import { BarSerie, BarOptions, Datapoint, Color, ValueX, OpacityFormatter, BarPodType } from '../types';

import * as _ from 'lodash';

export type DataRow = {
  key: number; // x
  data: {
    [serieTarget: string]: {
      values: number[]; // y list
      colors: string[];
      opacity: number[];
    }
  };
  maxSumm: number;
  minSubtraction: number;
}

export class DataProcessor {
  _formattedDataRows: DataRow[];

  constructor(protected series: BarSerie[], protected options: BarOptions) {
    this.setDataRowsForNonDiscreteType();
  }

  public get dataRows(): DataRow[] {
    return this._formattedDataRows;
  }

  protected setDataRowsForDiscreteType(): void {
    const groupByList = (
      this.options.type[BarPodType.DISCRETE].groupBy.x ||
      _.map(_.first(this.series).datapoints, datapoint => datapoint[0])
    );
    let rows = [];
    // TODO: not effective
    for(let groupItem of groupByList) {
      for(let serie of this.series) {
        const datapoint = _.find(serie.datapoints, )
      }
    }
  }

  protected setDataRowsForNonDiscreteType(): void {
    for(let serie of this.series) {
      const rows = _.map(serie.datapoints, (datapoint: Datapoint) => {
        const values = _.tail(datapoint);
        return {
          key: datapoint[0], // x
          data: {
            [serie.target]: {
              values, // y list
              colors: this.getColorsForEachValue(values, serie.color, datapoint[0], serie.target),
              opacity: this.getOpacityForEachValue(values, serie.opacityFormatter, datapoint[0], serie.target),
            }
          },
          maxSumm: this.getMaxSumm(values), // max y axis scale
          minSubtraction: this.getMinSubtraction(values), // min y axis scale
        }
      });
      this._formattedDataRows = _.concat(this._formattedDataRows, rows);
    }
    this._formattedDataRows = _.sortBy(this._formattedDataRows, 'key');
  }

  getColorsForEachValue(values: number[], color: Color, key: ValueX, target: string): string[] {
    if(_.isString(color)) {
      return _.map(values, value => color);
    }
    if(_.isArray(color)) {
      return _.map(values, (value, i) => color[i] || 'red');
    }
    if(_.isFunction(color)) {
      return _.map(values, (value, i) => (color as Function)({ value, barIndex: i, key, target }));
    }
    throw new Error(`Unknown type of serie color: ${target} ${color}`);
  }

  getOpacityForEachValue(values: number[], opacity: OpacityFormatter | undefined, key: ValueX, target: string): number[] {
    if(opacity === undefined) {
      return _.map(values, value => 1);
    }
    return _.map(values, (value, i) => opacity({ value, barIndex: i, key, target })); 
  }

  getMaxSumm(values: number[]): number {
    return values.reduce((prev, curr) => curr > 0 ? prev + curr : prev, 0);
  }

  getMinSubtraction(values: number[]): number {
    return values.reduce((prev, curr) => curr < 0 ? prev + curr : prev, 0);
  }
}