include shell counts in game dto

game/game.go

@@ -226,6 +226,11 @@ func (g *Match) Concede(id player.ID) error {
 
 // DTO returns the current match state as viewed by the given player.
 func (g *Match) DTO(id player.ID) serve.Game {
+	var live, blank int
+	if g.turn == 1 {
+		live = len(g.shells) / 2
+		blank = len(g.shells) - live
+	}
 	return serve.Game{
 		Players: [2]serve.Player{
 			g.players[0].DTO(),
@@ -235,22 +240,11 @@ func (g *Match) DTO(id player.ID) serve.Game {
 		Damage:   g.damage,
 		Shell:    g.Peek(id),
 		Previous: g.prev,
+		Live:     live,
+		Blank:    blank,
 	}
 }
 
-// ShellCounts returns the number of live and blank shells.
-func (g *Match) ShellCounts() serve.ShellCounts {
-	var counts serve.ShellCounts
-	for _, s := range g.shells {
-		if s {
-			counts.Live++
-		} else {
-			counts.Blank++
-		}
-	}
-	return counts
-}
-
 var (
 	ErrWrongTurn  = errors.New("not your turn")
 	ErrGameEnded  = errors.New("the shotgun is empty")

game/game_test.go

@@ -79,7 +79,6 @@ func TestGameStartGroup(t *testing.T) {
 	t.Parallel()
 	g := New(player.ID{1}, player.ID{2})
 	for i := uint(1); i < 10000; i++ {
-		counts := g.ShellCounts()
 		checks := []struct {
 			failed bool
 			msg    string
@@ -89,7 +88,6 @@ func TestGameStartGroup(t *testing.T) {
 			{g.players[1].items[0] == ItemNone, "challenger has no first item: %v", []any{g.players[1].items}},
 			{len(g.shells) < 2 || len(g.shells) > 8, "bad shells count %d, want 2-8", []any{len(g.shells)}},
 			{&g.shells[0] != &g.shellArray[0], "shells[0] is %p, want %p", []any{&g.shells[0], &g.shellArray[0]}},
-			{counts.Live != counts.Blank && counts.Live+1 != counts.Blank, "imbalanced live/blank %d/%d", []any{counts.Live, counts.Blank}},
 			{g.round != 1, "round is %d, want 1", []any{g.round}},
 			{g.turn != 1, "turn is %d, want 1", []any{g.turn}},
 			{g.damage != 1, "damage is %d, want 1", []any{g.damage}},
@@ -436,53 +434,56 @@ func TestConcede(t *testing.T) {
 	}
 }
 
-func TestGameShellCounts(t *testing.T) {
+func TestGameDTO(t *testing.T) {
-	cases := []struct {
-		name   string
-		shells []bool
-		want   serve.ShellCounts
-	}{
-		{
-			name:   "empty",
-			shells: nil,
-			want:   serve.ShellCounts{Live: 0, Blank: 0},
-		},
-		{
-			name:   "one-live",
-			shells: []bool{true},
-			want:   serve.ShellCounts{Live: 1, Blank: 0},
-		},
-		{
-			name:   "one-blank",
-			shells: []bool{false},
-			want:   serve.ShellCounts{Live: 0, Blank: 1},
-		},
-		{
-			name:   "two",
-			shells: []bool{true, false},
-			want:   serve.ShellCounts{Live: 1, Blank: 1},
-		},
-		{
-			name:   "three",
-			shells: []bool{true, false, true},
-			want:   serve.ShellCounts{Live: 2, Blank: 1},
-		},
-		{
-			name:   "four",
-			shells: []bool{true, false, true, false},
-			want:   serve.ShellCounts{Live: 2, Blank: 2},
-		},
-	}
-	for _, c := range cases {
-		c := c
-		t.Run(c.name, func(t *testing.T) {
 	t.Parallel()
-			g := New(player.ID{1}, player.ID{2})
+	dealer, chall := player.ID{1}, player.ID{2}
-			g.shells = c.shells
+	g := New(dealer, chall)
-			if got := g.ShellCounts(); got != c.want {
+	{
-				t.Errorf("wrong shell counts: got %#v, wanted %#v", got, c.want)
+		want := serve.Game{
+			Players: [2]serve.Player{
+				g.players[0].DTO(),
+				g.players[1].DTO(),
+			},
+			Round:    g.round,
+			Damage:   g.damage,
+			Shell:    nil,
+			Previous: nil,
+			Live:     len(g.shells) / 2,
+			Blank:    (len(g.shells) + 1) / 2,
+		}
+		if got := g.DTO(dealer); want != got {
+			t.Errorf("dealer sees the wrong thing:\nwant %+v\ngot  %+v", want, got)
+		}
+		if got := g.DTO(chall); want != got {
+			t.Errorf("challenger sees the wrong thing:\nwant %+v\ngot  %+v", want, got)
+		}
+		if got := g.DTO(player.ID{}); want != got {
+			t.Errorf("observer sees the wrong thing:\nwant %+v\ngot  %+v", want, got)
+		}
+	}
+	g.Shoot(chall, false)
+	{
+		want := serve.Game{
+			Players: [2]serve.Player{
+				g.players[0].DTO(),
+				g.players[1].DTO(),
+			},
+			Round:    g.round,
+			Damage:   g.damage,
+			Shell:    nil,
+			Previous: &g.shellArray[0],
+			Live:     0,
+			Blank:    0,
+		}
+		if got := g.DTO(dealer); want != got {
+			t.Errorf("dealer sees the wrong thing:\nwant %+v\ngot  %+v", want, got)
+		}
+		if got := g.DTO(chall); want != got {
+			t.Errorf("challenger sees the wrong thing:\nwant %+v\ngot  %+v", want, got)
+		}
+		if got := g.DTO(player.ID{}); want != got {
+			t.Errorf("observer sees the wrong thing:\nwant %+v\ngot  %+v", want, got)
 		}
-		})
 	}
 }
 

serve/dto.go

@@ -17,6 +17,12 @@ type Game struct {
 	Shell *bool `json:"shell,omitempty"`
 	// Previous gives whether the previously discharged shell was live.
 	Previous *bool `json:"previous"`
+	// Live is the number of live shells this round, if it is the first turn
+	// of the round.
+	Live int `json:"live,omitempty"`
+	// Blank is the number of blank shells this round, if it is the first turn
+	// of the round.
+	Blank int `json:"blank,omitempty"`
 }
 
 // Player is the JSON DTO for a player.
@@ -37,9 +43,3 @@ type GameStart struct {
 	ID     GameID `json:"id"`
 	Dealer bool   `json:"dealer"`
 }
-
-// ShellCounts is the JSON DTO for shell counts emitted at the start of a shell group.
-type ShellCounts struct {
-	Live  int `json:"live"`
-	Blank int `json:"blank"`
-}