mchess-server/main.go

package main

import (
	"context"
	"local/m/mchess_server/chess"
	"local/m/mchess_server/usher"
	"log"
	"net/http"
	"os"

	"github.com/gin-gonic/autotls"
	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
	"nhooyr.io/websocket"
)

var cert_path = "/etc/letsencrypt/live/chess.sw-gross.de/"
var cert_file = cert_path + "fullchain.pem"
var key_file = cert_path + "privkey.pem"

func main() {
	hostname, err := os.Hostname()
	if err != nil {
		log.Fatal(err)
	}

	router := gin.Default()

	router.GET("/api/random", registerForRandomGame)
	router.GET("/api/ws", registerWebSocketConnection)

	if hostname == "mbook" {
		log.Println("Starting service WITHOUT TLS")
		log.Fatal(router.Run("localhost:8080"))
	} else {
		log.Fatal(autotls.Run(router, "chess.sw-gross.de"))
	}
}

func registerForRandomGame(c *gin.Context) {

	/*
		What should be done:
		1. Register player
		2. Check if there is a game open that lacks one player
		3. Fill open game, then respond with player id and game id.
		OR

		1. Register player
		2. If there is no open game, open a game and wait for a second player to join
		3. Only after a second player joins, respond with player id and game id.
	*/

	player := chess.NewPlayer(uuid.New())

	usher := usher.GetUsher()
	lobby := usher.WelcomeNewPlayer(player)
	usher.AddPlayerToLobby(player, lobby)

	// Counter point to this approach:
	// Waiting for two players might not be necessary.
	// Just open the lobby and respond with lobby/game id and player id
	// The waiting can be done in the game handler until both players opened a ws connection
	usher.WaitForTwoPlayersInLobby(lobby)

	log.Println("responding with player id ", player.Uuid)

	c.IndentedJSON(http.StatusOK, chess.PlayerInfo{
		PlayerID: player.Uuid,
	})
}

func registerWebSocketConnection(c *gin.Context) {
	webSocketConn, err := websocket.Accept(c.Writer, c.Request, nil)
	if err != nil {
		log.Println(err)
		return
	}
	go waitForAndHandlePlayerID(c, *webSocketConn)
}

func waitForAndHandlePlayerID(ctx context.Context, conn websocket.Conn) {
	msgType, id, err := conn.Read(ctx)

	log.Println("read from websocket: ", msgType, id, err)
	log.Println("id as string", string(id))

	uuid, err := uuid.ParseBytes(id)
	if err != nil {
		log.Println(err)
		conn.Close(websocket.StatusCode(400), err.Error())
		return
	}

	// since we cannot use the lobby anymore (it does not exist anymore after this change) the client needs to
	// send game id and player id so we can make the connection to the player
	//lobby := chess.GetLobby()

	player, found := lobby.GetPlayer(uuid)
	if !found {
		conn.Close(websocket.StatusCode(400), "player not found")
		return
	}
	if player.Conn != nil {
		player.Conn.Close(websocket.StatusCode(400), "closing existing connection")
	}
	player.SetConnection(ctx, conn)
	log.Println("player after setting connection: ", player)
}