package main

import (
	"fmt"
	"time"
)

func main() {
	messages := make(chan string, 1) // Buffered channel

	// Non-blocking send
	select {
	case messages <- "hello":
		fmt.Println("Sent 'hello' immediately.")
	default:
		fmt.Println("No space in channel for 'hello'.")
	}

	// Try to send again, it should succeed now
	messages <- "world"
	fmt.Println("Sent 'world' after previous non-blocking attempt.")

	// Non-blocking receive
	select {
	case msg := <-messages:
		fmt.Println("Received immediately:", msg)
	default:
		fmt.Println("No message available immediately.")
	}

	// Channel is empty now, try non-blocking receive again
	select {
	case msg := <-messages:
		fmt.Println("Received immediately:", msg)
	default:
		fmt.Println("No message available immediately (second try).")
	}

	// Simulate some work, then send a message that will be picked up
	fmt.Println("Waiting 100ms then sending another message...")
	time.Sleep(100 * time.Millisecond)
	messages <- "delayed"

	// A blocking receive to ensure the delayed message is processed
	msg := <-messages
	fmt.Println("Received blocking:", msg)
}