The charge meter can measure the charge in electric carts

src/generated/resources/.cache/c622617f6fabf890a00b9275cd5f643584a8a2c8

@@ -1,2 +1,2 @@
-// 1.20.1	2023-09-10T16:28:13.344594	Languages: en_us
-3d94fe9dac885db8064e1f5978c4aaafa0026200 assets/railcraft/lang/en_us.json
+// 1.20.1	2023-09-26T11:16:14.330781	Languages: en_us
+6c90e792080e4adf933d2540dea658da1fa5b843 assets/railcraft/lang/en_us.json

src/generated/resources/assets/railcraft/lang/en_us.json

@@ -389,6 +389,7 @@
   "block.railcraft.zinc_ore": "Zinc Ore",
   "block.railcraft.zinc_silver_battery": "Zinc-Silver Battery",
   "block.railcraft.zinc_silver_battery_empty": "Zinc-Silver Empty Battery",
+  "charge_meter.railcraft.cart": "Cart -> Charge: %s FE | Draw: %s FE/t | Loss: %s FE/t",
   "charge_meter.railcraft.network": "Network -> Size: %s | Charge: %s FE | Draw: %s FE/t | MaxDraw: %s FE/t | Loss: %s FE/t | Eff: %s%%",
   "charge_meter.railcraft.node": "Node -> Draw: %s FE/t | Loss: %s FE/t",
   "charge_meter.railcraft.producer": "Supply -> Charge: %s FE | Production: %s FE/t | MaxDraw: %s FE/t | Loss: %s FE/t | Eff: %s%%",

src/main/java/mods/railcraft/Railcraft.java

@@ -5,6 +5,7 @@
 import mods.railcraft.api.charge.Charge;
 import mods.railcraft.api.core.RailcraftConstants;
 import mods.railcraft.api.fuel.FuelUtil;
+import mods.railcraft.charge.ChargeCartStorageImpl;
 import mods.railcraft.charge.ChargeProviderImpl;
 import mods.railcraft.charge.ZapEffectProviderImpl;
 import mods.railcraft.client.ClientManager;
@@ -42,6 +43,7 @@
 import mods.railcraft.world.entity.vehicle.MinecartHandler;
 import mods.railcraft.world.entity.vehicle.RollingStockImpl;
 import mods.railcraft.world.inventory.RailcraftMenuTypes;
+import mods.railcraft.world.item.ChargeMeterItem;
 import mods.railcraft.world.item.CrowbarHandler;
 import mods.railcraft.world.item.RailcraftCreativeModeTabs;
 import mods.railcraft.world.item.RailcraftItems;
@@ -63,6 +65,7 @@
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.InteractionResult;
 import net.minecraft.world.SimpleContainer;
 import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.npc.VillagerProfession;
@@ -73,6 +76,7 @@
 import net.minecraft.world.item.crafting.RecipeType;
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.common.brewing.BrewingRecipeRegistry;
+import net.minecraftforge.common.capabilities.ForgeCapabilities;
 import net.minecraftforge.common.capabilities.RegisterCapabilitiesEvent;
 import net.minecraftforge.data.event.GatherDataEvent;
 import net.minecraftforge.event.AttachCapabilitiesEvent;
@@ -266,15 +270,32 @@ public void handlePlayerTick(TickEvent.PlayerTickEvent event) {
   }
 
   @SubscribeEvent
-  public void handleMinecartInteract(PlayerInteractEvent.EntityInteract event) {
+  public void handleEntityInteract(PlayerInteractEvent.EntityInteract event) {
     if (event.getTarget() instanceof AbstractMinecart cart) {
       var player = event.getEntity();
       var hand = event.getHand();
-      event.setCanceled(this.minecartHandler.handleInteract(cart, player));
-      var crowbarActionResult = this.crowbarHandler.handleInteract(cart, player, hand);
-      if (crowbarActionResult.consumesAction()) {
-        event.setCanceled(true);
-        event.setCancellationResult(crowbarActionResult);
+      var stack = event.getItemStack();
+
+      if (!stack.isEmpty() && stack.is(RailcraftItems.CHARGE_METER.get())) {
+        player.swing(hand);
+        if (!player.level().isClientSide()) {
+          cart.getCapability(ForgeCapabilities.ENERGY)
+              .filter(ChargeCartStorageImpl.class::isInstance)
+              .map(ChargeCartStorageImpl.class::cast)
+              .ifPresent(battery -> {
+                ChargeMeterItem.sendChat(player, Translations.ChargeMeter.CART,
+                    battery.getEnergyStored(), battery.getDraw(), battery.getLosses());
+                event.setCanceled(true);
+                event.setCancellationResult(InteractionResult.SUCCESS);
+              });
+        }
+      } else {
+        event.setCanceled(this.minecartHandler.handleInteract(cart, player));
+        var crowbarActionResult = this.crowbarHandler.handleInteract(cart, player, hand);
+        if (crowbarActionResult.consumesAction()) {
+          event.setCanceled(true);
+          event.setCancellationResult(crowbarActionResult);
+        }
       }
     }
   }

src/main/java/mods/railcraft/Translations.java

@@ -579,6 +579,7 @@ public static class RoutingTable {
 
   public static class ChargeMeter {
     public static final String START = makeKey("charge_meter", "start");
+    public static final String CART = makeKey("charge_meter", "cart");
     public static final String NETWORK = makeKey("charge_meter", "network");
     public static final String NODE = makeKey("charge_meter", "node");
     public static final String PRODUCER = makeKey("charge_meter", "producer");

src/main/java/mods/railcraft/charge/ChargeCartStorageImpl.java

@@ -15,20 +15,15 @@ public class ChargeCartStorageImpl extends EnergyStorage implements ChargeCartSt
 
   protected static final Random RANDOM = new Random();
   private static final int DRAW_INTERVAL = 8;
-  protected final float lossPerTick;
-  protected double draw;
-  protected int clock = RANDOM.nextInt();
-  protected int drewFromTrack;
-
-  public ChargeCartStorageImpl() {
-    this(5000, 0);
-  }
+  protected final int lossPerTick;
+  protected double draw, chargeDrawnThisTick;
+  protected int drewFromTrack, clock = RANDOM.nextInt(0, DRAW_INTERVAL);
 
   public ChargeCartStorageImpl(int capacity) {
     this(capacity, 0);
   }
 
-  public ChargeCartStorageImpl(int capacity, float lossPerTick) {
+  public ChargeCartStorageImpl(int capacity, int lossPerTick) {
     super(capacity);
     this.lossPerTick = lossPerTick;
   }
@@ -61,7 +56,8 @@ public void tick(AbstractMinecart owner) {
     clock++;
     removeLosses();
 
-    draw = (draw * 24.0) / 25.0;
+    this.draw = (this.draw * 24.0 + this.chargeDrawnThisTick) / 25.0;
+    this.chargeDrawnThisTick = 0;
 
     if (drewFromTrack > 0) {
       drewFromTrack--;
@@ -79,17 +75,26 @@ public void tick(AbstractMinecart owner) {
   @Override
   public void tickOnTrack(AbstractMinecart owner, BlockPos pos) {
     if (!owner.level().isClientSide() && needsCharging()) {
-      double drawnFromTrack = Charge.distribution
+      int drawnFromTrack = Charge.distribution
           .network((ServerLevel) owner.level())
           .access(pos)
           .removeCharge(capacity - energy, false);
-      if (drawnFromTrack > 0.0) {
+      if (drawnFromTrack > 0) {
         drewFromTrack = DRAW_INTERVAL * 4;
       }
       energy += drawnFromTrack;
     }
   }
 
+  @Override
+  public int extractEnergy(int maxExtract, boolean simulate) {
+    int extracted = super.extractEnergy(maxExtract, simulate);
+    if (!simulate) {
+      this.chargeDrawnThisTick += extracted;
+    }
+    return extracted;
+  }
+
   private boolean needsCharging() {
     return this.energy < this.capacity;
   }

src/main/java/mods/railcraft/data/RailcraftLanguageProvider.java

@@ -1199,6 +1199,8 @@ private void routingTableTranslations() {
 
   private void chargeMeterTranslations() {
     this.add(Translations.ChargeMeter.START, "Recording data over %s seconds...");
+    this.add(Translations.ChargeMeter.CART, """
+        Cart -> Charge: %s FE | Draw: %s FE/t | Loss: %s FE/t""");
     this.add(Translations.ChargeMeter.NETWORK, """
         Network -> Size: %s | Charge: %s FE | Draw: %s FE/t | MaxDraw: %s FE/t | Loss: %s FE/t | \
         Eff: %s%%""");

src/main/java/mods/railcraft/network/NetworkChannel.java

@@ -36,7 +36,7 @@
  */
 public enum NetworkChannel {
 
-  GAME {
+  GAME("game") {
     @Override
     public void registerMessages(SimpleChannel simpleChannel) {
       simpleChannel
@@ -170,25 +170,19 @@ public void registerMessages(SimpleChannel simpleChannel) {
     }
   };
 
-  /**
-   * Network protocol version.
-   */
-  private static final String NETWORK_VERSION = "1";
   /**
    * Prevents re-registering messages.
    */
   private static boolean REGISTERED;
-  /**
-   * Simple channel.
-   */
   private final SimpleChannel simpleChannel;
 
-  NetworkChannel() {
+  NetworkChannel(String name) {
+    var networkVersion = "1";
     this.simpleChannel = NetworkRegistry.ChannelBuilder
-        .named(Railcraft.rl("game"))
-        .clientAcceptedVersions(NETWORK_VERSION::equals)
-        .serverAcceptedVersions(NETWORK_VERSION::equals)
-        .networkProtocolVersion(() -> NETWORK_VERSION)
+        .named(Railcraft.rl(name))
+        .clientAcceptedVersions(networkVersion::equals)
+        .serverAcceptedVersions(networkVersion::equals)
+        .networkProtocolVersion(() -> networkVersion)
         .simpleChannel();
   }
 

src/main/java/mods/railcraft/world/entity/vehicle/locomotive/ElectricLocomotive.java

@@ -26,6 +26,9 @@
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.block.state.BlockState;
+import net.minecraftforge.common.capabilities.Capability;
+import net.minecraftforge.common.capabilities.ForgeCapabilities;
+import net.minecraftforge.common.util.LazyOptional;
 import net.minecraftforge.energy.IEnergyStorage;
 
 public class ElectricLocomotive extends Locomotive implements WorldlyContainer {
@@ -46,14 +49,17 @@ public class ElectricLocomotive extends Locomotive implements WorldlyContainer {
       new ContainerMapper(this, SLOT_TICKET, 2).ignoreItemChecks();
 
   private ChargeCartStorageImpl cartStorage = new ChargeCartStorageImpl(MAX_CHARGE);
+  private final LazyOptional<IEnergyStorage> energyHandler;
 
   public ElectricLocomotive(EntityType<?> type, Level level) {
     super(type, level);
+    this.energyHandler = LazyOptional.of(() -> this.cartStorage);
   }
 
   public ElectricLocomotive(ItemStack itemStack, double x, double y, double z,
       ServerLevel serverLevel) {
     super(itemStack, RailcraftEntityTypes.ELECTRIC_LOCOMOTIVE.get(), x, y, z, serverLevel);
+    this.energyHandler = LazyOptional.of(() -> this.cartStorage);
   }
 
   @Override
@@ -185,6 +191,13 @@ public ItemStack getPickResult() {
     return itemStack;
   }
 
+  @Override
+  public <T> LazyOptional<T> getCapability(Capability<T> capability, @Nullable Direction facing) {
+    return ForgeCapabilities.ENERGY == capability
+        ? this.energyHandler.cast()
+        : super.getCapability(capability, facing);
+  }
+
   @Override
   protected AbstractContainerMenu createMenu(int id, Inventory playerInventory) {
     return new ElectricLocomotiveMenu(id, playerInventory, this);

src/main/java/mods/railcraft/world/item/ChargeMeterItem.java

@@ -63,7 +63,7 @@ public InteractionResult useOn(UseOnContext context) {
     return returnValue;
   }
 
-  private void sendChat(Player player, String translation, Object... args) {
+  public static void sendChat(Player player, String translation, Object... args) {
     for (int i = 0; i < args.length; i++) {
       if (args[i] instanceof Double doubleArg)
         args[i] = HumanReadableNumberFormatter.format(doubleArg);