package holeg.ui.controller;

import static holeg.serialize.ModelDeserializer.gson;

import holeg.model.AbstractCanvasObject;
import holeg.model.Edge;
import holeg.model.GroupNode;
import holeg.model.HolonElement;
import holeg.model.HolonObject;
import holeg.model.HolonSwitch;
import holeg.model.Model;
import holeg.preferences.ImagePreference;
import holeg.preferences.PreferenceKeys;
import holeg.serialize.CategoryAdapter;
import holeg.ui.model.GuiSettings;
import holeg.ui.model.IdCounter;
import holeg.ui.model.UndoHistory;
import holeg.ui.view.category.Category;
import holeg.utility.events.Action;
import holeg.utility.events.Event;
import holeg.utility.math.vector.Vec2i;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Optional;
import java.util.Set;
import java.util.logging.Logger;
import java.util.prefs.Preferences;


/**
 * The Class represents the controller.
 */
public class Control {

  private static final Logger log = Logger.getLogger(Control.class.getName());
  private static final Preferences prefs = Preferences.userNodeForPackage(Control.class);
  private final CanvasController canvasController;
  private final SimulationManager simulationManager;
  public Event OnCategoryChanged = new Event();
  public Event OnSelectionChanged = new Event();
  public Event OnCanvasUpdate = new Event();
  public Action<Boolean> OnGuiSetEnabled = new Action<>();
  public Action<GroupNode> OnShowGroupNode = new Action<>();
  public Action<GroupNode> OnRemoveGroupNode = new Action<>();
  public Event OnModelChanged = new Event();
  private Model model;

  public Control(Model model) {
    this.model = model;
    this.canvasController = new CanvasController(this);
    this.simulationManager = new SimulationManager(this);
    OnCanvasUpdate.addListener(() -> UndoHistory.addSave(saveModelToJsonString()));
    UndoHistory.addSave(saveModelToJsonString());
  }






  /* Operations for Categories and Objects */

  /**
   * init default category and objects.
   */
  public void resetCategories() {
    GuiSettings.getCategories().clear();
    initCategories();
    saveCategories();
  }

  /**
   * Add new Holon Object to a Category.
   */
  public void addObject(Category cat, String obj, List<HolonElement> list, String img) {
    addNewHolonObject(cat, obj, list, img);
    OnCategoryChanged.broadcast();
    saveCategories();
  }


  public void deleteCategory(Category category) {
    GuiSettings.getCategories().remove(category);
    OnCategoryChanged.broadcast();
    saveCategories();
  }

  /**
   * removes a selectedObject from selection.
   */
  public void removeObjectsFromSelection(Collection<AbstractCanvasObject> objects) {
    if (GuiSettings.getSelectedObjects().removeAll(objects)) {
      OnSelectionChanged.broadcast();
    }
  }

  /**
   * removes a selectedObject from selection.
   *
   * @param obj
   */
  public void removeObjectFromSelection(AbstractCanvasObject obj) {
    if (GuiSettings.getSelectedObjects().remove(obj)) {
      OnSelectionChanged.broadcast();
    }
  }

  public void addObjectToSelection(AbstractCanvasObject obj) {
    if (GuiSettings.getSelectedObjects().add(obj)) {
      OnSelectionChanged.broadcast();
    }
  }

  public void addObjectsToSelection(Collection<AbstractCanvasObject> objects) {
    if (GuiSettings.getSelectedObjects().addAll(objects)) {
      OnSelectionChanged.broadcast();
    }

  }


  public void setSelection(Collection<AbstractCanvasObject> objects) {
    GuiSettings.getSelectedObjects().clear();
    addObjectsToSelection(objects);
  }

  public void clearSelection() {
    if (!GuiSettings.getSelectedObjects().isEmpty()) {
      GuiSettings.getSelectedObjects().clear();
      OnSelectionChanged.broadcast();
    }
  }

  public void addObjectOnCanvas(GroupNode node, AbstractCanvasObject object) {
    canvasController.addObject(node, object);
    updateStateForIteration(model.getCurrentIteration());
  }


  /**
   * Deletes an CpsObject on the Canvas and its connections.
   *
   * @param obj AbstractCpsObject
   */
  public void deleteObject(AbstractCanvasObject obj) {
    canvasController.deleteObject(obj);
    if (obj instanceof GroupNode groupnode) {
      canvasController.deleteAllObjectsInGroupNode(groupnode);
    }
    calculateStateForCurrentIteration();
    OnCanvasUpdate.broadcast();
  }

  public void deleteCanvasObjects(Collection<AbstractCanvasObject> objects) {
    canvasController.deleteObjects(objects);
    calculateStateForCurrentIteration();
    OnCanvasUpdate.broadcast();
  }

  /**
   * Replaces {@code toBeReplaced} by {@code by} on the canvas
   *
   * @param toBeReplaced the object that will be replaced
   * @param by           the object that will replace it
   */
  public void replaceCanvasObject(AbstractCanvasObject toBeReplaced, AbstractCanvasObject by) {
    canvasController.replaceObject(toBeReplaced, by);
    OnCanvasUpdate.broadcast();
  }

  /**
   * Add an edge to the Canvas.
   *
   * @param edge the edge
   */
  public boolean addEdgeOnCanvas(Edge edge) {
    if (doesEdgeExist(edge)) {
      return false;
    }
    canvasController.addEdgeOnCanvas(edge);
    OnCanvasUpdate.broadcast();
    return true;
  }

  public boolean doesEdgeExist(Edge edge) {
    boolean connectsToSelf = edge.getA() == edge.getB();
    return !connectsToSelf && model.getEdgesOnCanvas().stream()
        .anyMatch(e -> (e.getA() == edge.getA() && e.getB() == edge.getB())
            || (e.getB() == edge.getA() && e.getA() == edge.getB()));
  }


  /**
   * Add an edge to the Canvas.
   *
   * @param edge the edge
   */
  public void addEdgeOnCanvasOrRemoveExisting(Edge edge) {
    boolean connectsToSelf = edge.getA() == edge.getB();
    if (connectsToSelf) {
      return;
    }
    Optional<Edge> edgeToRemove = model.getEdgesOnCanvas().stream()
        .filter(e -> (e.getA() == edge.getA() && e.getB() == edge.getB())
            || (e.getB() == edge.getA() && e.getA() == edge.getB())).findAny();
    edgeToRemove.ifPresentOrElse(canvasController::removeEdgesOnCanvas,
        () -> canvasController.addEdgeOnCanvas(edge));
    updateStateForCurrentIteration();
  }


  public void calculateStateForCurrentIteration() {
    simulationManager.calculateStateForIteration(model.getCurrentIteration());
  }

  public void updateStateForCurrentIteration() {
    simulationManager.calculateStateForIteration(model.getCurrentIteration());
    OnCanvasUpdate.broadcast();
  }

  /**
   * calculates the flow of the edges and the supply for objects.
   *
   * @param x current Iteration
   */
  public void updateStateForIteration(int x) {
    simulationManager.calculateStateForIteration(x);
    OnCanvasUpdate.broadcast();
  }

  /**
   * resets the whole State of the simulation including a reset of all Edges to the default "is
   * working" state
   */
  public void resetSimulation() {
    model.reset();
  }


  /**
   * Getter for Model.
   *
   * @return the Model
   */
  public Model getModel() {
    return model;
  }


  /**
   * Copy all Selected Objects.
   */
  public void copy() {
    GuiSettings.getClipboardObjects().clear();
    GuiSettings.getClipboardObjects().addAll(GuiSettings.getSelectedObjects());
    GuiSettings.getClipboardEdges().clear();
    GuiSettings.getClipboardEdges()
        .addAll(getEdgesBetweenObjects(GuiSettings.getSelectedObjects()));
  }

  private List<Edge> getEdgesBetweenObjects(Collection<AbstractCanvasObject> selectedObjects) {
    return model.getEdgesOnCanvas().stream()
        .filter(edge -> selectedObjects.containsAll(Arrays.asList(edge.getA(), edge.getB())))
        .toList();
  }

  public void paste(GroupNode groupNode, Vec2i offset) {
    if (GuiSettings.getClipboardObjects().isEmpty()) {
      return;
    }
    HashMap<AbstractCanvasObject, AbstractCanvasObject> oldToNew = new HashMap<>();
    Collection<AbstractCanvasObject> copies = GuiSettings.getClipboardObjects().stream()
        .map(obj -> {
          AbstractCanvasObject copy = obj.copy();
          oldToNew.put(obj, copy);
          return copy;
        }).toList();
    copies.forEach(obj -> {
      obj.getPosition().addAssign(offset);
      obj.getPosition().clampX(0, GuiSettings.canvasSize.getX());
      obj.getPosition().clampY(0, GuiSettings.canvasSize.getY());
    });
    groupNode.addAll(copies);
    Collection<Edge> copyEdges = GuiSettings.getClipboardEdges().stream().map(
            edge -> new Edge(oldToNew.get(edge.getA()), oldToNew.get(edge.getB()), edge.maxCapacity))
        .toList();
    model.getEdgesOnCanvas().addAll(copyEdges);
    updateStateForCurrentIteration();
    OnSelectionChanged.broadcast();
  }

  public void cut() {
    copy();
    deleteCanvasObjects(GuiSettings.getSelectedObjects());
    clearSelection();
  }


  public void guiSetEnabled(boolean state) {
    OnGuiSetEnabled.broadcast(state);
  }


  /**
   * init default category and objects.
   */
  private void initCategories() {
    Category energy = createCategoryWithName("Energy");
    Category building = createCategoryWithName("Building");
    Category component = createCategoryWithName("Component");
    HolonObject powerPlant = addNewHolonObject(energy, "Power Plant", new ArrayList<>(),
        ImagePreference.Canvas.DefaultObject.PowerPlant);
    HolonObject house = addNewHolonObject(building, "House", new ArrayList<>(),
        ImagePreference.Canvas.DefaultObject.House);
    HolonSwitch sw = new HolonSwitch("Switch");
    component.getObjects().add(sw);
    powerPlant.add(new HolonElement(null, "Power", 10000));
    energy.getObjects().add(powerPlant);

    house.add(new HolonElement(null, "TV", -250));
    house.add(new HolonElement(null, "TV", -250));
    house.add(new HolonElement(null, "Fridge", -500));
    house.add(new HolonElement(null, "Radio", -100));
    house.add(new HolonElement(null, "PC", -250));
    house.add(new HolonElement(null, "PC", -250));
    house.add(new HolonElement(null, "PC", -250));
    house.add(new HolonElement(null, "Light", -50));
    house.add(new HolonElement(null, "Light", -50));
    house.add(new HolonElement(null, "Light", -50));
    house.add(new HolonElement(null, "Light", -50));
    house.add(new HolonElement(null, "Light", -50));
    house.add(new HolonElement(null, "Solar Panel", 300));
    building.getObjects().add(house);
    OnCategoryChanged.broadcast();
  }


  public Category createCategoryWithName(String categoryName) {
    Optional<Category> category = findCategoryWithName(categoryName);
    if (category.isEmpty()) {
      Category cat = new Category(categoryName);
      GuiSettings.getCategories().add(cat);
      OnCategoryChanged.broadcast();
      return cat;
    } else {
      return category.get();
    }

  }


  /**
   * Add Object into a Category.
   *
   * @param category Category
   * @param object   Object
   */
  public void addObject(Category category, AbstractCanvasObject object) {
    int i = 0;
    while (category.findObjectWithName(object.getName()).isPresent()) {
      if (object.getName().contains("_")) {
        object.setName(object.getName().substring(0, object.getName().indexOf('_')));
      }
      object.setName(object.getName() + "_" + i);
      i++;
    }
    category.getObjects().add(object);
  }

  /**
   * Add new Holon Object to a Category.
   *
   * @param category Category
   * @param object   New Object Name
   * @param list     Array of Elements
   * @param image    the image Path
   */
  public HolonObject addNewHolonObject(Category category, String object, List<HolonElement> list,
      String image) {
    HolonObject obj = new HolonObject(object);
    obj.setImagePath(image);
    obj.clearElements();
    obj.add(list);
    addObject(category, obj);
    return obj;
  }


  public Optional<Category> findCategoryWithName(String categoryName) {
    return GuiSettings.getCategories().stream().filter(cat -> cat.getName().equals(categoryName))
        .findAny();
  }

  public void loadFile(File file) {
    log.info("load" + file);
    try {
      FileReader reader = new FileReader(file);
      Model model = gson.fromJson(reader, Model.class);
      reader.close();
      this.model = model;
      calculateStateForCurrentIteration();
      OnModelChanged.broadcast();
    } catch (IOException e) {
      log.warning(e.getLocalizedMessage());
    }
    clearSelection();
    GuiSettings.setActualSaveFile(file);
  }

  public void loadModelFromJsonString(String json) {
    this.model = gson.fromJson(json, Model.class);
    calculateStateForCurrentIteration();
    OnModelChanged.broadcast();
  }

  public String saveModelToJsonString() {
    return gson.toJson(model);
  }


  public void toggleSelectedObjects(Collection<AbstractCanvasObject> objects) {
    Set<AbstractCanvasObject> intersection = new HashSet<>(objects);
    intersection.retainAll(GuiSettings.getSelectedObjects());
    GuiSettings.getSelectedObjects().addAll(objects);
    GuiSettings.getSelectedObjects().removeAll(intersection);
    OnSelectionChanged.broadcast();
  }


  public void saveFile(File file) {
    log.info("save" + file);
    try {
      FileWriter writer = new FileWriter(file);
      gson.toJson(model, writer);
      writer.close();
    } catch (IOException e) {
      log.warning(e.getLocalizedMessage());
    }
    GuiSettings.setActualSaveFile(file);
  }

  public void group() {
    canvasController.group(GuiSettings.getSelectedObjects());
    clearSelection();
    OnCanvasUpdate.broadcast();
  }

  public void ungroup() {
    canvasController.ungroup(GuiSettings.getSelectedObjects());
    clearSelection();
    OnCanvasUpdate.broadcast();
  }


  public void undo() {
    UndoHistory.undo().ifPresent(this::loadModelFromJsonString);
  }

  public void redo() {
    UndoHistory.redo().ifPresent(this::loadModelFromJsonString);
  }


  public void clearModel() {
    model.clear();
    clearSelection();
    model.setCurrentIteration(0);
    IdCounter.reset();
    calculateStateForCurrentIteration();
    OnModelChanged.broadcast();
    GuiSettings.setActualSaveFile(null);
  }

  public void showGroupNode(GroupNode groupNode) {
    OnShowGroupNode.broadcast(groupNode);
    clearSelection();
  }


  public void loadCategory() {
    String json = prefs.get(PreferenceKeys.Category.DefaultCategory, "Init");
    if (json.equals("Init")) {
      initCategories();
      return;
    }
    GuiSettings.getCategories().clear();
    GuiSettings.getCategories()
        .addAll(CategoryAdapter.Gson.fromJson(json, CategoryAdapter.CategorySet));
    OnCategoryChanged.broadcast();

  }

  public void saveCategories() {
    String json = CategoryAdapter.Gson.toJson(GuiSettings.getCategories());
    prefs.put(PreferenceKeys.Category.DefaultCategory, json);
  }
}