package commands

import (
	"fmt"
	"io"
	"net/http"
	"regexp"
	"strings"

	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
)

type MolCommand struct{}

func (m MolCommand) Name() string {
	return "mol"
}

func (m MolCommand) Help() string {
	return "2D molecular structure. Example usage: /mol tetraethylgermane"
}

func (m MolCommand) Execute(update tgbotapi.Update, bot *tgbotapi.BotAPI) {
	args := strings.TrimSpace(update.Message.CommandArguments())
	if args == "" {
		msg := tgbotapi.NewMessage(update.Message.Chat.ID, "Input a molecule name dumbass")
		bot.Send(msg)
		return
	}
	cid, err := fetchPubchemCID(args)
	if err != nil {
		msg := tgbotapi.NewMessage(update.Message.Chat.ID, "Structure not found")
		bot.Send(msg)
		return
	}
	imgURL := fmt.Sprintf("https://pubchem.ncbi.nlm.nih.gov/image/imgsrv.fcgi?t=l&cid=%s", cid)
	msg := tgbotapi.NewMessage(update.Message.Chat.ID, imgURL)
	bot.Send(msg)
}

func fetchPubchemCID(compound string) (string, error) {
	url := "https://pubchem.ncbi.nlm.nih.gov/compound/" + compound
	resp, err := http.Get(url)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}
	re := regexp.MustCompile(`<meta name="pubchem_uid_value" content="(\d+)"/?>`)
	matches := re.FindStringSubmatch(string(body))
	if len(matches) < 2 {
		return "", fmt.Errorf("CID not found")
	}
	return matches[1], nil
}

func init() {
	Register(MolCommand{})
}