package main

import (
	"bytes"
	"context"
	"encoding/json"
	"io"
	"log"
	"net/http"
	"os"
	"sync"
)

const URL = `http://localhost:5000/download`

type Item struct {
	Link string `json:"link"`
}

var wg sync.WaitGroup

func main() {
	log.SetFlags(log.Lmicroseconds)

	for _, url := range os.Args[1:] {
		log.Printf("Downloading %s", url)
		wg.Add(1)
		go Download(url)
	}
	wg.Wait()
}

func Download(url string) {
	defer wg.Done()

	req, err := http.NewRequestWithContext(context.Background(), "POST", URL, nil)
	if err != nil {
		log.Printf("Error creating POST request: %++v", err)
		return
	}
	req.Header.Set("Content-Type", "application/json")

	item := new(Item)
	item.Link = url

	body, err := json.Marshal(item)
	if err != nil {
		log.Printf("Error marshalling subscription body: %++v", err)
		return
	}
	req.Body = io.NopCloser(bytes.NewReader(body))

	client := http.Client{}
	res, err := client.Do(req)
	if err != nil {
		log.Printf("Error sending POST request: %++v", err)
		return
	}
	defer res.Body.Close()

	if res.StatusCode != http.StatusOK {
		log.Printf("Non-OK HTTP status: %d", res.StatusCode)

		body, err = io.ReadAll(res.Body)
		if err != nil {
			log.Printf("Error reading response body: %++v", err)
			return
		}
		return
	} else {
		log.Printf("Enqueued %s", url)
	}
}