fix: atomic saves, casino RNG/config isolation, tick lifecycle

1 files changed, 119 insertions, 0 deletions

diff --git a/internal/casino/config_validate.go b/internal/casino/config_validate.go
new file mode 100644
index 0000000..13229bc
--- /dev/null
+++ b/internal/casino/config_validate.go
@@ -0,0 +1,119 @@
+package casino
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	"strings"
+)
+
+// Validate checks raw configuration before Normalize supplies omitted (zero)
+// defaults. Invalid explicit values must not silently become house rules.
+func (c MachineConfig) Validate() error {
+	if err := validateIdentityAndBets(c.ID, c.MinBet, c.MaxBet); err != nil {
+		return err
+	}
+	if c.Game != GameSlots {
+		return fmt.Errorf("unsupported machine game %q", c.Game)
+	}
+	if c.Variant != "" && c.Variant != "huff_and_even_more_puff" {
+		return fmt.Errorf("unsupported slots variant %q", c.Variant)
+	}
+	if c.SpinTicks < 0 {
+		return fmt.Errorf("spin_ticks must not be negative")
+	}
+	if !finiteNonnegative(c.Payout) || c.Payout > 1 {
+		return fmt.Errorf("payout must be finite and between 0 and 1 (0 uses the default)")
+	}
+	return nil
+}
+
+func (c TableConfig) Validate() error {
+	if err := validateIdentityAndBets(c.ID, c.MinBet, c.MaxBet); err != nil {
+		return err
+	}
+	if c.MaxPlayers < 0 || c.BettingTicks < 0 {
+		return fmt.Errorf("max_players and betting_ticks must not be negative")
+	}
+	switch c.Game {
+	case GameBlackjack:
+		b := c.Blackjack
+		if err := validateShoe(b.Decks, b.ShuffleAt); err != nil {
+			return err
+		}
+		if b.MaxSplitHands < 0 || b.ActionTicks < 0 {
+			return fmt.Errorf("max_split_hands and action_ticks must not be negative")
+		}
+		if !finiteNonnegative(b.BlackjackPayout) || !finiteNonnegative(b.InsurancePayout) {
+			return fmt.Errorf("blackjack_payout and insurance_payout must be finite and nonnegative")
+		}
+	case GameBaccarat:
+		b := c.Baccarat
+		if err := validateShoe(b.Decks, b.ShuffleAt); err != nil {
+			return err
+		}
+		if !finiteNonnegative(b.TiePayout) || !finiteNonnegative(b.BankerPayout) {
+			return fmt.Errorf("tie_payout and banker_payout must be finite and nonnegative")
+		}
+	default:
+		return fmt.Errorf("unsupported table game %q", c.Game)
+	}
+	return nil
+}
+
+func validateIdentityAndBets(id string, minBet, maxBet int) error {
+	if id == "" || strings.TrimSpace(id) != id {
+		return fmt.Errorf("id must be nonempty with no surrounding whitespace")
+	}
+	if minBet < 0 || maxBet < 0 {
+		return fmt.Errorf("min_bet and max_bet must not be negative")
+	}
+	if maxBet > 0 && maxBet < max(1, minBet) {
+		return fmt.Errorf("max_bet must be at least min_bet")
+	}
+	return nil
+}
+
+func finiteNonnegative(n float64) bool {
+	return !math.IsNaN(n) && !math.IsInf(n, 0) && n >= 0
+}
+
+func validateShoe(decks int, shuffleAt float64) error {
+	// A generous resource limit prevents malformed content from allocating an
+	// unbounded shoe. Zero retains the existing eight-deck default.
+	if decks < 0 || decks > 64 {
+		return fmt.Errorf("decks must be between 0 and 64 (0 uses the default)")
+	}
+	if !finiteNonnegative(shuffleAt) || shuffleAt >= 1 {
+		return fmt.Errorf("shuffle_at must be finite and in [0, 1)")
+	}
+	return nil
+}
+
+// ValidateRoomConfigs checks the shared room-local ID namespace as well as
+// individual definitions. Legacy slots under casino_tables remain supported.
+func ValidateRoomConfigs(tables []TableConfig, machines []MachineConfig) error {
+	seen := make(map[string]bool)
+	var errs []error
+	check := func(kind, id string, err error) {
+		if seen[id] {
+			errs = append(errs, fmt.Errorf("duplicate casino id %q", id))
+		}
+		seen[id] = true
+		if err != nil {
+			errs = append(errs, fmt.Errorf("%s %q: %w", kind, id, err))
+		}
+	}
+	for _, c := range tables {
+		if c.Game == GameSlots {
+			legacy := MachineConfig{ID: c.ID, Game: GameSlots, MinBet: c.MinBet, MaxBet: c.MaxBet}
+			check("legacy slots", c.ID, legacy.Validate())
+		} else {
+			check("table", c.ID, c.Validate())
+		}
+	}
+	for _, c := range machines {
+		check("machine", c.ID, c.Validate())
+	}
+	return errors.Join(errs...)
+}