Chessistics/chessistics-tests/Model/TerrainPatchTests.cs

using Chessistics.Engine.Model;
using Xunit;

namespace Chessistics.Tests.Model;

public class TerrainPatchTests
{
    [Fact]
    public void TerrainPatch_DemandOverwritesProduction_ClearsProduction()
    {
        // Setup: board with a production at (2,0)
        var state = BoardState.FromCampaign(new CampaignDef
        {
            Name = "Test", InitialWidth = 4, InitialHeight = 1,
            Missions = [new MissionDef
            {
                Id = 1, Name = "M1",
                TerrainPatch = new TerrainPatch
                {
                    NewWidth = 4, NewHeight = 1,
                    Cells = [new PatchCell { Col = 2, Row = 0, Type = CellType.Production,
                        Production = new ProductionDef(new Coords(2, 0), "Prod", CargoType.Wood, 4) }]
                },
                Stock = []
            }]
        });

        // Apply mission 0 terrain
        state.ApplyTerrainPatch(state.Campaign!.CurrentMission.TerrainPatch, 0);
        Assert.True(state.Productions.ContainsKey(new Coords(2, 0)));

        // Now overwrite with a demand at same position
        var patch = new TerrainPatch
        {
            NewWidth = 4, NewHeight = 1,
            Cells = [new PatchCell { Col = 2, Row = 0, Type = CellType.Demand,
                Demand = new DemandDef(new Coords(2, 0), "Demand", CargoType.Wood, 2) }]
        };
        state.ApplyTerrainPatch(patch, 1);

        // Production should be gone, demand should exist
        Assert.False(state.Productions.ContainsKey(new Coords(2, 0)));
        Assert.True(state.Demands.ContainsKey(new Coords(2, 0)));
        Assert.Equal(CellType.Demand, state.GetCell(new Coords(2, 0)));
    }

    [Fact]
    public void TerrainPatch_WallRemovesPiecesOnCell()
    {
        var state = BoardState.FromCampaign(new CampaignDef
        {
            Name = "Test", InitialWidth = 4, InitialHeight = 2,
            Missions = [new MissionDef
            {
                Id = 1, Name = "M1",
                TerrainPatch = new TerrainPatch { NewWidth = 4, NewHeight = 2, Cells = [] },
                Stock = [new PieceStock(PieceKind.Rook, 2)]
            }]
        });
        state.ApplyTerrainPatch(state.Campaign!.CurrentMission.TerrainPatch, 0);
        state.AddStock(state.Campaign.CurrentMission.Stock);

        // Place a piece with start=(2,0), end=(3,0)
        state.Pieces.Add(new PieceState(1, PieceKind.Rook, new Coords(2, 0), new Coords(3, 0), 1));
        state.RemainingStock[PieceKind.Rook] = 1;

        // Apply wall on (2,0) — should remove the piece
        var patch = new TerrainPatch
        {
            NewWidth = 4, NewHeight = 2,
            Cells = [new PatchCell { Col = 2, Row = 0, Type = CellType.Wall }]
        };
        state.ApplyTerrainPatch(patch, 1);

        Assert.Empty(state.Pieces);
        Assert.Equal(2, state.RemainingStock[PieceKind.Rook]); // returned to stock
    }

    [Fact]
    public void TerrainPatch_ProductionOverwritesDemand_ClearsDemand()
    {
        var state = BoardState.FromCampaign(new CampaignDef
        {
            Name = "Test", InitialWidth = 4, InitialHeight = 1,
            Missions = [new MissionDef
            {
                Id = 1, Name = "M1",
                TerrainPatch = new TerrainPatch
                {
                    NewWidth = 4, NewHeight = 1,
                    Cells = [new PatchCell { Col = 1, Row = 0, Type = CellType.Demand,
                        Demand = new DemandDef(new Coords(1, 0), "D", CargoType.Wood, 2) }]
                },
                Stock = []
            }]
        });
        state.ApplyTerrainPatch(state.Campaign!.CurrentMission.TerrainPatch, 0);
        Assert.True(state.Demands.ContainsKey(new Coords(1, 0)));

        // Overwrite with production
        var patch = new TerrainPatch
        {
            NewWidth = 4, NewHeight = 1,
            Cells = [new PatchCell { Col = 1, Row = 0, Type = CellType.Production,
                Production = new ProductionDef(new Coords(1, 0), "P", CargoType.Stone, 4) }]
        };
        state.ApplyTerrainPatch(patch, 1);

        Assert.False(state.Demands.ContainsKey(new Coords(1, 0)));
        Assert.True(state.Productions.ContainsKey(new Coords(1, 0)));
    }
}