lobby IS a game

src/state/fsm/lobby/internal/event.go

@@ -0,0 +1,63 @@
+package lobby
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+type Event interface {
+	LobbyEvent()
+}
+
+type PlayerJoin struct {
+	ID int
+}
+
+func (PlayerJoin) LobbyEvent() {}
+
+type PlayerLeave struct {
+	ID int
+}
+
+func (PlayerLeave) LobbyEvent() {}
+
+func ParseEvent(b []byte) (Event, error) {
+	var wrapper struct {
+		Type    string          `json:"type"`
+		Package string          `json:"package"`
+		Payload json.RawMessage `json:"payload"`
+	}
+	if err := json.Unmarshal(b, &wrapper); err != nil {
+		return nil, err
+	} else if wrapper.Package != "lobby" {
+		return nil, nil
+	}
+
+	var e Event
+	var err error
+	switch wrapper.Type {
+	case "lobby.PlayerJoin":
+		v := PlayerJoin{}
+		err = json.Unmarshal(wrapper.Payload, &v)
+		e = v
+	case "lobby.PlayerLeave":
+		v := PlayerLeave{}
+		err = json.Unmarshal(wrapper.Payload, &v)
+		e = v
+	default:
+		return nil, fmt.Errorf("failed to parse event %q", wrapper.Type)
+	}
+	return e, err
+}
+
+func MarshalEvent(e Event) ([]byte, error) {
+	var marshalme struct {
+		Payload Event  `json:"payload"`
+		Type    string `json:"type"`
+		Package string `json:"package"`
+	}
+	marshalme.Payload = e
+	marshalme.Type = fmt.Sprintf("%T", e)
+	marshalme.Package = "lobby"
+	return json.Marshal(marshalme)
+}

src/state/fsm/lobby/internal/event_test.go

@@ -0,0 +1,36 @@
+package lobby_test
+
+import (
+	lobby "gitea/price-is-wrong/src/state/fsm/lobby/internal"
+	"testing"
+)
+
+func TestMarshalUnmarshal(t *testing.T) {
+	cases := map[string]struct {
+		e lobby.Event
+	}{
+		"PlayerJoin":  {e: lobby.PlayerJoin{ID: 1}},
+		"PlayerLeave": {e: lobby.PlayerLeave{ID: 1}},
+	}
+
+	for name, d := range cases {
+		c := d
+		t.Run(name, func(t *testing.T) {
+			b, err := lobby.MarshalEvent(c.e)
+			if err != nil {
+				t.Fatal(err)
+			}
+			t.Logf("marshalled: %s", b)
+
+			e, err := lobby.ParseEvent(b)
+			if err != nil {
+				t.Fatal(err)
+			}
+			t.Logf("unmarshalled: %+v", e)
+
+			if c.e != e {
+				t.Errorf("expected %+v but got %+v", c.e, e)
+			}
+		})
+	}
+}

src/state/fsm/lobby/internal/lobby.go

@@ -0,0 +1,11 @@
+package lobby
+
+import "context"
+
+type Lobby interface{}
+
+type lobby struct{}
+
+func NewLobby(ctx context.Context) (Lobby, error) {
+	return lobby{}, nil
+}

src/state/fsm/lobby/internal/storage.go

@@ -0,0 +1,24 @@
+package lobby
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"gitea/price-is-wrong/src/lib"
+)
+
+type Storage interface {
+}
+
+type DB struct{ db *sql.DB }
+
+var _ Storage = DB{}
+
+func NewDB(ctx context.Context) (DB, error) {
+	db := lib.ExtractDB(ctx)
+	if db == nil {
+		return DB{}, fmt.Errorf("db in context expected")
+	}
+
+	return DB{db: db}, nil
+}

src/state/fsm/lobby/internal/storage_test.go

@@ -0,0 +1,15 @@
+package lobby_test
+
+import (
+	"gitea/price-is-wrong/src/lib"
+	lobby "gitea/price-is-wrong/src/state/fsm/lobby/internal"
+	"testing"
+)
+
+func TestDB(t *testing.T) {
+	db, err := lobby.NewDB(lib.NewTestCtx(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	_ = db
+}