package providers

import (
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"net/url"

	"git.wenlab.co/joe/beaconfire"
)

const (
	_TELEGRAM_DEF_PARSE_MODE = "HTML"

	BEACON_NAME_TELEGRAM = "telegram"
)

type OptionsTelegram struct {
	Token string
	To    []string // userId
	// Channel []string
	// ParseMode string
}

type telegram struct {
	opt *OptionsTelegram
}

var _ beaconfire.BeaconFire = &telegram{}

func NewTelegram(opt *OptionsTelegram) *telegram {
	return &telegram{
		opt: opt,
	}
}

func (c *telegram) Name() string {
	return BEACON_NAME_TELEGRAM
}

func (c *telegram) Send(bp *beaconfire.BeaconMessage) error {
	if len(c.opt.To) <= 0 {
		return beaconfire.ErrNoReceiver
	}

	u := fmt.Sprintf("https://api.telegram.org/bot%s/sendMessage", c.opt.Token)

	v := url.Values{}
	content := bp.FormatHTML()
	v.Set("parse_mode", _TELEGRAM_DEF_PARSE_MODE)
	v.Set("text", content)

	for _, channel := range c.opt.To {

		v.Set("chat_id", channel)

		res, err := beaconfire.Request(http.MethodPost, u, []byte(v.Encode()), map[string]string{
			"Content-Type": "application/x-www-form-urlencoded",
		}, "", "")
		if err != nil {
			return err
		}

		var r struct {
			Ok          bool   `json:"ok"`
			ErrorCode   int    `json:"error_code"`
			Description string `json:"description"`
		}
		err = json.Unmarshal(res, &r)
		if err != nil {
			return err
		}
		if !r.Ok {
			return errors.New(r.Description)
		}
	}
	return nil
}