/**
* Created by gavorhes on 12/23/2015.
*/
import provide from '../util/provide';
let nm = provide('olHelpers');
/**
* take an array of features and sort by a given property name
*/
class SortedFeatures {
/**
*
* @param {Array} features array of ol features
* @param {string} propertyName - the property name to use for lookup
*/
constructor(features, propertyName) {
this.sortedFeatures = features;
this.propertyName = propertyName;
if (this.sortedFeatures.length > 0) {
this._propertyType = typeof this.sortedFeatures[0].getProperties()[this.propertyName];
let _this = this;
this.sortedFeatures.sort(function (a, b) {
if (_this._propertyType == 'number'){
return (a['getProperties']()[_this.propertyName] - b['getProperties']()[_this.propertyName]);
} else if (_this._propertyType == 'string'){
return (a['getProperties']()[_this.propertyName] > b['getProperties']()[_this.propertyName]);
}
});
}
}
/**
* recursive search to find the value
* @param {number|string} propertyValue - the property value to search for
* @param {boolean} [exactMatch=false] if only an exact match should be returned
* @param {Array} [sortedFeatures=this.sortedFeatures] - the candidate features
* @returns {ol.Feature|undefined} the feature matching the lookup
*/
getFeature(propertyValue, exactMatch, sortedFeatures) {
if (typeof sortedFeatures == 'undefined'){
sortedFeatures = this.sortedFeatures;
}
if (typeof exactMatch !== 'boolean'){
exactMatch = false;
}
if (sortedFeatures.length == 0){
return undefined;
}
if (sortedFeatures.length == 1){
if (exactMatch){
if (sortedFeatures[0].getProperties()[this.propertyName] == propertyValue){
return sortedFeatures[0];
} else {
return undefined;
}
} else {
return sortedFeatures[0];
}
}
let lowProp = sortedFeatures[0].getProperties()[this.propertyName];
let highProp = sortedFeatures[sortedFeatures.length - 1].getProperties()[this.propertyName];
if (exactMatch){
if (lowProp == propertyValue){
return sortedFeatures[0];
} else if (propertyValue < lowProp){
return undefined;
} else if (highProp == propertyValue){
return sortedFeatures[sortedFeatures.length - 1];
} else if (propertyValue > highProp){
return undefined;
}
} else {
if (propertyValue <= lowProp){
return sortedFeatures[0];
} else if (propertyValue >= highProp){
return sortedFeatures[sortedFeatures.length - 1];
}
}
let midIndex = Math.floor(sortedFeatures.length / 2);
let midFeature = sortedFeatures[midIndex];
let midProperty = midFeature.getProperties()[this.propertyName];
if (midProperty === propertyValue){
return midFeature;
}
if (propertyValue < midProperty){
return this.getFeature(propertyValue, exactMatch, sortedFeatures.slice(0, midIndex));
} else {
return this.getFeature(propertyValue, exactMatch, sortedFeatures.slice(midIndex));
}
}
}
nm.SortedFeatures = SortedFeatures;
export default SortedFeatures;