refactor(gacha): extract gacha logic into GachaService

Move payment processing, reward selection, stepup state management,
and box gacha tracking from handlers into a dedicated service layer.
Handlers now delegate to GachaService methods and only handle
protocol serialization.

server/channelserver/handlers_gacha.go

@@ -1,11 +1,6 @@
 package channelserver
 
 import (
-	"database/sql"
-	"errors"
-	"math/rand"
-	"time"
-
 	"erupe-ce/common/byteframe"
 	"erupe-ce/network/mhfpacket"
 
@@ -81,106 +76,6 @@ func handleMsgMhfUseGachaPoint(s *Session, p mhfpacket.MHFPacket) {
 	doAckSimpleSucceed(s, pkt.AckHandle, make([]byte, 4))
 }
 
-func spendGachaCoin(s *Session, quantity uint16) {
-	gt, _ := s.server.userRepo.GetTrialCoins(s.userID)
-	if quantity <= gt {
-		if err := s.server.userRepo.DeductTrialCoins(s.userID, uint32(quantity)); err != nil {
-			s.logger.Error("Failed to deduct gacha trial coins", zap.Error(err))
-		}
-	} else {
-		if err := s.server.userRepo.DeductPremiumCoins(s.userID, uint32(quantity)); err != nil {
-			s.logger.Error("Failed to deduct gacha premium coins", zap.Error(err))
-		}
-	}
-}
-
-func transactGacha(s *Session, gachaID uint32, rollID uint8) (int, error) {
-	itemType, itemNumber, rolls, err := s.server.gachaRepo.GetEntryForTransaction(gachaID, rollID)
-	if err != nil {
-		return 0, err
-	}
-	switch itemType {
-	/*
-		valid types that need manual savedata manipulation:
-		- Ryoudan Points
-		- Bond Points
-		- Image Change Points
-		valid types that work (no additional code needed):
-		- Tore Points
-		- Festa Points
-	*/
-	case 17:
-		_ = addPointNetcafe(s, int(itemNumber)*-1)
-	case 19:
-		fallthrough
-	case 20:
-		spendGachaCoin(s, itemNumber)
-	case 21:
-		if err := s.server.userRepo.DeductFrontierPoints(s.userID, uint32(itemNumber)); err != nil {
-			s.logger.Error("Failed to deduct frontier points for gacha", zap.Error(err))
-		}
-	}
-	return rolls, nil
-}
-
-func getGuaranteedItems(s *Session, gachaID uint32, rollID uint8) []GachaItem {
-	rewards, _ := s.server.gachaRepo.GetGuaranteedItems(rollID, gachaID)
-	return rewards
-}
-
-func addGachaItem(s *Session, items []GachaItem) {
-	data, _ := s.server.charRepo.LoadColumn(s.charID, "gacha_items")
-	if len(data) > 0 {
-		numItems := int(data[0])
-		data = data[1:]
-		oldItem := byteframe.NewByteFrameFromBytes(data)
-		for i := 0; i < numItems; i++ {
-			items = append(items, GachaItem{
-				ItemType: oldItem.ReadUint8(),
-				ItemID:   oldItem.ReadUint16(),
-				Quantity: oldItem.ReadUint16(),
-			})
-		}
-	}
-	newItem := byteframe.NewByteFrame()
-	newItem.WriteUint8(uint8(len(items)))
-	for i := range items {
-		newItem.WriteUint8(items[i].ItemType)
-		newItem.WriteUint16(items[i].ItemID)
-		newItem.WriteUint16(items[i].Quantity)
-	}
-	if err := s.server.charRepo.SaveColumn(s.charID, "gacha_items", newItem.Data()); err != nil {
-		s.logger.Error("Failed to update gacha items", zap.Error(err))
-	}
-}
-
-func getRandomEntries(entries []GachaEntry, rolls int, isBox bool) ([]GachaEntry, error) {
-	var chosen []GachaEntry
-	var totalWeight float64
-	for i := range entries {
-		totalWeight += entries[i].Weight
-	}
-	for rolls != len(chosen) {
-
-		if !isBox {
-			result := rand.Float64() * totalWeight
-			for _, entry := range entries {
-				result -= entry.Weight
-				if result < 0 {
-					chosen = append(chosen, entry)
-					break
-				}
-			}
-		} else {
-			result := rand.Intn(len(entries))
-			chosen = append(chosen, entries[result])
-			entries[result] = entries[len(entries)-1]
-			entries = entries[:len(entries)-1]
-		}
-	}
-	return chosen, nil
-}
-
 func handleMsgMhfReceiveGachaItem(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfReceiveGachaItem)
 	data, err := s.server.charRepo.LoadColumnWithDefault(s.charID, "gacha_items", []byte{0x00})
@@ -216,140 +111,71 @@ func handleMsgMhfReceiveGachaItem(s *Session, p mhfpacket.MHFPacket) {
 
 func handleMsgMhfPlayNormalGacha(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfPlayNormalGacha)
+
+	result, err := s.server.gachaService.PlayNormalGacha(s.userID, s.charID, pkt.GachaID, pkt.RollType)
+	if err != nil {
+		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
+		return
+	}
+
 	bf := byteframe.NewByteFrame()
-	var rewards []GachaItem
-	rolls, err := transactGacha(s, pkt.GachaID, pkt.RollType)
-	if err != nil {
-		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
-		return
+	bf.WriteUint8(uint8(len(result.Rewards)))
+	for _, r := range result.Rewards {
+		bf.WriteUint8(r.ItemType)
+		bf.WriteUint16(r.ItemID)
+		bf.WriteUint16(r.Quantity)
+		bf.WriteUint8(r.Rarity)
 	}
-
-	entries, err := s.server.gachaRepo.GetRewardPool(pkt.GachaID)
-	if err != nil {
-		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
-		return
-	}
-
-	rewardEntries, _ := getRandomEntries(entries, rolls, false)
-	temp := byteframe.NewByteFrame()
-	for i := range rewardEntries {
-		entryItems, err := s.server.gachaRepo.GetItemsForEntry(rewardEntries[i].ID)
-		if err != nil {
-			continue
-		}
-		for _, reward := range entryItems {
-			rewards = append(rewards, reward)
-			temp.WriteUint8(reward.ItemType)
-			temp.WriteUint16(reward.ItemID)
-			temp.WriteUint16(reward.Quantity)
-			temp.WriteUint8(rewardEntries[i].Rarity)
-		}
-	}
-
-	bf.WriteUint8(uint8(len(rewards)))
-	bf.WriteBytes(temp.Data())
 	doAckBufSucceed(s, pkt.AckHandle, bf.Data())
-	addGachaItem(s, rewards)
 }
 
 func handleMsgMhfPlayStepupGacha(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfPlayStepupGacha)
+
+	result, err := s.server.gachaService.PlayStepupGacha(s.userID, s.charID, pkt.GachaID, pkt.RollType)
+	if err != nil {
+		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
+		return
+	}
+
 	bf := byteframe.NewByteFrame()
-	var rewards []GachaItem
-	rolls, err := transactGacha(s, pkt.GachaID, pkt.RollType)
-	if err != nil {
-		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
-		return
-	}
-	if err := s.server.userRepo.AddFrontierPointsFromGacha(s.userID, pkt.GachaID, pkt.RollType); err != nil {
-		s.logger.Error("Failed to award stepup gacha frontier points", zap.Error(err))
-	}
-	if err := s.server.gachaRepo.DeleteStepup(pkt.GachaID, s.charID); err != nil {
-		s.logger.Error("Failed to delete gacha stepup state", zap.Error(err))
-	}
-	if err := s.server.gachaRepo.InsertStepup(pkt.GachaID, pkt.RollType+1, s.charID); err != nil {
-		s.logger.Error("Failed to insert gacha stepup state", zap.Error(err))
-	}
-
-	entries, err := s.server.gachaRepo.GetRewardPool(pkt.GachaID)
-	if err != nil {
-		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
-		return
-	}
-
-	guaranteedItems := getGuaranteedItems(s, pkt.GachaID, pkt.RollType)
-	rewardEntries, _ := getRandomEntries(entries, rolls, false)
-	temp := byteframe.NewByteFrame()
-	for i := range rewardEntries {
-		entryItems, err := s.server.gachaRepo.GetItemsForEntry(rewardEntries[i].ID)
-		if err != nil {
-			continue
-		}
-		for _, reward := range entryItems {
-			rewards = append(rewards, reward)
-			temp.WriteUint8(reward.ItemType)
-			temp.WriteUint16(reward.ItemID)
-			temp.WriteUint16(reward.Quantity)
-			temp.WriteUint8(rewardEntries[i].Rarity)
-		}
-	}
-
-	bf.WriteUint8(uint8(len(rewards) + len(guaranteedItems)))
-	bf.WriteUint8(uint8(len(rewards)))
-	for _, item := range guaranteedItems {
+	bf.WriteUint8(uint8(len(result.RandomRewards) + len(result.GuaranteedRewards)))
+	bf.WriteUint8(uint8(len(result.RandomRewards)))
+	for _, item := range result.GuaranteedRewards {
 		bf.WriteUint8(item.ItemType)
 		bf.WriteUint16(item.ItemID)
 		bf.WriteUint16(item.Quantity)
-		bf.WriteUint8(0)
+		bf.WriteUint8(item.Rarity)
+	}
+	for _, r := range result.RandomRewards {
+		bf.WriteUint8(r.ItemType)
+		bf.WriteUint16(r.ItemID)
+		bf.WriteUint16(r.Quantity)
+		bf.WriteUint8(r.Rarity)
 	}
-	bf.WriteBytes(temp.Data())
 	doAckBufSucceed(s, pkt.AckHandle, bf.Data())
-	addGachaItem(s, rewards)
-	addGachaItem(s, guaranteedItems)
 }
 
 func handleMsgMhfGetStepupStatus(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfGetStepupStatus)
 
-	// Compute the most recent noon boundary
-	midday := TimeMidnight().Add(12 * time.Hour)
-	if TimeAdjusted().Before(midday) {
-		midday = midday.Add(-24 * time.Hour)
-	}
+	status, _ := s.server.gachaService.GetStepupStatus(pkt.GachaID, s.charID, TimeAdjusted())
 
-	step, createdAt, err := s.server.gachaRepo.GetStepupWithTime(pkt.GachaID, s.charID)
-	if err != nil && !errors.Is(err, sql.ErrNoRows) {
-		s.logger.Error("Failed to get gacha stepup state", zap.Error(err))
-	}
-	// Reset stale stepup progress (created before the most recent noon)
-	if err == nil && createdAt.Before(midday) {
-		if err := s.server.gachaRepo.DeleteStepup(pkt.GachaID, s.charID); err != nil {
-			s.logger.Error("Failed to reset stale gacha stepup", zap.Error(err))
-		}
-		step = 0
-	} else if err == nil {
-		// Only check for valid entry type if the stepup is fresh
-		hasEntry, _ := s.server.gachaRepo.HasEntryType(pkt.GachaID, step)
-		if !hasEntry {
-			if err := s.server.gachaRepo.DeleteStepup(pkt.GachaID, s.charID); err != nil {
-				s.logger.Error("Failed to reset gacha stepup state", zap.Error(err))
-			}
-			step = 0
-		}
-	}
 	bf := byteframe.NewByteFrame()
-	bf.WriteUint8(step)
+	bf.WriteUint8(status.Step)
 	bf.WriteUint32(uint32(TimeAdjusted().Unix()))
 	doAckBufSucceed(s, pkt.AckHandle, bf.Data())
 }
 
 func handleMsgMhfGetBoxGachaInfo(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfGetBoxGachaInfo)
-	entryIDs, err := s.server.gachaRepo.GetBoxEntryIDs(pkt.GachaID, s.charID)
+
+	entryIDs, err := s.server.gachaService.GetBoxInfo(pkt.GachaID, s.charID)
 	if err != nil {
 		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
 		return
 	}
+
 	bf := byteframe.NewByteFrame()
 	bf.WriteUint8(uint8(len(entryIDs)))
 	for i := range entryIDs {
@@ -361,43 +187,27 @@ func handleMsgMhfGetBoxGachaInfo(s *Session, p mhfpacket.MHFPacket) {
 
 func handleMsgMhfPlayBoxGacha(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfPlayBoxGacha)
+
+	result, err := s.server.gachaService.PlayBoxGacha(s.userID, s.charID, pkt.GachaID, pkt.RollType)
+	if err != nil {
+		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
+		return
+	}
+
 	bf := byteframe.NewByteFrame()
-	var rewards []GachaItem
-	rolls, err := transactGacha(s, pkt.GachaID, pkt.RollType)
-	if err != nil {
-		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
-		return
-	}
-	entries, err := s.server.gachaRepo.GetRewardPool(pkt.GachaID)
-	if err != nil {
-		doAckBufSucceed(s, pkt.AckHandle, make([]byte, 1))
-		return
-	}
-	rewardEntries, _ := getRandomEntries(entries, rolls, true)
-	for i := range rewardEntries {
-		entryItems, err := s.server.gachaRepo.GetItemsForEntry(rewardEntries[i].ID)
-		if err != nil {
-			continue
-		}
-		if err := s.server.gachaRepo.InsertBoxEntry(pkt.GachaID, rewardEntries[i].ID, s.charID); err != nil {
-			s.logger.Error("Failed to insert gacha box entry", zap.Error(err))
-		}
-		rewards = append(rewards, entryItems...)
-	}
-	bf.WriteUint8(uint8(len(rewards)))
-	for _, r := range rewards {
+	bf.WriteUint8(uint8(len(result.Rewards)))
+	for _, r := range result.Rewards {
 		bf.WriteUint8(r.ItemType)
 		bf.WriteUint16(r.ItemID)
 		bf.WriteUint16(r.Quantity)
-		bf.WriteUint8(0)
+		bf.WriteUint8(r.Rarity)
 	}
 	doAckBufSucceed(s, pkt.AckHandle, bf.Data())
-	addGachaItem(s, rewards)
 }
 
 func handleMsgMhfResetBoxGachaInfo(s *Session, p mhfpacket.MHFPacket) {
 	pkt := p.(*mhfpacket.MsgMhfResetBoxGachaInfo)
-	if err := s.server.gachaRepo.DeleteBoxEntries(pkt.GachaID, s.charID); err != nil {
+	if err := s.server.gachaService.ResetBox(pkt.GachaID, s.charID); err != nil {
 		s.logger.Error("Failed to reset gacha box", zap.Error(err))
 	}
 	doAckSimpleSucceed(s, pkt.AckHandle, make([]byte, 4))

server/channelserver/handlers_gacha_test.go

@@ -189,6 +189,7 @@ func TestHandleMsgMhfPlayNormalGacha_TransactError(t *testing.T) {
 	gachaRepo := &mockGachaRepo{txErr: errors.New("transact failed")}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -213,6 +214,7 @@ func TestHandleMsgMhfPlayNormalGacha_RewardPoolError(t *testing.T) {
 	}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -243,6 +245,7 @@ func TestHandleMsgMhfPlayNormalGacha_Success(t *testing.T) {
 	}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -269,6 +272,7 @@ func TestHandleMsgMhfPlayStepupGacha_TransactError(t *testing.T) {
 	gachaRepo := &mockGachaRepo{txErr: errors.New("transact failed")}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -302,6 +306,7 @@ func TestHandleMsgMhfPlayStepupGacha_Success(t *testing.T) {
 	}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -331,6 +336,7 @@ func TestHandleMsgMhfGetStepupStatus_FreshStep(t *testing.T) {
 		hasEntryType: true,
 	}
 	server.gachaRepo = gachaRepo
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -354,6 +360,7 @@ func TestHandleMsgMhfGetStepupStatus_StaleStep(t *testing.T) {
 		stepupTime: time.Now().Add(-48 * time.Hour), // stale
 	}
 	server.gachaRepo = gachaRepo
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -378,6 +385,7 @@ func TestHandleMsgMhfGetStepupStatus_NoRows(t *testing.T) {
 		stepupErr: sql.ErrNoRows,
 	}
 	server.gachaRepo = gachaRepo
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -400,6 +408,7 @@ func TestHandleMsgMhfGetStepupStatus_NoEntryType(t *testing.T) {
 		hasEntryType: false, // no matching entry type -> reset
 	}
 	server.gachaRepo = gachaRepo
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -424,6 +433,7 @@ func TestHandleMsgMhfGetBoxGachaInfo_Error(t *testing.T) {
 		boxEntryIDsErr: errors.New("db error"),
 	}
 	server.gachaRepo = gachaRepo
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -444,6 +454,7 @@ func TestHandleMsgMhfGetBoxGachaInfo_Success(t *testing.T) {
 		boxEntryIDs: []uint32{10, 20, 30},
 	}
 	server.gachaRepo = gachaRepo
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -465,6 +476,7 @@ func TestHandleMsgMhfPlayBoxGacha_TransactError(t *testing.T) {
 	gachaRepo := &mockGachaRepo{txErr: errors.New("transact failed")}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -495,6 +507,7 @@ func TestHandleMsgMhfPlayBoxGacha_Success(t *testing.T) {
 	}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -517,6 +530,7 @@ func TestHandleMsgMhfResetBoxGachaInfo(t *testing.T) {
 	server := createMockServer()
 	gachaRepo := &mockGachaRepo{}
 	server.gachaRepo = gachaRepo
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 
@@ -594,6 +608,7 @@ func TestHandleMsgMhfPlayStepupGacha_RewardPoolError(t *testing.T) {
 	}
 	server.gachaRepo = gachaRepo
 	server.userRepo = &mockUserRepoGacha{}
+	ensureGachaService(server)
 
 	session := createMockSession(1, server)
 

server/channelserver/svc_gacha.go

@@ -0,0 +1,325 @@
+package channelserver
+
+import (
+	"database/sql"
+	"errors"
+	"math/rand"
+	"time"
+
+	"erupe-ce/common/byteframe"
+
+	"go.uber.org/zap"
+)
+
+// GachaService encapsulates business logic for the gacha lottery system.
+type GachaService struct {
+	gachaRepo        GachaRepo
+	userRepo         UserRepo
+	charRepo         CharacterRepo
+	logger           *zap.Logger
+	maxNetcafePoints int
+}
+
+// NewGachaService creates a new GachaService.
+func NewGachaService(gr GachaRepo, ur UserRepo, cr CharacterRepo, log *zap.Logger, maxNP int) *GachaService {
+	return &GachaService{
+		gachaRepo:        gr,
+		userRepo:         ur,
+		charRepo:         cr,
+		logger:           log,
+		maxNetcafePoints: maxNP,
+	}
+}
+
+// GachaReward represents a single gacha reward item with rarity.
+type GachaReward struct {
+	ItemType uint8
+	ItemID   uint16
+	Quantity uint16
+	Rarity   uint8
+}
+
+// GachaPlayResult holds the outcome of a normal or box gacha play.
+type GachaPlayResult struct {
+	Rewards []GachaReward
+}
+
+// StepupPlayResult holds the outcome of a stepup gacha play.
+type StepupPlayResult struct {
+	RandomRewards     []GachaReward
+	GuaranteedRewards []GachaReward
+}
+
+// StepupStatus holds the current stepup state for a character on a gacha.
+type StepupStatus struct {
+	Step uint8
+}
+
+// transact processes the cost for a gacha roll, deducting the appropriate currency.
+func (svc *GachaService) transact(userID, charID, gachaID uint32, rollID uint8) (int, error) {
+	itemType, itemNumber, rolls, err := svc.gachaRepo.GetEntryForTransaction(gachaID, rollID)
+	if err != nil {
+		return 0, err
+	}
+	switch itemType {
+	case 17:
+		svc.deductNetcafePoints(charID, int(itemNumber))
+	case 19, 20:
+		svc.spendGachaCoin(userID, itemNumber)
+	case 21:
+		if err := svc.userRepo.DeductFrontierPoints(userID, uint32(itemNumber)); err != nil {
+			svc.logger.Error("Failed to deduct frontier points for gacha", zap.Error(err))
+		}
+	}
+	return rolls, nil
+}
+
+// deductNetcafePoints removes netcafe points from a character's save data.
+func (svc *GachaService) deductNetcafePoints(charID uint32, amount int) {
+	points, err := svc.charRepo.ReadInt(charID, "netcafe_points")
+	if err != nil {
+		svc.logger.Error("Failed to read netcafe points", zap.Error(err))
+		return
+	}
+	points = min(points-amount, svc.maxNetcafePoints)
+	if err := svc.charRepo.SaveInt(charID, "netcafe_points", points); err != nil {
+		svc.logger.Error("Failed to update netcafe points", zap.Error(err))
+	}
+}
+
+// spendGachaCoin deducts gacha coins, preferring trial coins over premium.
+func (svc *GachaService) spendGachaCoin(userID uint32, quantity uint16) {
+	gt, _ := svc.userRepo.GetTrialCoins(userID)
+	if quantity <= gt {
+		if err := svc.userRepo.DeductTrialCoins(userID, uint32(quantity)); err != nil {
+			svc.logger.Error("Failed to deduct gacha trial coins", zap.Error(err))
+		}
+	} else {
+		if err := svc.userRepo.DeductPremiumCoins(userID, uint32(quantity)); err != nil {
+			svc.logger.Error("Failed to deduct gacha premium coins", zap.Error(err))
+		}
+	}
+}
+
+// resolveRewards selects random entries and resolves them into rewards.
+func (svc *GachaService) resolveRewards(entries []GachaEntry, rolls int, isBox bool) []GachaReward {
+	rewardEntries, _ := getRandomEntries(entries, rolls, isBox)
+	var rewards []GachaReward
+	for i := range rewardEntries {
+		entryItems, err := svc.gachaRepo.GetItemsForEntry(rewardEntries[i].ID)
+		if err != nil {
+			continue
+		}
+		for _, item := range entryItems {
+			rewards = append(rewards, GachaReward{
+				ItemType: item.ItemType,
+				ItemID:   item.ItemID,
+				Quantity: item.Quantity,
+				Rarity:   rewardEntries[i].Rarity,
+			})
+		}
+	}
+	return rewards
+}
+
+// saveGachaItems appends reward items to the character's gacha item storage.
+func (svc *GachaService) saveGachaItems(charID uint32, items []GachaItem) {
+	data, _ := svc.charRepo.LoadColumn(charID, "gacha_items")
+	if len(data) > 0 {
+		numItems := int(data[0])
+		data = data[1:]
+		oldItem := byteframe.NewByteFrameFromBytes(data)
+		for i := 0; i < numItems; i++ {
+			items = append(items, GachaItem{
+				ItemType: oldItem.ReadUint8(),
+				ItemID:   oldItem.ReadUint16(),
+				Quantity: oldItem.ReadUint16(),
+			})
+		}
+	}
+	newItem := byteframe.NewByteFrame()
+	newItem.WriteUint8(uint8(len(items)))
+	for i := range items {
+		newItem.WriteUint8(items[i].ItemType)
+		newItem.WriteUint16(items[i].ItemID)
+		newItem.WriteUint16(items[i].Quantity)
+	}
+	if err := svc.charRepo.SaveColumn(charID, "gacha_items", newItem.Data()); err != nil {
+		svc.logger.Error("Failed to update gacha items", zap.Error(err))
+	}
+}
+
+// rewardsToItems converts GachaReward slices to GachaItem slices for storage.
+func rewardsToItems(rewards []GachaReward) []GachaItem {
+	items := make([]GachaItem, len(rewards))
+	for i, r := range rewards {
+		items[i] = GachaItem{ItemType: r.ItemType, ItemID: r.ItemID, Quantity: r.Quantity}
+	}
+	return items
+}
+
+// PlayNormalGacha processes a normal gacha roll: deducts cost, selects random
+// rewards, saves items, and returns the result.
+func (svc *GachaService) PlayNormalGacha(userID, charID, gachaID uint32, rollType uint8) (*GachaPlayResult, error) {
+	rolls, err := svc.transact(userID, charID, gachaID, rollType)
+	if err != nil {
+		return nil, err
+	}
+	entries, err := svc.gachaRepo.GetRewardPool(gachaID)
+	if err != nil {
+		return nil, err
+	}
+	rewards := svc.resolveRewards(entries, rolls, false)
+	svc.saveGachaItems(charID, rewardsToItems(rewards))
+	return &GachaPlayResult{Rewards: rewards}, nil
+}
+
+// PlayStepupGacha processes a stepup gacha roll: deducts cost, advances step,
+// awards frontier points, selects random + guaranteed rewards, and saves items.
+func (svc *GachaService) PlayStepupGacha(userID, charID, gachaID uint32, rollType uint8) (*StepupPlayResult, error) {
+	rolls, err := svc.transact(userID, charID, gachaID, rollType)
+	if err != nil {
+		return nil, err
+	}
+	if err := svc.userRepo.AddFrontierPointsFromGacha(userID, gachaID, rollType); err != nil {
+		svc.logger.Error("Failed to award stepup gacha frontier points", zap.Error(err))
+	}
+	if err := svc.gachaRepo.DeleteStepup(gachaID, charID); err != nil {
+		svc.logger.Error("Failed to delete gacha stepup state", zap.Error(err))
+	}
+	if err := svc.gachaRepo.InsertStepup(gachaID, rollType+1, charID); err != nil {
+		svc.logger.Error("Failed to insert gacha stepup state", zap.Error(err))
+	}
+
+	entries, err := svc.gachaRepo.GetRewardPool(gachaID)
+	if err != nil {
+		return nil, err
+	}
+
+	guaranteedItems, _ := svc.gachaRepo.GetGuaranteedItems(rollType, gachaID)
+	randomRewards := svc.resolveRewards(entries, rolls, false)
+
+	var guaranteedRewards []GachaReward
+	for _, item := range guaranteedItems {
+		guaranteedRewards = append(guaranteedRewards, GachaReward{
+			ItemType: item.ItemType,
+			ItemID:   item.ItemID,
+			Quantity: item.Quantity,
+			Rarity:   0,
+		})
+	}
+
+	svc.saveGachaItems(charID, rewardsToItems(randomRewards))
+	svc.saveGachaItems(charID, rewardsToItems(guaranteedRewards))
+	return &StepupPlayResult{
+		RandomRewards:     randomRewards,
+		GuaranteedRewards: guaranteedRewards,
+	}, nil
+}
+
+// PlayBoxGacha processes a box gacha roll: deducts cost, selects random entries
+// without replacement, records drawn entries, saves items, and returns the result.
+func (svc *GachaService) PlayBoxGacha(userID, charID, gachaID uint32, rollType uint8) (*GachaPlayResult, error) {
+	rolls, err := svc.transact(userID, charID, gachaID, rollType)
+	if err != nil {
+		return nil, err
+	}
+	entries, err := svc.gachaRepo.GetRewardPool(gachaID)
+	if err != nil {
+		return nil, err
+	}
+	rewardEntries, _ := getRandomEntries(entries, rolls, true)
+	var rewards []GachaReward
+	for i := range rewardEntries {
+		entryItems, err := svc.gachaRepo.GetItemsForEntry(rewardEntries[i].ID)
+		if err != nil {
+			continue
+		}
+		if err := svc.gachaRepo.InsertBoxEntry(gachaID, rewardEntries[i].ID, charID); err != nil {
+			svc.logger.Error("Failed to insert gacha box entry", zap.Error(err))
+		}
+		for _, item := range entryItems {
+			rewards = append(rewards, GachaReward{
+				ItemType: item.ItemType,
+				ItemID:   item.ItemID,
+				Quantity: item.Quantity,
+				Rarity:   0,
+			})
+		}
+	}
+	svc.saveGachaItems(charID, rewardsToItems(rewards))
+	return &GachaPlayResult{Rewards: rewards}, nil
+}
+
+// GetStepupStatus returns the current stepup step for a character, resetting
+// stale progress based on the noon boundary. The now parameter enables
+// deterministic testing.
+func (svc *GachaService) GetStepupStatus(gachaID, charID uint32, now time.Time) (*StepupStatus, error) {
+	// Compute the most recent noon boundary
+	y, m, d := now.Date()
+	midday := time.Date(y, m, d, 12, 0, 0, 0, now.Location())
+	if now.Before(midday) {
+		midday = midday.Add(-24 * time.Hour)
+	}
+
+	step, createdAt, err := svc.gachaRepo.GetStepupWithTime(gachaID, charID)
+	if err != nil && !errors.Is(err, sql.ErrNoRows) {
+		svc.logger.Error("Failed to get gacha stepup state", zap.Error(err))
+	}
+
+	if err == nil && createdAt.Before(midday) {
+		if err := svc.gachaRepo.DeleteStepup(gachaID, charID); err != nil {
+			svc.logger.Error("Failed to reset stale gacha stepup", zap.Error(err))
+		}
+		step = 0
+	} else if err == nil {
+		hasEntry, _ := svc.gachaRepo.HasEntryType(gachaID, step)
+		if !hasEntry {
+			if err := svc.gachaRepo.DeleteStepup(gachaID, charID); err != nil {
+				svc.logger.Error("Failed to reset gacha stepup state", zap.Error(err))
+			}
+			step = 0
+		}
+	}
+
+	return &StepupStatus{Step: step}, nil
+}
+
+// GetBoxInfo returns the entry IDs already drawn for a box gacha.
+func (svc *GachaService) GetBoxInfo(gachaID, charID uint32) ([]uint32, error) {
+	return svc.gachaRepo.GetBoxEntryIDs(gachaID, charID)
+}
+
+// ResetBox clears all drawn entries for a box gacha.
+func (svc *GachaService) ResetBox(gachaID, charID uint32) error {
+	return svc.gachaRepo.DeleteBoxEntries(gachaID, charID)
+}
+
+// getRandomEntries selects random gacha entries. In non-box mode, entries are
+// chosen with weighted probability (with replacement). In box mode, entries are
+// chosen uniformly without replacement.
+func getRandomEntries(entries []GachaEntry, rolls int, isBox bool) ([]GachaEntry, error) {
+	var chosen []GachaEntry
+	var totalWeight float64
+	for i := range entries {
+		totalWeight += entries[i].Weight
+	}
+	for rolls != len(chosen) {
+		if !isBox {
+			result := rand.Float64() * totalWeight
+			for _, entry := range entries {
+				result -= entry.Weight
+				if result < 0 {
+					chosen = append(chosen, entry)
+					break
+				}
+			}
+		} else {
+			result := rand.Intn(len(entries))
+			chosen = append(chosen, entries[result])
+			entries[result] = entries[len(entries)-1]
+			entries = entries[:len(entries)-1]
+		}
+	}
+	return chosen, nil
+}

server/channelserver/svc_gacha_test.go

@@ -0,0 +1,316 @@
+package channelserver
+
+import (
+	"database/sql"
+	"errors"
+	"testing"
+	"time"
+
+	"go.uber.org/zap"
+)
+
+func newTestGachaService(gr GachaRepo, ur UserRepo, cr CharacterRepo) *GachaService {
+	logger, _ := zap.NewDevelopment()
+	return NewGachaService(gr, ur, cr, logger, 100000)
+}
+
+func TestGachaService_PlayNormalGacha(t *testing.T) {
+	tests := []struct {
+		name      string
+		txErr     error
+		poolErr   error
+		txRolls   int
+		pool      []GachaEntry
+		items     map[uint32][]GachaItem
+		wantErr   bool
+		wantCount int
+	}{
+		{
+			name:    "transact error",
+			txErr:   errors.New("tx fail"),
+			wantErr: true,
+		},
+		{
+			name:    "reward pool error",
+			txRolls: 1,
+			poolErr: errors.New("pool fail"),
+			wantErr: true,
+		},
+		{
+			name:    "success single roll",
+			txRolls: 1,
+			pool:    []GachaEntry{{ID: 10, Weight: 100, Rarity: 3}},
+			items: map[uint32][]GachaItem{
+				10: {{ItemType: 1, ItemID: 500, Quantity: 1}},
+			},
+			wantCount: 1,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gr := &mockGachaRepo{
+				txRolls:       tt.txRolls,
+				txErr:         tt.txErr,
+				rewardPool:    tt.pool,
+				rewardPoolErr: tt.poolErr,
+				entryItems:    tt.items,
+			}
+			cr := newMockCharacterRepo()
+			svc := newTestGachaService(gr, &mockUserRepoGacha{}, cr)
+
+			result, err := svc.PlayNormalGacha(1, 1, 1, 0)
+			if tt.wantErr {
+				if err == nil {
+					t.Fatal("Expected error, got nil")
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("Unexpected error: %v", err)
+			}
+			if len(result.Rewards) != tt.wantCount {
+				t.Errorf("Rewards count = %d, want %d", len(result.Rewards), tt.wantCount)
+			}
+			// Verify items were saved
+			if tt.wantCount > 0 && cr.columns["gacha_items"] == nil {
+				t.Error("Expected gacha items to be saved")
+			}
+		})
+	}
+}
+
+func TestGachaService_PlayStepupGacha(t *testing.T) {
+	tests := []struct {
+		name               string
+		txErr              error
+		poolErr            error
+		txRolls            int
+		pool               []GachaEntry
+		items              map[uint32][]GachaItem
+		guaranteed         []GachaItem
+		wantErr            bool
+		wantRandomCount    int
+		wantGuaranteeCount int
+	}{
+		{
+			name:    "transact error",
+			txErr:   errors.New("tx fail"),
+			wantErr: true,
+		},
+		{
+			name:    "reward pool error",
+			txRolls: 1,
+			poolErr: errors.New("pool fail"),
+			wantErr: true,
+		},
+		{
+			name:    "success with guaranteed",
+			txRolls: 1,
+			pool:    []GachaEntry{{ID: 10, Weight: 100, Rarity: 2}},
+			items: map[uint32][]GachaItem{
+				10: {{ItemType: 1, ItemID: 600, Quantity: 2}},
+			},
+			guaranteed:         []GachaItem{{ItemType: 1, ItemID: 700, Quantity: 1}},
+			wantRandomCount:    1,
+			wantGuaranteeCount: 1,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gr := &mockGachaRepo{
+				txRolls:         tt.txRolls,
+				txErr:           tt.txErr,
+				rewardPool:      tt.pool,
+				rewardPoolErr:   tt.poolErr,
+				entryItems:      tt.items,
+				guaranteedItems: tt.guaranteed,
+			}
+			cr := newMockCharacterRepo()
+			svc := newTestGachaService(gr, &mockUserRepoGacha{}, cr)
+
+			result, err := svc.PlayStepupGacha(1, 1, 1, 0)
+			if tt.wantErr {
+				if err == nil {
+					t.Fatal("Expected error, got nil")
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("Unexpected error: %v", err)
+			}
+			if len(result.RandomRewards) != tt.wantRandomCount {
+				t.Errorf("RandomRewards count = %d, want %d", len(result.RandomRewards), tt.wantRandomCount)
+			}
+			if len(result.GuaranteedRewards) != tt.wantGuaranteeCount {
+				t.Errorf("GuaranteedRewards count = %d, want %d", len(result.GuaranteedRewards), tt.wantGuaranteeCount)
+			}
+			if !gr.deletedStepup {
+				t.Error("Expected stepup to be deleted")
+			}
+			if gr.insertedStep != 1 {
+				t.Errorf("Expected insertedStep=1, got %d", gr.insertedStep)
+			}
+		})
+	}
+}
+
+func TestGachaService_PlayBoxGacha(t *testing.T) {
+	gr := &mockGachaRepo{
+		txRolls: 1,
+		rewardPool: []GachaEntry{
+			{ID: 10, Weight: 100, Rarity: 1},
+		},
+		entryItems: map[uint32][]GachaItem{
+			10: {{ItemType: 1, ItemID: 800, Quantity: 1}},
+		},
+	}
+	cr := newMockCharacterRepo()
+	svc := newTestGachaService(gr, &mockUserRepoGacha{}, cr)
+
+	result, err := svc.PlayBoxGacha(1, 1, 1, 0)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	if len(result.Rewards) != 1 {
+		t.Errorf("Rewards count = %d, want 1", len(result.Rewards))
+	}
+	if len(gr.insertedBoxIDs) == 0 {
+		t.Error("Expected box entry to be inserted")
+	}
+}
+
+func TestGachaService_GetStepupStatus(t *testing.T) {
+	now := time.Date(2025, 6, 15, 15, 0, 0, 0, time.UTC) // 3 PM
+	midday := time.Date(2025, 6, 15, 12, 0, 0, 0, time.UTC)
+
+	tests := []struct {
+		name        string
+		step        uint8
+		createdAt   time.Time
+		stepupErr   error
+		hasEntry    bool
+		wantStep    uint8
+		wantDeleted bool
+	}{
+		{
+			name:      "no rows",
+			stepupErr: sql.ErrNoRows,
+			wantStep:  0,
+		},
+		{
+			name:        "fresh with entry",
+			step:        2,
+			createdAt:   now, // after midday
+			hasEntry:    true,
+			wantStep:    2,
+			wantDeleted: false,
+		},
+		{
+			name:        "stale (before midday)",
+			step:        3,
+			createdAt:   midday.Add(-1 * time.Hour), // before midday boundary
+			wantStep:    0,
+			wantDeleted: true,
+		},
+		{
+			name:        "fresh but no entry type",
+			step:        2,
+			createdAt:   now,
+			hasEntry:    false,
+			wantStep:    0,
+			wantDeleted: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gr := &mockGachaRepo{
+				stepupStep:   tt.step,
+				stepupTime:   tt.createdAt,
+				stepupErr:    tt.stepupErr,
+				hasEntryType: tt.hasEntry,
+			}
+			svc := newTestGachaService(gr, &mockUserRepoGacha{}, newMockCharacterRepo())
+
+			status, err := svc.GetStepupStatus(1, 1, now)
+			if err != nil {
+				t.Fatalf("Unexpected error: %v", err)
+			}
+			if status.Step != tt.wantStep {
+				t.Errorf("Step = %d, want %d", status.Step, tt.wantStep)
+			}
+			if gr.deletedStepup != tt.wantDeleted {
+				t.Errorf("deletedStepup = %v, want %v", gr.deletedStepup, tt.wantDeleted)
+			}
+		})
+	}
+}
+
+func TestGachaService_GetBoxInfo(t *testing.T) {
+	gr := &mockGachaRepo{
+		boxEntryIDs: []uint32{10, 20, 30},
+	}
+	svc := newTestGachaService(gr, &mockUserRepoGacha{}, newMockCharacterRepo())
+
+	ids, err := svc.GetBoxInfo(1, 1)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	if len(ids) != 3 {
+		t.Errorf("Got %d entry IDs, want 3", len(ids))
+	}
+}
+
+func TestGachaService_ResetBox(t *testing.T) {
+	gr := &mockGachaRepo{}
+	svc := newTestGachaService(gr, &mockUserRepoGacha{}, newMockCharacterRepo())
+
+	err := svc.ResetBox(1, 1)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	if !gr.deletedBox {
+		t.Error("Expected box entries to be deleted")
+	}
+}
+
+func TestGachaService_Transact_NetcafeCoins(t *testing.T) {
+	cr := newMockCharacterRepo()
+	cr.ints["netcafe_points"] = 5000
+	gr := &mockGachaRepo{
+		txItemType:   17,
+		txItemNumber: 100,
+		txRolls:      1,
+	}
+	svc := newTestGachaService(gr, &mockUserRepoGacha{}, cr)
+
+	rolls, err := svc.transact(1, 1, 1, 0)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	if rolls != 1 {
+		t.Errorf("Rolls = %d, want 1", rolls)
+	}
+	// Netcafe points should have been reduced
+	if cr.ints["netcafe_points"] != 4900 {
+		t.Errorf("Netcafe points = %d, want 4900", cr.ints["netcafe_points"])
+	}
+}
+
+func TestGachaService_SpendGachaCoin_TrialFirst(t *testing.T) {
+	ur := &mockUserRepoGacha{trialCoins: 100}
+	svc := newTestGachaService(&mockGachaRepo{}, ur, newMockCharacterRepo())
+
+	svc.spendGachaCoin(1, 50)
+	// Should have used trial coins, not premium
+}
+
+func TestGachaService_SpendGachaCoin_PremiumFallback(t *testing.T) {
+	ur := &mockUserRepoGacha{trialCoins: 10}
+	svc := newTestGachaService(&mockGachaRepo{}, ur, newMockCharacterRepo())
+
+	svc.spendGachaCoin(1, 50)
+	// Should have used premium coins since trial < quantity
+}

server/channelserver/sys_channel_server.go

@@ -73,6 +73,7 @@ type Server struct {
 	mercenaryRepo   MercenaryRepo
 	guildService       *GuildService
 	achievementService *AchievementService
+	gachaService       *GachaService
 	erupeConfig     *cfg.Config
 	acceptConns     chan net.Conn
 	deleteConns     chan net.Conn
@@ -157,6 +158,7 @@ func NewServer(config *Config) *Server {
 
 	s.guildService = NewGuildService(s.guildRepo, s.mailRepo, s.charRepo, s.logger)
 	s.achievementService = NewAchievementService(s.achievementRepo, s.logger)
+	s.gachaService = NewGachaService(s.gachaRepo, s.userRepo, s.charRepo, s.logger, config.ErupeConfig.GameplayOptions.MaximumNP)
 
 	// Mezeporta
 	s.stages.Store("sl1Ns200p0a0u0", NewStage("sl1Ns200p0a0u0"))

server/channelserver/test_helpers_test.go

@@ -66,6 +66,11 @@ func ensureAchievementService(s *Server) {
 	s.achievementService = NewAchievementService(s.achievementRepo, s.logger)
 }
 
+// ensureGachaService wires the GachaService from the server's current repos.
+func ensureGachaService(s *Server) {
+	s.gachaService = NewGachaService(s.gachaRepo, s.userRepo, s.charRepo, s.logger, 100000)
+}
+
 // createMockSession creates a minimal Session for testing.
 // Imported from v9.2.x-stable and adapted for main.
 func createMockSession(charID uint32, server *Server) *Session {