Paper/src/main/java/net/minecraft/server/BlockMinecartTrack.java

package net.minecraft.server;

import java.util.Random;

public class BlockMinecartTrack extends Block {

    private final boolean a;

    public static final boolean g(World world, int i, int j, int k) {
        int l = world.getTypeId(i, j, k);

        return l == Block.RAILS.id || l == Block.GOLDEN_RAIL.id || l == Block.DETECTOR_RAIL.id;
    }

    public static final boolean d(int i) {
        return i == Block.RAILS.id || i == Block.GOLDEN_RAIL.id || i == Block.DETECTOR_RAIL.id;
    }

    protected BlockMinecartTrack(int i, int j, boolean flag) {
        super(i, j, Material.ORIENTABLE);
        this.a = flag;
        this.a(0.0F, 0.0F, 0.0F, 1.0F, 0.125F, 1.0F);
    }

    public boolean i() {
        return this.a;
    }

    public AxisAlignedBB e(World world, int i, int j, int k) {
        return null;
    }

    public boolean a() {
        return false;
    }

    public MovingObjectPosition a(World world, int i, int j, int k, Vec3D vec3d, Vec3D vec3d1) {
        this.updateShape(world, i, j, k);
        return super.a(world, i, j, k, vec3d, vec3d1);
    }

    public void updateShape(IBlockAccess iblockaccess, int i, int j, int k) {
        int l = iblockaccess.getData(i, j, k);

        if (l >= 2 && l <= 5) {
            this.a(0.0F, 0.0F, 0.0F, 1.0F, 0.625F, 1.0F);
        } else {
            this.a(0.0F, 0.0F, 0.0F, 1.0F, 0.125F, 1.0F);
        }
    }

    public int a(int i, int j) {
        if (this.a) {
            if (this.id == Block.GOLDEN_RAIL.id && (j & 8) == 0) {
                return this.textureId - 16;
            }
        } else if (j >= 6) {
            return this.textureId - 16;
        }

        return this.textureId;
    }

    public boolean b() {
        return false;
    }

    public int c() {
        return 9;
    }

    public int a(Random random) {
        return 1;
    }

    public boolean canPlace(World world, int i, int j, int k) {
        return world.e(i, j - 1, k);
    }

    public void onPlace(World world, int i, int j, int k) {
        if (!world.isStatic) {
            this.a(world, i, j, k, true);
            if (this.id == Block.GOLDEN_RAIL.id) {
                // this.doPhysics(world, i, j, k, this.id); CraftBukkit - Fix issues with rails
            }
        }
    }

    public void doPhysics(World world, int i, int j, int k, int l) {
        if (!world.isStatic) {
            int i1 = world.getData(i, j, k);
            int j1 = i1;

            if (this.a) {
                j1 = i1 & 7;
            }

            boolean flag = false;

            if (!world.e(i, j - 1, k)) {
                flag = true;
            }

            if (j1 == 2 && !world.e(i + 1, j, k)) {
                flag = true;
            }

            if (j1 == 3 && !world.e(i - 1, j, k)) {
                flag = true;
            }

            if (j1 == 4 && !world.e(i, j, k - 1)) {
                flag = true;
            }

            if (j1 == 5 && !world.e(i, j, k + 1)) {
                flag = true;
            }

            if (flag) {
                this.b(world, i, j, k, world.getData(i, j, k), 0);
                world.setTypeId(i, j, k, 0);
            } else if (this.id == Block.GOLDEN_RAIL.id) {
                boolean flag1 = world.isBlockIndirectlyPowered(i, j, k);

                flag1 = flag1 || this.a(world, i, j, k, i1, true, 0) || this.a(world, i, j, k, i1, false, 0);
                boolean flag2 = false;

                if (flag1 && (i1 & 8) == 0) {
                    world.setData(i, j, k, j1 | 8);
                    flag2 = true;
                } else if (!flag1 && (i1 & 8) != 0) {
                    world.setData(i, j, k, j1);
                    flag2 = true;
                }

                if (flag2) {
                    world.applyPhysics(i, j - 1, k, this.id);
                    if (j1 == 2 || j1 == 3 || j1 == 4 || j1 == 5) {
                        world.applyPhysics(i, j + 1, k, this.id);
                    }
                }
            } else if (l > 0 && Block.byId[l].isPowerSource() && !this.a && MinecartTrackLogic.a(new MinecartTrackLogic(this, world, i, j, k)) == 3) {
                this.a(world, i, j, k, false);
            }
        }
    }

    private void a(World world, int i, int j, int k, boolean flag) {
        if (!world.isStatic) {
            (new MinecartTrackLogic(this, world, i, j, k)).a(world.isBlockIndirectlyPowered(i, j, k), flag);
        }
    }

    private boolean a(World world, int i, int j, int k, int l, boolean flag, int i1) {
        if (i1 >= 8) {
            return false;
        } else {
            int j1 = l & 7;
            boolean flag1 = true;

            switch (j1) {
            case 0:
                if (flag) {
                    ++k;
                } else {
                    --k;
                }
                break;

            case 1:
                if (flag) {
                    --i;
                } else {
                    ++i;
                }
                break;

            case 2:
                if (flag) {
                    --i;
                } else {
                    ++i;
                    ++j;
                    flag1 = false;
                }

                j1 = 1;
                break;

            case 3:
                if (flag) {
                    --i;
                    ++j;
                    flag1 = false;
                } else {
                    ++i;
                }

                j1 = 1;
                break;

            case 4:
                if (flag) {
                    ++k;
                } else {
                    --k;
                    ++j;
                    flag1 = false;
                }

                j1 = 0;
                break;

            case 5:
                if (flag) {
                    ++k;
                    ++j;
                    flag1 = false;
                } else {
                    --k;
                }

                j1 = 0;
            }

            return this.a(world, i, j, k, flag, i1, j1) ? true : flag1 && this.a(world, i, j - 1, k, flag, i1, j1);
        }
    }

    private boolean a(World world, int i, int j, int k, boolean flag, int l, int i1) {
        int j1 = world.getTypeId(i, j, k);

        if (j1 == Block.GOLDEN_RAIL.id) {
            int k1 = world.getData(i, j, k);
            int l1 = k1 & 7;

            if (i1 == 1 && (l1 == 0 || l1 == 4 || l1 == 5)) {
                return false;
            }

            if (i1 == 0 && (l1 == 1 || l1 == 2 || l1 == 3)) {
                return false;
            }

            if ((k1 & 8) != 0) {
                if (world.isBlockIndirectlyPowered(i, j, k)) {
                    return true;
                }

                return this.a(world, i, j, k, k1, flag, l + 1);
            }
        }

        return false;
    }

    public int g() {
        return 0;
    }

    static boolean a(BlockMinecartTrack blockminecarttrack) {
        return blockminecarttrack.a;
    }
}