Fix #54: Add tooltip to empty upgrade slots

Author: Technici4n

src/client/java/dev/technici4n/moderndynamics/client/screen/AttachedIoScreen.java

@@ -30,6 +30,7 @@
 import dev.technici4n.moderndynamics.util.MdId;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 import java.util.function.Consumer;
 import net.minecraft.ChatFormatting;
 import net.minecraft.client.gui.components.AbstractWidget;
@@ -126,6 +127,19 @@ public void render(PoseStack poseStack, int mouseX, int mouseY, float partialTic
         super.render(poseStack, mouseX, mouseY, partialTick);
     }
 
+    @Override
+    protected void renderTooltip(PoseStack poseStack, int mouseX, int mouseY) {
+        if (hoveredSlot != null && !hoveredSlot.hasItem() && hoveredSlot instanceof UpgradeSlot) {
+            renderTooltip(poseStack, List.of(
+                    Component.translatable("gui.moderndynamics.tooltip.slot.upgrade"),
+                    Component.translatable("gui.moderndynamics.tooltip.slot.upgrade_desc1").withStyle(ChatFormatting.GOLD),
+                    Component.translatable("gui.moderndynamics.tooltip.slot.upgrade_desc2").withStyle(ChatFormatting.GOLD)),
+                    Optional.empty(), mouseX, mouseY);
+        } else {
+            super.renderTooltip(poseStack, mouseX, mouseY);
+        }
+    }
+
     @Override
     public void renderSlot(PoseStack poseStack, Slot slot) {
         // Skip disabled slots

src/main/resources/assets/moderndynamics/lang/en_us.json

@@ -30,7 +30,7 @@
     "gui.moderndynamics.setting.routing_mode.random": "Random",
     "gui.moderndynamics.setting.routing_mode.round_robin": "Round-Robin",
     "gui.moderndynamics.tooltip.advanced_behavior_available": "Available",
-    "gui.moderndynamics.tooltip.attachment_upgrades": "Press U in EMI/JEI/REI to view upgrades",
+    "gui.moderndynamics.tooltip.attachment_upgrades": "Press U in EMI/JEI/REI to view upgrades.",
     "gui.moderndynamics.tooltip.filter_damage": "Damage",
     "gui.moderndynamics.tooltip.filter_inversion": "Invert",
     "gui.moderndynamics.tooltip.filter_mod": "Mod",
@@ -44,6 +44,9 @@
     "gui.moderndynamics.tooltip.oversending_mode": "Oversending Mode",
     "gui.moderndynamics.tooltip.requires_advanced_behavior": "Requires Advanced Behavior Upgrade",
     "gui.moderndynamics.tooltip.routing_mode": "Routing Mode",
+    "gui.moderndynamics.tooltip.slot.upgrade": "Upgrade Slot",
+    "gui.moderndynamics.tooltip.slot.upgrade_desc1": "Press U on an Attractor/Extractor/Filter",
+    "gui.moderndynamics.tooltip.slot.upgrade_desc2": "in EMI/JEI/REI to view available upgrades.",
     "gui.moderndynamics.tooltip.upgrade_addFilterSlots": "Filter Slots: %s",
     "gui.moderndynamics.tooltip.upgrade_addFluidTransfer": "Base Fluid Transfer: %s",
     "gui.moderndynamics.tooltip.upgrade_addItemCount": "Max Moved Items: %s",