NetGeoProv.js Algo

function CachedLocation(loc, cellInfo, wifiList) {
  this.location = loc;
  this.cellInfo = cellInfo;
  this.wifiList = wifiList;
}

CachedLocation.prototype = {
  constructor: CachedLocation,
  isGeoip: function() {
    return !this.cellInfo && !this.wifiList;
  },
  isCellAndWifi: function() {
    return this.cellInfo && this.wifiList;
  },
  isCellOnly: function() {
    return this.cellInfo && !this.wifiList;
  },
  isWifiOnly: function() {
    return this.wifiList && !this.cellInfo;
  },
  //-> if 50% of the SSIDS match
  isWifiApproxEqual: function(wifiList) {
    if (!this.wifiList)
      return false;
  },
  //if fields match and signal is within ?% (who can answer this)
  isCellApproxEqual: function(cellInfo) {
    if (!this.cellInfo)
      return false;
  }
};

var gCachedLocation;

// return null if not better
function getCachedLocIfBetter(newCell, newWifiList)
{
  if (!gCachedLocation)
    return null;

  // if new request has both cell and wifi, and old is just cell
  if (gCachedLocation.isCellOnly() && newCell && newWIfiList) {
    return null;
  }

  // if new is geoip request
  if (!newCell && !newWifiList) {
    return gOldLocation.location;
  }

  var hasEqualCells = false;
  if (newCell) {
    hasEqualCells = gCachedLocation.isCellsApproxEqual(newCell);
  }

  var hasEqualWifis = false;
  if (newWifiList) {
    hasEqualWifis = gCachedLocation.isWifiApproxEqual(newWifiList);
  }

  if (gCachedLocation.isCellOnly()) {
    if (hasEqualCells)
      return gOldLocation.location;
  }
  else if (gCacheLocation.isCellAndWifi()) {
    if ((hasEqualCells && hasEqualWifis) ||
         (!newWifiList && hasEqualCells) ||
          (!newCell && hasEqualWifis)
    {
      return gOldLocation.location;
    }
  }

  return null;
}