From e4d72cefaa5737bf1d16794151c5fbbd877230ab Mon Sep 17 00:00:00 2001
From: Tulio Leao <tupaschoal@gmail.com>
Date: Fri, 2 Oct 2020 00:34:54 -0300
Subject: [PATCH] Fix #5904: Empty errors on tile inspector base height change

---
 data/language/en-GB.txt               |  3 +++
 distribution/changelog.txt            |  1 +
 src/openrct2/localisation/StringIds.h |  4 ++++
 src/openrct2/world/TileInspector.cpp  | 33 +++++++++++++++++++++------
 4 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/data/language/en-GB.txt b/data/language/en-GB.txt
index 6a73a1ada2..8e8dd3610f 100644
--- a/data/language/en-GB.txt
+++ b/data/language/en-GB.txt
@@ -3642,6 +3642,9 @@ STR_6383    :Open download page
 STR_6384    :Snow
 STR_6385    :Heavy Snow
 STR_6386    :Blizzard
+STR_6387    :Can't lower element here...
+STR_6388    :Can't raise element here...
+STR_6389    :No clearance
 
 #############
 # Scenarios #
diff --git a/distribution/changelog.txt b/distribution/changelog.txt
index 812c3f5ee1..da944c4306 100644
--- a/distribution/changelog.txt
+++ b/distribution/changelog.txt
@@ -3,6 +3,7 @@
 - Feature: [#12999] .sea (RCT Classic) scenarios are now listed in the “New Scenario” dialog.
 - Feature: [#13000] objective_options command for console.
 - Fix: [#3200] Close Construction window upon selecting vehicle page.
+- Fix: [#5904] Empty errors on tile inspector base height change.
 - Fix: [#8015] RCT2 files are not found when put into the OpenRCT2 folder.
 - Fix: [#8957] Error title missing when building with insufficient funds
 - Fix: [#13021] Mowed grass and weeds don't show up in extra zoom levels.
diff --git a/src/openrct2/localisation/StringIds.h b/src/openrct2/localisation/StringIds.h
index 741c828cf4..843bfce007 100644
--- a/src/openrct2/localisation/StringIds.h
+++ b/src/openrct2/localisation/StringIds.h
@@ -3887,6 +3887,10 @@ enum
     STR_HEAVY_SNOW = 6385,
     STR_BLIZZARD = 6386,
 
+    STR_CANT_LOWER_ELEMENT_HERE = 6387,
+    STR_CANT_RAISE_ELEMENT_HERE = 6388,
+    STR_NO_CLEARANCE = 6389,
+
     // Have to include resource strings (from scenarios and objects) for the time being now that language is partially working
     /* MAX_STR_COUNT = 32768 */ // MAX_STR_COUNT - upper limit for number of strings, not the current count strings
 };
diff --git a/src/openrct2/world/TileInspector.cpp b/src/openrct2/world/TileInspector.cpp
index ca380e402d..8099d2b512 100644
--- a/src/openrct2/world/TileInspector.cpp
+++ b/src/openrct2/world/TileInspector.cpp
@@ -474,6 +474,29 @@ GameActionResult::Ptr tile_inspector_sort_elements_at(const CoordsXY& loc, bool
     return std::make_unique<GameActionResult>();
 }
 
+static GameActionResult::Ptr ValidateTileHeight(TileElement* const tileElement, int8_t heightOffset)
+{
+    int16_t newBaseHeight = static_cast<int16_t>(tileElement->base_height + heightOffset);
+    int16_t newClearanceHeight = static_cast<int16_t>(tileElement->clearance_height + heightOffset);
+    if (newBaseHeight < 0)
+    {
+        return std::make_unique<GameActionResult>(GA_ERROR::TOO_LOW, STR_CANT_LOWER_ELEMENT_HERE, STR_TOO_LOW);
+    }
+    else if (newBaseHeight > MAX_ELEMENT_HEIGHT)
+    {
+        return std::make_unique<GameActionResult>(GA_ERROR::TOO_HIGH, STR_CANT_RAISE_ELEMENT_HERE, STR_TOO_HIGH);
+    }
+    else if (newClearanceHeight < 0)
+    {
+        return std::make_unique<GameActionResult>(GA_ERROR::NO_CLEARANCE, STR_CANT_LOWER_ELEMENT_HERE, STR_NO_CLEARANCE);
+    }
+    else if (newClearanceHeight > MAX_ELEMENT_HEIGHT)
+    {
+        return std::make_unique<GameActionResult>(GA_ERROR::NO_CLEARANCE, STR_CANT_RAISE_ELEMENT_HERE, STR_NO_CLEARANCE);
+    }
+    return std::make_unique<GameActionResult>();
+}
+
 GameActionResult::Ptr tile_inspector_any_base_height_offset(
     const CoordsXY& loc, int16_t elementIndex, int8_t heightOffset, bool isExecuting)
 {
@@ -481,13 +504,9 @@ GameActionResult::Ptr tile_inspector_any_base_height_offset(
     if (tileElement == nullptr)
         return std::make_unique<GameActionResult>(GA_ERROR::UNKNOWN, STR_NONE);
 
-    int16_t newBaseHeight = static_cast<int16_t>(tileElement->base_height + heightOffset);
-    int16_t newClearanceHeight = static_cast<int16_t>(tileElement->clearance_height + heightOffset);
-    if (newBaseHeight < 0 || newBaseHeight > MAX_ELEMENT_HEIGHT || newClearanceHeight < 0
-        || newClearanceHeight > MAX_ELEMENT_HEIGHT)
-    {
-        return std::make_unique<GameActionResult>(GA_ERROR::UNKNOWN, STR_NONE);
-    }
+    auto heightValidationResult = ValidateTileHeight(tileElement, heightOffset);
+    if (heightValidationResult->Error != GA_ERROR::OK)
+        return heightValidationResult;
 
     if (isExecuting)
     {