PrettyPipes/src/main/java/de/ellpeck/prettypipes/blocks/pipe/PipeTileEntity.java

package de.ellpeck.prettypipes.blocks.pipe;

import de.ellpeck.prettypipes.PrettyPipes;
import de.ellpeck.prettypipes.Registry;
import de.ellpeck.prettypipes.items.IModule;
import de.ellpeck.prettypipes.network.PipeItem;
import net.minecraft.entity.player.PlayerEntity;
import net.minecraft.entity.player.PlayerInventory;
import net.minecraft.inventory.container.Container;
import net.minecraft.inventory.container.INamedContainerProvider;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;
import net.minecraft.nbt.CompoundNBT;
import net.minecraft.nbt.ListNBT;
import net.minecraft.profiler.IProfiler;
import net.minecraft.tileentity.ITickableTileEntity;
import net.minecraft.tileentity.TileEntity;
import net.minecraft.util.Direction;
import net.minecraft.util.math.BlockPos;
import net.minecraft.util.text.ITextComponent;
import net.minecraft.util.text.TranslationTextComponent;
import net.minecraftforge.common.util.Constants;
import net.minecraftforge.items.CapabilityItemHandler;
import net.minecraftforge.items.IItemHandler;
import net.minecraftforge.items.ItemHandlerHelper;
import net.minecraftforge.items.ItemStackHandler;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Stream;

public class PipeTileEntity extends TileEntity implements INamedContainerProvider, ITickableTileEntity {

    public final ItemStackHandler modules = new ItemStackHandler(3) {
        @Override
        public boolean isItemValid(int slot, @Nonnull ItemStack stack) {
            return stack.getItem() instanceof IModule;
        }
    };
    public final List<PipeItem> items = new ArrayList<>();

    public PipeTileEntity() {
        super(Registry.pipeTileEntity);
    }

    @Override
    public ITextComponent getDisplayName() {
        return new TranslationTextComponent("container." + PrettyPipes.ID + ".pipe");
    }

    @Nullable
    @Override
    public Container createMenu(int window, PlayerInventory inv, PlayerEntity player) {
        return new PipeContainer(Registry.pipeContainer, window, player, this);
    }

    @Override
    public CompoundNBT write(CompoundNBT compound) {
        compound.put("modules", this.modules.serializeNBT());
        ListNBT list = new ListNBT();
        for (PipeItem item : this.items)
            list.add(item.serializeNBT());
        compound.put("items", list);
        return super.write(compound);
    }

    @Override
    public void read(CompoundNBT compound) {
        this.modules.deserializeNBT(compound.getCompound("modules"));
        this.items.clear();
        ListNBT list = compound.getList("items", Constants.NBT.TAG_COMPOUND);
        for (int i = 0; i < list.size(); i++)
            this.items.add(new PipeItem(list.getCompound(i)));
        super.read(compound);
    }

    @Override
    public CompoundNBT getUpdateTag() {
        // by default, this is just writeInternal, but we
        // want to sync the current pipe items on load too
        return this.write(new CompoundNBT());
    }

    @Override
    public void tick() {
        if (!this.world.isAreaLoaded(this.pos, 1))
            return;
        IProfiler profiler = this.world.getProfiler();

        profiler.startSection("ticking_modules");
        this.streamModules().forEach(m -> m.tick(this));
        profiler.endSection();

        profiler.startSection("ticking_items");
        for (int i = this.items.size() - 1; i >= 0; i--)
            this.items.get(i).updateInPipe(this);
        profiler.endSection();
    }

    public boolean isConnected(Direction dir) {
        return this.getBlockState().get(PipeBlock.DIRECTIONS.get(dir)).isConnected();
    }

    public BlockPos getAvailableDestination(ItemStack stack) {
        if (this.streamModules().anyMatch(u -> !u.canAcceptItem(this, stack)))
            return null;
        for (Direction dir : Direction.values()) {
            IItemHandler handler = this.getItemHandler(dir);
            if (handler == null)
                continue;
            if (!ItemHandlerHelper.insertItem(handler, stack, true).isEmpty())
                continue;
            if (this.streamModules().anyMatch(u -> !u.isAvailableDestination(this, stack, handler)))
                continue;
            return this.pos.offset(dir);
        }
        return null;
    }

    public int getPriority() {
        return this.streamModules().mapToInt(u -> u.getPriority(this)).max().orElse(0);
    }

    public IItemHandler getItemHandler(Direction dir) {
        if (!this.isConnected(dir))
            return null;
        TileEntity tile = this.world.getTileEntity(this.pos.offset(dir));
        if (tile == null)
            return null;
        return tile.getCapability(CapabilityItemHandler.ITEM_HANDLER_CAPABILITY, dir.getOpposite()).orElse(null);
    }

    public boolean isConnectedInventory(Direction dir) {
        return this.getItemHandler(dir) != null;
    }

    public boolean isConnectedInventory() {
        return Arrays.stream(Direction.values()).anyMatch(this::isConnectedInventory);
    }

    private Stream<IModule> streamModules() {
        Stream.Builder<IModule> builder = Stream.builder();
        for (int i = 0; i < this.modules.getSlots(); i++) {
            ItemStack stack = this.modules.getStackInSlot(i);
            if (stack.isEmpty())
                continue;
            Item item = stack.getItem();
            if (item instanceof IModule)
                builder.accept((IModule) item);
        }
        return builder.build();
    }
}