package main 

import (
	"gomod.cblgh.org/iroh-tracker/stack"
	"fmt"
)

const MAX_TOPICS = 5
const MAX_PEERS = 4
var topicToPeers map[string]*stack.Stack
var topics *stack.Stack

func main() {
	topics = stack.NewStack(MAX_TOPICS)
	topicToPeers = make(map[string]*stack.Stack)
	fmt.Println("topics to peers", topicToPeers)
	fmt.Println("topics slice", topics)
	visit("hello.topic", "alex")
	visit("nice.topic", "alex")
	visit("good.topic", "alex")
	visit("newer.topic", "alex")
	visit("great.topic", "alex")
	visit("newest.topic", "alex") // should evict hello.topic
	visit("newest.topic", "alex1") 
	visit("newest.topic", "alex2")
	visit("newest.topic", "alex3")
	visit("newest.topic", "alex4")
	fmt.Printf("%+v\n", topicToPeers)
	fmt.Printf("%+v\n", topicToPeers["newest.topic"])
}

func visit(topic, peer string) {
	peers, exists := topicToPeers[topic]

	if !exists {
		peers = stack.NewStack(MAX_PEERS)
		topicToPeers[topic] = peers
		fmt.Println("topic does not exist")
	}
	evicted := topics.Push(topic)
	peers.Push(peer)
	// forget about the old topic
	if evicted != "" {
		delete(topicToPeers, evicted)
	}
}