public void Allocate(Link link)
{
if (state != State.FREE)
throw new ApplicationException("Cannot reserve not free slot");
state = State.TAKEN;
slotOWner = link;
}
public void AllocatePath(Link link)
{
if (currCapacity < link.capacityNeeded)
throw new ApplicationException("cannot allocate link!");
if (allocatedLinks.Exists(x => x == link))
throw new ApplicationException("link already exists!");
allocatedLinks.Add(link);
currCapacity -= link.capacityNeeded;
}
public void AllocateSlot(Link link, int slot)
{
List<int> neededSlots = GetNeededSlotsForLinkAndBeginPosition(link, slot);
foreach(int slotNo in neededSlots) //TODO: refactor - use .foreach
{
if (!slots[slotNo].IsAvailable())
throw new ApplicationException("cannot allocate taken slot");
slots[slotNo].Allocate(link);
}
}
public void DeallocatePath(Link link)
{
if (!allocatedLinks.Remove(link))
throw new ApplicationException("link not exists!");
currCapacity += link.capacityNeeded;
}
public void DeallocateSlot(Link link, int slot)
{
List<int> neededSlots = GetNeededSlotsForLinkAndBeginPosition(link, slot);
neededSlots.ForEach(x => slots[x].Deallocate());
}
private List<Connection> FindShortestReversedPathForLinkAndGivenDestination(Link link, Device source, Device destination)
{
Device currDev = destination;
List<Connection> path = new List<Connection>();
while (currDev != source)
{
Connection currPath = currDev.outgoingConnections.Find(x => x.destination.mark == currDev.mark - 1);
if (currPath == null)
throw new ApplicationException("dsadsads");
path.Add(currPath);
currDev = currPath.destination;
}
path.Reverse();
return path;
}
private void ValidateLinkPaths(Link link)
{
VerifyPathsSize(link);
VerifyPathsSourceAndDestination(link);
CheckPathsConsistency(link);
CheckIfLinkIsAllocatedOnAllItsPathConnections(link);
CheckIfEveryConnectionInWholePathIsUnique(link);
}
private static void VerifyPathsSize(Link link)
{
if (link.mainPath.Count == 0)
throw new PathValidationException("Path size is 0!");
if (link.additionalDestinationPaths.Count != link.additionalDestinations.Count)
throw new PathValidationException("Not all additional destination paths are calculated");
if (link.additionalDestinationPaths.Any(x => x.Count == 0))
throw new PathValidationException("Additional destination path size is 0!");
if (link.additionalSourcePaths.Count != link.additionalSourcePaths.Count)
throw new PathValidationException("Not all additional source paths are calculated");
if (link.additionalSourcePaths.Any(x => x.Count == 0))
throw new PathValidationException("Additional source path size is 0!");
}
private List<Connection> FindShortestPathForLinkAndGivenDestination(Link link, Device source, Device destination)
{
Device currDev = destination;
List<Connection> path = new List<Connection>();
while (currDev != source)
{
Connection currPath = currDev.incomingConnections.Find(x => x.source.mark == currDev.mark - 1);
path.Add(currPath);
currDev = currPath.source;
}
path.Reverse();
return path;
}
private void CheckIfEveryConnectionInWholePathIsUnique(Link link)
{
if (link.wholePath.Distinct().ToList().Count != link.wholePath.Count)
throw new ApplicationException("Whole path connections are not distinct!");
}
private static void CheckIfLinkIsAllocatedOnAllItsPathConnections(Link link)
{
if (!link.wholePath.All(x => x.IsLinkAllocated(link)))
throw new PathValidationException("Path is not allocated on all its connections!");
}
private void AllocateLinkPath(Link link)
{
AllocateMainPath(link);
AllocateAdditionalPaths(link);
ValidateLinkPaths(link);
}
private void AllocateMainPath(Link link)
{
CreateMarksWithBFS(link, link.mainSource);
if (link.mainDestination.mark == NOT_SEEN)
throw new ApplicationException("Path allocation algirithm cannot allocate a link: " + link.name);
if (link.mainPath != null)
throw new ApplicationException("main path should be empty in this moment!");
List<Connection> path = FindShortestPathForLinkAndGivenDestination(link, link.mainSource, link.mainDestination);
path.ForEach(x => x.AllocatePath(link));
link.mainPath = path;
}
private void AllocateAdditionalSourcesPaths(Link link)
{
foreach (Device source in link.additionalSources)
{
CreateMarksWithBFS(link, source);
int minMark = link.devicesOnWholePath.Min(x => x.mark);
if (minMark == int.MaxValue)
throw new ApplicationException("Path allocation algoritithm cannot allocate additional source for link: " + link.name);
Device devWithMinMark = link.devicesOnWholePath.Find(x => x.mark == minMark);
List<Connection> additionalSourcePath =
FindShortestPathForLinkAndGivenDestination(link, source, devWithMinMark);
additionalSourcePath.ForEach(x => x.AllocatePath(link));
link.additionalSourcePaths.Add(additionalSourcePath);
}
}
private void AllocateAdditionalPaths(Link link)
{
AllocateAdditionalSourcesPaths(link);
AllocateAdditionalDestinationPaths(link);
}
private static void VerifyPathsSourceAndDestination(Link link)
{
VerifyPathSource(link.mainPath, link.mainSource);
VerifyPathDestination(link.mainPath, link.mainDestination);
for (int i = 0; i < link.additionalSources.Count; i++)
{
VerifyPathSource(link.additionalSourcePaths[i], link.additionalSources[i]);
}
for (int i = 0; i < link.additionalDestinations.Count; i++)
{
VerifyPathDestination(link.additionalDestinationPaths[i], link.additionalDestinations[i]);
}
}
/// <summary>
///
/// </summary>
/// <param name="link"></param>
/// <param name="slot"></param>
/// <returns>EMPTY LIST MEANS IMPOSSIBLE - BUGFIX</returns>
public List<int> GetNeededSlotsForLinkAndBeginPosition(Link link, int slot)
{
int currSlot = slot * maxCapacity / link.maxCapacityOnPath;
int currModulo = slots.Count;
int currConnectionModuloForLink = maxCapacity / link.capacityNeeded;
int noOfAllocatedSlots = currModulo / currConnectionModuloForLink;
List<int> neededSlots = new List<int>();
for (int i = currSlot; i < currModulo; i += currConnectionModuloForLink)
{
neededSlots.Add(i);
}
return neededSlots;
}
public bool CanAllocateLink(Link link)
{
return currCapacity >= link.capacityNeeded;
}
public bool IsLinkAllocated(Link link)
{
return allocatedLinks.Any(x => x == link);
}
/// <summary>
/// Comparation in decreasing order of capacity needed and then in dst.name order.
/// </summary>
/// <param name="lhs"></param>
/// <param name="rhs"></param>
/// <returns></returns>
public int LinkCmp(Link lhs, Link rhs)
{
if (lhs.capacityNeeded > rhs.capacityNeeded) return -1;
if (lhs.capacityNeeded < rhs.capacityNeeded) return 1;
return String.CompareOrdinal(rhs.mainDestination.name, lhs.mainDestination.name);
}
private void CheckNumberOfAllocatedSlots(Link link)
{
foreach (Connection connection in link.mainPath)
{
int neededSlotsOnConnection = link.capacityNeeded / connection.CapacityPerSlot;
int slotsAllocatedOnConnection = connection.slots.Count(x => x.slotOWner == link);
if (neededSlotsOnConnection != slotsAllocatedOnConnection)
throw new PathValidationException("Slots number allocated on connection is wrong");
}
}
private static void CheckPathsConsistency(Link link)
{
CheckPathConsistency(link.mainPath);
link.additionalSourcePaths.ForEach(CheckPathConsistency);
link.additionalDestinationPaths.ForEach(CheckPathConsistency);
}
public bool CanAllocateSlot(Link link, int slot)
{
List<int> neededSlots = GetNeededSlotsForLinkAndBeginPosition(link, slot);
return CanAllocateSlots(neededSlots);
}
/// <summary>
/// reversed BFS uses one-way links in reversed direction
/// (uses incoming connections instead of outgoing connections)
/// </summary>
/// <param name="link"></param>
/// <param name="destination"></param>
private void CreateMarksWithReversedBFS(Link link, Device startPoint)
{
Queue<Device> frontier = new Queue<Device>();
frontier.Enqueue(startPoint);
ResetMarks(NOT_SEEN);
startPoint.mark = START_POINT;
while (frontier.Count != 0)
{
Device curr = frontier.Dequeue();
foreach (Connection c in curr.incomingConnections)
{
if (c.source.mark == NOT_SEEN && c.CanAllocateLink(link))
{
c.source.mark = curr.mark + 1;
frontier.Enqueue(c.source);
}
}
}
}
