Add Transform Action for mods (#8120)

* Initial version of code

* Enable cost=0 for buttons

* Add Conditional to Transform

* Fix translation file

* Add icon
Allow other Conditionals

* Updated icon

* Add credit

* switch hotkey

* Fix icon

* Remove Conditional Costs

* Remove vestigal Stats costs for Transform

* Minor cleanup

android/assets/jsons/translations/template.properties

@@ -946,6 +946,8 @@ Add in capital =
 Add to [comment] = 
 Upgrade to [unitType] ([goldCost] gold) = 
 Upgrade to [unitType]\n([goldCost] gold, [resources]) = 
+Transform to [unitType] = 
+Transform to [unitType]\n([resources]) = 
 Found city = 
 Promote = 
 Health = 
@@ -1330,6 +1332,7 @@ Can upgrade from [unit] =
 Can upgrade from: = 
 Upgrades to [upgradedUnit] = 
 Obsolete with [obsoleteTech] = 
+Can Transform to [upgradedUnit] = 
 Occurs on [listOfTerrains] = 
 Occurs on: = 
 Placed on [terrainType] = 

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

@@ -1235,7 +1235,7 @@ class CivilizationInfo : IsPartOfGameInfoSerialization {
             Stat.Culture -> policies.storedCulture
             Stat.Science -> {
                 if (tech.currentTechnology() == null) 0
-                else tech.remainingScienceToTech(tech.currentTechnology()!!.name)
+                else tech.researchOfTech(tech.currentTechnology()!!.name)
             }
             Stat.Gold -> gold
             Stat.Faith -> religionManager.storedFaith

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

@@ -83,6 +83,8 @@ enum class UnitActionType(
         { ImageGetter.getUnitActionPortrait("Promote") }, 'o', false, UncivSound.Promote),
     Upgrade("Upgrade",
         { ImageGetter.getUnitActionPortrait("Upgrade") }, 'u', UncivSound.Upgrade),
+    Transform("Transform",
+        { ImageGetter.getUnitActionPortrait("Transform") }, 'k', UncivSound.Upgrade),
     Pillage("Pillage",
         { ImageGetter.getUnitActionPortrait("Pillage") }, 'p', false),
     Paradrop("Paradrop",

core/src/com/unciv/models/ruleset/unique/UniqueType.kt

@@ -480,7 +480,7 @@ enum class UniqueType(val text: String, vararg targets: UniqueTarget, val flags:
     CanHurryResearch("Can hurry technology research", UniqueTarget.Unit),
     CanTradeWithCityStateForGoldAndInfluence("Can undertake a trade mission with City-State, giving a large sum of gold and [amount] Influence", UniqueTarget.Unit),
 
-
+    CanTransform("Can transform to [unit]", UniqueTarget.Unit),
 
     //endregion
 

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

@@ -18,6 +18,7 @@ import com.unciv.models.UncivSound
 import com.unciv.models.UnitAction
 import com.unciv.models.UnitActionType
 import com.unciv.models.ruleset.Building
+import com.unciv.models.ruleset.unique.StateForConditionals
 import com.unciv.models.ruleset.unique.UniqueTriggerActivation
 import com.unciv.models.ruleset.unique.UniqueType
 import com.unciv.models.stats.Stat
@@ -57,6 +58,7 @@ object UnitActions {
 
         addPromoteAction(unit, actionList)
         addUnitUpgradeAction(unit, actionList)
+        addTransformAction(unit, actionList)
         addPillageAction(unit, actionList, worldScreen)
         addParadropAction(unit, actionList)
         addAirSweepAction(unit, actionList)
@@ -472,6 +474,70 @@ object UnitActions {
     fun getAncientRuinsUpgradeAction(unit: MapUnit) =
         getUpgradeAction(unit,  isFree = true, isSpecial = true)
 
+    private fun addTransformAction(
+        unit: MapUnit,
+        actionList: ArrayList<UnitAction>,
+        maxSteps: Int = Int.MAX_VALUE
+    ) {
+        val upgradeAction = getTransformAction(unit)
+        if (upgradeAction != null) actionList += upgradeAction
+    }
+
+    /**  */
+    private fun getTransformAction(
+        unit: MapUnit
+    ): ArrayList<UnitAction>? {
+        if (!unit.baseUnit().hasUnique(UniqueType.CanTransform)) return null // can't upgrade to anything
+        val unitTile = unit.getTile()
+        val civInfo = unit.civInfo
+        val transformList = ArrayList<UnitAction>()
+        for (unique in unit.baseUnit().getMatchingUniques(UniqueType.CanTransform,
+            StateForConditionals(unit = unit, civInfo = civInfo, tile = unitTile))) {
+            val upgradedUnit = civInfo.getEquivalentUnit(unique.params[0])
+            // don't show if haven't researched/is obsolete
+            if (!unit.canUpgrade(unitToUpgradeTo = upgradedUnit)) continue
+
+            // Check _new_ resource requirements
+            // Using Counter to aggregate is a bit exaggerated, but - respect the mad modder.
+            val resourceRequirementsDelta = Counter<String>()
+            for ((resource, amount) in unit.baseUnit().getResourceRequirements())
+                resourceRequirementsDelta.add(resource, -amount)
+            for ((resource, amount) in upgradedUnit.getResourceRequirements())
+                resourceRequirementsDelta.add(resource, amount)
+            val newResourceRequirementsString = resourceRequirementsDelta.entries
+                .filter { it.value > 0 }
+                .joinToString { "${it.value} {${it.key}}".tr() }
+
+            val title = if (newResourceRequirementsString.isEmpty())
+                "Transform to [${upgradedUnit.name}]"
+            else "Transform to [${upgradedUnit.name}]\n([$newResourceRequirementsString])"
+
+            transformList.add(UnitAction(UnitActionType.Transform,
+                title = title,
+                action = {
+                    unit.destroy()
+                    val newUnit = civInfo.placeUnitNearTile(unitTile.position, upgradedUnit.name)
+
+                    /** We were UNABLE to place the new unit, which means that the unit failed to upgrade!
+                     * The only known cause of this currently is "land units upgrading to water units" which fail to be placed.
+                     */
+                    if (newUnit == null) {
+                        val resurrectedUnit = civInfo.placeUnitNearTile(unitTile.position, unit.name)!!
+                        unit.copyStatisticsTo(resurrectedUnit)
+                    } else { // Managed to upgrade
+                        unit.copyStatisticsTo(newUnit)
+                        newUnit.currentMovement = 0f
+                    }
+                }.takeIf {
+                    unit.currentMovement > 0
+                            && !unit.isEmbarked()
+                            && unit.canUpgrade(unitToUpgradeTo = upgradedUnit)
+                }
+            ) )
+        }
+        return transformList
+    }
+
     private fun addBuildingImprovementsAction(unit: MapUnit, actionList: ArrayList<UnitAction>, tile: TileInfo, worldScreen: WorldScreen, unitTable: UnitTable) {
         if (!unit.hasUniqueToBuildImprovements) return
         if (unit.isEmbarked()) return

docs/Credits.md

@@ -768,6 +768,7 @@ Unless otherwise specified, all the following are from [the Noun Project](https:
 - [Trade](https://www.flaticon.com/free-icon/trade_4257019) created by Smashicons for Conduct Trade Mission
 - [Nothing](https://www.flaticon.com/free-icon/nothing_5084125) created by Freepik for Nothing construction process
 - Icon for Unique created by [vegeta1k95](https://github.com/vegeta1k95)
+- [Transform] created by letstalkaboutdune
 
 ### Main menu