package WayofTime.bloodmagic.compress;

import WayofTime.bloodmagic.BloodMagic;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.inventory.Container;
import net.minecraft.inventory.InventoryCrafting;
import net.minecraft.item.ItemStack;
import net.minecraft.item.crafting.CraftingManager;
import net.minecraft.item.crafting.IRecipe;
import net.minecraft.item.crafting.ShapedRecipes;
import net.minecraft.item.crafting.ShapelessRecipes;
import net.minecraft.world.World;
import net.minecraftforge.oredict.OreDictionary;
import net.minecraftforge.oredict.ShapedOreRecipe;
import net.minecraftforge.oredict.ShapelessOreRecipe;

import java.util.*;

public class StorageBlockCraftingRecipeAssimilator
{
    public List<IRecipe> getPackingRecipes()
    {
        // grab all recipes potentially suitable for packing or unpacking

        List<PackingRecipe> packingRecipes = new LinkedList<PackingRecipe>();
        List<IRecipe> unpackingRecipes = new ArrayList<IRecipe>();

        for (IRecipe recipe : getCraftingRecipes())
        {
            ItemStack output = recipe.getRecipeOutput();
            if (output == null || output.getItem() == null)
                continue;

            if (output.stackSize == 1)
            {
                PackingRecipe packingRecipe = getPackingRecipe(recipe);

                if (packingRecipe != null)
                {
                    packingRecipes.add(packingRecipe);
                }
            } else if ((output.stackSize == 4 || output.stackSize == 9) && recipe.getRecipeSize() == 1)
            {
                unpackingRecipes.add(recipe);
            }
        }

        // grab all packing recipes which accept the output of any of the
        // unpacking recipes

        Container container = makeDummyContainer();
        InventoryCrafting inventoryUnpack = new InventoryCrafting(container, 2, 2);
        InventoryCrafting inventory2x2 = new InventoryCrafting(container, 2, 2);
        InventoryCrafting inventory3x3 = new InventoryCrafting(container, 3, 3);
        World world = null; // TODO: use a proper dummy world?

        List<IRecipe> ret = new ArrayList<IRecipe>();

        for (IRecipe recipeUnpack : unpackingRecipes)
        {
            ItemStack unpacked = recipeUnpack.getRecipeOutput();
            InventoryCrafting inventory = null;

            for (Iterator<PackingRecipe> it = packingRecipes.iterator(); it.hasNext();)
            {
                PackingRecipe recipePack = it.next();

                // check if the packing recipe accepts the unpacking recipe's output

                boolean matched = false;

                if (recipePack.possibleInputs != null)
                {
                    // the recipe could be parsed, use its inputs directly since that's faster verify recipe size

                    if (recipePack.inputCount != unpacked.stackSize)
                        continue;

                    // check if any of the input options matches the unpacked
                    // item stack

                    for (ItemStack stack : recipePack.possibleInputs)
                    {
                        if (areInputsIdentical(unpacked, stack))
                        {
                            matched = true;
                            break;
                        }
                    }
                } else
                {
                    // unknown IRecipe, check through the recipe conventionally verify recipe size for 3x3 to skip anything smaller quickly

                    if (unpacked.stackSize == 9 && recipePack.recipe.getRecipeSize() < 9)
                        continue;

                    // initialize inventory late, but only once per unpack recipe

                    if (inventory == null)
                    {
                        if (unpacked.stackSize == 4)
                        {
                            inventory = inventory2x2;
                        } else
                        {
                            inventory = inventory3x3;
                        }

                        for (int i = 0; i < unpacked.stackSize; i++)
                        {
                            inventory.setInventorySlotContents(i, unpacked.copy());
                        }
                    }

                    // check if the packing recipe accepts the unpacked item
                    // stack

                    matched = recipePack.recipe.matches(inventory, world);
                }

                if (matched)
                {
                    // check if the unpacking recipe accepts the packing
                    // recipe's output

                    ItemStack packOutput = recipePack.recipe.getRecipeOutput();
                    inventoryUnpack.setInventorySlotContents(0, packOutput.copy());

                    if (recipeUnpack.matches(inventoryUnpack, world))
                    {
                        ret.add(recipePack.recipe);
                        it.remove();
                    }
                }
            }
        }

        return ret;
    }

    @SuppressWarnings("unchecked")
    private List<IRecipe> getCraftingRecipes()
    {
        return CraftingManager.getInstance().getRecipeList();
    }

    private Container makeDummyContainer()
    {
        return new Container()
        {
            @Override
            public boolean canInteractWith(EntityPlayer player)
            {
                return true;
            }
        };
    }

    private PackingRecipe getPackingRecipe(IRecipe recipe)
    {
        if (recipe.getRecipeSize() < 4)
            return null;

        List<?> inputs;

        if (recipe instanceof ShapedRecipes)
        {
            inputs = Arrays.asList(((ShapedRecipes) recipe).recipeItems);
        } else if (recipe instanceof ShapelessRecipes)
        {
            inputs = ((ShapelessRecipes) recipe).recipeItems;
        } else if (recipe instanceof ShapedOreRecipe)
        {
            inputs = Arrays.asList(((ShapedOreRecipe) recipe).getInput());
        } else if (recipe instanceof ShapelessOreRecipe)
        {
            inputs = ((ShapelessOreRecipe) recipe).getInput();
        } else
        {
            return new PackingRecipe(recipe, null, -1);
        }

        // check if the recipe inputs are size 4 or 9

        int count = 0;

        for (Object o : inputs)
        {
            if (o != null)
                count++;
        }

        if (count != 4 && count != 9)
            return null;

        // grab identical inputs

        List<ItemStack> identicalInputs = getIdenticalInputs(inputs);
        if (identicalInputs == null)
            return null;

        return new PackingRecipe(recipe, identicalInputs, count);
    }

    /**
     * Determine the item stacks from the provided inputs which are suitable for
     * every input element.
     * 
     * @param inputs
     *        List of all inputs, null elements are being ignored.
     * @return List List of all options.
     */
    @SuppressWarnings("unchecked")
    private List<ItemStack> getIdenticalInputs(List<?> inputs)
    {
        List<ItemStack> options = null;

        for (Object input : inputs)
        {
            if (input == null)
                continue;

            List<ItemStack> offers;

            if (input instanceof ItemStack)
            {
                offers = Collections.singletonList((ItemStack) input);
            } else if (input instanceof List)
            {
                offers = (List<ItemStack>) input;

                if (offers.isEmpty())
                    return null;
            } else
            {
                throw new RuntimeException("invalid input: " + input.getClass());
            }

            if (options == null)
            {
                options = new ArrayList<ItemStack>(offers);
                continue;
            }

            for (Iterator<ItemStack> it = options.iterator(); it.hasNext();)
            {
                ItemStack stackReq = it.next();
                boolean found = false;

                for (ItemStack stackCmp : offers)
                {
                    if (areInputsIdentical(stackReq, stackCmp))
                    {
                        found = true;
                        break;
                    }
                }

                if (!found)
                {
                    it.remove();

                    if (options.isEmpty())
                        return null;
                }
            }
        }

        return options;
    }

    private boolean areInputsIdentical(ItemStack a, ItemStack b)
    {

        try
        {
            if (a.getItem() != b.getItem())
                return false;

            int dmgA = a.getItemDamage();
            int dmgB = b.getItemDamage();

            return dmgA == dmgB || dmgA == OreDictionary.WILDCARD_VALUE || dmgB == OreDictionary.WILDCARD_VALUE;
        } catch (NullPointerException e)
        {

            BloodMagic.instance.getLogger().error("A mod in this instance has registered an item with a null input. Known problem mods are:");

            // String err = "";
            // for (String problem : problemMods)
            // err += (err.length() > 0 ? ", " : "") + problem;
            // BloodMagic.instance.getLogger().error(err);

            return false;
        }
    }

    private static class PackingRecipe
    {
        PackingRecipe(IRecipe recipe, List<ItemStack> possibleInputs, int inputCount)
        {
            this.recipe = recipe;
            this.possibleInputs = possibleInputs;
            this.inputCount = inputCount;
        }

        final IRecipe recipe;
        final List<ItemStack> possibleInputs;
        final int inputCount;
    }
}