Add broadcast and shutdown commands

Resolves #14.

PROTOCOL.md

@@ -123,6 +123,14 @@ must write some data to the server at least once every 40 seconds.
 - `disconnect`
   - Disconnect from the server.
 
+- `broadcast`
+  - Send a message to all players.
+  - This command is only available to server administrators.
+
+- `shutdown <minutes> <reason>`
+  - Prevent the creation of new matches and periodically warn players about the server shutting down.
+  - This command is only available to server administrators.
+
 ## Server events
 
 All events are sent in either JSON or human-readable format. The structure of

command.go

@@ -29,6 +29,8 @@ const (
 	CommandBoard         = "board"         // Print current board state in human-readable form.
 	CommandPong          = "pong"          // Response to server ping.
 	CommandDisconnect    = "disconnect"    // Disconnect from server.
+	CommandBroadcast     = "broadcast"     // Send a message to all players.
+	CommandShutdown      = "shutdown"      // Prevent the creation of new matches.
 )
 
 type EventType string

pkg/server/client.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"code.rocket9labs.com/tslocum/bgammon"
+	"github.com/leonelquinteros/gotext"
 )
 
 type clientRating struct {
@@ -84,6 +85,10 @@ type serverClient struct {
 	bgammon.Client
 }
 
+func (c *serverClient) Admin() bool {
+	return c.accountID == 1
+}
+
 func (c *serverClient) sendEvent(e interface{}) {
 	// JSON formatted messages.
 	if c.json {
@@ -205,6 +210,12 @@ func (c *serverClient) sendNotice(message string) {
 	})
 }
 
+func (c *serverClient) sendBroadcast(message string) {
+	c.sendEvent(&bgammon.EventNotice{
+		Message: gotext.GetD(c.language, "SERVER BROADCAST:") + " " + message,
+	})
+}
+
 func (c *serverClient) label() string {
 	if len(c.name) > 0 {
 		return string(c.name)

pkg/server/locales/bgammon.pot

@@ -55,6 +55,9 @@ msgstr ""
 msgid "Failed to create match: Please leave the match you are in before creating another."
 msgstr ""
 
+msgid "Failed to create match: The server is shutting down. Reason: %s"
+msgstr ""
+
 msgid "Failed to log in: %s"
 msgstr ""
 
@@ -109,6 +112,9 @@ msgstr ""
 msgid "Please enter an email, username and password."
 msgstr ""
 
+msgid "Please finish your match as soon as possible."
+msgstr ""
+
 msgid "Please leave the match you are in before joining another."
 msgstr ""
 
@@ -121,6 +127,9 @@ msgstr ""
 msgid "Resigned."
 msgstr ""
 
+msgid "SERVER BROADCAST:"
+msgstr ""
+
 msgid "Server error"
 msgstr ""
 
@@ -133,6 +142,15 @@ msgstr ""
 msgid "The match you are in is still in progress."
 msgstr ""
 
+msgid "The server is shutting down. Reason:"
+msgstr ""
+
+msgid "The server is shutting down in 1 minute. Reason:"
+msgstr ""
+
+msgid "The server is shutting down in %d minutes. Reason:"
+msgstr ""
+
 msgid "Unknown command: %s"
 msgstr ""
 

pkg/server/server.go

@@ -86,6 +86,9 @@ type server struct {
 
 	relayChat bool // Chats are not relayed normally. This option is only used by local servers.
 	verbose   bool
+
+	shutdownTime   time.Time
+	shutdownReason string
 }
 
 func NewServer(tz string, dataSource string, mailServer string, passwordSalt string, resetSalt string, relayChat bool, verbose bool, allowDebug bool) *server {
@@ -539,6 +542,44 @@ func (s *server) Analyze(g *bgammon.Game) {
 	os.Exit(0)
 }
 
+func (s *server) handleShutdown() {
+	var mins time.Duration
+	var minutes int
+	t := time.NewTicker(time.Minute)
+	for {
+		mins = time.Until(s.shutdownTime)
+		if mins > 0 {
+			minutes = int(mins.Minutes()) + 1
+		}
+
+		s.clientsLock.Lock()
+		for _, sc := range s.clients {
+			switch minutes {
+			case 0:
+				sc.sendBroadcast(gotext.GetD(sc.language, "The server is shutting down. Reason:"))
+			case 1:
+				sc.sendBroadcast(gotext.GetD(sc.language, "The server is shutting down in 1 minute. Reason:"))
+			default:
+				sc.sendBroadcast(gotext.GetD(sc.language, "The server is shutting down in %d minutes. Reason:", minutes))
+			}
+			sc.sendBroadcast(s.shutdownReason)
+			sc.sendBroadcast(gotext.GetD(sc.language, "Please finish your match as soon as possible."))
+		}
+		s.clientsLock.Unlock()
+
+		<-t.C
+	}
+}
+
+func (s *server) shutdown(delay time.Duration, reason string) {
+	if !s.shutdownTime.IsZero() {
+		return
+	}
+	s.shutdownTime = time.Now().Add(delay)
+	s.shutdownReason = reason
+	go s.handleShutdown()
+}
+
 func RandInt(max int) int {
 	i, err := rand.Int(rand.Reader, big.NewInt(int64(max)))
 	if err != nil {

pkg/server/server_command.go

@@ -245,7 +245,7 @@ COMMANDS:
 		clientGame := s.gameByClient(cmd.client)
 		if clientGame != nil && clientGame.client1 != cmd.client && clientGame.client2 != cmd.client {
 			switch keyword {
-			case bgammon.CommandHelp, "h", bgammon.CommandJSON, bgammon.CommandList, "ls", bgammon.CommandBoard, "b", bgammon.CommandLeave, "l", bgammon.CommandReplay, bgammon.CommandSet, bgammon.CommandDisconnect, bgammon.CommandPong:
+			case bgammon.CommandHelp, "h", bgammon.CommandJSON, bgammon.CommandList, "ls", bgammon.CommandBoard, "b", bgammon.CommandLeave, "l", bgammon.CommandReplay, bgammon.CommandSet, bgammon.CommandPong, bgammon.CommandDisconnect, bgammon.CommandBroadcast, bgammon.CommandShutdown:
 				// These commands are allowed to be used by spectators.
 			default:
 				cmd.client.sendNotice(gotext.GetD(cmd.client.language, "Command ignored: You are spectating this match."))
@@ -320,6 +320,9 @@ COMMANDS:
 			if clientGame != nil {
 				cmd.client.sendNotice(gotext.GetD(cmd.client.language, "Failed to create match: Please leave the match you are in before creating another."))
 				continue
+			} else if !s.shutdownTime.IsZero() {
+				cmd.client.sendNotice(gotext.GetD(cmd.client.language, "Failed to create match: The server is shutting down. Reason: %s", s.shutdownReason))
+				continue
 			}
 
 			sendUsage := func() {
@@ -1232,20 +1235,52 @@ COMMANDS:
 				ev.CasualTabulaMulti = a.casual.tabulaMulti / 100
 			}
 			cmd.client.sendEvent(ev)
+		case bgammon.CommandPong:
+			// Do nothing.
 		case bgammon.CommandDisconnect:
 			if clientGame != nil {
 				clientGame.removeClient(cmd.client)
 			}
 			cmd.client.Terminate("Client disconnected")
-		case bgammon.CommandPong:
-			// Do nothing.
+		case bgammon.CommandBroadcast:
+			if !cmd.client.Admin() {
+				cmd.client.sendNotice("Access denied.")
+				continue
+			} else if len(params) == 0 {
+				cmd.client.sendNotice("Please specify a message to broadcast.")
+				continue
+			}
+
+			message := string(bytes.Join(params, []byte(" ")))
+			s.clientsLock.Lock()
+			for _, sc := range s.clients {
+				sc.sendBroadcast(message)
+			}
+			s.clientsLock.Unlock()
+		case bgammon.CommandShutdown:
+			if !cmd.client.Admin() {
+				cmd.client.sendNotice("Access denied.")
+				continue
+			} else if len(params) < 2 {
+				cmd.client.sendNotice("Please specify the number of minutes until shutdown and the reason.")
+				continue
+			} else if !s.shutdownTime.IsZero() {
+				cmd.client.sendNotice("Server shutdown already in progress.")
+				continue
+			}
+
+			minutes, err := strconv.Atoi(string(params[0]))
+			if err != nil || minutes <= 0 {
+				cmd.client.sendNotice("Error: Invalid shutdown delay.")
+				continue
+			}
+
+			s.shutdown(time.Duration(minutes)*time.Minute, string(bytes.Join(params[1:], []byte(" "))))
 		case "endgame":
 			if !allowDebugCommands {
 				cmd.client.sendNotice(gotext.GetD(cmd.client.language, "You are not allowed to use that command."))
 				continue
-			}
-
-			if clientGame == nil {
+			} else if clientGame == nil {
 				cmd.client.sendNotice(gotext.GetD(cmd.client.language, "You are not currently in a match."))
 				continue
 			}