package main

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

	"github.com/gorilla/websocket"
)

const (
	MSG_TYPE_AUTH   string = "auth"
	MSG_TYPE_SET_ID string = "set-id"
)

type AuthRequestClient struct {
	conn *websocket.Conn
}

type AuthRequestProtocolMessage struct {
	MessageType string `json:"type"`
	Parameters  map[string]string
}

func (c *AuthRequestClient) ReceiveRequest() (*AuthRequest, error) {
	message, err := c.receiveProtocolMessage()

	if err != nil {
		return nil, err
	}

	if message.MessageType != MSG_TYPE_AUTH {
		return nil, errors.New(
			fmt.Sprintf(
				"Wrong protocol message type, expected message of type \"%s\", got \"%s\"",
				MSG_TYPE_AUTH,
				message.MessageType,
			),
		)
	}

	instance, ok := message.Parameters["instance"]

	if !ok {
		return nil, errors.New("No \"instance\" parameter included in auth request parameters")
	}

	r := &AuthRequest{
		Client:   c,
		Instance: instance,
	}

	return r, nil
}

func (c *AuthRequestClient) receiveProtocolMessage() (*AuthRequestProtocolMessage, error) {
	_, message, err := c.conn.ReadMessage()

	if err != nil {
		return nil, err
	}

	var protocolMessage *AuthRequestProtocolMessage

	err = json.Unmarshal(message, protocolMessage)

	if err != nil {
		return nil, err
	}

	return protocolMessage, nil
}

func (c *AuthRequestClient) PropagateID(ID string) error {
	message := &AuthRequestProtocolMessage{
		MessageType: MSG_TYPE_SET_ID,
		Parameters: map[string]string{
			"id": ID,
		},
	}

	err := c.conn.WriteJSON(message)

	return err
}