| | | 1 | | using System.Collections.Generic; |
| | | 2 | | using System.Linq; |
| | | 3 | | using Itinero.Network.Enumerators.Edges; |
| | | 4 | | |
| | | 5 | | namespace Itinero.Network.Restrictions; |
| | | 6 | | |
| | | 7 | | /// <summary> |
| | | 8 | | /// Contains extension methods to work with restricted sequences. |
| | | 9 | | /// </summary> |
| | | 10 | | public static class RestrictionExtensions |
| | | 11 | | { |
| | | 12 | | /// <summary> |
| | | 13 | | /// Inverts the given restriction returning all possible sequences in the network starting with the same edges excep |
| | | 14 | | /// </summary> |
| | | 15 | | /// <param name="restrictedSequence">The restricted sequence.</param> |
| | | 16 | | /// <param name="mutableNetworkEdgeEnumerator">The enumerator to query edges.</param> |
| | | 17 | | /// <returns>All sequences starting with the same edges but ending with a different one.</returns> |
| | | 18 | | public static IEnumerable<IEnumerable<(EdgeId edge, bool forward)>> Invert<T>( |
| | | 19 | | this IEnumerable<(EdgeId edge, bool forward)> restrictedSequence, |
| | | 20 | | EdgeEnumerator<T> mutableNetworkEdgeEnumerator) |
| | | 21 | | where T : IEdgeEnumerable |
| | 5 | 22 | | { |
| | 5 | 23 | | var firstPart = new List<(EdgeId edge, bool forward)>(restrictedSequence); |
| | 5 | 24 | | if (firstPart.Count < 2) |
| | 0 | 25 | | { |
| | 0 | 26 | | yield break; // no inverse possible. |
| | | 27 | | } |
| | | 28 | | |
| | | 29 | | // get last. |
| | 5 | 30 | | var last = firstPart[firstPart.Count - 1]; |
| | | 31 | | |
| | | 32 | | // enumerate all edges except the u-turn and the original sequence. |
| | 5 | 33 | | var secondToLast = firstPart[firstPart.Count - 2]; |
| | 5 | 34 | | mutableNetworkEdgeEnumerator.MoveTo(secondToLast.edge, secondToLast.forward); |
| | 5 | 35 | | mutableNetworkEdgeEnumerator.MoveTo(mutableNetworkEdgeEnumerator.Head); |
| | 20 | 36 | | while (mutableNetworkEdgeEnumerator.MoveNext()) |
| | 15 | 37 | | { |
| | 15 | 38 | | var id = mutableNetworkEdgeEnumerator.EdgeId; |
| | 15 | 39 | | if (id == secondToLast.edge && |
| | 15 | 40 | | mutableNetworkEdgeEnumerator.Forward != secondToLast.forward) |
| | 5 | 41 | | { |
| | 5 | 42 | | continue; |
| | | 43 | | } |
| | | 44 | | |
| | 10 | 45 | | if (id == last.edge && |
| | 10 | 46 | | mutableNetworkEdgeEnumerator.Forward == last.forward) |
| | 5 | 47 | | { |
| | 5 | 48 | | continue; |
| | | 49 | | } |
| | | 50 | | |
| | 5 | 51 | | yield return firstPart.Take(firstPart.Count - 1) |
| | 5 | 52 | | .Append((Id: mutableNetworkEdgeEnumerator.EdgeId, mutableNetworkEdgeEnumerator.Forward)); |
| | 5 | 53 | | } |
| | 5 | 54 | | } |
| | | 55 | | } |