private TimeSpan CalculateTimeCost(StationLineEntityExtender from, StationLineEntityExtender to, List <StationLineEntityExtender> stationLineListCache)
{
// Get 'to' previous station lines, and find the station which is the same as the 'from'
List <StationLineEntityExtender> toPreviousStationLineList = new List <StationLineEntityExtender>();
toPreviousStationLineList.Add(to);
toPreviousStationLineList.AddRange(to.PreviousStationLineList.Select(sl => Convert(sl, stationLineListCache)).ToList());
Stack <StationLineEntityExtender> fromFromToToStationLineStack = new Stack <StationLineEntityExtender>();
foreach (StationLineEntityExtender toPreviousStationLine in toPreviousStationLineList)
{
if (toPreviousStationLine.Station != from.Station)
{
fromFromToToStationLineStack.Push(toPreviousStationLine);
}
else
{
fromFromToToStationLineStack.Push(toPreviousStationLine);
break;
}
}
if (from.Station != fromFromToToStationLineStack.Peek().Station)
{
throw new Exception("From 'from' to 'to' is not in the same line");
}
// Calculate the time from 'from' to 'to'
StationLineEntityExtender transferedLine = fromFromToToStationLineStack.Peek();
bool isTransfered = (from != transferedLine);
TimeSpan transferTimeCost = new TimeSpan();
if (isTransfered)
{
List <MetroTransferEntity> toMetroTransferList = from.TransferToList;
MetroTransferEntity metroTransfer = toMetroTransferList.Find(mt => Convert(mt.ToStationLine, stationLineListCache) == transferedLine);
if (metroTransfer == null)
{
throw new Exception("Cannot find the transfer data");
}
transferTimeCost = metroTransfer.TimeTransfer + new TimeSpan(transferedLine.TimeWait.Ticks / 2);
}
TimeSpan arrivedTimeCost = new TimeSpan();
fromFromToToStationLineStack.Pop(); // no need to check the first line, if it is transfered, we have already calculated. if not, the arrive time is zero.
while (fromFromToToStationLineStack.Count > 0)
{
StationLineEntity stationline = fromFromToToStationLineStack.Pop();
arrivedTimeCost += stationline.TimeArrived;
}
return(transferTimeCost + arrivedTimeCost);
}
private List <MetroTransferEntity> SeachMetroTransferByFromStationLineIdQuery(int stationLineId)
{
List <MetroTransfer> matchedMetroTransferList =
metroWeb.MetroWebDatabase.Table <MetroTransfer>().Select(new MetroTransfer {
FromStationLineId = stationLineId
});
if (matchedMetroTransferList.Count == 0)
{
throw new Exception(string.Format("The from station line id {0} is not found.", stationLineId));
}
List <MetroTransferEntity> matchedMetroTransferEntityList = new List <MetroTransferEntity>();
foreach (MetroTransfer matchedMetroTransfer in matchedMetroTransferList)
{
if (!metroTransferEntityList.Exists(metroTransfer => metroTransfer.TransferId == matchedMetroTransfer.TransferId))
{
MetroTransferEntity matchedMetroTransferEntity = new MetroTransferEntity(metroWeb, matchedMetroTransfer);
matchedMetroTransferEntityList.Add(matchedMetroTransferEntity);
}
}
return(matchedMetroTransferEntityList);
}
internal bool FullyGetRoute(StationEntity fromStation, List <StationLineEntityExtender> stationLineListCache, TimeSpan arrivedTimeLimit, Stack <StationLineEntityExtender> stationLineExtenderStatck)
{
// if current StationLine is the from staiton, return true
if (this.Station == fromStation)
{
MinimumTime = new TimeSpan(TimeWait.Ticks / 2);
MinimumRoute.Clear();
MinimumRoute.Add(this);
return(true);
}
// if current stationline is the end station, return false
StationLineEntityExtender previousStationLineExtender = null;
if (this.PreviousStationLine != null)
{
previousStationLineExtender = Convert(this.PreviousStationLine, stationLineListCache);
if (stationLineExtenderStatck.Contains(previousStationLineExtender)) // avoid death loop
{
previousStationLineExtender = null;
}
}
List <StationLineEntityExtender> transferStationLineExtenderList = this.TransferFromList.Select(
metroTransfer => Convert(metroTransfer.FromStationLine, stationLineListCache)).ToList(); // todo: this may return duplicate stationlines
for (int i = transferStationLineExtenderList.Count - 1; i >= 0; i--) // avoid death loop
{
if (stationLineExtenderStatck.Contains(transferStationLineExtenderList[i]))
{
transferStationLineExtenderList.RemoveAt(i);
}
}
if (previousStationLineExtender == null && transferStationLineExtenderList.Count == 0)
{
return(false);
}
// if the previouStationLine is not the 'from' station, and the minmimum arrived time is greater than newArrivedTimeLimit, so we don't need to go further
bool finalResult = false;
if (previousStationLineExtender != null)
{
TimeSpan newArrivedTimeLimit = arrivedTimeLimit - this.TimeArrived;
TimeSpan previousStationLineArrivedMin = previousStationLineExtender.TimeArrived;
foreach (MetroTransferEntity metroTransfer in previousStationLineExtender.TransferFromList)
{
if (Convert(metroTransfer.ToStationLine, stationLineListCache) == previousStationLineExtender)
{
TimeSpan transferCost = metroTransfer.TimeTransfer + new TimeSpan(previousStationLineExtender.TimeWait.Ticks / 2);
previousStationLineArrivedMin = previousStationLineArrivedMin > transferCost ? transferCost : previousStationLineArrivedMin;
}
}
if (previousStationLineExtender.Station == fromStation || previousStationLineArrivedMin <= newArrivedTimeLimit)
{
// get previous station FullyGetRoute
stationLineExtenderStatck.Push(this);
previousStationLineExtender.TransferTimes = this.TransferTimes;
bool found = previousStationLineExtender.FullyGetRoute(fromStation, stationLineListCache, newArrivedTimeLimit, stationLineExtenderStatck);
stationLineExtenderStatck.Pop();
if (found)
{
// compare whether current route is the minimum route
TimeSpan arriveTimeCost = previousStationLineExtender.MinimumTime + TimeArrived;
if (arriveTimeCost < MinimumTime)
{
MinimumTime = arriveTimeCost;
MinimumRoute = new List <StationLineEntity>(previousStationLineExtender.MinimumRoute);
MinimumRoute.Add(this);
}
finalResult = true;
}
}
}
// if we have already been transfered 4 times, we don't need to transfer any more because it is definitly not the nearest route
if (TransferTimes < 5)
{
// if the transferStation is not the 'from' station, and the minmimum arrived time is greater than newArrivedTimeLimit, so we don't need to go further
foreach (StationLineEntityExtender transferStationLine in transferStationLineExtenderList)
{
List <MetroTransferEntity> toMetroTransferList = transferStationLine.TransferToList;
MetroTransferEntity metroTransfer = toMetroTransferList.Find(mt => Convert(mt.ToStationLine, stationLineListCache) == this);
if (metroTransfer == null)
{
throw new Exception("Cannot find the transfer data, something wrong?!");
}
TimeSpan transferTimeCost = metroTransfer.TimeTransfer + new TimeSpan(this.TimeWait.Ticks / 2);
TimeSpan newArrivedTimeLimit = arrivedTimeLimit - transferTimeCost - transferStationLine.TimeArrived;
StationLineEntityExtender transferStationPreviousStationLine = Convert(transferStationLine.PreviousStationLine, stationLineListCache);
TimeSpan transferStationLineArrivedMin = transferStationPreviousStationLine.TimeArrived;
foreach (MetroTransferEntity transferMetroTransfer in transferStationPreviousStationLine.TransferFromList)
{
if (Convert(metroTransfer.ToStationLine, stationLineListCache) == transferStationLine)
{
TimeSpan transferCost = transferMetroTransfer.TimeTransfer + new TimeSpan(transferStationLine.TimeWait.Ticks / 2);
transferStationLineArrivedMin = transferStationLineArrivedMin > transferCost ? transferCost : transferStationLineArrivedMin;
}
}
if (transferStationPreviousStationLine.Station == fromStation || transferStationLineArrivedMin <= newArrivedTimeLimit)
{
// get transfer station
stationLineExtenderStatck.Push(this);
transferStationPreviousStationLine.TransferTimes = this.TransferTimes + 1;
bool found = transferStationPreviousStationLine.FullyGetRoute(fromStation, stationLineListCache, newArrivedTimeLimit, stationLineExtenderStatck);
stationLineExtenderStatck.Pop();
if (found)
{
// compare whether current route is the minimum route
TimeSpan arriveTimeCost = transferStationPreviousStationLine.MinimumTime + TimeArrived + transferTimeCost;
if (arriveTimeCost < MinimumTime)
{
MinimumTime = arriveTimeCost;
MinimumRoute = new List <StationLineEntity>(transferStationPreviousStationLine.MinimumRoute);
MinimumRoute.Add(transferStationLine);
}
finalResult = true;
}
}
}
}
return(finalResult);
}
