using System.Numerics;
using DatReaderWriter;
using DatReaderWriter.DBObjs;
using DatReaderWriter.Enums;
using DatReaderWriter.Options;
using SysEnv = System.Environment;

string datDir = SysEnv.GetEnvironmentVariable("ACDREAM_DAT_DIR")
    ?? Path.Combine(SysEnv.GetFolderPath(SysEnv.SpecialFolder.UserProfile),
        "Documents", "Asheron's Call");

if (!Directory.Exists(datDir))
{
    Console.Error.WriteLine($"DAT directory not found: {datDir}");
    return 2;
}

using var dats = new DatCollection(datDir, DatAccessType.Read);
if (args.Length > 0 && string.Equals(args[0], "buildings", StringComparison.OrdinalIgnoreCase))
{
    uint landblockId = args.Length > 1 ? ParseHex(args[1]) : 0xA9B40000u;
    int radius = args.Length > 2 ? int.Parse(args[2], System.Globalization.CultureInfo.InvariantCulture) : 0;
    DumpBuildings(dats, landblockId, radius);
}
else if (args.Length > 0 && string.Equals(args[0], "portals", StringComparison.OrdinalIgnoreCase))
{
    var ids = args.Length == 1
        ? new uint[] { 0xA9B40171u }
        : args.Skip(1).Select(ParseHex).ToArray();
    foreach (var envCellId in ids)
        DumpCellPortals(dats, envCellId);
}
else
{
    var ids = args.Length == 0
        ? [0xA9B4013Fu]
        : args.Select(ParseHex).ToArray();

    foreach (var envCellId in ids)
    {
        DumpCell(dats, envCellId);
    }
}

return 0;

static uint ParseHex(string text)
{
    text = text.Trim();
    if (text.StartsWith("0x", StringComparison.OrdinalIgnoreCase))
        return Convert.ToUInt32(text[2..], 16);
    return Convert.ToUInt32(text, 16);
}

static void DumpCell(DatCollection dats, uint envCellId)
{
    Console.WriteLine($"=== EnvCell 0x{envCellId:X8} ===");
    var envCell = dats.Get<EnvCell>(envCellId);
    if (envCell is null)
    {
        Console.WriteLine("missing EnvCell");
        return;
    }

    var envId = 0x0D000000u | envCell.EnvironmentId;
    var environment = dats.Get<DatReaderWriter.DBObjs.Environment>(envId);
    if (environment is null)
    {
        Console.WriteLine($"missing Environment 0x{envId:X8}");
        return;
    }

    if (!environment.Cells.TryGetValue(envCell.CellStructure, out var cellStruct))
    {
        Console.WriteLine($"missing CellStruct {envCell.CellStructure}");
        return;
    }

    Console.WriteLine(
        $"environment=0x{envId:X8} cellStruct={envCell.CellStructure} " +
        $"surfaces={envCell.Surfaces.Count} verts={cellStruct.VertexArray.Vertices.Count} polys={cellStruct.Polygons.Count}");

    int posSides = 0;
    int negSides = 0;
    int skipped = 0;
    int likelyFloor = 0;
    int likelyCeiling = 0;

    foreach (var (polyId, poly) in cellStruct.Polygons.OrderBy(p => p.Key))
    {
        if (poly.VertexIds.Count < 3)
            continue;

        bool emitPos = !poly.Stippling.HasFlag(StipplingType.NoPos) && poly.PosSurface >= 0 && poly.PosSurface < envCell.Surfaces.Count;
        bool emitNeg =
            (poly.Stippling.HasFlag(StipplingType.Negative) ||
             poly.Stippling.HasFlag(StipplingType.Both) ||
             (!poly.Stippling.HasFlag(StipplingType.NoNeg) && poly.SidesType == CullMode.Clockwise))
            && poly.NegSurface >= 0
            && poly.NegSurface < envCell.Surfaces.Count;

        if (emitPos) posSides++;
        if (emitNeg) negSides++;
        if (!emitPos && !emitNeg) skipped++;

        var normal = ComputeNormal(cellStruct, poly);
        var uvRange = UvRange(cellStruct, poly);
        string planeHint = Math.Abs(normal.Z) > 0.9f
            ? normal.Z > 0 ? "floor/up" : "ceiling/down"
            : Math.Abs(normal.Z) > 0.15f ? "slope" : "wall";

        if (normal.Z > 0.9f) likelyFloor++;
        if (normal.Z < -0.9f) likelyCeiling++;

        var posSurf = SurfaceText(envCell, poly.PosSurface);
        var negSurf = SurfaceText(envCell, poly.NegSurface);
        Console.WriteLine(
            $"poly=0x{polyId:X4} pts={poly.VertexIds.Count} n=({normal.X:F3},{normal.Y:F3},{normal.Z:F3}) {planeHint,-12} " +
            $"stip={poly.Stippling} sides={poly.SidesType} pos={poly.PosSurface}->{posSurf} neg={poly.NegSurface}->{negSurf} " +
            $"emitPos={emitPos} emitNeg={emitNeg} posUv={poly.PosUVIndices?.Count ?? 0} negUv={poly.NegUVIndices?.Count ?? 0} " +
            $"uv=({uvRange.Min.X:F3},{uvRange.Min.Y:F3})..({uvRange.Max.X:F3},{uvRange.Max.Y:F3})");
    }

    Console.WriteLine(
        $"summary: posSides={posSides} negSides={negSides} skipped={skipped} " +
        $"likelyFloor={likelyFloor} likelyCeiling={likelyCeiling}");
    Console.WriteLine();
}

static void DumpCellPortals(DatCollection dats, uint envCellId)
{
    Console.WriteLine($"=== EnvCell 0x{envCellId:X8} portals ===");
    var envCell = dats.Get<EnvCell>(envCellId);
    if (envCell is null)
    {
        Console.WriteLine("missing EnvCell");
        return;
    }

    uint lbPrefix = envCellId & 0xFFFF0000u;
    int exitCount = 0;
    int interiorCount = 0;
    for (int i = 0; i < envCell.CellPortals.Count; i++)
    {
        var portal = envCell.CellPortals[i];
        bool isExit = portal.OtherCellId == 0xFFFF;
        if (isExit) exitCount++; else interiorCount++;
        string dest = isExit
            ? "EXIT(outdoor)"
            : $"0x{(lbPrefix | (uint)portal.OtherCellId):X8}";
        Console.WriteLine(
            $"  portal[{i}] other=0x{portal.OtherCellId:X4} -> {dest} " +
            $"flags={portal.Flags} polyId={portal.PolygonId}");
    }

    Console.WriteLine(
        $"summary: cell=0x{envCellId:X8} portals={envCell.CellPortals.Count} " +
        $"exits(0xFFFF)={exitCount} interior={interiorCount} " +
        $"numCellPortals={envCell.CellPortals.Count} seenOutside={(envCell.Flags.HasFlag(EnvCellFlags.SeenOutside) ? "Y" : "n")}");
    Console.WriteLine();
}

static void DumpBuildings(DatCollection dats, uint centerLandblockId, int radius)
{
    int centerX = (int)((centerLandblockId >> 24) & 0xFFu);
    int centerY = (int)((centerLandblockId >> 16) & 0xFFu);
    int totalRegistryBuildings = 0;
    int totalShellEntities = 0;

    for (int dy = -radius; dy <= radius; dy++)
    for (int dx = -radius; dx <= radius; dx++)
    {
        int x = centerX + dx;
        int y = centerY + dy;
        if (x < 0 || x > 255 || y < 0 || y > 255)
            continue;

        uint landblockId = ((uint)x << 24) | ((uint)y << 16);
        var info = dats.Get<LandBlockInfo>(landblockId | 0xFFFEu);
        if (info is null)
            continue;

        var (registryBuildings, shellEntities) = DumpLandblockBuildings(info, landblockId);
        totalRegistryBuildings += registryBuildings;
        totalShellEntities += shellEntities;
    }

    Console.WriteLine(
        $"radius-summary center=0x{(centerLandblockId & 0xFFFF0000u):X8} radius={radius} " +
        $"registryBuildings={totalRegistryBuildings} shellEntities={totalShellEntities}");
}

static (int RegistryBuildings, int ShellEntities) DumpLandblockBuildings(LandBlockInfo info, uint landblockId)
{
    uint lbPrefix = landblockId & 0xFFFF0000u;
    uint stabIdBase = 0xC0000000u
        | (((landblockId >> 24) & 0xFFu) << 16)
        | (((landblockId >> 16) & 0xFFu) << 8);
    uint nextEntityId = stabIdBase + 1u;

    int supportedObjects = 0;
    foreach (var obj in info.Objects)
    {
        if (!IsSupported(obj.Id))
            continue;
        supportedObjects++;
        nextEntityId++;
    }

    Console.WriteLine(
        $"=== Landblock 0x{lbPrefix:X8} info=0x{(lbPrefix | 0xFFFEu):X8} " +
        $"objects={info.Objects.Count} supportedObjects={supportedObjects} buildings={info.Buildings.Count} ===");

    int registryBuildingId = 1;
    int shellEntities = 0;
    foreach (var (building, zeroBased) in info.Buildings.Select((b, i) => (b, i)))
    {
        if (!IsSupported(building.ModelId))
            continue;

        uint shellEntityId = nextEntityId++;
        shellEntities++;

        var portalCells = building.Portals
            .Where(p => p.OtherCellId != 0xFFFF)
            .Select(p => lbPrefix | (uint)p.OtherCellId)
            .Distinct()
            .OrderBy(id => id)
            .ToArray();
        string registryText = portalCells.Length == 0
            ? "none"
            : $"0x{registryBuildingId++:X}";
        string portalText = portalCells.Length == 0
            ? "[]"
            : "[" + string.Join(",", portalCells.Select(id => $"0x{id:X8}")) + "]";

        Console.WriteLine(
            $"buildingOrdinal={zeroBased + 1} registryId={registryText} shellEntity=0x{shellEntityId:X8} " +
            $"model=0x{building.ModelId:X8} pos=({building.Frame.Origin.X:F2},{building.Frame.Origin.Y:F2},{building.Frame.Origin.Z:F2}) " +
            $"portalCells={portalText}");
    }

    Console.WriteLine();
    return (registryBuildingId - 1, shellEntities);
}

static bool IsSupported(uint id)
{
    uint type = id & 0xFF000000u;
    return type == 0x01000000u || type == 0x02000000u;
}

static string SurfaceText(EnvCell envCell, short index)
{
    if (index < 0) return "none";
    if (index >= envCell.Surfaces.Count) return "out-of-range";
    return $"0x{(0x08000000u | envCell.Surfaces[index]):X8}";
}

static Vector3 ComputeNormal(DatReaderWriter.Types.CellStruct cellStruct, DatReaderWriter.Types.Polygon poly)
{
    if (poly.VertexIds.Count < 3) return Vector3.Zero;
    if (!TryGetOrigin(cellStruct, (ushort)poly.VertexIds[0], out var a) ||
        !TryGetOrigin(cellStruct, (ushort)poly.VertexIds[1], out var b) ||
        !TryGetOrigin(cellStruct, (ushort)poly.VertexIds[2], out var c))
    {
        return Vector3.Zero;
    }

    var n = Vector3.Cross(b - a, c - a);
    return n.LengthSquared() > 0f ? Vector3.Normalize(n) : Vector3.Zero;
}

static bool TryGetOrigin(DatReaderWriter.Types.CellStruct cellStruct, ushort id, out Vector3 origin)
{
    if (cellStruct.VertexArray.Vertices.TryGetValue(id, out var vertex))
    {
        origin = vertex.Origin;
        return true;
    }

    origin = Vector3.Zero;
    return false;
}

static (Vector2 Min, Vector2 Max) UvRange(DatReaderWriter.Types.CellStruct cellStruct, DatReaderWriter.Types.Polygon poly)
{
    var min = new Vector2(float.MaxValue, float.MaxValue);
    var max = new Vector2(float.MinValue, float.MinValue);
    bool any = false;
    for (int i = 0; i < poly.VertexIds.Count; i++)
    {
        if (!cellStruct.VertexArray.Vertices.TryGetValue((ushort)poly.VertexIds[i], out var vertex))
            continue;

        ushort uvIdx = 0;
        if (poly.PosUVIndices is not null && i < poly.PosUVIndices.Count)
            uvIdx = poly.PosUVIndices[i];
        if (uvIdx >= vertex.UVs.Count)
            uvIdx = 0;
        if (vertex.UVs.Count == 0)
            continue;

        var uv = new Vector2(vertex.UVs[uvIdx].U, vertex.UVs[uvIdx].V);
        min = Vector2.Min(min, uv);
        max = Vector2.Max(max, uv);
        any = true;
    }

    return any ? (min, max) : (Vector2.Zero, Vector2.Zero);
}