module main
import os
import time

fn main() {
    current_dir := 'C:\\'
    mut scanner :=new_scanner(12)
	scanner.do_scan(current_dir)
}


fn new_scanner(max_worker_count int) &Scanner{
	return &Scanner{
		max_worker: max_worker_count
	}
}


struct Scanner{
mut:
	max_worker int = 32
	worker_count int
	search_request chan string
	work_done chan bool
}


fn (mut s Scanner)scanner(path string,is_master bool){
	items := os.ls(path) or {
        println('列出目录失败: $err\n$path')
		s.work_done <- true
        return
    }

    for item in items {
        full_path := os.join_path(path, item)
        if os.is_dir(full_path) {
            if s.worker_count < s.max_worker{
				s.search_request <- full_path
			}else{
				s.scanner(full_path,false)
			}
        } else {
            println('$full_path')
        }
    }
	if is_master{
		s.work_done <- true
	}
}


fn (mut s Scanner)do_scan(path string){
	start := time.now()
    
	s.worker_count = 1
	go s.scanner(path,true)
	s.watting_for_workers()

	end := time.now()
    duration := end - start
    println('耗时: ${duration.seconds()} 秒')
}


fn (mut s Scanner)watting_for_workers(){
	for {
		select {
			path := <- s.search_request {
				s.worker_count++
				go s.scanner(path,true)
			}
			_ :=<- s.work_done{
				s.worker_count--
				if s.worker_count == 0{
					return
				}
			}
		}
	}
}