385 lines
9.8 KiB

package server
import (
v ""
// GameID is essentially the name of the game we want to join
type GameID struct {
Id string `json:"id"`
// PlayerID is the internal hash we give to a client
type PlayerID struct {
Type string `json:"type"`
Hash string `json:"id"`
func NewPlayerID(id string) *PlayerID {
return &PlayerID{
Type: "idreq",
Hash: id,
// ClientID is how a player wants to be known
type ClientID struct {
Type string `json:"type"`
Name string `json:"name"`
Useragent string `json:"useragent"`
// ClientID.Valid is used to be sure the player connecting is of appropriate
// type.
func (c *ClientID) Valid() (bool, string) {
switch c.Type {
case "robot", "spectator":
return true, ""
return false, "useragent must be 'robot' or 'spectator'"
// ClientConfig embodies a map of stats requests
type ClientConfig struct {
ID string `json:"id"`
Stats map[string]StatsRequest `json:"stats"`
// ClientConfig.Valid is what determins if a player has asked for too many
// points.
func (config ClientConfig) Valid(max int) bool {
total := 0
for _, s := range config.Stats {
total += (s.Speed +
s.Hp +
s.WeaponRadius +
s.ScannerRadius +
s.Acceleration +
s.TurnSpeed +
s.FireRate +
s.WeaponDamage +
if total > max {
return false
return true
// BoardSize is the response containing the geometry of the requested game.
type BoardSize struct {
Width float64 `json:"width"`
Height float64 `json:"height"`
// GameParam is sent to the client to tell them of the geometry of the game
// requested, how many points they may use, and what encoding the server will
// use to communicate with the client.
type GameParam struct {
// TODO: should have information about max points in here
BoardSize BoardSize `json:"boardsize"`
MaxPoints int `json:"max_points"`
Encoding string `json:"encoding"`
Type string `json:"type"`
// Handshake is simply the response to a client to let them know if the number
// of stats they've asked for is reasonable. If false it means try again.
type Handshake struct {
ID string `json:"id"`
Success bool `json:"success"`
Type string `json:"type"`
func NewHandshake(id string, success bool) *Handshake {
return &Handshake{
ID: id,
Success: success,
Type: "handshake",
// Message is an empty interface used to send out arbitrary JSON/gob to
// clients, both players/spectators. We might send out Boardstate or GameOver,
// hence the interface{}.
type Message interface{}
// Boardstate is the main struct calculated every tick (per player) and sent
// out to clients. It contains the appropriate subset of all data needed by
// each player/spectator.
type Boardstate struct {
MyRobots []Robot `json:"my_robots"`
OtherRobots []OtherRobot `json:"robots"`
Projectiles []Projectile `json:"projectiles"`
Splosions []Splosion `json:"splosions"`
Obstacles []Obstacle `json:"objects"`
Type string `json:"type"`
Turn int `json:"turn"`
AllBots []BotHealth `json:"all_bots"`
Messages []string `json:"messages"`
func NewBoardstate() *Boardstate {
return &Boardstate{
MyRobots: []Robot{},
OtherRobots: []OtherRobot{},
Projectiles: []Projectile{},
Splosions: []Splosion{},
AllBots: []BotHealth{},
Type: "boardstate",
// Special outbound message with a []string of winners.
type GameOver struct {
Winners []string `json:"winners"`
Type string `json:"type"`
func NewGameOver() *GameOver {
return &GameOver{
Type: "gameover",
Winners: make([]string, 0),
// Failure is a simple stuct that is typically converted to JSON and sent out
// to the clients so they can know why something has failed.
type Failure struct {
Reason string `json:"reason"`
Type string `json:"type"`
func NewFailure(reason string) *Failure {
return &Failure{
Reason: reason,
Type: "failure",
// Controller.AddPlayer is the HTTP -> websocket route that is used to
// negociate a connection with a player/spectator.
func (c *Controller) AddPlayer(ws *websocket.Conn) {
var gid GameID
err := websocket.JSON.Receive(ws, &gid)
if err != nil {
log.Println("problem parsing the requested game id")
game := c.Games.Get(gid.Id)
if game == nil {
var err error
game, err = NewGame(
game.defaultObstacles = c.Conf.Obstacles
game.obstacleCount = c.Conf.ObstacleCount
log.Printf("%t", len(game.defaultObstacles) == 0)
if len(game.defaultObstacles) == 0 {
game.obstacles = GenerateObstacles(
} else {
game.obstacles = c.Conf.Obstacles
if err != nil {
log.Printf("problem creating game: %s", gid.Id)
websocket.JSON.Send(ws, NewFailure("game creation error"))
player_id := c.Idg.Hash()
err = websocket.JSON.Send(ws, NewPlayerID(player_id))
if err != nil {
log.Printf("game %s: unable to send player_id to player %s", gid.Id, player_id)
websocket.JSON.Send(ws, NewFailure("send error"))
} else {
log.Printf("game %s: sent player id: %s", gid.Id, player_id)
var clientid ClientID
err = websocket.JSON.Receive(ws, &clientid)
if err != nil {
log.Printf("unable to parse ClientID: gid: %s, player: %s", gid.Id, player_id)
websocket.JSON.Send(ws, NewFailure("parse error"))
} else {
log.Printf("game %s: recieved: %+v", gid.Id, clientid)
if v, msg := clientid.Valid(); !v {
log.Printf("clientid is invalid: %+v", clientid)
reqEncs := []string{}
err = websocket.JSON.Receive(ws, &reqEncs)
if err != nil {
log.Printf("%s %s unable to parse requested encodings", gid.Id, player_id)
websocket.JSON.Send(ws, NewFailure("encoding recieve error"))
prefEncs := []string{
var encoding string
for _, prefEnc := range prefEncs {
for _, reqEnc := range reqEncs {
if reqEnc == prefEnc {
encoding = prefEnc
log.Println("selected following encoding:", encoding)
break encodingLoops
if encoding == "" {
log.Printf("%s %s unable to negociate encoding", gid.Id, player_id)
NewFailure("no overlap on supported encodings; I suggest using json"),
gameParam := game.gameParam()
gp := struct {
Encoding string `json:"encoding"`
GameParam: *gameParam,
Encoding: encoding,
err = websocket.JSON.Send(ws, gp)
if err != nil {
log.Printf("%s %s game param send error", gid.Id, player_id)
websocket.JSON.Send(ws, NewFailure("game param send error"))
} else {
log.Printf("%s -> %s: sent %+v", gid.Id, player_id, gameParam)
switch clientid.Type {
case "robot":
var conf ClientConfig
for {
log.Printf("%s Waiting for client to send conf ...", player_id)
err = websocket.JSON.Receive(ws, &conf)
log.Printf("%s: conf received: %s", player_id, conf.ID)
if err != nil {
log.Printf("%s %s config parse error", gid.Id, player_id)
websocket.JSON.Send(ws, NewFailure("config parse error"))
// TODO: verify conf's type
if conf.Valid(game.maxPoints) {
log.Printf("%s -> %s: valid client config", gid.Id, player_id)
_ = websocket.JSON.Send(ws, NewHandshake(player_id, true))
} else {
log.Printf("%s: Config is INVALID, abort", player_id)
_ = websocket.JSON.Send(ws, NewFailure("invalid config"))
p := NewPlayer(player_id, ws,, encoding)
log.Printf("%s: made a player: %s", gid.Id, p.Id)
convertedStats := map[string]Stats{}
for name, stats := range conf.Stats {
dstat := DeriveStats(stats)
r := Robot{
Stats: dstat,
Id: c.Idg.Hash(),
Name: name,
Health: 10,
Heading: v.Vector2d{X: 1, Y: 0},
Scanners: make([]Scanner, 0),
Delta: c.Conf.Delta,
idg: c.Idg,
r.Health = r.Stats.Hp
log.Printf("%s: adding robot: %s", p.Id, r.Id)
p.Robots = append(p.Robots, &r)
dstat.Id = r.Id
convertedStats[name] = dstat
statsPayload := struct {
Stats map[string]Stats `json:"stats"`
Type string `json:"type"`
Stats: convertedStats,
Type: "stats",
err = websocket.JSON.Send(ws, &statsPayload)
if err != nil {
log.Printf("error sending convertedStats to client: %s", err)
websocket.JSON.Send(ws, NewFailure("protocol error: convertedStats"))
} else {
log.Printf("%s -> %s: sent stats payload", gid.Id, p.Id)
log.Printf("%s, %s: about to register this player", gid.Id, p.Id)
game.register <- p
log.Printf("%s, %s: registered player", gid.Id, p.Id)
defer func() {
log.Printf("%s, %s: about to unregister this player", gid.Id, p.Id)
game.unregister <- p
log.Printf("%s, %s: unregistered player", gid.Id, p.Id)
go p.Sender()
log.Printf("%s -> %s: p.sender went", gid.Id, p.Id)
"%s (player): %v (robot) has been disconnected from %s (game)",
case "spectator":
s := NewSpectator(player_id, ws,, encoding)
log.Printf("%s, %s: about to register this spectator", gid.Id, s.Id)
game.sregister <- s
log.Printf("%s, %s: registered spectator", gid.Id, s.Id)
defer func() {
log.Printf("%s, %s: about to unregister this spectator", gid.Id, s.Id)
game.sunregister <- s
log.Printf("%s, %s: unregistered spectator", gid.Id, s.Id)
go s.Sender()
log.Printf("%s -> %s: s.sender went", gid.Id, s.Id)
log.Printf("game %s: spectator %+v has been disconnected from this game", gid.Id, s)
log.Printf("exiting AddPlayer")