eventhandler.nim

import tables, hashes, json

type
    BaseEvent* = object of RootObj
        name*: string
    ReadyEvent* = object of BaseEvent
        readyPayload*: JsonNode

proc hash[T: object](o: T): Hash =
    for k, v in o.fieldPairs: 
        result = result !& v.hash
    result = !$result

# Table storing all the event listeners
let eventListeners = newTable[BaseEvent, seq[proc(event: BaseEvent)]]()

proc registerEventListener*[T: BaseEvent](event: T, listener: proc(event: T)) =
    when (eventListeners.hasKey(event)):
        var listeners = eventListeners[event]
        listeners.add(listener)
    else:
        let tmp = @[listener]
        eventListeners.add(event, tmp)

proc dispatchEvent*[T: BaseEvent](event: T) = 
    if (eventListeners.hasKey(event)):
        let listeners = eventListeners[event]
        for index, eventListener in listeners.pairs:
            echo "Dispatching event: ", BaseEvent(event).name
            eventListener(event)
    else:
        echo "No event listeners for event: ", BaseEvent(event).name