package main

import (
	"context"
	"fmt"
	"sync"
	"time"
)

func main() {
	fields := []int{5, 3, 2, 6, 4} // Sleep second
	wg := sync.WaitGroup{}
	wg.Add( len(fields) )

	timeout := 5

	MAXROUTINE := 10
	dataChan := make(chan int, MAXROUTINE)
	stopChan := make(chan bool)
	defer close(stopChan)
	waitChan := make(chan bool)
	timeoutCtx, cancel := context.WithTimeout(context.TODO(), time.Duration(timeout) * time.Second)
	defer cancel()

	// consumer worker
	for i := 0; i < MAXROUTINE; i++ {
		// worker
		go func(n int) {
		L:
			for {
				select {
				case field := <-dataChan:
					time.Sleep(time.Second * time.Duration(field))
					fmt.Println("Field", field)
					wg.Done()
				case <-stopChan:
					break L
				}
			}
		}(i)
	}

	// provider
	go func() {
		for i := 0; i < len(fields); i++ {
			dataChan <- fields[i]
		}
	}()

	// wait
	go func() {
		wg.Wait()
		waitChan <- true
	}()

	select {
	case <-waitChan:
		fmt.Println("Run finished.")
	case <-timeoutCtx.Done():
		fmt.Println("Run timeout.")
	}
}