mutables

/****************
 * Mutable Objects
 * (despite https://groups.google.com/d/msg/google-earth-engine-developers/ZWxQsCiJhQY/x4b-7vKYAwAJ)
 * 
 * Author: Rodrigo E. Principe
 * email: fitoprincipe82@gmail.com
 * licence: MIT
 ****************/
var tools = require('users/fitoprincipe/geetools:tools')

var Feature = function(feature) {
  this.feature = feature
  this.set = function(key, value) {
    this.feature = this.feature.set(key, value)
  }
  this.get = function(property) {
    return this.feature.get(property)
  }
  this.id = this.feature.id()
}
exports.Feature = Feature

var FeatureCollection = function(collection) {
  this.collection = collection
  
  this.setPosition = function(position, property, value) {
    var featlist = this.collection.toList(this.collection.size())
    var feat = ee.Feature(featlist.get(position))
    this.set(feat, property, value)
  }
  
  this.getPosition = function(position, property) {
    var featlist = this.collection.toList(this.collection.size())
    var feat = ee.Feature(featlist.get(position))
    return this.get(feat, property)
  }
  
  this.set = function(feature, property, value) {
    var fid = feature.id() // string
    var newft = this.collection.map(function(feat) {
      feat = ee.Feature(feat)
      var featid = feat.id()
      var cond = fid.compareTo(featid).eq(0)
      return ee.Feature(ee.Algorithms.If(cond, 
      feat.set(property, value), feat))
    })
    this.collection = newft
  }
  
  this.get = function(feature, property) {
    var fid = feature.id() // string
    var feat = ee.Feature(this.collection.filterMetadata('system:index', 'equals', fid).first())
    return feat.get(property)
  }
  
}
exports.FeatureCollection = FeatureCollection