Fix gold able to over- and underflow (#4065)

core/src/com/unciv/logic/battle/Battle.kt

@@ -122,7 +122,7 @@ object Battle {
         }
 
         civUnit.getCivInfo().policies.addCulture(cultureReward)
-        civUnit.getCivInfo().gold += goldReward
+        civUnit.getCivInfo().addGold(goldReward)
     }
 
     private fun takeDamage(attacker: ICombatant, defender: ICombatant) {
@@ -203,7 +203,7 @@ object Battle {
                 && attacker.getCivInfo().hasUnique("67% chance to earn 25 Gold and recruit a Barbarian unit from a conquered encampment")
                 && Random().nextDouble() < 0.67) {
             attacker.getCivInfo().placeUnitNearTile(attackedTile.position, defender.getName())
-            attacker.getCivInfo().gold += 25
+            attacker.getCivInfo().addGold(25)
             attacker.getCivInfo().addNotification("A barbarian [${defender.getName()}] has joined us!", attackedTile.position, defender.getName())
         }
 
@@ -213,7 +213,7 @@ object Battle {
                 && attacker.getCivInfo().hasUnique("50% chance of capturing defeated Barbarian naval units and earning 25 Gold")
                 && Random().nextDouble() > 0.5) {
             attacker.getCivInfo().placeUnitNearTile(attackedTile.position, defender.getName())
-            attacker.getCivInfo().gold += 25
+            attacker.getCivInfo().addGold(25)
         }
     }
 

core/src/com/unciv/logic/city/CityConstructions.kt

@@ -397,7 +397,7 @@ class CityConstructions {
             return false // nothing built - no pay
 
         if (!cityInfo.civInfo.gameInfo.gameParameters.godMode)
-            cityInfo.civInfo.gold -= getConstruction(constructionName).getGoldCost(cityInfo.civInfo)
+            cityInfo.civInfo.addGold(-getConstruction(constructionName).getGoldCost(cityInfo.civInfo))
 
         if (queuePosition in 0 until constructionQueue.size)
             removeFromQueue(queuePosition, automatic)

core/src/com/unciv/logic/city/CityExpansionManager.kt

@@ -51,7 +51,7 @@ class CityExpansionManager {
         class NotEnoughGoldToBuyTileException : Exception()
         if (cityInfo.civInfo.gold < goldCost && !cityInfo.civInfo.gameInfo.gameParameters.godMode)
             throw NotEnoughGoldToBuyTileException()
-        cityInfo.civInfo.gold -= goldCost
+        cityInfo.civInfo.addGold(-goldCost)
         takeOwnership(tileInfo)
     }
 

core/src/com/unciv/logic/city/CityInfo.kt

@@ -427,7 +427,7 @@ class CityInfo {
 
     fun sellBuilding(buildingName: String) {
         cityConstructions.removeBuilding(buildingName)
-        civInfo.gold += getGoldForSellingBuilding(buildingName)
+        civInfo.addGold(getGoldForSellingBuilding(buildingName))
         hasSoldBuildingThisTurn = true
 
         population.unassignExtraPopulation() // If the building provided specialists, release them to other work

core/src/com/unciv/logic/city/CityInfoConquestFunctions.kt

@@ -32,7 +32,7 @@ class CityInfoConquestFunctions(val city: CityInfo){
         // Gain gold for plundering city
         val goldPlundered = getGoldForCapturingCity(conqueringCiv)
         city.apply {
-            conqueringCiv.gold += goldPlundered
+            conqueringCiv.addGold(goldPlundered)
             conqueringCiv.addNotification("Received [$goldPlundered] Gold for capturing [$name]", getCenterTile().position, NotificationIcon.Gold)
 
             val oldCiv = civInfo

core/src/com/unciv/logic/civilization/CivInfoTransientUpdater.kt

@@ -107,7 +107,7 @@ class CivInfoTransientUpdater(val civInfo: CivilizationInfo) {
             }
 
             if (goldGained > 0) {
-                civInfo.gold += goldGained
+                civInfo.addGold(goldGained)
                 civInfo.addNotification("We have received [" + goldGained + "] Gold for discovering [" + tile.naturalWonder + "]", NotificationIcon.Gold)
             }
 

core/src/com/unciv/logic/civilization/CivilizationInfo.kt

@@ -523,7 +523,7 @@ class CivilizationInfo {
             }
         }
 
-        gold += nextTurnStats.gold.toInt()
+        addGold( nextTurnStats.gold.toInt() )
 
         if (cities.isNotEmpty() && gameInfo.ruleSet.technologies.isNotEmpty())
             tech.endTurn(nextTurnStats.science.toInt())
@@ -543,6 +543,14 @@ class CivilizationInfo {
         updateHasActiveGreatWall()
     }
 
+    fun addGold(delta: Int) {
+        gold = when {
+            delta > 0 && gold > Int.MAX_VALUE - delta -> Int.MAX_VALUE
+            delta < 0 && gold < Int.MIN_VALUE - delta -> Int.MIN_VALUE
+            else -> gold + delta
+        }
+    }
+
     fun getGreatPersonPointsForNextTurn(): Stats {
         val stats = Stats()
         for (city in cities) stats.add(city.getGreatPersonPoints())
@@ -619,7 +627,8 @@ class CivilizationInfo {
 
     fun giveGoldGift(cityState: CivilizationInfo, giftAmount: Int) {
         if (!cityState.isCityState()) throw Exception("You can only gain influence with City-States!")
-        gold -= giftAmount
+        addGold(-giftAmount)
+        cityState.addGold(giftAmount)
         cityState.getDiplomacyManager(this).influence += influenceGainedByGift(cityState, giftAmount)
         cityState.updateAllyCivForCityState()
         updateStatsForNextTurn()

core/src/com/unciv/logic/map/MapUnit.kt

@@ -631,7 +631,7 @@ class MapUnit {
         if (civInfo.hasUnique("Receive triple Gold from Barbarian encampments and pillaging Cities"))
             goldGained *= 3f
 
-        civInfo.gold += goldGained.toInt()
+        civInfo.addGold(goldGained.toInt())
         civInfo.addNotification(
             "We have captured a barbarian encampment and recovered [${goldGained.toInt()}] gold!",
             tile.position,
@@ -660,7 +660,7 @@ class MapUnit {
 
         destroy()
         if (currentTile.getOwner() == civInfo)
-            civInfo.gold += baseUnit.getDisbandGold(civInfo)
+            civInfo.addGold(baseUnit.getDisbandGold(civInfo))
         if (civInfo.isDefeated()) civInfo.destroy()
     }
 
@@ -725,7 +725,7 @@ class MapUnit {
 
         actions.add {
             val amount = listOf(25, 60, 100).random(tileBasedRandom)
-            civInfo.gold += amount
+            civInfo.addGold(amount)
             civInfo.addNotification(
                 "We have found a stash of [$amount] gold in the ruins!",
                 tile.position,

core/src/com/unciv/logic/trade/TradeLogic.kt

@@ -79,8 +79,8 @@ class TradeLogic(val ourCivilization:CivilizationInfo, val otherCivilization: Ci
         fun transferTrade(to: CivilizationInfo, from: CivilizationInfo, trade: Trade) {
             for (offer in trade.theirOffers) {
                 if (offer.type == TradeType.Gold) {
-                    to.gold += offer.amount
+                    to.addGold(offer.amount)
-                    from.gold -= offer.amount
+                    from.addGold(-offer.amount)
                 }
                 if (offer.type == TradeType.Technology) {
                     to.tech.addTechnology(offer.name)
@@ -95,7 +95,7 @@ class TradeLogic(val ourCivilization:CivilizationInfo, val otherCivilization: Ci
                 if (offer.type == TradeType.Treaty) {
                     if (offer.name == Constants.peaceTreaty) to.getDiplomacyManager(from).makePeace()
                     if (offer.name == Constants.researchAgreement) {
-                        to.gold -= offer.amount
+                        to.addGold(-offer.amount)
                         to.getDiplomacyManager(from).setFlag(DiplomacyFlags.ResearchAgreement, offer.duration)
                     }
                 }

core/src/com/unciv/ui/worldscreen/WorldScreenTopBar.kt

@@ -198,7 +198,7 @@ class WorldScreenTopBar(val worldScreen: WorldScreen) : Table() {
 
         val nextTurnStats = civInfo.statsForNextTurn
         val goldPerTurn = "(" + (if (nextTurnStats.gold > 0) "+" else "") + nextTurnStats.gold.roundToInt() + ")"
-        goldLabel.setText(civInfo.gold.toFloat().roundToInt().toString() + goldPerTurn)
+        goldLabel.setText(civInfo.gold.toString() + goldPerTurn)
 
         scienceLabel.setText("+" + nextTurnStats.science.roundToInt())
 

core/src/com/unciv/ui/worldscreen/unit/UnitActions.kt

@@ -235,7 +235,7 @@ object UnitActions {
                 title = "Upgrade to [${upgradedUnit.name}] ([$goldCostOfUpgrade] gold)",
                 uncivSound = UncivSound.Upgrade,
                 action = {
-                    unit.civInfo.gold -= goldCostOfUpgrade
+                    unit.civInfo.addGold(-goldCostOfUpgrade)
                     val unitTile = unit.getTile()
                     unit.destroy()
                     val newunit = unit.civInfo.placeUnitNearTile(unitTile.position, upgradedUnit.name)!!
@@ -334,7 +334,7 @@ object UnitActions {
                             var goldEarned = ((350 + 50 * unit.civInfo.getEraNumber()) * unit.civInfo.gameInfo.gameParameters.gameSpeed.modifier).toInt()
                             if (unit.civInfo.hasUnique("Double gold from Great Merchant trade missions"))
                                 goldEarned *= 2
-                            unit.civInfo.gold += goldEarned
+                            unit.civInfo.addGold(goldEarned)
                             tile.owningCity!!.civInfo.getDiplomacyManager(unit.civInfo).influence += influenceEarned
                             unit.civInfo.addNotification("Your trade mission to [${tile.owningCity!!.civInfo}] has earned you [${goldEarned}] gold and [$influenceEarned] influence!",
                                     tile.owningCity!!.civInfo.civName, NotificationIcon.Gold, NotificationIcon.Culture)
@@ -428,7 +428,7 @@ object UnitActions {
         val cityWithMausoleum = civInfo.cities.firstOrNull { it.containsBuildingUnique(uniqueText) }
                 ?: return
         val goldEarned = (100 * civInfo.gameInfo.gameParameters.gameSpeed.modifier).toInt()
-        civInfo.gold += goldEarned
+        civInfo.addGold(goldEarned)
 
         val mausoleum = cityWithMausoleum.cityConstructions.getBuiltBuildings().first { it.uniques.contains(uniqueText) }
         civInfo.addNotification("[${mausoleum.name}] has provided [$goldEarned] Gold!", cityWithMausoleum.location, NotificationIcon.Gold)