from functools import lru_cache

from src.shared.events.base import Event

from src.shared.events.handler import EventHandler

class EventBus:

"""

General-purpose event bus for publishing and subscribing to events.

Supports multiple handlers per event type.

"""

def __init__(self):

self._handlers: dict[str, list[EventHandler]] = {}

def subscribe(self, event_type: str, handler: EventHandler):

"""Register a handler for a specific event type"""

if event_type not in self._handlers:

self._handlers[event_type] = []

self._handlers[event_type].append(handler)

def unsubscribe(self, event_type: str, handler: EventHandler):

"""Remove a handler for a specific event type"""

if event_type in self._handlers:

self._handlers[event_type] = [

h for h in self._handlers[event_type] if h != handler

]

async def publish(self, event: Event):

"""Publish an event to all subscribed handlers"""

event_type = event.event_type

handlers = self._handlers.get(event_type, [])

for handler in handlers:

try:

await handler.handle(event)

except Exception as e:

# Log error but don't stop other handlers

print(

f"Error in handler {handler.__class__.__name__} for event {event_type}: {e}"

)

# In production, use proper logging and error tracking (Sentry, etc.)

@lru_cache

def get_event_bus() -> EventBus:

return EventBus()