package matrix

import (
	"encoding/json"

	"github.com/h2non/gentleman/plugins/body"
	"gopkg.in/h2non/gentleman.v2"
	"gopkg.in/h2non/gentleman.v2/plugins/query"
)

// Login logs in to the homeserver and returns an Authinfo struct containing
// information such as the UserID, the HomeServer of the entity that was logged
// and most important: the AccessToken for further verification
func Login(username, password, homeserver string) (Authinfo, error) {
	cli := gentleman.New()
	cli.URL(homeserver)

	req := cli.Request()
	req.Path("/_matrix/client/r0/login")
	req.Method("POST")

	data := map[string]string{
		"type":     "m.login.password",
		"user":     username,
		"password": password,
	}
	req.Use(body.JSON(data))

	res, err := req.Send()
	if err != nil {
		return Authinfo{}, err
	}
	if !res.Ok {
		return Authinfo{}, err
	}

	var authinfo Authinfo
	if err := json.Unmarshal(res.Bytes(), &authinfo); err != nil {
		return Authinfo{}, err
	}
	return authinfo, nil
}

func Sync(authinfo Authinfo) {
	cli := gentleman.New()
	cli.URL(authinfo.HomeServer)

	req := cli.Request()
	req.Path("/_matrix/client/r0/sync")
	req.Method("GET")

    req.Use(query.Set("access_token", authinfo.AccessToken))

	res, err := req.Send()
	if err != nil {
		return err
	}
	if !res.Ok {
		return err
	}

	var authinfo Authinfo
	if err := json.Unmarshal(res.Bytes(), &authinfo); err != nil {
		return Authinfo{}, err
	}
	return authinfo, nil
}

// Authinfo defines the fields returned after logging in
type Authinfo struct {
	UserID      string `json:"user_id"`
	HomeServer  string `json:"home_server"`
	DeviceID    string `json:"device_id"`
	AccessToken string `json:"access_token"`
}