fix: harden engine across casino, economy, concurrency, security, and content

1 files changed, 51 insertions, 26 deletions

diff --git a/internal/game/act_farm.go b/internal/game/act_farm.go
index 1e576c3..48fbec7 100644
--- a/internal/game/act_farm.go
+++ b/internal/game/act_farm.go
@@ -242,43 +242,68 @@ func (g *Game) advanceHarvest(sess *net.Session, p *player.Player) {
 	bonus := p.Level(player.Farming) / 20
 	yield += bonus
 
-	freeSlots := p.FreeSlots()
-	if yield > freeSlots {
-		productDef, _ := g.ItemStore.Load(product)
-		if productDef == nil || !productDef.Stackable {
+	productDef, _ := g.ItemStore.Load(product)
+	stackable := productDef != nil && productDef.Stackable
+
+	// The delivery target is chosen before the crop is consumed: a harvest
+	// that cannot be stored must leave the patch ready instead of being
+	// silently destroyed. A stackable product merges into an existing stack
+	// and therefore needs no free slot.
+	mergeSlot := -1
+	freeSlot := -1
+	noRoom := false
+	if stackable {
+		quality, maxQuality := stackProps(productDef)
+		for i := 0; i < 28; i++ {
+			s := p.InvSlot(i)
+			// Only a stack with the properties a fresh harvest stack gets
+			// may absorb it; merging into a differently qualified stack
+			// would silently destroy one of the two qualities.
+			if s != nil && s.ItemID == product && s.Quality == quality && s.MaxQuality == maxQuality {
+				mergeSlot = i
+				break
+			}
+		}
+		if mergeSlot < 0 {
+			freeSlot = p.FirstFreeSlot()
+		}
+		noRoom = mergeSlot < 0 && freeSlot < 0
+	} else {
+		// One slot per unit: the clamp and the placement loop must count
+		// slots the same way (a nil 0..27 slot).
+		freeSlots := 0
+		for i := 0; i < 28; i++ {
+			if p.InvSlot(i) == nil {
+				freeSlots++
+			}
+		}
+		if yield > freeSlots {
 			yield = freeSlots
 		}
+		noRoom = yield <= 0
 	}
-	if yield <= 0 {
+	if noRoom {
 		sess.WriteLine("Your inventory is too full!")
 		p.Action = nil
 		return
 	}
 
-	productDef, _ := g.ItemStore.Load(product)
-	if productDef != nil && productDef.Stackable {
-		added := 0
-		for i := 0; i < 28 && added < yield; i++ {
-			slot := p.InvSlot(i)
-			if slot != nil && slot.ItemID == product {
-				slot.Quantity += yield
-				added = yield
-				break
-			}
-		}
-		if added == 0 {
-			freeSlot := p.FirstFreeSlot()
-			if freeSlot >= 0 {
-				p.SetInvSlot(freeSlot, &player.InventorySlot{ItemID: product, Quantity: yield})
-			}
+	placed := yield
+	if stackable {
+		if mergeSlot >= 0 {
+			p.InvSlot(mergeSlot).Quantity += yield
+		} else {
+			p.SetInvSlot(freeSlot, g.newInventorySlot(product, yield))
 		}
 	} else {
-		for i := 0; i < yield; i++ {
-			freeSlot := p.FirstFreeSlot()
-			if freeSlot < 0 {
+		placed = 0
+		for placed < yield {
+			fs := p.FirstFreeSlot()
+			if fs < 0 {
 				break
 			}
-			p.SetInvSlot(freeSlot, &player.InventorySlot{ItemID: product, Quantity: 1})
+			p.SetInvSlot(fs, g.newInventorySlot(product, 1))
+			placed++
 		}
 	}
 
@@ -302,7 +327,7 @@ func (g *Game) advanceHarvest(sess *net.Session, p *player.Player) {
 		productName = g.itemColorize(sess, productDef, productDef.Name)
 	}
 	patchName := patchDisplayName(prefix)
-	msg := fmt.Sprintf("You harvest %d %s from the %s.", yield, productName, patchName)
+	msg := fmt.Sprintf("You harvest %d %s from the %s.", placed, productName, patchName)
 	if int(xp) > 0 && p.OptionBool("xp_drops") {
 		msg += g.formatXpDropSingle(sess, p, player.Farming, int(xp))
 	}