import {HttpClient} from '@angular/common/http';
import {Injectable} from '@angular/core';
import {Vector as VectorLayer} from 'ol/layer';

import {HsDialogContainerService} from 'hslayers-ng/components/layout/dialogs/dialog-container.service';
import {HsUtilsService} from 'hslayers-ng/components/utils/utils.service';

import attractivenessConfig from '../attractiveness.config.json';
import clusteringMethods from '../data/clustering_methods.json';
import {AdjusterEventService} from './adjuster-event.service';
import {AdjusterLegendService} from './adjuster-legend.service';
import {AdjusterLoaderComponent} from './adjuster-loader.component';
import {AttractivenessClustersService} from './attractiveness-clusters.service';
import {AttractivenessIndexService} from './attractiveness-index.service';
import {nuts} from '../nuts';

@Injectable({providedIn: 'root'})
export class AdjusterService {
  /** To be read from a config file */
  allowedClusteringMethods: Array<string>;
  /** To be read from a config file */
  initialWeights: Record<string, number>;
  /** To be read from a config file */
  serviceBaseUrl: string;
  /** Used in the UI as a selector */
  allowClusters = true;
  /** Used in the UI as a selector */
  allowIndex = true;
  factors = [];
  clusters = [];
  numberOfClusters: number;
  method: string;
  methods: Array<MethodDescription>;
  private _clusteringInProcess: boolean;
  private _clustersLoaded: boolean;
  private _loadInProcess: boolean;
  private _raiInProcess: boolean;

  constructor(
    public adjusterEventService: AdjusterEventService,
    public adjusterLegendService: AdjusterLegendService,
    public attractivenessIndexService: AttractivenessIndexService,
    public attractivenessClustersService: AttractivenessClustersService,
    public hsDialogContainerService: HsDialogContainerService,
    public hsUtilsService: HsUtilsService,
    public httpClient: HttpClient
  ) {
    // First safely set configurable properties
    this.allowedClusteringMethods =
      attractivenessConfig?.allowedClusteringMethods ?? [];
    this.initialWeights = attractivenessConfig?.initialWeights ?? {};
    this.serviceBaseUrl =
      attractivenessConfig?.serviceBaseUrl ??
      'https://publish.lesprojekt.cz/nodejs/';
    // 'https://jmacura.ml/ws/' // 'http://localhost:3000/'
    this.methods = clusteringMethods.filter((m) =>
      this.allowedClusteringMethods.includes(m.codename)
    );
    this.method = 'haclustwd2'; //TODO: set in config/or not use at all?
    this.numberOfClusters = 12;
  }

  /**
   * Sends a request to polirural-attractiveness-service
   * and applies the returned values
   */
  apply(): void {
    if (this.allowIndex) {
      this.calculateIndex();
    }
    if (this.allowClusters) {
      this.calculateClusters();
    }
  }

  async calculateIndex(): Promise<void> {
    this._raiInProcess = true;
    let attractivenessData: any;
    try {
      attractivenessData = await this.httpClient
        .post(this.serviceBaseUrl + 'eu/scores/', {
          factors: this.factors.map((f) => {
            return {
              factor: f.name,
              weight: f.weight,
              datasets: f.datasets
                .filter((ds) => ds.included)
                .map((ds) => ds.name),
            };
          }),
        })
        .toPromise();
    } catch (error) {
      console.warn(`Error obtaining data from ${this.serviceBaseUrl}.`);
      console.log(error);
      this._raiInProcess = false;
      this.adjusterEventService.loaded.next({
        success: true,
        type: 'index',
        err: error,
      });
    }
    // Spread the 'aggregate' value between 0 and 1
    const min = attractivenessData.reduce((a, b) =>
      a.aggregate < b.aggregate ? a : b
    ).aggregate;
    const max = attractivenessData.reduce((a, b) =>
      a.aggregate > b.aggregate ? a : b
    ).aggregate;
    const coefficient = 1 / (max - min);
    const constant = -min * coefficient;
    attractivenessData.forEach((a) => {
      a.aggregate *= coefficient;
      a.aggregate += constant;
    });
    // Store relation between region and its data in a hash-table-like structure
    // more memory consuming, but faster then find()
    const codeRecordRelations = {};
    attractivenessData.forEach((a) => {
      codeRecordRelations[a.code.toUpperCase()] = a;
    });
    console.time('forEach-Index');
    this.attractivenessIndexService.processIndex(codeRecordRelations);
    console.timeEnd('forEach-Index');
    this._raiInProcess = false;
    this.adjusterEventService.loaded.next({
      success: true,
      type: 'index',
    });
  }

  calculateClusters(): void {
    this._clusteringInProcess = true;
    this.httpClient
      .post(this.serviceBaseUrl + 'eu/clusters/', {
        numberOfClusters: this.numberOfClusters,
        factors: this.factors.map((f) => {
          return {
            factor: f.name,
            weight: f.weight,
            datasets: f.datasets
              .filter((ds) => ds.included)
              .map((ds) => ds.name),
          };
        }),
      })
      .toPromise()
      .then((data: any) => {
        const clusterData = data.response;
        // Store relation between region and its data in a hash-table-like structure
        // more memory consuming, but much faster then find()
        const codeRecordRelations = {};
        clusterData.forEach((c) => {
          codeRecordRelations[c['nuts_id'].toUpperCase()] = c;
        });
        console.time('forEach-Cluster');
        /*const clusters = [];
        for (const region of clusterData) {
          if (!clusters.includes(region[this.method])) {
            clusters.push(region[this.method]);
          }
        }*/
        //for (const method of this.methods) {
        this.attractivenessClustersService.processClusters(codeRecordRelations);
        //}
        console.timeEnd('forEach-Cluster');
        /*let max = 0;
        this.clusters.forEach((a) => {
          if (a.aggregate > max) {
            max = a.aggregate;
          }
        });
        const normalizer = 1 / max;
        this.attractivity.forEach((a) => {
          a.aggregate *= normalizer;
        });
        this.attractivity.forEach((a) => {
          this.nutsCodeRecordRelations[a.code] = a;
        });*/
        // Fake the legend
        nuts.nuts3ClustersSource.legend_categories = this.adjusterLegendService.createClusterLegend(
          this.numberOfClusters
        );
        this._clustersLoaded = true;
        this._clusteringInProcess = false;
        this.adjusterEventService.loaded.next({
          success: true,
          type: 'clusters',
        });
      })
      .catch((error) => {
        console.warn(`Error obtaining data from ${this.serviceBaseUrl}.`);
        console.log(error);
        this._clusteringInProcess = false;
        this.adjusterEventService.loaded.next({
          success: false,
          type: 'clusters',
          err: error,
        });
      });
  }

  init(): void {
    this._loadInProcess = true;
    this.httpClient
      .get(this.serviceBaseUrl + 'eu/datasets/')
      .toPromise()
      .then((data: any) => {
        this.factors = data.map((dataset) => {
          return {
            name: dataset.Factor,
            weight: this.initialWeights[dataset.Factor] ?? 1,
            datasets: [],
          };
        });
        this.factors = this.hsUtilsService.removeDuplicates(
          this.factors,
          'name'
        );
        this.factors.forEach((factor) => {
          factor.datasets = data
            .filter((ds) => ds.Factor === factor.name)
            .map((ds) => {
              return {
                name: ds.Name,
                desc: ds.Description,
                included: true,
              };
            });
        });
        this._loadInProcess = false;
        this.apply();
        // In HSL 2.5, setting layer greyscale breaks the print() functionality
        //this.hsLayerManagerService.setGreyscale(osmLayer);
      })
      .catch((error) => {
        console.warn(`Web service at ${this.serviceBaseUrl} unavailable!`);
        console.log(error);
        this._loadInProcess = false;
        /*this.adjusterEventService.loaded.next({
          success: false,
          err: error,
        });*/
      });
  }

  clustersLoaded(): boolean {
    return this._clustersLoaded;
  }

  /**
   * @returns {boolean} true if clustering or index processing is in process or loading data, false otherwise
   */
  isInProcess(): boolean {
    return (
      this._loadInProcess || this._clusteringInProcess || this._raiInProcess
    );
  }

  isLoading(): boolean {
    return this._loadInProcess;
  }

  isClustering(): boolean {
    return this._clusteringInProcess;
  }

  isCalculatingRAI(): boolean {
    return this._raiInProcess;
  }
}

type MethodDescription = {
  codename: string;
  layer?: VectorLayer;
  name: string;
  type: string;
};