package net.minecraftforge.fluids;

import java.util.Random;

import net.minecraft.block.Block;
import net.minecraft.block.material.Material;
import net.minecraft.world.IBlockAccess;
import net.minecraft.world.World;

/**
 * This is a cellular-automata based finite fluid block implementation.
 * 
 * It is highly recommended that you use/extend this class for finite fluid blocks.
 * 
 * @author OvermindDL1, KingLemming
 * 
 */
public class BlockFluidFinite extends BlockFluidBase {

    public BlockFluidFinite(int id, Fluid fluid, Material material) {

        super(id, fluid, material);
    }

    @Override
    public int getQuantaValue(IBlockAccess world, int x, int y, int z) {

        if (world.getBlockId(x, y, z) == 0) {
            return 0;
        }
        if (world.getBlockId(x, y, z) != blockID) {
            return -1;
        }
        int quantaRemaining = world.getBlockMetadata(x, y, z) + 1;
        return quantaRemaining;
    }

    @Override
    public boolean canCollideCheck(int meta, boolean fullHit) {

        return fullHit && meta == quantaPerBlock - 1;
    }

    @Override
    public int getMaxRenderHeightMeta() {

        return quantaPerBlock - 1;
    }

    @Override
    public void updateTick(World world, int x, int y, int z, Random rand) {

        boolean changed = false;
        int quantaRemaining = world.getBlockMetadata(x, y, z) + 1;

        // Flow vertically if possible
        int prevRemaining = quantaRemaining;
        quantaRemaining = tryToFlowVerticallyInto(world, x, y, z, quantaRemaining);

        if (quantaRemaining < 1) {
            return;
        } else if (quantaRemaining != prevRemaining) {
            changed = true;

            if (quantaRemaining == 1) {
                world.setBlockMetadataWithNotify(x, y, z, quantaRemaining - 1, 2);
                return;
            }
        } else if (quantaRemaining == 1) {
            return;
        }

        // Flow out if possible
        int lowerthan = quantaRemaining - 1;

        if (displaceIfPossible(world, x, y, z - 1)) {
            world.setBlock(x, y, z - 1, 0);
        }
        if (displaceIfPossible(world, x, y, z + 1)) {
            world.setBlock(x, y, z + 1, 0);
        }
        if (displaceIfPossible(world, x - 1, y, z)) {
            world.setBlock(x - 1, y, z, 0);
        }
        if (displaceIfPossible(world, x + 1, y, z)) {
            world.setBlock(x + 1, y, z, 0);
        }
        int north = getQuantaValueBelow(world, x, y, z - 1, lowerthan);
        int south = getQuantaValueBelow(world, x, y, z + 1, lowerthan);
        int west = getQuantaValueBelow(world, x - 1, y, z, lowerthan);
        int east = getQuantaValueBelow(world, x + 1, y, z, lowerthan);
        int total = quantaRemaining;
        int count = 1;

        if (north >= 0) {
            ++count;
            total += north;
        }
        if (south >= 0) {
            ++count;
            total += south;
        }
        if (west >= 0) {
            ++count;
            total += west;
        }
        if (east >= 0) {
            ++count;
            total += east;
        }
        if (count == 1) {
            if (changed) {
                world.setBlockMetadataWithNotify(x, y, z, quantaRemaining - 1, 2);
            }
            return;
        }
        int each = total / count;
        int rem = total % count;
        if (north >= 0) {
            int newnorth = each;

            if (rem == count || rem > 1 && rand.nextInt(count - rem) != 0) {
                ++newnorth;
                --rem;
            }
            if (newnorth != north) {
                if (newnorth == 0) {
                    world.setBlock(x, y, z - 1, 0);
                } else {
                    world.setBlock(x, y, z - 1, blockID, newnorth - 1, 2);
                }
                world.scheduleBlockUpdate(x, y, z - 1, blockID, tickRate);
            }
            --count;
        }
        if (south >= 0) {
            int newsouth = each;

            if (rem == count || rem > 1 && rand.nextInt(count - rem) != 0) {
                ++newsouth;
                --rem;
            }
            if (newsouth != south) {
                if (newsouth == 0) {
                    world.setBlock(x, y, z + 1, 0);
                } else {
                    world.setBlock(x, y, z + 1, blockID, newsouth - 1, 2);
                }
                world.scheduleBlockUpdate(x, y, z + 1, blockID, tickRate);
            }
            --count;
        }
        if (west >= 0) {
            int newwest = each;

            if (rem == count || rem > 1 && rand.nextInt(count - rem) != 0) {
                ++newwest;
                --rem;
            }
            if (newwest != west) {
                if (newwest == 0) {
                    world.setBlock(x - 1, y, z, 0);
                } else {
                    world.setBlock(x - 1, y, z, blockID, newwest - 1, 2);
                }
                world.scheduleBlockUpdate(x - 1, y, z, blockID, tickRate);
            }
            --count;
        }
        if (east >= 0) {
            int neweast = each;

            if (rem == count || rem > 1 && rand.nextInt(count - rem) != 0) {
                ++neweast;
                --rem;
            }
            if (neweast != east) {
                if (neweast == 0) {
                    world.setBlock(x + 1, y, z, 0);
                } else {
                    world.setBlock(x + 1, y, z, blockID, neweast - 1, 2);
                }
                world.scheduleBlockUpdate(x + 1, y, z, blockID, tickRate);
            }
            --count;
        }
        if (rem > 0) {
            ++each;
        }
        world.setBlockMetadataWithNotify(x, y, z, each - 1, 2);
    }

    public int tryToFlowVerticallyInto(World world, int x, int y, int z, int amtToInput) {

        int otherY = y + densityDir;

        if (otherY < 0 || otherY >= world.getHeight()) {
            world.setBlockToAir(x, y, z);
            return 0;
        }
        int amt = getQuantaValueBelow(world, x, otherY, z, quantaPerBlock);

        if (amt >= 0) {
            amt += amtToInput;
            if (amt > quantaPerBlock) {
                world.setBlock(x, otherY, z, blockID, quantaPerBlock - 1, 3);
                world.scheduleBlockUpdate(x, otherY, z, blockID, tickRate);
                return amt - quantaPerBlock;
            } else if (amt > 0) {
                world.setBlock(x, otherY, z, blockID, amt - 1, 3);
                world.scheduleBlockUpdate(x, otherY, z, blockID, tickRate);
                world.setBlockToAir(x, y, z);
                return 0;
            }
            return amtToInput;
        } else {
            int density_other = getDensity(world, x, otherY, z);

            if (density_other == Integer.MAX_VALUE) {
                if (displaceIfPossible(world, x, otherY, z)) {
                    world.setBlock(x, otherY, z, blockID, amtToInput - 1, 3);
                    world.scheduleBlockUpdate(x, otherY, z, blockID, tickRate);
                    world.setBlockToAir(x, y, z);
                    return 0;
                } else {
                    return amtToInput;
                }
            }
            if (densityDir < 0) {
                if (density_other < density) // then swap
                {
                    int bId = world.getBlockId(x, otherY, z);
                    BlockFluidBase block = (BlockFluidBase) Block.blocksList[bId];
                    int otherData = world.getBlockMetadata(x, otherY, z);
                    world.setBlock(x, otherY, z, blockID, amtToInput - 1, 3);
                    world.setBlock(x, y, z, bId, otherData, 3);
                    world.scheduleBlockUpdate(x, otherY, z, blockID, tickRate);
                    world.scheduleBlockUpdate(x, y, z, bId, block.tickRate(world));
                    return 0;
                }
            } else {
                if (density_other > density) {
                    int bId = world.getBlockId(x, otherY, z);
                    BlockFluidBase block = (BlockFluidBase) Block.blocksList[bId];
                    int otherData = world.getBlockMetadata(x, otherY, z);
                    world.setBlock(x, otherY, z, blockID, amtToInput - 1, 3);
                    world.setBlock(x, y, z, bId, otherData, 3);
                    world.scheduleBlockUpdate(x, otherY, z, blockID, tickRate);
                    world.scheduleBlockUpdate(x, y, z, bId, block.tickRate(world));
                    return 0;
                }
            }
            return amtToInput;
        }
    }

    /* IFluidBlock */
    @Override
    public FluidStack drain(World world, int x, int y, int z, boolean doDrain) {

        return null;
    }

    @Override
    public boolean canDrain(World world, int x, int y, int z) {

        return false;
    }

}