/*
Copyright 2013 CoreOS Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package web

type hub struct {
	// status
	open bool

	// Registered connections.
	connections map[*connection]bool

	// Inbound messages from the connections.
	broadcast chan string

	// Register requests from the connections.
	register chan *connection

	// Unregister requests from connections.
	unregister chan *connection
}

var h = hub{
	open:        false,
	broadcast:   make(chan string),
	register:    make(chan *connection),
	unregister:  make(chan *connection),
	connections: make(map[*connection]bool),
}

func Hub() *hub {
	return &h
}

func HubOpen() bool {
	return h.open
}

func (h *hub) run() {
	h.open = true
	for {
		select {
		case c := <-h.register:
			h.connections[c] = true
		case c := <-h.unregister:
			delete(h.connections, c)
			close(c.send)
		case m := <-h.broadcast:
			for c := range h.connections {
				select {
				case c.send <- m:
				default:
					delete(h.connections, c)
					close(c.send)
					go c.ws.Close()
				}
			}
		}
	}
}

func (h *hub) Send(msg string) {
	h.broadcast <- msg
}