import {EventEmitter, Injectable} from '@angular/core';
import {ApiService, LshData, Parameters, RawData, State, StateNode, TableInfoData} from './api.service';

@Injectable({
  providedIn: 'root'
})
/**
 * This service acts as the state of the entire application. Components can subscribe to EventEmitters within this state to update their
 * contents.
 */
export class StateService {
  /**
   * These are all LSH specific variables. The variables can be accessed using the getters and setters
   */
  public currStateIndex = 0;
  public maxStateIndex = 0;
  public states: {[idx: number]: StateNode} = {};
  private _rawData: RawData[];
  private _lshData: LshData;
  private _queryWindow: number[][];
  private _weights: number[];
  private _labels = {};
  private _lshParameters: number[];
  private _selection: number[];
  public computedTime = 0;
  public windowSize = 120;
  public nrOfTables = 5;
  public hashSize = 5;
  public stepSize = 200;
  public loadingText = '';

  /**
   * These are all GUI variables
   */
  public loadingProgress = 0;
  public querySelectionMode = true;
  private _currentTab: number;
  private _sliderValue;

  /**
   * These are all EventEmitters. Subscribe to these if you want to be informed about an update in state.
   */
  public onNewData: EventEmitter<void> = new EventEmitter<void>();
  public onNewWindows: EventEmitter<void> = new EventEmitter<void>();
  public onNewQuery: EventEmitter<void> = new EventEmitter<void>();
  public onNewLshData: EventEmitter<void> = new EventEmitter<void>();

  public onNewLabels: EventEmitter<void> = new EventEmitter<void>();
  public onNewTab: EventEmitter<void> = new EventEmitter<void>();
  public onNewSlider: EventEmitter<number> = new EventEmitter<number>();
  public onNewSelection: EventEmitter<number[]> = new EventEmitter<number[]>();

  constructor(private api: ApiService) {
     this._selection = [0];
     this.initialize();
  }

  /**
   * This function initializes the application. It retrieves the raw data and creates windows.
   */
  async initialize(): Promise<void> {
    this.loadingProgress = 0;
    await this.getRawData();
    // this.loadingProgress = 50;
    // await this.createWindows();
    this.loadingProgress = 100;
  }

  /**
   * This function resets the application. It re-creates the windows
   */
  async reset(): Promise<void> {
    this.loadingProgress = 50;
    await this.createWindows();
    this.loadingProgress = 100;
  }

  /**
   * This function retrieves the raw data
   */
  async getRawData(): Promise<void> {
    this.rawData = await this.api.readFile();
    console.log('Printing raw data:');
    console.log(this.rawData);
  }

  /**
   * This function creates the windows on the server side
   */
  async createWindows(): Promise<void> {
    await this.api.createWindows(this.parameters);
    this.onNewWindows.emit();
  }



  /**
   * This function performs the first iteration of LSH
   */
  async lshInitial(): Promise<void> {
    this._weights = Array(this._queryWindow.length).fill(1);
    const t0 = new Date().getTime();
    this.loadingText = 'Calculating optimal LSH parameters';
    this._lshParameters = await this.api.getParameters();
    this.loadingText = 'Creating LSH model';
    const lshData = await this.api.lshUpdate(this._queryWindow, this._weights, this._lshParameters);
    this.computedTime = new Date().getTime() - t0;
    this.loadingText = '';
    this.lshData = lshData;
  }

  /**
   * This function performs every other iteration of LSH
   */
  async update(labels, hashFunctions): Promise<void> {
    this.loadingText = 'Calculating new model parameters';
    this._weights = await this.api.getWeights(this._queryWindow, labels, this._weights, hashFunctions);
    const t0 = new Date().getTime();
    this.loadingText = 'Creating LSH model';
    const lshData = await this.api.lshUpdate(this._queryWindow, this._weights, this._lshParameters);
    this.computedTime = new Date().getTime() - t0;
    this.loadingText = '';
    this.lshData = lshData;
  }

  /**
   * This function retrieves additional information given a table
   */
  async getTableInfo(table: number[][]): Promise<TableInfoData> {
    return await this.api.getTableInfo(table);
  }

  /**
   * This function retrieves the query
   */
  async getQueryWindow(windowIndex: number | {[index: number]: boolean}, querySize, startIndex): Promise<number[][]> {
    this.queryWindow = await this.api.getQueryWindow(windowIndex, querySize, startIndex);
    console.log('Printing query:');
    console.log(this.queryWindow);
    return this._queryWindow;
  }

  /**
   * This function retrieves the window given the window index
   */
  async getWindow(indices: number[]): Promise<number[][][]> {
    return await this.api.getWindowByIndices(indices);
  }

  public async saveState() {
    this.maxStateIndex++;
    if (this.currStateIndex > 0) {
      if (!this.states[this.currStateIndex].children) {
        this.states[this.currStateIndex].children = [];
      }
      this.states[this.currStateIndex].children.push(this.maxStateIndex);
    }
    this.states[this.maxStateIndex] = {
      id: this.maxStateIndex,
      state: this.state,
      image: undefined,
      children: undefined
    };
    console.log(this.states[this.maxStateIndex]);
    this.currStateIndex = this.maxStateIndex;
  }

  public loadState(stateIndex) {
    const stateNode = this.states[stateIndex];
    this.currStateIndex = Number(stateNode.id);
    this._lshData = stateNode.state.lshData;
    this.queryWindow = stateNode.state.queryWindow;
    this._weights = stateNode.state.weights;
    this.labels = stateNode.state.labels;
    this.onNewLshData.emit();
  }

  /**
   * These are all setters and getters
   */
  public set rawData(v: RawData[]) {
    this._rawData = v;
    this.onNewData.emit();
  }

  public get rawData(): RawData []{
    return this._rawData;
  }

  public set lshData(v: LshData) {
    this._lshData = v;
    this.saveState();
    console.log(this.states);
    this.onNewLshData.emit();
  }

  public get lshData(): LshData {
    return this._lshData;
  }

  public set labels(v) {
    this._labels = v;
    this.onNewLabels.emit();
  }

  public get labels() {
    return this._labels;
  }

  public set currentTab(v: number) {
    this._currentTab = v;
    this.onNewTab.emit();
  }

  public get currentTab(): number {
    return this._currentTab;
  }

  public set sliderValue(v: number) {
    this._sliderValue = v;
    this.onNewSlider.emit(v);
  }

  public get sliderValue(): number {
    return this._sliderValue;
  }

  public set selection(v: number[]) {
    this._selection = v;
    this.onNewSelection.emit(v);
  }

  public get selection(): number[] {
    return this._selection;
  }

  public set queryWindow(v: number[][]) {
    this._queryWindow = v;
    this.onNewQuery.emit();
  }

  public get queryWindow(): number[][] {
    return this._queryWindow;
  }

  public get lshParameters(): number[] {
    return this._lshParameters;
  }

  public get parameters(): Parameters {
    return {
      windowsize: this.windowSize,
      hashsize: this.hashSize,
      tablesize: this.nrOfTables,
      stepsize: this.stepSize
    };
  }

  public get colors(): string[] {
    return ['#377eb8', '#ff7f00', '#4daf4a',
      '#f781bf', '#a65628', '#984ea3',
      '#999999', '#e41a1c', '#dede00'];
  }

  public get state(): State {
    return {
      lshData: this.lshData,
      queryWindow: this.queryWindow,
      weights: this._weights,
      labels: this.labels
    };
  }
}