private static void TraceToSource(Bus FromBus, Bus BusThatStartedItAll, HashSet <Bus> busesInThisTrace, HashSet <Bus> busesOnPath)
{
//start at FromBus, take a step away from FromBus.
//If we're at the source, add the path that we took to BusesOnRouteToSource.
//If we're at a dead-end, then stop tracing this branch.
//If we hit a bus that's already on the route, then terminate and add the branch.
var connectedBuses = FromBus.ConnectedTo.OfType <Line>().Select(line => line.ConnectedTo.OfType <Bus>().Except(FromBus.Yield()).Single()) //all the buses neighbouring this one
.Except(busesInThisTrace) //exclude any buses we've already touched in this trace
;
foreach (var bus in connectedBuses)
{
if (busesOnPath.Contains(bus)) //we're connected to the target bus. no further processing required on this branch.
{
busesOnPath.UnionWith(busesInThisTrace.Except(BusThatStartedItAll.Yield()));
continue;
}
else
{
//keep searching!
HashSet <Bus> NextStepTraceList;
if (connectedBuses.Count() == 1) //if this is the only possible way forward, then just keep using the same thingy.
{
NextStepTraceList = busesInThisTrace;
}
else
{
NextStepTraceList = new HashSet <Bus>(busesInThisTrace);
}
NextStepTraceList.Add(bus);
TraceToSource(bus, BusThatStartedItAll, NextStepTraceList, busesOnPath);
}
}
}
/// <summary>
/// Obtains a list of all buses directly or indirectly connected to <paramref name="FromBus"/>,
/// so long as they are connected in a fashion that does not rely upon the presence of any elements of
/// <paramref name="BusesToExclude"/>
/// </summary>
/// <param name="FromBus">The <see cref="Bus"/> to trace from.</param>
/// <param name="BusesToExclude">A set of <see cref="Bus"/>es that should be avoided in the trace operation.</param>
/// <returns>A list of all buses directly or indirectly connected to <paramref name="FromBus"/>,
/// so long as connection is not through any element in <paramref name="BusesToExclude"/>.</returns>
public static IEnumerable<Bus> TraceWithoutCrossingBuses(Bus FromBus, IEnumerable<Bus> BusesToExclude)
{
var BusesInTrace = new HashSet<Bus>(FromBus.Yield());
var BusesInPath = new HashSet<Bus>();
_traceWithoutCrossingBuses(FromBus, new HashSet<Bus>(BusesToExclude), BusesInTrace, BusesInPath);
BusesInPath.Add(FromBus);
return BusesInPath;
}
/// <summary>
/// Obtains a list of all buses directly or indirectly connected to <paramref name="FromBus"/>,
/// so long as they are connected in a fashion that does not rely upon the presence of any elements of
/// <paramref name="BusesToExclude"/>
/// </summary>
/// <param name="FromBus">The <see cref="Bus"/> to trace from.</param>
/// <param name="BusesToExclude">A set of <see cref="Bus"/>es that should be avoided in the trace operation.</param>
/// <returns>A list of all buses directly or indirectly connected to <paramref name="FromBus"/>,
/// so long as connection is not through any element in <paramref name="BusesToExclude"/>.</returns>
public static IEnumerable <Bus> TraceWithoutCrossingBuses(Bus FromBus, IEnumerable <Bus> BusesToExclude)
{
var BusesInTrace = new HashSet <Bus>(FromBus.Yield());
var BusesInPath = new HashSet <Bus>();
_traceWithoutCrossingBuses(FromBus, new HashSet <Bus>(BusesToExclude), BusesInTrace, BusesInPath);
BusesInPath.Add(FromBus);
return(BusesInPath);
}
/// <summary>
/// Obtains a list of all buses that are directly on-route from
/// <paramref name="FromBus"/> to <paramref name="TargetBus"/>.
/// </summary>
/// <param name="FromBus">The <see cref="Bus"/> to trace from.</param>
/// <param name="TargetBus">The <see cref="Bus"/> to trace to.</param>
/// <returns>A list of all buses that are directly on-route from
/// <paramref name="FromBus"/> to <paramref name="TargetBus"/> (inclusive).</returns>
public static IEnumerable<Bus> BusesOnRouteToTarget(Bus FromBus, Bus TargetBus)
{
//start at FromBus, take a step away from FromBus.
//If we're at the source, add the path that we took to BusesOnRouteToSource.
//If we're at a dead-end, then stop tracing this branch.
//If we hit a bus that's already on the route, then terminate and add the branch.
HashSet<Bus> results = new HashSet<Bus>(TargetBus.Yield());
HashSet<Bus> thisTrace = new HashSet<Bus>(FromBus.Yield());
TraceToSource(FromBus, FromBus, thisTrace, results);
results.Add(FromBus);
return (IEnumerable<Bus>)results;
}
/// <summary>
/// Obtains a list of all buses that are directly on-route from
/// <paramref name="FromBus"/> to <paramref name="TargetBus"/>.
/// </summary>
/// <param name="FromBus">The <see cref="Bus"/> to trace from.</param>
/// <param name="TargetBus">The <see cref="Bus"/> to trace to.</param>
/// <returns>A list of all buses that are directly on-route from
/// <paramref name="FromBus"/> to <paramref name="TargetBus"/> (inclusive).</returns>
public static IEnumerable <Bus> BusesOnRouteToTarget(Bus FromBus, Bus TargetBus)
{
//start at FromBus, take a step away from FromBus.
//If we're at the source, add the path that we took to BusesOnRouteToSource.
//If we're at a dead-end, then stop tracing this branch.
//If we hit a bus that's already on the route, then terminate and add the branch.
HashSet <Bus> results = new HashSet <Bus>(TargetBus.Yield());
HashSet <Bus> thisTrace = new HashSet <Bus>(FromBus.Yield());
TraceToSource(FromBus, FromBus, thisTrace, results);
results.Add(FromBus);
return((IEnumerable <Bus>)results);
}
private static void TraceToSource(Bus FromBus, Bus BusThatStartedItAll, HashSet<Bus> busesInThisTrace, HashSet<Bus> busesOnPath)
{
//start at FromBus, take a step away from FromBus.
//If we're at the source, add the path that we took to BusesOnRouteToSource.
//If we're at a dead-end, then stop tracing this branch.
//If we hit a bus that's already on the route, then terminate and add the branch.
var connectedBuses = FromBus.ConnectedTo.OfType<Line>().Select(line => line.ConnectedTo.OfType<Bus>().Except(FromBus.Yield()).Single()) //all the buses neighbouring this one
.Except(busesInThisTrace) //exclude any buses we've already touched in this trace
;
foreach (var bus in connectedBuses)
{
if (busesOnPath.Contains(bus)) //we're connected to the target bus. no further processing required on this branch.
{
busesOnPath.UnionWith(busesInThisTrace.Except(BusThatStartedItAll.Yield()));
continue;
}
else
{
//keep searching!
HashSet<Bus> NextStepTraceList;
if (connectedBuses.Count() == 1) //if this is the only possible way forward, then just keep using the same thingy.
{
NextStepTraceList = busesInThisTrace;
}
else
{
NextStepTraceList = new HashSet<Bus>(busesInThisTrace);
}
NextStepTraceList.Add(bus);
TraceToSource(bus, BusThatStartedItAll, NextStepTraceList, busesOnPath);
}
}
}
/// <summary>
/// Traces from <paramref name="FromBus"/> along all buses in <paramref name="AllowedBuses"/>,
/// and executing <paramref name="Callback"/> for every connection between two buses.
/// </summary>
/// <param name="FromBus">The bus to trace from.</param>
/// <param name="AllowedBuses">All buses that are to be allowed in the trace.</param>
/// <param name="Callback">A custom action to execute for every connection.</param>
public static void TraceFromWithCallback(Bus FromBus, IEnumerable<Bus> AllowedBuses, Action<Bus, Line, Bus> Callback)
{
HashSet<Bus> thisTrace = new HashSet<Bus>(FromBus.Yield());
_traceFromWithCallback(FromBus, AllowedBuses, thisTrace, Callback);
}
private static void _traceWithoutCrossingBuses(Bus FromBus, HashSet<Bus> ExcludeList, HashSet<Bus> busesInThisTrace, HashSet<Bus> busesOnPath)
{
var connectedBuses = FromBus.ConnectedTo.OfType<Line>().Select(line => line.ConnectedTo.OfType<Bus>().Except(FromBus.Yield()).Single()) //all the buses neighbouring this one
.Except(busesInThisTrace) //exclude any buses we've already touched in this trace
;
if (connectedBuses.Count() == 0)
{
busesOnPath.UnionWith(busesInThisTrace);
return;
}
foreach (var bus in connectedBuses)
{
if (ExcludeList.Contains(bus)) //we're connected to the target bus. end the thread.
{
continue;
}
else
{
//keep searching!
HashSet<Bus> NextStepTraceList;
if (connectedBuses.Count() == 1) //if this is the only possible way forward, then just keep using the same thingy.
{
NextStepTraceList = busesInThisTrace;
}
else
{
NextStepTraceList = new HashSet<Bus>(busesInThisTrace);
}
NextStepTraceList.Add(bus);
_traceWithoutCrossingBuses(bus, ExcludeList, NextStepTraceList, busesOnPath);
}
}
}
private static void _traceFromWithCallback(Bus FromBus, IEnumerable<Bus> AllowedBuses, HashSet<Bus> busesInThisTrace, Action<Bus, Line, Bus> Callback)
{
var connectedBuses = FromBus.ConnectedTo.OfType<Line>().Select(line => Tuple.Create(line, line.ConnectedTo.OfType<Bus>().Except(FromBus.Yield()).Single())) //all the buses neighbouring this one
.Where(t => !busesInThisTrace.Contains(t.Item2) && AllowedBuses.Contains(t.Item2)) //exclude any buses we've already touched in this trace, and any buses that aren't in the allowed set.
;
foreach (var bus in connectedBuses)
{
Callback(FromBus, bus.Item1, bus.Item2);
//keep searching!
HashSet<Bus> NextStepTraceList = connectedBuses.Count() == 1 ? busesInThisTrace : new HashSet<Bus>(busesInThisTrace);
NextStepTraceList.Add(bus.Item2);
_traceFromWithCallback(bus.Item2, AllowedBuses, NextStepTraceList, Callback);
}
}
private static void _traceWithoutCrossingBuses(Bus FromBus, HashSet <Bus> ExcludeList, HashSet <Bus> busesInThisTrace, HashSet <Bus> busesOnPath)
{
var connectedBuses = FromBus.ConnectedTo.OfType <Line>().Select(line => line.ConnectedTo.OfType <Bus>().Except(FromBus.Yield()).Single()) //all the buses neighbouring this one
.Except(busesInThisTrace) //exclude any buses we've already touched in this trace
;
if (connectedBuses.Count() == 0)
{
busesOnPath.UnionWith(busesInThisTrace);
return;
}
foreach (var bus in connectedBuses)
{
if (ExcludeList.Contains(bus)) //we're connected to the target bus. end the thread.
{
continue;
}
else
{
//keep searching!
HashSet <Bus> NextStepTraceList;
if (connectedBuses.Count() == 1) //if this is the only possible way forward, then just keep using the same thingy.
{
NextStepTraceList = busesInThisTrace;
}
else
{
NextStepTraceList = new HashSet <Bus>(busesInThisTrace);
}
NextStepTraceList.Add(bus);
_traceWithoutCrossingBuses(bus, ExcludeList, NextStepTraceList, busesOnPath);
}
}
}
private static void _traceFromWithCallback(Bus FromBus, IEnumerable <Bus> AllowedBuses, HashSet <Bus> busesInThisTrace, Action <Bus, Line, Bus> Callback)
{
var connectedBuses = FromBus.ConnectedTo.OfType <Line>().Select(line => Tuple.Create(line, line.ConnectedTo.OfType <Bus>().Except(FromBus.Yield()).Single())) //all the buses neighbouring this one
.Where(t => !busesInThisTrace.Contains(t.Item2) && AllowedBuses.Contains(t.Item2)) //exclude any buses we've already touched in this trace, and any buses that aren't in the allowed set.
;
foreach (var bus in connectedBuses)
{
Callback(FromBus, bus.Item1, bus.Item2);
//keep searching!
HashSet <Bus> NextStepTraceList = connectedBuses.Count() == 1 ? busesInThisTrace : new HashSet <Bus>(busesInThisTrace);
NextStepTraceList.Add(bus.Item2);
_traceFromWithCallback(bus.Item2, AllowedBuses, NextStepTraceList, Callback);
}
}
/// <summary>
/// Traces from <paramref name="FromBus"/> along all buses in <paramref name="AllowedBuses"/>,
/// and executing <paramref name="Callback"/> for every connection between two buses.
/// </summary>
/// <param name="FromBus">The bus to trace from.</param>
/// <param name="AllowedBuses">All buses that are to be allowed in the trace.</param>
/// <param name="Callback">A custom action to execute for every connection.</param>
public static void TraceFromWithCallback(Bus FromBus, IEnumerable <Bus> AllowedBuses, Action <Bus, Line, Bus> Callback)
{
HashSet <Bus> thisTrace = new HashSet <Bus>(FromBus.Yield());
_traceFromWithCallback(FromBus, AllowedBuses, thisTrace, Callback);
}