {contact['adv_lon']}")
    
# Find by partial key prefix
contact = meshcore.get_contact_by_key_prefix("a1b2c3")
```

### Event-Based Programming (Asynchronous Style)

Subscribe to events to handle them asynchronously:

```python
# Subscribe to incoming messages
async def handle_message(event):
    data = event.payload
    print(f"Message from {data['pubkey_prefix']}: {data['text']}")
    
subscription = meshcore.subscribe(EventType.CONTACT_MSG_RECV, handle_message)

# Subscribe to advertisements
async def handle_advert(event):
    print("Advertisement detected!")
    
meshcore.subscribe(EventType.ADVERTISEMENT, handle_advert)

# When done, unsubscribe
meshcore.unsubscribe(subscription)
```

#### Filtering Events by Attributes

Filter events based on their attributes to handle only specific ones:

```python
# Subscribe only to messages from a specific contact
async def handle_specific_contact_messages(event):
    print(f"Message from Alice: {event.payload['text']}")
    
contact = meshcore.get_contact_by_name("Alice")
if contact:
    alice_subscription = meshcore.subscribe(
        EventType.CONTACT_MSG_RECV,
        handle_specific_contact_messages,
        attribute_filters={"pubkey_prefix": contact["public_key"][:12]}
    )

# Send a message and wait for its specific acknowledgment
async def send_and_confirm_message(meshcore, dst_key, message):
    # Send the message and get information about the sent message
    sent_result = await meshcore.commands.send_msg(dst_key, message)
    
    # Extract the expected acknowledgment code from the message sent event
    if sent_result.type == EventType.ERROR:
        print(f"Error sending message: {sent_result.payload}")
        return False
        
    expected_ack = sent_result.payload["expected_ack"].hex()
    print(f"Message sent, waiting for ack with code: {expected_ack}")
    
    # Wait specifically for this acknowledgment
    result = await meshcore.wait_for_event(
        EventType.ACK,
        attribute_filters={"code": expected_ack},
        timeout=10.0
    )
    
    if result:
        print("Message confirmed delivered!")
        return True
    else:
        print("Message delivery confirmation timed out")
        return False
```

### Hybrid Approach (Commands + Events)

Combine command-based and event-based styles:

```python
import asyncio

async def main():
    # Connect to device
    meshcore = await MeshCore.create_serial("/dev/ttyUSB0")
    
    # Set up event handlers
    async def handle_ack(event):
        print("Message acknowledged!")
    
    async def handle_battery(event):
        print(f"Battery level: {event.payload}%")
    
    # Subscribe to events
    meshcore.subscribe(EventType.ACK, handle_ack)
    meshcore.subscribe(EventType.BATTERY, handle_battery)
    
    # Create background task for battery checking
    async def check_battery_periodically():
        while True:
            # Send command (returns battery level)
            result = await meshcore.commands.get_bat()
            if result.type == EventType.ERROR:
                print(f"Error checking battery: {result.payload}")
            else:
                print(f"Battery level: {result.payload.get('level', 'unknown')}%")
            await asyncio.sleep(60)  # Wait 60 seconds between checks
    
    # Start the background task
    battery_task = asyncio.create_task(check_battery_periodically())
    
    # Send manual command and wait for response
    await meshcore.commands.send_advert(flood=True)
    
    try:
        # Keep the main program running
        await asyncio.sleep(float('inf'))
    except asyncio.CancelledError:
        # Clean up when program ends
        battery_task.cancel()
        await meshcore.disconnect()

# Run the program
asyncio.run(main())
```

### Auto-Fetching Messages

Let the library automatically fetch incoming messages:

```python
# Start auto-fetching messages
await meshcore.start_auto_message_fetching()

# Just subscribe to message events - the library handles fetching
async def on_message(event):
    print(f"New message: {event.payload['text']}")
    
meshcore.subscribe(EventType.CONTACT_MSG_RECV, on_message)

# When done
await meshcore.stop_auto_message_fetching()
```

### Debug Mode

Enable debug logging for troubleshooting:

```python
# Enable debug mode when creating the connection
meshcore = await MeshCore.create_serial("/dev/ttyUSB0", debug=True)
```

This logs detailed information about commands sent and events received.

## Common Examples

### Sending Messages to Contacts

Commands that require a destination (`send_msg`, `send_login`, `send_statusreq`, etc.) now accept either:
- A string with the hex representation of a public key
- A contact object with a "public_key" field
- Bytes object (for backward compatibility)

```python
# Get contacts and send to a specific one
result = await meshcore.commands.get_contacts()
if result.type == EventType.ERROR:
    print(f"Error getting contacts: {result.payload}")
else:
    contacts = result.payload
    for key, contact in contacts.items():
        if contact["adv_name"] == "Alice":
            # Option 1: Pass the contact object directly
            result = await meshcore.commands.send_msg(contact, "Hello Alice!")
            if result.type == EventType.ERROR:
                print(f"Error sending message: {result.payload}")
            
            # Option 2: Use the public key string
            result = await meshcore.commands.send_msg(contact["public_key"], "Hello again Alice!")
            if result.type == EventType.ERROR:
                print(f"Error sending message: {result.payload}")
            
            # Option 3 (backward compatible): Convert the hex key to bytes
            dst_key = bytes.fromhex(contact["public_key"])
            result = await meshcore.commands.send_msg(dst_key, "Hello once more Alice!")
            if result.type == EventType.ERROR:
                print(f"Error sending message: {result.payload}")
            break

# You can also directly use a contact found by name
contact = meshcore.get_contact_by_name("Bob")
if contact:
    result = await meshcore.commands.send_msg(contact, "Hello Bob!")
    if result.type == EventType.ERROR:
        print(f"Error sending message: {result.payload}")
```

### Monitoring Channel Messages

```python
# Subscribe to channel messages
async def channel_handler(event):
    msg = event.payload
    print(f"Channel {msg['channel_idx']}: {msg['text']}")
    
meshcore.subscribe(EventType.CHANNEL_MSG_RECV, channel_handler)
```

## Examples in the Repo

Check the `examples/` directory for more:

- `pubsub_example.py`: Event subscription system with auto-fetching
- `serial_infos.py`: Quick device info retrieval
- `serial_msg.py`: Message sending and receiving
- `ble_t1000_infos.py`: BLE connections