import { Injectable } from '@angular/core';
import * as _ from 'lodash-es';
import { DashboardData } from './../../../interfaces';

/**
 * Service to prepare line chart data - x, y axes data, lineColor,chartOption data
 */
@Injectable()

/**
 * @class LineChartService
 */
export class LineChartService {

  /**
   * Default method of OrganisationService class
   */
  constructor() { }

  /**
   * Get chart data
   *
   * @param {any} data data
   *
   * @return {object} line chart data
   */
  parseLineChart(data: DashboardData) {
    const chartList = [];
    const groupList = {};
    let i = 0;
    _.forEach(data.bucketData, (bucketData, key) => {
      const groupData: object = {};
      let yAxesLabel: string = data.name;
      let legendLabel = '';

      if (data.series === '') {
        legendLabel = bucketData.name;
        groupData['legend'] = [bucketData.name];

        if (bucketData.time_unit !== undefined) {
          yAxesLabel = bucketData.name + ' (' + bucketData.time_unit + ')';
        } else {
          yAxesLabel = bucketData.name;
        }
      } else {
        groupData['legend'] = data.series;
        legendLabel = data.series[i];
      }
      const chartData = this.getLineData(bucketData);

      // Options
      groupData['options'] = this.getChartOption(yAxesLabel);
      groupData['yAxes'] = [{ data: chartData.values, label: legendLabel }];
      groupData['xAxes'] = chartData.labels;

      if (groupList[bucketData.group_id]) {
        Array.prototype.push.apply(groupList[bucketData.group_id].yAxes, groupData['yAxes']);
      } else {
        groupList[bucketData.group_id] = groupData;
      }

      // Colors
      groupData['colors'] = this.getChartColors(groupList[bucketData.group_id].legend.length);
      i++;
    });

    _.forOwn(groupList, (group: any, groupId) => {
      chartList.push({ yaxesData: group.yAxes, xaxesData: group.xAxes, chartOptions: group.options, chartColors: group.colors });
    });

    return chartList;
  }

  /**
   * Get line chart value and lable
   *
   * @param {any} bucketData line chart value and lable
   */
  getLineData(bucketData: any) {
    const values: Array<any> = [];
    const labels: Array<any> = [];
    _.forEach(bucketData.buckets, (bucketValue, bucketKey) => {
      values.push(bucketValue.value);
      labels.push(bucketValue.key_name);
    });
    return { labels: labels, values: values };
  }

  /**
   * Get chart options
   *
   * @param {string} labelString get chart option
   */
  getChartOption(labelString: string) {
    return {
      legend: { display: true },
      scales: {
        xAxes: [{
          gridLines: { display: false }
        }],
        yAxes: [{
          scaleLabel: { display: true, labelString: labelString },
          ticks: { beginAtZero: true }
        }]
      }
    };
  }

  /**
   * Get line chart color
   *
   * @param {number} legendCount legendCount
   */
  getChartColors(legendCount: number): string[] {
    const colors = ['Red', 'Blue', 'Green'];
    const colorArray = [];
    for (let i = 0; i < legendCount; i++) {
      colorArray.push({
        backgroundColor: colors[i],
        borderColor: colors[i],
        fill: false
      });
    }
    return colorArray;
  }
}