AutoPlacement.java

/* SPDX-License-Identifier: MIT */

package me.recursiveg.automation;

import net.minecraft.client.Minecraft;
import net.minecraft.client.multiplayer.MultiPlayerGameMode;
import net.minecraft.client.player.LocalPlayer;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.core.NonNullList;
import net.minecraft.world.InteractionHand;
import net.minecraft.world.inventory.ClickType;
import net.minecraft.world.item.BlockItem;
import net.minecraft.world.item.Item;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.phys.BlockHitResult;
import net.minecraft.world.phys.Vec3;
import net.minecraftforge.event.TickEvent;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.LogicalSide;

import java.util.Map;

public class AutoPlacement implements IAutomation {
    private boolean enabled = false;
    private int toolSlot = 0;
    private Block used_material = null;
    private BlockPos player_block_pos = null;
    private int blockY;
    private double blockOffsetY; // 0-1


    @Override
    public void enable() {
        LocalPlayer p = Minecraft.getInstance().player;
        if (p == null) return;

        double offY = p.getY() % 1.0;
        if (offY < 0.9 && offY > 0.1) {
            // Standing on not complete block
            blockY = (int) Math.floor(p.getY());
            blockOffsetY = 0.3;
        } else {
            // Standing on complete block
            blockY = (int) p.getY() - 1;
            blockOffsetY = 0.7;
        }

        toolSlot = p.getInventory().selected;
        Item item = p.getInventory().getSelected().getItem();
        if (item instanceof BlockItem bi) {
            used_material = bi.getBlock();
            player_block_pos = p.blockPosition();
            enabled = true;
            AutomationMod.msg("AutoPlacement enabled: %s, blockY: %d, blockOffsetY: %f", enabled, blockY, blockOffsetY);
        }
    }

    @Override
    public void disable() {
        enabled = false;
        AutomationMod.msg("AutoPlacement enabled: %s", enabled);
    }

    @Override
    public boolean isEnabled() {
        return enabled;
    }

    @Override
    public Map<String, String> getOptions() {
        return Map.of("enabled", "ro bool:" + enabled,
                "blockY", "ro int:" + blockY,
                "blockOffsetY", "ro double:" + blockOffsetY);
    }

    @Override
    public void setOption(String op, String val) {
        AutomationMod.msg("AutoPlacement has no options");
    }

    @SubscribeEvent
    public void onTick(TickEvent.PlayerTickEvent e) {
        if (enabled && e.side == LogicalSide.CLIENT && e.player != null && e.player == Minecraft.getInstance().player) {
            if (e.player.getInventory().selected != toolSlot) {
                enabled = false;
                AutomationMod.msg("Tool switched. AutoPlacement disabled");
                return;
            }
            if (e.player.blockPosition().equals(player_block_pos)) return;
            player_block_pos = e.player.blockPosition();
            if (e.player.getInventory().getSelected().isEmpty()) {
                boolean success = tryFillItemInHand(Minecraft.getInstance().player);
                if (!success) {
                    enabled = false;
                    AutomationMod.msg("Item used up! AutoPlacement disabled");
                }
            }

            if (!tryPlacement(Minecraft.getInstance().player)) {
                enabled = false;
                AutomationMod.msg("Place Fail! AutoPlacement disabled");
            }
        }
    }

    public static void moveInventoryItem(int srcIdx, int dstIdx) {
        LocalPlayer p = Minecraft.getInstance().player;
        if (p == null) return;
        NonNullList<ItemStack> a = p.getInventory().items;
        MultiPlayerGameMode gm = Minecraft.getInstance().gameMode;
        if (gm == null) return;
        if (a.get(srcIdx).isEmpty()) return;

        if (a.get(dstIdx).isEmpty()) {
            gm.handleInventoryMouseClick(
                    /*containerId=*/0,
                    /*slotNum=*/srcIdx < 9 ? srcIdx + 36 : srcIdx,
                    /*buttonNum=*/0,
                    ClickType.PICKUP,
                    p);
            gm.handleInventoryMouseClick(
                    /*containerId=*/0,
                    /*slotNum=*/dstIdx < 9 ? dstIdx + 36 : dstIdx,
                    /*buttonNum=*/0,
                    ClickType.PICKUP,
                    p);
        } else {
            gm.handleInventoryMouseClick(
                    /*containerId=*/0,
                    /*slotNum=*/srcIdx < 9 ? srcIdx + 36 : srcIdx,
                    /*buttonNum=*/0,
                    ClickType.PICKUP,
                    p);
            gm.handleInventoryMouseClick(
                    /*containerId=*/0,
                    /*slotNum=*/dstIdx < 9 ? dstIdx + 36 : dstIdx,
                    /*buttonNum=*/0,
                    ClickType.PICKUP,
                    p);
            gm.handleInventoryMouseClick(
                    /*containerId=*/0,
                    /*slotNum=*/srcIdx < 9 ? srcIdx + 36 : srcIdx,
                    /*buttonNum=*/0,
                    ClickType.PICKUP,
                    p);
        }
    }

    // return true if success
    private boolean tryFillItemInHand(LocalPlayer p) {
        ItemStack itemStack = p.getItemInHand(InteractionHand.MAIN_HAND);
        if (!itemStack.isEmpty()) return true;
        if (used_material == null) return false;
        ItemStack expectingItem = new ItemStack(used_material);

        int supplmentIdx = -1;
        NonNullList<ItemStack> inv = p.getInventory().items;
        for (int idx = 0; idx < 36; ++idx) {
            ItemStack s = inv.get(idx);
            if (s.getItem() == expectingItem.getItem() &&
                    s.getDamageValue() == expectingItem.getDamageValue() &&
                    !s.hasTag()) {
                supplmentIdx = idx;
                break;
            }
        }
        if (supplmentIdx < 0) return false;
        moveInventoryItem(supplmentIdx, p.getInventory().selected);
        return true;
    }

    static BlockHitResult getHitResult(BlockPos block, Direction face, double blockOffsetY) {
        // New block will be placed on `face` of `block`.
        Vec3 hit = switch (face) {
            case UP -> new Vec3(block.getX() + 0.5, block.getY() + 1, block.getZ() + 0.5);
            case DOWN -> new Vec3(block.getX() + 0.5, block.getY(), block.getZ() + 0.5);
            case EAST -> new Vec3(block.getX() + 1, block.getY() + blockOffsetY, block.getZ() + 0.5);
            case SOUTH -> new Vec3(block.getX() + 0.5, block.getY() + blockOffsetY, block.getZ() + 1);
            case WEST -> new Vec3(block.getX(), block.getY() + blockOffsetY, block.getZ() + 0.5);
            case NORTH -> new Vec3(block.getX() + 0.5, block.getY() + blockOffsetY, block.getZ());
        };

        return new BlockHitResult(hit, face, block, false);
    }

    public boolean tryPlacement(LocalPlayer p) {
        BlockPos blockStandingOn = player_block_pos.atY(blockY);
        Direction d = Direction.fromYRot(p.getYRot());
        BlockPos blockWillPlaceOn = blockStandingOn.relative(d);
        BlockState blockToBeReplaced = p.level.getBlockState(blockWillPlaceOn);
        if (blockToBeReplaced.isAir() || blockToBeReplaced.getBlock() == Blocks.WATER ||
                blockToBeReplaced.getBlock() == Blocks.LAVA) {
            Minecraft.getInstance().gameMode.useItemOn(p, p.clientLevel, InteractionHand.MAIN_HAND,
                    getHitResult(blockStandingOn, d, blockOffsetY));
        }
        return true;
    }
}