/**
 * @fileOverview Venn Diagram
 * @author leungwensen@gmail.com
 */
const GeomBase = require('./base');
const Util = require('../util');
const {
  venn,
  scaleSolution,
  circlePath,
  intersectionAreaPath,
  computeTextCentres
} = require('venn.js');
require('./shape/venn');

class Venn extends GeomBase {
  /**
   * get default configuration
   * @protected
   * @return {Object} configuration
   */
  getDefaultCfg() {
    const cfg = super.getDefaultCfg();
    cfg.type = 'venn';
    cfg.shapeType = 'venn';
    cfg.generatePoints = false;
    // super.draw(data, container, shapeFactory, index);
    return cfg;
  }

  _getAttrValues(attr, record) {
    if (attr.type === 'position') {
      return [ record.x, record.y ];
    }
    return super._getAttrValues(attr, record);
  }

  sets(field) {
    this.set('setsField', field);
    return this;
  }

  _initAttrs() {
    const self = this;
    super._initAttrs();
    const attrOptions = self.get('attrOptions');
    const setsField = self.get('setsField') || 'sets';
    const data = self.get('data');
    const sizeField = attrOptions.size ? attrOptions.size.field : 'size';
    // prepare data
    data.forEach(row => {
      row.sets = row[setsField];
      row._sets = row[setsField].join('&');
      row.size = row[sizeField];
    });
    const solution = venn(data);
    // scaling
    const coord = self.get('coord');
    const xRange = [ Math.min(coord.x.end, coord.x.start), Math.max(coord.x.end, coord.x.start) ];
    const yRange = [ Math.min(coord.y.end, coord.y.start), Math.max(coord.y.end, coord.y.start) ];
    const width = xRange[1] - xRange[0];
    const height = yRange[1] - yRange[0];
    const styleOptions = self.get('styleOptions');
    let padding = styleOptions && Util.isObject(styleOptions.style) ? styleOptions.style.padding : 0;
    if (!Util.isFinite(padding)) {
      padding = 0;
    }
    const circles = scaleSolution(solution, width, height, padding);
    const textCenters = computeTextCentres(circles, data);
    data.forEach(row => {
      const sets = row.sets;
      const id = sets.join(',');
      row.id = id;
      if (sets.length === 1) {
        const circle = circles[id];
        row.path = circlePath(circle.x, circle.y, circle.radius);
        Util.assign(row, circle);
      } else {
        const setCircles = sets.map(set => circles[set]);
        let path = intersectionAreaPath(setCircles);
        if (!/[zZ]$/.test(path)) {
          path += 'Z';
        }
        row.path = path;
        const center = textCenters[id] || { x: 0, y: 0 };
        Util.assign(row, center);
      }
    });
    // x, y scales
    // self.position('x*y');
    // self.scale('x', { type: 'identity' });
    // self.scale('y', { type: 'identity' });
  }

  // createShapePointsCfg(obj) {
  //   const xScale = this.getXScale();
  //   const yScale = this.getYScale();
  //   return {
  //     x: obj[xScale.field],
  //     y: obj[yScale.field],
  //     y0: yScale ? yScale.scale(this.getYMinValue()) : undefined
  //   };
  // }

  // paint() {
  //   super.paint();
  //   const self = this;
  //   const dataArray = self.get('dataArray');
  //   const shapeContainer = self.get('shapeContainer');
  //   // add labels
  //   dataArray.forEach(row => {
  //     const cfg = self.getDrawCfg(row[0]);
  //     const origin = cfg.origin._origin;
  //     shapeContainer.addShape('text', {
  //       attrs: Util.mix({}, {
  //         x: origin.x,
  //         y: origin.y,
  //         text: origin.label || '',
  //         fontSize: 18,
  //         fill: cfg.shape === 'hollow' ? cfg.color : '#666',
  //         textAlign: 'center',
  //         textBaseline: 'middle'
  //       }, cfg.style ? cfg.style.textStyle : {})
  //     });
  //   });
  // }
}

GeomBase.Venn = Venn;

module.exports = Venn;