Added religion city counters and spread of religion between cities - none of this is yet user-visible

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

@@ -6,6 +6,7 @@ import com.unciv.logic.civilization.diplomacy.DiplomacyFlags
 import com.unciv.logic.map.RoadStatus
 import com.unciv.logic.map.TileInfo
 import com.unciv.logic.map.TileMap
+import com.unciv.models.Counter
 import com.unciv.models.ruleset.tile.ResourceSupplyList
 import com.unciv.models.ruleset.tile.ResourceType
 import com.unciv.models.ruleset.unit.BaseUnit
@@ -46,6 +47,7 @@ class CityInfo {
     var health = 200
     var resistanceCounter = 0
 
+    var religion = CityInfoReligionManager()
     var population = PopulationManager()
     var cityConstructions = CityConstructions()
     var expansion = CityExpansionManager()
@@ -149,6 +151,7 @@ class CityInfo {
         toReturn.turnAcquired = turnAcquired
         toReturn.isPuppet = isPuppet
         toReturn.isOriginalCapital = isOriginalCapital
+        toReturn.religion = CityInfoReligionManager().apply { putAll(religion) }
         return toReturn
     }
 
@@ -315,6 +318,7 @@ class CityInfo {
         cityStats.cityInfo = this
         cityConstructions.cityInfo = this
         cityConstructions.setTransients()
+        religion.cityInfo = this
     }
 
     fun startTurn() {
@@ -365,6 +369,8 @@ class CityInfo {
             }
         } else population.nextTurn(foodForNextTurn())
 
+        if (getRuleset().hasReligion()) religion.getAffectedBySurroundingCities()
+
         if (this in civInfo.cities) { // city was not destroyed
             health = min(health + 20, getMaxHealth())
             population.unassignExtraPopulation()
@@ -476,3 +482,47 @@ class CityInfo {
     //endregion
 }
 
+class CityInfoReligionManager: Counter<String>(){
+    @Transient
+    lateinit var cityInfo: CityInfo
+
+    fun getNumberOfFollowers(): Counter<String> {
+        val totalInfluence = values.sum()
+        val population = cityInfo.population.population
+        if (totalInfluence > 100 * population) {
+            val toReturn = Counter<String>()
+            for ((key, value) in this)
+                if (value > 100)
+                    toReturn.add(key, value / 100)
+            return toReturn
+        }
+
+        val toReturn = Counter<String>()
+
+        for ((key, value) in this) {
+            val percentage = value.toFloat() / totalInfluence
+            val relativePopulation = (percentage * population).roundToInt()
+            toReturn.add(key, relativePopulation)
+        }
+        return toReturn
+    }
+
+    fun getMajorityReligion():String? {
+        val followersPerReligion = getNumberOfFollowers()
+        if (followersPerReligion.isEmpty()) return null
+        val religionWithMaxFollowers = followersPerReligion.maxByOrNull { it.value }!!
+        if (religionWithMaxFollowers.value >= cityInfo.population.population) return religionWithMaxFollowers.key
+        else return null
+    }
+
+    fun getAffectedBySurroundingCities() {
+        val allCitiesWithin10Tiles = cityInfo.civInfo.gameInfo.civilizations.asSequence().flatMap { it.cities }
+                .filter { it != cityInfo && it.getCenterTile().aerialDistanceTo(cityInfo.getCenterTile()) <= 10 }
+        for (city in allCitiesWithin10Tiles) {
+            val majorityReligionOfCity = city.religion.getMajorityReligion()
+            if (majorityReligionOfCity == null) continue
+            else add(majorityReligionOfCity, 6) // todo - when holy cities are implemented, *5
+        }
+    }
+}
+

core/src/com/unciv/models/Counter.kt

@@ -2,7 +2,7 @@ package com.unciv.models
 
 import java.util.*
 
-class Counter<K> : LinkedHashMap<K, Int>() {
+open class Counter<K> : LinkedHashMap<K, Int>() {
 
     override operator fun get(key: K): Int? { // don't return null if empty
         if (containsKey(key))