refactor: rename game package to connect4, drop Game prefix from types

Rename game/ -> connect4/ to avoid c4/game stutter. Drop redundant
Game prefix from exported types (GameStore -> Store, GameInstance ->
Instance, GameStatus -> Status). Rename NATS subjects from game.{id}
to connect4.{id}. URL routes unchanged.

connect4/persist.go

@@ -0,0 +1,126 @@
+package connect4
+
+import (
+	"context"
+
+	"github.com/ryanhamamura/c4/db/repository"
+	"github.com/ryanhamamura/c4/player"
+
+	"github.com/rs/zerolog/log"
+)
+
+func (gi *Instance) save() error {
+	err := saveGame(gi.queries, gi.game)
+	if err != nil {
+		log.Error().Err(err).Str("game_id", gi.game.ID).Msg("failed to save game")
+	}
+	return err
+}
+
+func (gi *Instance) savePlayer(p *Player, slot int) error {
+	err := saveGamePlayer(gi.queries, gi.game.ID, p, slot)
+	if err != nil {
+		log.Error().Err(err).Str("game_id", gi.game.ID).Int("slot", slot).Msg("failed to save game player")
+	}
+	return err
+}
+
+// saveGame persists the game state via upsert.
+func saveGame(queries *repository.Queries, g *Game) error {
+	var winnerUserID *string
+	if g.Winner != nil && g.Winner.UserID != nil {
+		winnerUserID = g.Winner.UserID
+	}
+
+	var winningCells *string
+	if wc := g.WinningCellsToJSON(); wc != "" {
+		winningCells = &wc
+	}
+
+	return queries.UpsertGame(context.Background(), repository.UpsertGameParams{
+		ID:            g.ID,
+		Board:         g.BoardToJSON(),
+		CurrentTurn:   int64(g.CurrentTurn),
+		Status:        int64(g.Status),
+		WinnerUserID:  winnerUserID,
+		WinningCells:  winningCells,
+		RematchGameID: g.RematchGameID,
+	})
+}
+
+func saveGamePlayer(queries *repository.Queries, gameID string, p *Player, slot int) error {
+	var userID, guestPlayerID *string
+	if p.UserID != nil {
+		userID = p.UserID
+	} else {
+		id := string(p.ID)
+		guestPlayerID = &id
+	}
+
+	return queries.CreateGamePlayer(context.Background(), repository.CreateGamePlayerParams{
+		GameID:        gameID,
+		UserID:        userID,
+		GuestPlayerID: guestPlayerID,
+		Nickname:      p.Nickname,
+		Color:         int64(p.Color),
+		Slot:          int64(slot),
+	})
+}
+
+func loadGame(queries *repository.Queries, id string) (*Game, error) {
+	row, err := queries.GetGame(context.Background(), id)
+	if err != nil {
+		return nil, err
+	}
+	return gameFromRow(row)
+}
+
+func loadGamePlayers(queries *repository.Queries, id string) ([]*Player, error) {
+	rows, err := queries.GetGamePlayers(context.Background(), id)
+	if err != nil {
+		return nil, err
+	}
+	return playersFromRows(rows), nil
+}
+
+func gameFromRow(row *repository.Game) (*Game, error) {
+	g := &Game{
+		ID:          row.ID,
+		CurrentTurn: int(row.CurrentTurn),
+		Status:      Status(row.Status),
+	}
+
+	if err := g.BoardFromJSON(row.Board); err != nil {
+		return nil, err
+	}
+
+	if row.WinningCells != nil {
+		_ = g.WinningCellsFromJSON(*row.WinningCells)
+	}
+
+	if row.RematchGameID != nil {
+		g.RematchGameID = row.RematchGameID
+	}
+
+	return g, nil
+}
+
+func playersFromRows(rows []*repository.GamePlayer) []*Player {
+	players := make([]*Player, 0, len(rows))
+	for _, row := range rows {
+		p := &Player{
+			Nickname: row.Nickname,
+			Color:    int(row.Color),
+		}
+
+		if row.UserID != nil {
+			p.UserID = row.UserID
+			p.ID = player.ID(*row.UserID)
+		} else if row.GuestPlayerID != nil {
+			p.ID = player.ID(*row.GuestPlayerID)
+		}
+
+		players = append(players, p)
+	}
+	return players
+}