package com.mousetech.gourmetj;

import java.io.ByteArrayOutputStream;
import java.io.PrintWriter;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;
import java.util.stream.Collectors;

import javax.annotation.PostConstruct;
import javax.faces.view.ViewScoped;
import javax.inject.Inject;
import javax.inject.Named;

import org.apache.commons.lang3.StringUtils;
import org.primefaces.model.ByteArrayContent;
import org.primefaces.model.DefaultStreamedContent;
import org.primefaces.model.StreamedContent;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.mousetech.gourmetj.persistence.dao.ShopcatRepository;
import com.mousetech.gourmetj.persistence.model.Ingredient;
import com.mousetech.gourmetj.persistence.model.Recipe;
import com.mousetech.gourmetj.persistence.model.Shopcat;
import com.mousetech.gourmetj.utils.YamlShoppingList;

@Named
@ViewScoped
public class ShoppingListBean implements Serializable {

	public class RecipeReference {

		private int count;
		private Recipe recipe;

		/**
		 * Constructor Constructor.
		 * 
		 * @param r Recipe to reference (from Shopping List)
		 */
		public RecipeReference(Recipe r) {
			count = 1;
			recipe = r;
		}

		/**
		 * @return the count
		 */
		public int getCount() {
			return count;
		}

		/**
		 * @param count the count to set
		 */
		public void setCount(int count) {
			this.count = count;
		}

		/**
		 * @return the recipe
		 */
		public Recipe getRecipe() {
			return recipe;
		}

		/**
		 * @param recipe the recipe to set
		 */
		public void setRecipe(Recipe recipe) {
			this.recipe = recipe;
		}

	}

	/**
	 * Serial version for session save/restore
	 */
	private static final long serialVersionUID =
			7449440266704831598L;

	/* Logger */

	@SuppressWarnings("unused")
	private static final Logger log =
			LoggerFactory.getLogger(ShoppingListBean.class);

	@Inject
	private UserSession userSession;

	private List<ShopIngredient> siList;

	private List<RecipeReference> recipeList;

	@PostConstruct
	public void init() {
		// Load up details on recipes
		this.siList = new ArrayList<ShopIngredient>(30);
		buildMaps();
	}

	public List<RecipeReference> getRecipeList() {
		if (this.recipeList == null) {
			this.recipeList = loadRecipeList();
		}
		return this.recipeList;
	}

	private List<RecipeReference> loadRecipeList() {
		List<RecipeReference> list =
				userSession.getShoppingList().stream()
					.map(r -> new RecipeReference(r))
					.collect(Collectors.toList());
		return list;
	}

	public List<ShopIngredient> getIngredientList() {
		return this.siList;
	}

	private void buildMaps() {
		this.siList = new ArrayList<ShopIngredient>(30);
		for (RecipeReference r : this.getRecipeList()) {
			buildMapsFor(r);
		}
		// Now consolidate amounts and sort by
		// shopcat/item/ingkey
		optimizeIngredients(this.siList);

		this.siList.sort(new ShopclassComparator());
	}

	/**
	 * Run the ingredient list for the selected recipe and add
	 * them to siList
	 * 
	 * @param r
	 * 
	 * @see #buildMaps()
	 */
	private void buildMapsFor(RecipeReference r) {
		final int multiplier = r.getCount();
		if (multiplier == 0) {
			return;
		}
		for (Ingredient ing : r.getRecipe()
			.getIngredientHash()) {
			String ingkey = ing.getIngkey();
			if (StringUtils.isBlank(ingkey)) {
				continue;
			}
			String shopCatName = ing.getShopCat() != null
					? ing.getShopCat().getShopcategory()
					: null;
			ShopIngredient sing;
			try {
				Double amt = ing.getAmount();
				if (multiplier > 1 && (amt != null)) {
					amt *= multiplier;
				}
				sing = new ShopIngredient(amt, ing.getUnit(),
						ing.getItem(), ing.getIngkey(),
						shopCatName);
				siList.add(sing);
			} catch (Exception e) {
				log.error("Unable to create ShopIngredient for "
						+ r.getRecipe() + " Ingredient " + ing);
				e.printStackTrace();
			}
		}
	}

	/**
	 * Sort ShopIngredient list, then optimize it by
	 * consolidating amounts where possible.
	 * 
	 * @param victim List to optimize
	 * 
	 *               #TestedBy @see ShoppingListBeanTest
	 */
	static void optimizeIngredients(
			List<ShopIngredient> victim) {
		victim.sort(null);
		for (int i = 0; i < (victim.size() - 1); i++) {
			ShopIngredient si = victim.get(i);
			ShopIngredient si2 = victim.get(i + 1);
			if (si.compareTo(si2) == 0) {
				si.setAmount(si.getAmount() + si2.getAmount());
				victim.remove(si2); // reduces size()
			}
		}
	}

	class ShopclassComparator
			implements Comparator<ShopIngredient> {

		@Override
		public int compare(ShopIngredient ing1,
				ShopIngredient ing2) {
			int i = 0;
			i = relate(ing1.getShopCat(), ing2.getShopCat());
			if (i != 0) {
				return i;
			}
			i = relate(ing1.getItem(), ing2.getItem());
			if (i != 0) {
				return i;
			}
			i = relate(ing1.getIngkey(), ing2.getIngkey());
			if (i != 0) {
				return i;
			}
			return 0;
		}

		private int relate(String item2, String item3) {
			if ((item2 == null) && (item3 == null)) {
				return 0;
			}
			if (item2 == null) {
				return -1;
			}
			if (item3 == null) {
				return 1;
			}
			return item2.compareTo(item3);
		}
	}

	public StreamedContent getDlIngredientList() {
		return YamlShoppingList
			.createDownload(getIngredientList());
	}

	// =============================================
	private List<String> shopcatList;

	public List<String> getShopcatList() {
		if (shopcatList == null) {
			shopcatList = loadShopcatList();
		}
		return shopcatList;
	}

	@Inject
	ShopcatRepository shopcatRepository;

	private List<String> loadShopcatList() {
		return shopcatRepository.findDistinctCategoryNative();
//			.findAllByOrderByShopcategoryAsc();
	}

	private Shopcat xeditShopcat = new Shopcat();

	private String oldShopcategoryName;

	/**
	 * @return the editShopcat
	 */
	public Shopcat getEditShopcat() {
		return xeditShopcat;
	}

	public void doEditShopcat(int scId) {
//		xeditShopcat = null;
//		final List<Shopcat> scl = getShopcatList();
//		for (Shopcat sc : scl) {
//			if (sc.getId() == scId) {
//				xeditShopcat = sc;
//				this.oldShopcategoryName = sc.getShopcategory();
//				if (sc.getPosition() == null) {
//					sc.setPosition(0);
//				}
//				return;
//			}
//		}
//		log.error("SHOPCAT " + scId + " NOT FOUND");
	}

	public void ajaxOnClickShopcatIngkey() {
		// Saves 1 shopcat/ingkey
		this.shopcatRepository.save(xeditShopcat);
		this.shopcatList = null;
	}

	/**
	 * Updates all ingredient keys for shopcat name-change. Note
	 * that once done, this cannot be undone!
	 */
	public void ajaxOnClickShopcat() {
		this.shopcatRepository.UpdateShopcats(
			this.oldShopcategoryName,
			xeditShopcat.getShopcategory());
		this.shopcatList = null;
	}

	/**
	 * Primefaces AJAX listener for changes to amount values of
	 * recipes the recipe list. Forces re-computation of
	 * ingredient requirements.
	 */
	public void pfAmountChange() {
		buildMaps();
	}

	// ===
	private String selectedShopcat;

	/**
	 * @return the selectedShopcat
	 */
	public String getSelectedShopcat() {
		return selectedShopcat;
	}

	/**
	 * @param selectedShopcat the selectedShopcat to set
	 */
	public void setSelectedShopcat(String selectedShopcat) {
		this.selectedShopcat = selectedShopcat;
		this.ingkeyList = null;
	}

	private List<String> selectedIngkey;

	/**
	 * @return the selectedIngkey
	 */
	public List<String> getSelectedIngkey() {
		return selectedIngkey;
	}

	/**
	 * @param selectedIngkey the selectedIngkey to set
	 */
	public void setSelectedIngkey(List<String> selectedIngkey) {
		this.selectedIngkey = selectedIngkey;
	}

	private List<String> ingkeyList;

	/**
	 * @return the ingkeyList
	 */
	public List<String> getIngkeyList() {
		if (ingkeyList == null) {
			ingkeyList = loadIngkeyListFor(selectedShopcat);
		}
		return ingkeyList;
	}

	private List<String> loadIngkeyListFor(
			String selectedShopcat2) {
		List<String> list = this.shopcatRepository
			.findByIngkeySorted(selectedShopcat2);
		return list;
	}

	private String newShopcat;

	/**
	 * @return the newShopcat
	 */
	public String getNewShopcat() {
		return newShopcat;
	}

	/**
	 * @param newShopcat the newShopcat to set
	 */
	public void setNewShopcat(String newShopcat) {
		this.newShopcat = newShopcat;
	}

	public List<String> suggestShopcat(String query) {
		return this.shopcatList;
	}

	public void doChangeShopcat() {
		String oldCat = this.getSelectedShopcat();
		String newCat = this.getNewShopcat();
		if (oldCat.equals(newCat)) {
			return; // effective NO-OP
		}
		newCat = newCat.trim();
		if (StringUtils.isBlank(newCat)) {
			this.shopcatRepository
				.deleteShopcatFor(this.getSelectedIngkey());
		} else {
			this.shopcatRepository.updateShopcatFor(newCat,
				this.getSelectedIngkey());
		}
	}

}