Basic order parsing and a unit test

MultiversalDiplomacy/Model/Location.cs

@@ -59,6 +59,12 @@ public class Location
         return (split[0], split[1]);
     }
 
+    /// <summary>
+    /// Whether a name is the name or abbreviation of this location.
+    /// </summary>
+    public bool Is(string name)
+        => name.EqualsAnyCase(Name) || name.EqualsAnyCase(Abbreviation);
+
     public override string ToString()
     {
         return this.Name == "land" || this.Name == "water"

MultiversalDiplomacy/Model/Map.cs

@@ -57,12 +57,8 @@ public class Map
     /// Get a province by name. Throws if the province is not found.
     /// </summary>
     private static Province GetProvince(string provinceName, IEnumerable<Province> provinces)
-        => provinces.SingleOrDefault(
+        => provinces.SingleOrDefault(province => province!.Is(provinceName), null)
-            p => p!.Name.Equals(provinceName, StringComparison.InvariantCultureIgnoreCase)
+        ?? throw new KeyNotFoundException($"Province {provinceName} not found");
-                || p.Abbreviations.Any(
-                    a => a.Equals(provinceName, StringComparison.InvariantCultureIgnoreCase)),
-            null)
-            ?? throw new KeyNotFoundException($"Province {provinceName} not found");
 
     /// <summary>
     /// Get the location in a province matching a predicate. Throws if there is not exactly one

MultiversalDiplomacy/Model/Province.cs

@@ -50,6 +50,12 @@ public class Province
         return this.Name;
     }
 
+    /// <summary>
+    /// Whether a name is the name or abbreviation of this province.
+    /// </summary>
+    public bool Is(string name)
+        => name.EqualsAnyCase(Name) || Abbreviations.Any(name.EqualsAnyCase);
+
     /// <summary>
     /// Create a new province with no supply center.
     /// </summary>

MultiversalDiplomacy/Model/Regex.cs

@@ -174,7 +174,6 @@ public class OrderRegex(World world)
             $"^{world.Map.PowerRegex} {Type} {world.Map.ProvinceRegex}(?:{SlashLocation}|{ParenLocation})?$");
         Match match = reUnit.Match(unitSpec);
         if (!match.Success) {
-            Console.WriteLine($"Could not match unit spec \"{unitSpec}\"");
             return false;
         }
 
@@ -196,28 +195,123 @@ public class OrderRegex(World world)
         return true;
     }
 
-    public static bool TryParseOrder(World world, string power, string command, out Order? order) {
+    public static bool TryParseOrder(World world, string power, string command, [NotNullWhen(true)] out Order? order) {
         order = null;
         OrderRegex re = new(world);
-        Match match;
-        if ((match = re.Hold.Match(command)).Success) {
-            var hold = ParseHold(match);
-            Unit unit = world.Units.First(unit
-                => world.Map.GetLocation(unit.Location).ProvinceName == hold.province
-                && unit.Season.Timeline == (hold.timeline.Length > 0 ? hold.timeline : "a")
-                && unit.Season.Turn.ToString() == (hold.turn.Length > 0 ? hold.turn : "0"));
-            order = new HoldOrder(power, unit);
-            return true;
-        } else if ((match = re.Move.Match(command)).Success) {
-            var move = ParseMove(match);
-            Unit unit = world.Units.First(unit
-                => world.Map.GetLocation(unit.Location).ProvinceName == move.province
-                && unit.Season.Timeline == (move.timeline.Length > 0 ? move.timeline : "a")
-                && unit.Season.Turn.ToString() == (move.turn.Length > 0 ? move.turn : "0"));
-            order = new MoveOrder(power, unit, Season.First, "l");
-            return true;
-        }
 
-        return false;
+        if (re.Hold.Match(command) is Match holdMatch && holdMatch.Success) {
+            return TryParseHoldOrder(world, power, holdMatch, out order);
+        } else if (re.Move.Match(command) is Match moveMatch && moveMatch.Success) {
+            return TryParseMoveOrder(world, power, moveMatch, out order);
+        } else if (re.SupportHold.Match(command) is Match sholdMatch && sholdMatch.Success) {
+            // DATC 4.B.4: coast specification in support orders
+            throw new NotImplementedException();
+        } else if (re.SupportMove.Match(command) is Match smoveMatch && smoveMatch.Success) {
+            throw new NotImplementedException();
+        } else {
+            throw new NotImplementedException();
+        }
     }
-}
+
+    public static bool TryParseHoldOrder(World world, string power, Match match, [NotNullWhen(true)] out Order? order)
+    {
+        order = null;
+        var hold = ParseHold(match);
+        
+        string timeline = hold.timeline.Length > 0
+            ? hold.timeline
+            // If timeline is unspecified, use the root timeline
+            : Season.First.Timeline;
+        var seasonsInTimeline = world.Timelines.Seasons.Where(season => season.Timeline == timeline);
+        if (!seasonsInTimeline.Any()) return false;
+
+        int turn = hold.turn.Length > 0
+            ? int.Parse(hold.turn)
+            // If turn is unspecified, use the latest turn in the timeline
+            : seasonsInTimeline.Max(season => season.Turn);
+
+        Province province = world.Map.Provinces.Single(province => province.Is(hold.province));
+
+        Unit? subject = world.Units.FirstOrDefault(unit
+            => world.Map.GetLocation(unit!.Location).ProvinceName == province.Name
+            && unit!.Season.Timeline == timeline
+            && unit!.Season.Turn == turn,
+            null);
+        if (subject is null) return false;
+
+        order = new HoldOrder(power, subject);
+        return true;
+    }
+
+    public static bool TryParseMoveOrder(World world, string power, Match match, [NotNullWhen(true)] out Order? order)
+    {
+        order = null;
+        var move = ParseMove(match);
+        
+        string timeline = move.timeline.Length > 0
+            ? move.timeline
+            // If timeline is unspecified, use the root timeline
+            : Season.First.Timeline;
+        var seasonsInTimeline = world.Timelines.Seasons.Where(season => season.Timeline == timeline);
+        if (!seasonsInTimeline.Any()) return false;
+
+        int turn = move.turn.Length > 0
+            ? int.Parse(move.turn)
+            // If turn is unspecified, use the latest turn in the timeline
+            : seasonsInTimeline.Max(season => season.Turn);
+
+        Province province = world.Map.Provinces.Single(province => province.Is(move.province));
+
+        // Because only one unit can be in a province at a time, the province is sufficient to identify the subject
+        // and the location is ignored. This also satisfies DATC 4.B.5, which requires that a wrong coast for the
+        // subject be ignored.
+        Unit? subject = world.Units.FirstOrDefault(unit
+            => world.Map.GetLocation(unit!.Location).ProvinceName == province.Name
+            && unit!.Season.Timeline == timeline
+            && unit!.Season.Turn == turn,
+            null);
+        if (subject is null) return false;
+
+        string destTimeline = move.destTimeline.Length > 0
+            ? move.destTimeline
+            // If the destination is unspecified, use the unit's
+            : subject.Season.Timeline;
+
+        int destTurn = move.destTurn.Length > 0
+            ? int.Parse(move.destTurn)
+            // If the destination is unspecified, use the unit's
+            : subject.Season.Turn;
+
+        var destProvince = world.Map.Provinces.Single(province => province.Is(move.destProvince));
+
+        // DATC 4.B.6 requires that "irrelevant" locations like army to Spain nc be ignored.
+        // To satisfy this, any location of the wrong type is categorically ignored, so for an army the
+        // "north coast" location effectively doesn't exist here.
+        var unitLocations = destProvince.Locations.Where(loc => loc.Type switch {
+            LocationType.Land => subject.Type == UnitType.Army,
+            LocationType.Water => subject.Type == UnitType.Fleet,
+            _ => false,
+        });
+        // DATC 4.6.B also requires that unknown coasts be ignored. To satisfy this, an additional filter by name.
+        // Doing both of these filters means "A - Spain/nc" is as meaningful as "F - Spain/wc".
+        var matchingLocations = unitLocations.Where(loc => loc.Is(move.destLocation));
+
+        // If one location matched, use that location. If the coast is inaccessible to the subject, the order will
+        // be invalidated by a path check later to satisfy DATC 4.B.3.
+        string? destLocationKey = matchingLocations.FirstOrDefault(defaultValue: null)?.Key;
+
+        if (destLocationKey is null) {
+            // If no location matched, location was omitted, nonexistent, or the wrong type.
+            // If one location is accessible, DATC 4.B.2 requires that it be used.
+            // If more than one location is accessible, DATC 4.B.1 requires the order fail.
+
+            // TODO check which locations are accessible per the above
+            destLocationKey = unitLocations.First().Key;
+
+            // return false;
+        }
+        
+        order = new MoveOrder(power, subject, new(destTimeline, destTurn), destLocationKey);
+        return true;
+    }
+}

MultiversalDiplomacy/Model/World.cs

@@ -55,7 +55,7 @@ public class World
     public Dictionary<string, OrderHistory> OrderHistory { get; }
 
     /// <summary>
-    /// The shared timeline number generator.
+    /// The state of the multiverse.
     /// </summary>
     public Timelines Timelines { get; }
 

MultiversalDiplomacy/Orders/MoveOrder.cs

@@ -15,7 +15,7 @@ public class MoveOrder : UnitOrder
     public Season Season { get; }
 
     /// <summary>
-    /// The destination location to which the unit should move.
+    /// The destination province/location to which the unit should move.
     /// </summary>
     public string Location { get; }
 

MultiversalDiplomacyTests/RegexTest.cs

@@ -1,6 +1,7 @@
 using NUnit.Framework;
 
 using MultiversalDiplomacy.Model;
+using MultiversalDiplomacy.Orders;
 
 namespace MultiversalDiplomacyTests;
 
@@ -196,4 +197,23 @@ public class RegexTest
         Assert.That(actual, Is.EquivalentTo(expected), "Unexpected parse results");
         Assert.That(actual, Is.EqualTo(expected), "Unexpected parse results");
     }
+
+    [Test]
+    public void OrderParsingTest()
+    {
+        World world = World.WithStandardMap().AddUnits("Germany A Mun");
+        OrderRegex re = new(world);
+
+        var match = re.Move.Match("A Mun - Tyr");
+        var success = OrderRegex.TryParseMoveOrder(world, "Germany", match, out Order? order);
+
+        Assert.That(success, Is.True);
+        Assert.That(order, Is.TypeOf<MoveOrder>());
+        MoveOrder move = (MoveOrder)order!;
+
+        Assert.That(move.Power, Is.EqualTo("Germany"));
+        Assert.That(move.Unit.Key, Is.EqualTo("A a-Munich/l@0"));
+        Assert.That(move.Location, Is.EqualTo("Tyrolia/l"));
+        Assert.That(move.Season.Key, Is.EqualTo("a0"));
+    }
 }