stappabot/main.go

package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"os"
	"strconv"
	"strings"

	"github.com/hamcha/tg"
)

type Config struct {
	Token                 string
	Bind                  string
	WebhookURL            string
	WebhookPath           string
	MaxRequestsPerMessage int
}

func checkErr(err error, msg string, args ...interface{}) {
	if err != nil {
		fmt.Printf("FATAL ERROR\n"+msg+":\n  ", args...)
		fmt.Println(err.Error())
		os.Exit(1)
	}
}

var api *tg.Telegram
var cfg Config

func main() {
	cfgpath := flag.String("config", "stappa.conf", "Path to config file")
	flag.Parse()

	cfgfile, err := os.Open(*cfgpath)
	checkErr(err, "Could not open config file")

	err = json.NewDecoder(cfgfile).Decode(&cfg)
	checkErr(err, "Could not decode JSON from config file contents")

	cfgfile.Close()

	// Set default maxreq
	if cfg.MaxRequestsPerMessage < 1 {
		cfg.MaxRequestsPerMessage = 5
	}

	api = tg.MakeAPIClient(cfg.Token)
	api.SetWebhook(cfg.WebhookURL)
	api.HandleWebhook(cfg.Bind, cfg.WebhookPath, webhook)
}

func webhook(update tg.APIUpdate) {
	// Handle inline queries (99% of the usage I hope)
	if update.Inline != nil {
		query := update.Inline.Query
		offset, _ := strconv.Atoi(update.Inline.Offset)
		results, err := scryfallSearch(query, offset)
		if err != nil {
			fmt.Println(err)
			// DO SOMETHING
			return
		}

		nextcard := ""
		if results.HasMore {
			nextcard = strconv.Itoa(offset + len(results.Data))
		}
		photos := make([]tg.APIInlineQueryResultPhoto, len(results.Data))
		for i, card := range results.Data {
			caption := fmt.Sprintf("EDHREC rank: #%d - cardmarket: € %s", card.EdhrecRank, card.Eur)
			photos[i] = tg.APIInlineQueryResultPhoto{
				Type:     "photo",
				ResultID: card.ID,
				PhotoURL: card.ImageUris.Large,
				ThumbURL: card.ImageUris.Normal,
				Title:    card.Name,
				Caption:  caption,
				Width:    672,
				Height:   936,
				ReplyMarkup: &tg.APIInlineKeyboardMarkup{
					InlineKeyboard: [][]tg.APIInlineKeyboardButton{{
						{
							Text: "Scryfall",
							URL:  card.ScryfallURI,
						}, {
							Text: "EDHREC",
							URL:  card.RelatedUris.Edhrec,
						}, {
							Text: "MCM",
							URL:  card.PurchaseUris.Magiccardmarket,
						},
					}},
				},
			}
		}

		err = api.AnswerInlineQuery(tg.InlineQueryResponse{
			QueryID:    update.Inline.QueryID,
			Results:    photos,
			NextOffset: nextcard,
		})
		if err != nil {
			fmt.Println(err)
			// DO SOMETHING
			return
		}
	}

	// Check for card requests
	if update.Message != nil && update.Message.Text != nil {
		requests := getCardRequests(*update.Message.Text)
		if len(requests) > cfg.MaxRequestsPerMessage {
			api.SendTextMessage(tg.ClientTextMessageData{
				ChatID:  update.Message.Chat.ChatID,
				Text:    fmt.Sprintf("You asked for way too many cards (%d!), please only ask me for at most %d cards in a single message.", len(requests), cfg.MaxRequestsPerMessage),
				ReplyID: &update.Message.MessageID,
			})
			return
		}
		cardmedia := []tg.APIInputMediaPhoto{}
		errlist := []string{}
		for _, cardname := range requests {
			card, err := scryfallGetCard(cardname)
			if err != nil {
				errlist = append(errlist, cardname)
			} else {
				cardmedia = append(cardmedia, tg.APIInputMediaPhoto{
					Type:  "photo",
					Media: card.ImageUris.Large,
				})
			}
		}
		if len(cardmedia) > 0 {
			api.SendAlbum(tg.ClientAlbumData{
				ChatID:  update.Message.Chat.ChatID,
				Media:   cardmedia,
				Silent:  true,
				ReplyID: &update.Message.MessageID,
			})
		}
		if len(errlist) > 0 {
			api.SendTextMessage(tg.ClientTextMessageData{
				ChatID:  update.Message.Chat.ChatID,
				Text:    "I couldn't find these cards you mentioned: " + strings.Join(errlist, ", "),
				ReplyID: &update.Message.MessageID,
			})
		}
	}
}

func getCardRequests(str string) (out []string) {
	remaining := str
	for len(remaining) > 1 {
		nextToken := strings.Index(remaining, "[[")
		if nextToken < 0 {
			break
		}
		endToken := strings.Index(remaining[nextToken:], "]]")
		if endToken < 0 {
			break
		}
		out = append(out, remaining[nextToken+2:nextToken+endToken])
		remaining = remaining[nextToken+2+endToken:]
	}
	return
}