v/vlib/eventbus/eventbus.v

124 lines
2.9 KiB
V

module eventbus
pub type EventHandlerFn = fn (receiver voidptr, args voidptr, sender voidptr)
pub struct Publisher {
mut:
registry &Registry
}
pub struct Subscriber {
mut:
registry &Registry
}
struct Registry {
mut:
events []EventHandler
}
struct EventHandler {
name string
handler EventHandlerFn
receiver voidptr = voidptr(0)
once bool
}
pub struct EventBus {
pub mut:
registry &Registry
publisher &Publisher
subscriber &Subscriber
}
pub fn new() &EventBus {
registry := &Registry{
events: []
}
return &EventBus{registry, &Publisher{registry}, &Subscriber{registry}}
}
// EventBus Methods
pub fn (eb &EventBus) publish(name string, sender voidptr, args voidptr) {
mut publisher := eb.publisher
publisher.publish(name, sender, args)
}
pub fn (eb &EventBus) clear_all() {
mut publisher := eb.publisher
publisher.clear_all()
}
pub fn (eb &EventBus) has_subscriber(name string) bool {
return eb.registry.check_subscriber(name)
}
// Publisher Methods
fn (mut pb Publisher) publish(name string, sender voidptr, args voidptr) {
for event in pb.registry.events {
if event.name == name {
event.handler(event.receiver, args, sender)
}
}
pb.registry.events = pb.registry.events.filter(!(it.name == name && it.once))
}
fn (mut p Publisher) clear_all() {
p.registry.events.clear()
}
// Subscriber Methods
pub fn (mut s Subscriber) subscribe(name string, handler EventHandlerFn) {
s.registry.events << EventHandler{
name: name
handler: handler
}
}
pub fn (mut s Subscriber) subscribe_method(name string, handler EventHandlerFn, receiver voidptr) {
s.registry.events << EventHandler{
name: name
handler: handler
receiver: receiver
}
}
// unsubscribe_method unsubscribe a receiver for only one method
pub fn (mut s Subscriber) unsubscribe_method(name string, receiver voidptr) {
s.registry.events = s.registry.events.filter(!(it.name == name && it.receiver == receiver))
}
// unsubscribe_receiver unsubscribes a receiver from all events
pub fn (mut s Subscriber) unsubscribe_receiver(receiver voidptr) {
s.registry.events = s.registry.events.filter(it.receiver != receiver)
}
pub fn (mut s Subscriber) subscribe_once(name string, handler EventHandlerFn) {
s.registry.events << EventHandler{
name: name
handler: handler
once: true
}
}
pub fn (s &Subscriber) is_subscribed(name string) bool {
return s.registry.check_subscriber(name)
}
// is_subscribed_method checks whether a receiver was already subscribed for any events
pub fn (s &Subscriber) is_subscribed_method(name string, receiver voidptr) bool {
return s.registry.events.any(it.name == name && it.receiver == receiver)
}
pub fn (mut s Subscriber) unsubscribe(name string, handler EventHandlerFn) {
// v := voidptr(handler)
s.registry.events = s.registry.events.filter(!(it.name == name && it.handler == handler))
}
// Registry Methods
fn (r &Registry) check_subscriber(name string) bool {
return r.events.any(it.name == name)
}