    001package net.minecraft.block;
    002
    003import java.util.List;
    004import java.util.Random;
    005import net.minecraft.entity.Entity;
    006import net.minecraft.entity.item.EntityMinecart;
    007import net.minecraft.util.AxisAlignedBB;
    008import net.minecraft.world.IBlockAccess;
    009import net.minecraft.world.World;
    010
    011public class BlockDetectorRail extends BlockRail
    012{
    013    public BlockDetectorRail(int par1, int par2)
    014    {
    015        super(par1, par2, true);
    016        this.setTickRandomly(true);
    017    }
    018
    019    /**
    020     * How many world ticks before ticking
    021     */
    022    public int tickRate()
    023    {
    024        return 20;
    025    }
    026
    027    /**
    028     * Can this block provide power. Only wire currently seems to have this change based on its state.
    029     */
    030    public boolean canProvidePower()
    031    {
    032        return true;
    033    }
    034
    035    /**
    036     * Triggered whenever an entity collides with this block (enters into the block). Args: world, x, y, z, entity
    037     */
    038    public void onEntityCollidedWithBlock(World par1World, int par2, int par3, int par4, Entity par5Entity)
    039    {
    040        if (!par1World.isRemote)
    041        {
    042            int var6 = par1World.getBlockMetadata(par2, par3, par4);
    043
    044            if ((var6 & 8) == 0)
    045            {
    046                this.setStateIfMinecartInteractsWithRail(par1World, par2, par3, par4, var6);
    047            }
    048        }
    049    }
    050
    051    /**
    052     * Ticks the block if it's been scheduled
    053     */
    054    public void updateTick(World par1World, int par2, int par3, int par4, Random par5Random)
    055    {
    056        if (!par1World.isRemote)
    057        {
    058            int var6 = par1World.getBlockMetadata(par2, par3, par4);
    059
    060            if ((var6 & 8) != 0)
    061            {
    062                this.setStateIfMinecartInteractsWithRail(par1World, par2, par3, par4, var6);
    063            }
    064        }
    065    }
    066
    067    /**
    068     * Returns true if the block is emitting indirect/weak redstone power on the specified side. If isBlockNormalCube
    069     * returns true, standard redstone propagation rules will apply instead and this will not be called. Args: World, X,
    070     * Y, Z, side. Note that the side is reversed - eg it is 1 (up) when checking the bottom of the block.
    071     */
    072    public boolean isProvidingWeakPower(IBlockAccess par1IBlockAccess, int par2, int par3, int par4, int par5)
    073    {
    074        return (par1IBlockAccess.getBlockMetadata(par2, par3, par4) & 8) != 0;
    075    }
    076
    077    /**
    078     * Returns true if the block is emitting direct/strong redstone power on the specified side. Args: World, X, Y, Z,
    079     * side. Note that the side is reversed - eg it is 1 (up) when checking the bottom of the block.
    080     */
    081    public boolean isProvidingStrongPower(IBlockAccess par1IBlockAccess, int par2, int par3, int par4, int par5)
    082    {
    083        return (par1IBlockAccess.getBlockMetadata(par2, par3, par4) & 8) == 0 ? false : par5 == 1;
    084    }
    085
    086    /**
    087     * Update the detector rail power state if a minecart enter, stays or leave the block.
    088     */
    089    private void setStateIfMinecartInteractsWithRail(World par1World, int par2, int par3, int par4, int par5)
    090    {
    091        boolean var6 = (par5 & 8) != 0;
    092        boolean var7 = false;
    093        float var8 = 0.125F;
    094        List var9 = par1World.getEntitiesWithinAABB(EntityMinecart.class, AxisAlignedBB.getAABBPool().addOrModifyAABBInPool((double)((float)par2 + var8), (double)par3, (double)((float)par4 + var8), (double)((float)(par2 + 1) - var8), (double)((float)(par3 + 1) - var8), (double)((float)(par4 + 1) - var8)));
    095
    096        if (!var9.isEmpty())
    097        {
    098            var7 = true;
    099        }
    100
    101        if (var7 && !var6)
    102        {
    103            par1World.setBlockMetadataWithNotify(par2, par3, par4, par5 | 8);
    104            par1World.notifyBlocksOfNeighborChange(par2, par3, par4, this.blockID);
    105            par1World.notifyBlocksOfNeighborChange(par2, par3 - 1, par4, this.blockID);
    106            par1World.markBlockRangeForRenderUpdate(par2, par3, par4, par2, par3, par4);
    107        }
    108
    109        if (!var7 && var6)
    110        {
    111            par1World.setBlockMetadataWithNotify(par2, par3, par4, par5 & 7);
    112            par1World.notifyBlocksOfNeighborChange(par2, par3, par4, this.blockID);
    113            par1World.notifyBlocksOfNeighborChange(par2, par3 - 1, par4, this.blockID);
    114            par1World.markBlockRangeForRenderUpdate(par2, par3, par4, par2, par3, par4);
    115        }
    116
    117        if (var7)
    118        {
    119            par1World.scheduleBlockUpdate(par2, par3, par4, this.blockID, this.tickRate());
    120        }
    121    }
    122}