almus-d3-graph/lib/components/link/link.helper.js

React component to build interactive and configurable graphs with d3 effortlessly

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.buildLinkPathDefinition = undefined;

var _RADIUS_STRATEGIES;

var _link = require("./link.const");

function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; } /**
                                                                                                                                                                                                                   * @module Link/helper
                                                                                                                                                                                                                   * @description
                                                                                                                                                                                                                   * A set of helper methods to manipulate/create links.
                                                                                                                                                                                                                   */


/**
 * Computes radius value for a straight line.
 * @returns {number} radius for straight line.
 * @memberof Link/helper
 */
function straightLineRadius() {
  return 0;
}

/**
 * Computes radius for a smooth curve effect.
 * @param {number} x1 - x value for point 1
 * @param {number} y1 - y value for point 1
 * @param {number} x2 - y value for point 2
 * @param {number} y2 - y value for point 2
 * @returns{number} value of radius.
 * @memberof Link/helper
 */
function smoothCurveRadius(x1, y1, x2, y2) {
  var dx = x2 - x1;
  var dy = y2 - y1;

  return Math.sqrt(dx * dx + dy * dy);
}

/**
 * Computes radius value for a full curve (semi circumference).
 * @returns {number} radius for full curve.
 * @memberof Link/helper
 */
function fullCurveRadius() {
  return 1;
}

var RADIUS_STRATEGIES = (_RADIUS_STRATEGIES = {}, _defineProperty(_RADIUS_STRATEGIES, _link.LINE_TYPES.STRAIGHT, straightLineRadius), _defineProperty(_RADIUS_STRATEGIES, _link.LINE_TYPES.CURVE_SMOOTH, smoothCurveRadius), _defineProperty(_RADIUS_STRATEGIES, _link.LINE_TYPES.CURVE_FULL, fullCurveRadius), _RADIUS_STRATEGIES);

/**
 * Get a strategy to compute line radius.<br/>
 * *CURVE_SMOOTH* type inspired by {@link http://bl.ocks.org/mbostock/1153292|mbostock - Mobile Patent Suits}.
 * @param {string} [type=LINE_TYPES.STRAIGHT] type of curve to get radius strategy from.
 * @returns {Function} a function that calculates a radius
 * to match curve type expectation. Fallback is the straight line.
 * @memberof Link/helper
 */
function getRadiusStrategy(type) {
  return RADIUS_STRATEGIES[type] || RADIUS_STRATEGIES[_link.LINE_TYPES.STRAIGHT];
}

/**
 * This method returns the path definition for a given link base on the line type
 * and the link source and target.
 * {@link https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/d|d attribute mdn}
 * @param {Object} link - the link to build the path definition
 * @param {Object} link.source - link source
 * @param {Object} link.target - link target
 * @param {string} type - the link line type
 * @returns {string} the path definition for the requested link
 * @memberof Link/helper
 */
function buildLinkPathDefinition(_ref) {
  var _ref$source = _ref.source,
      source = _ref$source === undefined ? {} : _ref$source,
      _ref$target = _ref.target,
      target = _ref$target === undefined ? {} : _ref$target;
  var type = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : _link.LINE_TYPES.STRAIGHT;
  var sx = source.x,
      sy = source.y;
  var tx = target.x,
      ty = target.y;

  var validType = _link.LINE_TYPES[type] || _link.LINE_TYPES.STRAIGHT;
  var radius = getRadiusStrategy(validType)(sx, sy, tx, ty);

  return "M" + sx + "," + sy + "A" + radius + "," + radius + " 0 0,1 " + tx + "," + ty;
}

exports.buildLinkPathDefinition = buildLinkPathDefinition;