package providers

import (
	"encoding/json"
	"errors"
	"fmt"

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

const BEACON_NAME_MATTERMOST = "mattermost"

type OptionsMattermost struct {
	Url     string
	HookId  string
	IconUrl string
	BotName string
	To      []string
}

type mattermost struct {
	opt *OptionsMattermost
}

var _ beaconfire.BeaconFire = &mattermost{}

func NewMattermost(opt *OptionsMattermost) *mattermost {
	return &mattermost{
		opt: opt,
	}
}

func (c mattermost) Name() string {
	return BEACON_NAME_MATTERMOST
}

type message struct {
	Channel  string `json:"channel,omitempty"`
	Username string `json:"username,omitempty"`
	IconUrl  string `json:"icon_url,omitempty"`
	Text     string `json:"text"`
}

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

	u := fmt.Sprintf("%s/hooks/%s", c.opt.Url, c.opt.HookId)

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

		m := message{
			Channel:  channel,
			Username: c.opt.BotName,
			IconUrl:  c.opt.IconUrl,
			Text:     bp.Content,
		}

		msg, err := json.Marshal(m)
		if err != nil {
			return err
		}

		res, err := beaconfire.PostJson(u, msg)
		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 nil != err {
			return err
		}
		if !r.Ok {
			return errors.New(r.Description)
		}
	}
	return nil
}