package notify

import (
	"fmt"
	"log"

	"github.com/slack-go/slack"
)

const slackHookBaseURL = "hooks.slack.com/services"

//Notifier interface represent mean to send notification
type Notifier interface {
	Notify(message string)
}

//Message store and represent alerting message
type Message struct {
	ShouldNotify bool
	Content      string
}

type SlackNotifier struct {
	BotID         string
	DestChannelID string
	WebhookID     string
}

//NewSlackNotifier create slack notifier
func NewSlackNotifier(BotID, DestChannelID, WebhookID string) *SlackNotifier {
	return &SlackNotifier{
		BotID:         BotID,
		DestChannelID: DestChannelID,
		WebhookID:     WebhookID,
	}
}

//Notify send notification to channel
func (sn *SlackNotifier) Notify(message Message) {
	if message.ShouldNotify {
		msg := &slack.WebhookMessage{
			Text: message.Content,
		}

		url := fmt.Sprintf("https://%s/%s/%s/%s", slackHookBaseURL, sn.BotID, sn.DestChannelID, sn.WebhookID)
		err := slack.PostWebhook(url, msg)
		if err != nil {
			log.Printf("Send message error %+v", err)
		}
	}
}