package kaca

import (
	"log"
	"strconv"
	"strings"
)

type dispatcher struct {
	// Registered connections.
	connections map[*connection]bool
	broadcast   chan []byte
	sub         chan string
	pub         chan string
	register    chan *connection
	unregister  chan *connection
}

func NewDispatcher() *dispatcher {
	return &dispatcher{
		broadcast:   make(chan []byte),
		sub:         make(chan string),
		pub:         make(chan string),
		register:    make(chan *connection),
		unregister:  make(chan *connection),
		connections: make(map[*connection]bool),
	}
}

func (d *dispatcher) run() {
	for {
		select {
		case c := <-d.register:
			d.connections[c] = true
		case c := <-d.unregister:
			if _, ok := d.connections[c]; ok {
				delete(d.connections, c)
				close(c.send)
			}
		case m := <-d.broadcast:
			for c := range d.connections {
				select {
				case c.send <- m:
				default:
					close(c.send)
					delete(d.connections, c)
				}
			}
		case m := <-d.sub:
			msp := strings.Split(m, SPLIT_LINE)
			//subscribe message
			log.Println("sub->" + m)
			for c := range d.connections {
				if msp[0] == strconv.Itoa(int(c.cid)) {
					c.topics = append(c.topics, msp[1])
				}
			}

		case m := <-d.pub:
			//publish message
			msp := strings.Split(m, SPLIT_LINE)
			log.Println("pub->" + m)
			for c := range d.connections {
				for _, t := range c.topics {
					if t == msp[0] {
						select {
						case c.send <- []byte(msp[1]):
						default:
							close(c.send)
							delete(d.connections, c)
						}
						break
					}
				}
			}
		}
	}
}