From c3db42daee79d44ac4693a2209ca95bc5b0dbb93 Mon Sep 17 00:00:00 2001
From: Trevor Slocum <trevor@rocket9labs.com>
Date: Wed, 15 Nov 2023 14:41:56 -0800
Subject: [PATCH] Send game state to both players from the perspective of
 player 1 (black)

---
 PROTOCOL.md                  |  2 ++
 cmd/bgammon-server/game.go   | 36 +++++++++++++++++++++++++++++++++---
 cmd/bgammon-server/server.go | 15 +++++++++------
 3 files changed, 44 insertions(+), 9 deletions(-)

diff --git a/PROTOCOL.md b/PROTOCOL.md
index 4e94313..909d3bf 100644
--- a/PROTOCOL.md
+++ b/PROTOCOL.md
@@ -6,6 +6,8 @@ Replace spaces with underscores when sending a password to the server.
 
 When connected via TCP, commands and events are separated by newlines.
 
+Players always perceive games from the perspective of player number 1 (black).
+
 ## User commands
 
 ### Format
diff --git a/cmd/bgammon-server/game.go b/cmd/bgammon-server/game.go
index c899881..d5484cd 100644
--- a/cmd/bgammon-server/game.go
+++ b/cmd/bgammon-server/game.go
@@ -84,12 +84,42 @@ func (g *serverGame) sendBoard(client *serverClient) {
 		if client.playerNumber == 2 {
 			ev.GameState.Game = ev.GameState.Copy()
 
+			ev.GameState.PlayerNumber = 1
+			ev.GameState.Player1, ev.GameState.Player2 = ev.GameState.Player2, ev.GameState.Player1
+			ev.GameState.Player1.Number = 1
+			ev.GameState.Player2.Number = 2
+
+			switch ev.GameState.Turn {
+			case 1:
+				ev.GameState.Turn = 2
+			case 2:
+				ev.GameState.Turn = 1
+			}
+
+			switch ev.GameState.DoublePlayer {
+			case 1:
+				ev.GameState.DoublePlayer = 2
+			case 2:
+				ev.GameState.DoublePlayer = 1
+			}
+
+			switch ev.GameState.Winner {
+			case 1:
+				ev.GameState.Winner = 2
+			case 2:
+				ev.GameState.Winner = 1
+			}
+
+			if ev.GameState.Roll1 == 0 || ev.GameState.Roll2 == 0 {
+				ev.GameState.Roll1, ev.GameState.Roll2 = ev.GameState.Roll2, ev.GameState.Roll1
+			}
+
 			// Flip board.
 			for space := 1; space <= 24; space++ {
-				ev.Board[space] = g.Game.Board[bgammon.FlipSpace(space, client.playerNumber)]
+				ev.Board[space] = g.Game.Board[bgammon.FlipSpace(space, client.playerNumber)] * -1
 			}
-			ev.Board[bgammon.SpaceHomePlayer], ev.Board[bgammon.SpaceHomeOpponent] = ev.Board[bgammon.SpaceHomeOpponent], ev.Board[bgammon.SpaceHomePlayer]
-			ev.Board[bgammon.SpaceBarPlayer], ev.Board[bgammon.SpaceBarOpponent] = ev.Board[bgammon.SpaceBarOpponent], ev.Board[bgammon.SpaceBarPlayer]
+			ev.Board[bgammon.SpaceHomePlayer], ev.Board[bgammon.SpaceHomeOpponent] = ev.Board[bgammon.SpaceHomeOpponent]*-1, ev.Board[bgammon.SpaceHomePlayer]*-1
+			ev.Board[bgammon.SpaceBarPlayer], ev.Board[bgammon.SpaceBarOpponent] = ev.Board[bgammon.SpaceBarOpponent]*-1, ev.Board[bgammon.SpaceBarPlayer]*-1
 
 			ev.Moves = bgammon.FlipMoves(g.Game.Moves, client.playerNumber)
 
diff --git a/cmd/bgammon-server/server.go b/cmd/bgammon-server/server.go
index 11a8a38..ba9c750 100644
--- a/cmd/bgammon-server/server.go
+++ b/cmd/bgammon-server/server.go
@@ -772,11 +772,6 @@ COMMANDS:
 				continue
 			}
 
-			ev := &bgammon.EventRolled{
-				Roll1: clientGame.Roll1,
-				Roll2: clientGame.Roll2,
-			}
-			ev.Player = string(cmd.client.name)
 			if clientGame.Turn == 0 && clientGame.Roll1 != 0 && clientGame.Roll2 != 0 {
 				if clientGame.Roll1 > clientGame.Roll2 {
 					clientGame.Turn = 1
@@ -788,6 +783,14 @@ COMMANDS:
 				}
 			}
 			clientGame.eachClient(func(client *serverClient) {
+				ev := &bgammon.EventRolled{
+					Roll1: clientGame.Roll1,
+					Roll2: clientGame.Roll2,
+				}
+				ev.Player = string(cmd.client.name)
+				if client.playerNumber == 2 {
+					ev.Roll1, ev.Roll2 = ev.Roll2, ev.Roll1
+				}
 				client.sendEvent(ev)
 				if clientGame.Turn != 0 || !client.json {
 					clientGame.sendBoard(client)
@@ -1052,7 +1055,7 @@ COMMANDS:
 
 				ev2 := &bgammon.EventJoined{
 					GameID:       newGame.id,
-					PlayerNumber: 2,
+					PlayerNumber: 1,
 				}
 				ev2.Player = newGame.Player2.Name