From 86bbf54cc03c37c358d2b1092967f1b0178b7cab Mon Sep 17 00:00:00 2001
From: SomeTroglodyte <63000004+SomeTroglodyte@users.noreply.github.com>
Date: Tue, 14 Sep 2021 23:34:20 +0200
Subject: [PATCH] Civilopedia quickie: Units show other direction of upgrade
 path (#5209)

* Civilopedia quickie: Units show other direction of upgrade path

* Civilopedia quickie: Units show other direction of upgrade path - spacing
---
 .../jsons/translations/template.properties     |  2 ++
 .../com/unciv/models/ruleset/unit/BaseUnit.kt  | 18 ++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/android/assets/jsons/translations/template.properties b/android/assets/jsons/translations/template.properties
index e1c334e74e..43ac28a20d 100644
--- a/android/assets/jsons/translations/template.properties
+++ b/android/assets/jsons/translations/template.properties
@@ -953,6 +953,8 @@ Tutorials =
 Cost = 
 May contain [listOfResources] = 
 May contain: = 
+Can upgrade from [unit] = 
+Can upgrade from: = 
 Upgrades to [upgradedUnit] = 
 Obsolete with [obsoleteTech] = 
 Occurs on [listOfTerrains] = 
diff --git a/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt b/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt
index c67556c93e..91f62c567f 100644
--- a/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt
+++ b/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt
@@ -154,6 +154,24 @@ class BaseUnit : INamed, INonPerpetualConstruction, ICivilopediaText {
 
         if (requiredTech != null || upgradesTo != null || obsoleteTech != null) textList += FormattedLine()
         if (requiredTech != null) textList += FormattedLine("Required tech: [$requiredTech]", link="Technology/$requiredTech")
+
+        val canUpgradeFrom = ruleset.units
+            .filterValues {
+                (it.upgradesTo == name || it.upgradesTo != null && it.upgradesTo == replaces)
+                && (it.uniqueTo == uniqueTo || it.uniqueTo == null)
+            }.keys
+        if (canUpgradeFrom.isNotEmpty()) {
+            if (canUpgradeFrom.size == 1)
+                textList += FormattedLine("Can upgrade from [${canUpgradeFrom.first()}]", link = "Unit/${canUpgradeFrom.first()}")
+            else {
+                textList += FormattedLine()
+                textList += FormattedLine("Can upgrade from:")
+                for (unitName in canUpgradeFrom.sorted())
+                    textList += FormattedLine(unitName, indent = 2, link = "Unit/$unitName")
+                textList += FormattedLine()
+            }
+        }
+
         if (upgradesTo != null) textList += FormattedLine("Upgrades to [$upgradesTo]", link="Unit/$upgradesTo")
         if (obsoleteTech != null) textList += FormattedLine("Obsolete with [$obsoleteTech]", link="Technology/$obsoleteTech")