From de6e3f9ec823f949ce680eba80ec2d481a622e91 Mon Sep 17 00:00:00 2001
From: Yair Morgenstern <yairm210@hotmail.com>
Date: Tue, 3 Jul 2018 16:37:20 +0300
Subject: [PATCH] All AI units that don't have a speciific target to attack
 will head towards the closest hostile city

---
 .../unciv/logic/automation/UnitAutomation.kt    | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/core/src/com/unciv/logic/automation/UnitAutomation.kt b/core/src/com/unciv/logic/automation/UnitAutomation.kt
index e764eb402c..c60a46c9be 100644
--- a/core/src/com/unciv/logic/automation/UnitAutomation.kt
+++ b/core/src/com/unciv/logic/automation/UnitAutomation.kt
@@ -1,6 +1,7 @@
 package com.unciv.logic.automation
 
 import com.unciv.UnCivGame
+import com.unciv.logic.HexMath
 import com.unciv.logic.battle.Battle
 import com.unciv.logic.battle.BattleDamage
 import com.unciv.logic.battle.MapUnitCombatant
@@ -146,6 +147,22 @@ class UnitAutomation{
             return
         }
 
+        // Focus all units without a specific target on the enemy city closest to one of our cities
+        val enemyCities = unit.civInfo.exploredTiles.map { unit.civInfo.gameInfo.tileMap[it] }
+                .filter { it.isCityCenter() && it.getOwner()!=unit.civInfo }
+        if(enemyCities.isNotEmpty() && unit.civInfo.cities.isNotEmpty()) {
+            val closestReachableEnemyCity = enemyCities
+                    .filter { unit.movementAlgs().canReach(it) }
+                    .minBy { city ->
+                        unit.civInfo.cities.map { HexMath().getDistance(city.position, it.getCenterTile().position) }.min()!!
+                    }
+            if (closestReachableEnemyCity != null) {
+                unit.movementAlgs().headTowards(closestReachableEnemyCity)
+                return
+            }
+        }
+
+
         // else, go to a random space
         randomWalk(unit)
         // if both failed, then... there aren't any reachable tiles. Which is possible.