SlightlyVanilla/src/main/java/com/thebrokenrail/slightlyvanilla/mixin/MixinRespawnAnchorBlock.java

package com.thebrokenrail.slightlyvanilla.mixin;

import com.thebrokenrail.slightlyvanilla.SlightlyVanilla;
import net.minecraft.block.RespawnAnchorBlock;
import net.minecraft.server.network.ServerPlayerEntity;
import net.minecraft.util.math.BlockPos;
import net.minecraft.world.World;
import org.spongepowered.asm.mixin.Mixin;
import org.spongepowered.asm.mixin.injection.At;
import org.spongepowered.asm.mixin.injection.Inject;
import org.spongepowered.asm.mixin.injection.Redirect;
import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;

@SuppressWarnings("unused")
@Mixin(RespawnAnchorBlock.class)
public class MixinRespawnAnchorBlock {
    @Inject(at = @At("HEAD"), method = "isNether", cancellable = true)
    private static void isNether(World world, CallbackInfoReturnable<Boolean> info) {
        if (SlightlyVanilla.getConfig().useRespawnAnchorInAnyDimension) {
            info.setReturnValue(true);
        }
    }

    @Redirect(at = @At(value = "INVOKE", target = "Lnet/minecraft/server/network/ServerPlayerEntity;getSpawnPointPosition()Lnet/minecraft/util/math/BlockPos;"), method = "onUse")
    public BlockPos getSpawnPointPosition(ServerPlayerEntity serverPlayerEntity) {
        if (SlightlyVanilla.getConfig().useRespawnAnchorInAnyDimension && serverPlayerEntity.getSpawnPointPosition() == null) {
            return new BlockPos(0, 512, 0);
        } else {
            return serverPlayerEntity.getSpawnPointPosition();
        }
    }
}