package main

import (
	"encoding/xml"
	"errors"
	"flag"
	"fmt"
	"net/http"
	"strings"
	"time"

	"github.com/hamcha/clessy/tg"
)

func assert(err error) {
	if err != nil {
		panic(err)
	}
}

var chatID *int
var lastPage string
var broker *tg.Broker
var apichat *tg.APIChat

const mspaRSS = "http://mspaintadventures.com/rss/rss.xml"
const timelayout = "Mon, 2 Jan 2006 15:04:05 -0700"

type Item struct {
	Title string `xml:"title"`
	Link  string `xml:"link"`
	Date  string `xml:"pubDate"`
}

type RSS struct {
	Items []Item `xml:"channel>item"`
}

func process(b *tg.Broker, update tg.APIMessage) {
	if update.Chat.ChatID == *chatID && *(update.Text) == "!start" {
		broker = b
		apichat = update.Chat
		broker.SendTextMessage(apichat, "Ok! Aspetto updates..", &update.MessageID)
	}
}

func advert(page Item) {
	date, _ := time.Parse(timelayout, page.Date)
	dateStr := date.Format("15:04:05")
	parts := strings.Split(page.Link, "p=")
	pagen := strings.Trim(parts[1], "0")
	text := "<b>Nuova pagina uscita!</b>\n\n#" + pagen + " - " + dateStr + "\n" + page.Title + "\n\n<a href=\"" + page.Link + "\">Clicca qui per leggerla</a>"
	broker.SendTextMessage(apichat, text, nil)
}

func startPolling(delay int64) {
	panicFn := func(err error) {
		broker.SendTextMessage(apichat, "Errore cercando di leggere l'RSS! @HAMCHA LEGGI LA CONSOLE!", nil)
		panic(err)
	}
	for broker == nil {
		// Wait for broker
		time.Sleep(time.Second)
	}
	for {
		resp, err := http.Get(mspaRSS)
		if err != nil {
			panicFn(err)
		}
		var out RSS
		err = xml.NewDecoder(resp.Body).Decode(&out)
		if err != nil {
			panicFn(err)
		}
		if len(out.Items) < 1 {
			panicFn(errors.New("0 items in the RSS Feed?"))
		}
		if out.Items[0].Link != lastPage {
			fmt.Println("Got new page: " + out.Items[0].Link)
			if lastPage != "" {
				advert(out.Items[0])
			}
			lastPage = out.Items[0].Link
		}
		time.Sleep(time.Second * time.Duration(delay))
	}
}

func main() {
	brokerAddr := flag.String("broker", "localhost:7314", "Broker address:port")
	delay := flag.Int64("delau", 5*60, "How many seconds between each poll")
	chatID = flag.Int("chatid", -68373985, "Telegram Chat ID to count stats for")
	flag.Parse()
	lastPage = ""

	go startPolling(*delay)

	err := tg.CreateBrokerClient(*brokerAddr, process)
	assert(err)
}