using System.Collections.Generic;
using System.IO;
using Server.Gumps;
using Server.Items;

namespace Server.Commands
{
  public static class Statics
  {
    private const string BaseFreezeWarning = "{0}  " +
                                             "Those items <u>will be removed from the world</u> and placed into the server data files.  " +
                                             "Other players <u>will not see the changes</u> unless you distribute your data files to them.<br><br>" +
                                             "This operation may not complete unless the server and client are using different data files.  " +
                                             "If you receive a message stating 'output data files could not be opened,' then you are probably sharing data files.  " +
                                             "Create a new directory for the world data files (statics*.mul and staidx*.mul) and add that to Scritps/Misc/DataPath.cs.<br><br>" +
                                             "The change will be in effect immediately on the server, however, you must restart your client and update it's data files for the changes to become visible.  " +
                                             "It is strongly recommended that you make backup of the data files mentioned above.  " +
                                             "Do you wish to proceed?";

    private const string BaseUnfreezeWarning = "{0}  " +
                                               "Those items <u>will be removed from the static files</u> and exchanged with unmovable dynamic items.  " +
                                               "Other players <u>will not see the changes</u> unless you distribute your data files to them.<br><br>" +
                                               "This operation may not complete unless the server and client are using different data files.  " +
                                               "If you receive a message stating 'output data files could not be opened,' then you are probably sharing data files.  " +
                                               "Create a new directory for the world data files (statics*.mul and staidx*.mul) and add that to Scritps/Misc/DataPath.cs.<br><br>" +
                                               "The change will be in effect immediately on the server, however, you must restart your client and update it's data files for the changes to become visible.  " +
                                               "It is strongly recommended that you make backup of the data files mentioned above.  " +
                                               "Do you wish to proceed?";

    private static Point3D NullP3D = new Point3D(int.MinValue, int.MinValue, int.MinValue);

    private static byte[] m_Buffer;

    private static StaticTile[] m_TileBuffer = new StaticTile[128];

    public static void Initialize()
    {
      CommandSystem.Register("Freeze", AccessLevel.Administrator, Freeze_OnCommand);
      CommandSystem.Register("FreezeMap", AccessLevel.Administrator, FreezeMap_OnCommand);
      CommandSystem.Register("FreezeWorld", AccessLevel.Administrator, FreezeWorld_OnCommand);

      CommandSystem.Register("Unfreeze", AccessLevel.Administrator, Unfreeze_OnCommand);
      CommandSystem.Register("UnfreezeMap", AccessLevel.Administrator, UnfreezeMap_OnCommand);
      CommandSystem.Register("UnfreezeWorld", AccessLevel.Administrator, UnfreezeWorld_OnCommand);
    }

    public delegate void FreezeCallback( Mobile from, bool okay, StateInfo si );

    [Usage("Freeze")]
    [Description("Makes a targeted area of dynamic items static.")]
    public static void Freeze_OnCommand(CommandEventArgs e)
    {
      Mobile from = e.Mobile;
      BoundingBoxPicker.Begin(from, (map, start, end) => FreezeBox_Callback(from, map, start, end));
    }

    [Usage("FreezeMap")]
    [Description("Makes every dynamic item in your map static.")]
    public static void FreezeMap_OnCommand(CommandEventArgs e)
    {
      Mobile from = e.Mobile;
      Map map = from.Map;

      if (map != null && map != Map.Internal)
        SendWarning(from, "You are about to freeze <u>all items in {0}</u>.", BaseFreezeWarning, map, NullP3D,
          NullP3D, FreezeWarning_Callback);
    }

    [Usage("FreezeWorld")]
    [Description("Makes every dynamic item on all maps static.")]
    public static void FreezeWorld_OnCommand(CommandEventArgs e)
    {
      SendWarning(e.Mobile, "You are about to freeze <u>every item on every map</u>.", BaseFreezeWarning, null,
        NullP3D, NullP3D, FreezeWarning_Callback);
    }

    public static void SendWarning(Mobile m, string header, string baseWarning, Map map, Point3D start, Point3D end,
      FreezeCallback callback)
    {
      m.SendGump(new WarningGump(1060635, 30720, string.Format(baseWarning, string.Format(header, map)), 0xFFC000, 420,
        400, okay => callback(m, okay, new StateInfo(map, start, end))));
    }

    private static void FreezeBox_Callback(Mobile from, Map map, Point3D start, Point3D end)
    {
      SendWarning(from, "You are about to freeze a section of items.", BaseFreezeWarning, map, start, end,
        FreezeWarning_Callback);
    }

    private static void FreezeWarning_Callback(Mobile from, bool okay, StateInfo si)
    {
      if (!okay)
        return;

      Freeze(from, si.m_Map, si.m_Start, si.m_End);
    }

    public static void Freeze(Mobile from, Map targetMap, Point3D start3d, Point3D end3d)
    {
      Dictionary<Map, Dictionary<Point2D, DeltaState>> mapTable = new Dictionary<Map, Dictionary<Point2D, DeltaState>>();

      if (start3d == NullP3D && end3d == NullP3D)
      {
        if (targetMap == null)
          CommandLogging.WriteLine(from, "{0} {1} invoking freeze for every item in every map", from.AccessLevel,
            CommandLogging.Format(from));
        else
          CommandLogging.WriteLine(from, "{0} {1} invoking freeze for every item in {0}", from.AccessLevel,
            CommandLogging.Format(from), targetMap);

        foreach (Item item in World.Items.Values)
        {
          if (targetMap != null && item.Map != targetMap)
            continue;

          if (item.Parent != null)
            continue;

          if (item is Static || item is BaseFloor || item is BaseWall)
          {
            Map itemMap = item.Map;

            if (itemMap == null || itemMap == Map.Internal)
              continue;

            if (!mapTable.TryGetValue(itemMap, out Dictionary<Point2D, DeltaState> table))
              mapTable[itemMap] = table = new Dictionary<Point2D, DeltaState>();

            Point2D p = new Point2D(item.X >> 3, item.Y >> 3);

            if (!table.TryGetValue(p, out DeltaState state))
              table[p] = state = new DeltaState(p);

            state.m_List.Add(item);
          }
        }
      }
      else if (targetMap != null)
      {
        Point2D start = targetMap.Bound(new Point2D(start3d)), end = targetMap.Bound(new Point2D(end3d));

        CommandLogging.WriteLine(from, "{0} {1} invoking freeze from {2} to {3} in {4}", from.AccessLevel,
          CommandLogging.Format(from), start, end, targetMap);

        IPooledEnumerable<Item> eable =
          targetMap.GetItemsInBounds(new Rectangle2D(start.X, start.Y, end.X - start.X + 1, end.Y - start.Y + 1));

        foreach (Item item in eable)
          if (item is Static || item is BaseFloor || item is BaseWall)
          {
            Map itemMap = item.Map;

            if (itemMap == null || itemMap == Map.Internal)
              continue;

            if (!mapTable.TryGetValue(itemMap, out Dictionary<Point2D, DeltaState> table))
              mapTable[itemMap] = table = new Dictionary<Point2D, DeltaState>();

            Point2D p = new Point2D(item.X >> 3, item.Y >> 3);

            if (!table.TryGetValue(p, out DeltaState state))
              table[p] = state = new DeltaState(p);

            state.m_List.Add(item);
          }

        eable.Free();
      }

      if (mapTable.Count == 0)
      {
        from.SendGump(new NoticeGump(1060637, 30720,
          "No freezable items were found.  Only the following item types are frozen:<br> - Static<br> - BaseFloor<br> - BaseWall",
          0xFFC000, 320, 240));
        return;
      }

      bool badDataFile = false;

      int totalFrozen = 0;

      foreach (var (map, table) in mapTable)
      {
        TileMatrix matrix = map.Tiles;

        using FileStream idxStream = OpenWrite(matrix.IndexStream);
        using FileStream mulStream = OpenWrite(matrix.DataStream);
        if (idxStream == null || mulStream == null)
        {
          badDataFile = true;
          continue;
        }

        BinaryReader idxReader = new BinaryReader(idxStream);

        BinaryWriter idxWriter = new BinaryWriter(idxStream);
        BinaryWriter mulWriter = new BinaryWriter(mulStream);

        foreach (DeltaState state in table.Values)
        {
          StaticTile[] oldTiles = ReadStaticBlock(idxReader, mulStream, state.m_X, state.m_Y,
            matrix.BlockWidth, matrix.BlockHeight, out int oldTileCount);

          if (oldTileCount < 0)
            continue;

          int newTileCount = 0;
          StaticTile[] newTiles = new StaticTile[state.m_List.Count];

          for (int i = 0; i < state.m_List.Count; ++i)
          {
            Item item = state.m_List[i];

            int xOffset = item.X - state.m_X * 8;
            int yOffset = item.Y - state.m_Y * 8;

            if (xOffset < 0 || xOffset >= 8 || yOffset < 0 || yOffset >= 8)
              continue;

            StaticTile newTile = new StaticTile((ushort)item.ItemID, (byte)xOffset, (byte)yOffset,
              (sbyte)item.Z, (short)item.Hue);

            newTiles[newTileCount++] = newTile;

            item.Delete();

            ++totalFrozen;
          }

          int mulPos = -1;
          int length = -1;
          int extra = 0;

          if (oldTileCount + newTileCount > 0)
          {
            mulWriter.Seek(0, SeekOrigin.End);

            mulPos = (int)mulWriter.BaseStream.Position;
            length = (oldTileCount + newTileCount) * 7;
            extra = 1;

            for (int i = 0; i < oldTileCount; ++i)
            {
              StaticTile toWrite = oldTiles[i];

              mulWriter.Write((ushort)toWrite.ID);
              mulWriter.Write((byte)toWrite.X);
              mulWriter.Write((byte)toWrite.Y);
              mulWriter.Write((sbyte)toWrite.Z);
              mulWriter.Write((short)toWrite.Hue);
            }

            for (int i = 0; i < newTileCount; ++i)
            {
              StaticTile toWrite = newTiles[i];

              mulWriter.Write((ushort)toWrite.ID);
              mulWriter.Write((byte)toWrite.X);
              mulWriter.Write((byte)toWrite.Y);
              mulWriter.Write((sbyte)toWrite.Z);
              mulWriter.Write((short)toWrite.Hue);
            }

            mulWriter.Flush();
          }

          int idxPos = (state.m_X * matrix.BlockHeight + state.m_Y) * 12;

          idxWriter.Seek(idxPos, SeekOrigin.Begin);
          idxWriter.Write(mulPos);
          idxWriter.Write(length);
          idxWriter.Write(extra);

          idxWriter.Flush();

          matrix.SetStaticBlock(state.m_X, state.m_Y, null);
        }
      }

      if (totalFrozen == 0 && badDataFile)
        from.SendGump(new NoticeGump(1060637, 30720,
          "Output data files could not be opened and the freeze operation has been aborted.<br><br>This probably means your server and client are using the same data files.  Instructions on how to resolve this can be found in the first warning window.",
          0xFFC000, 320, 240));
      else
        from.SendGump(new NoticeGump(1060637, 30720,
          $"Freeze operation completed successfully.<br><br>{totalFrozen} item{(totalFrozen != 1 ? "s were" : " was")} frozen.<br><br>You must restart your client and update it's data files to see the changes.",
          0xFFC000, 320, 240));
    }

    [Usage("Unfreeze")]
    [Description("Makes a targeted area of static items dynamic.")]
    public static void Unfreeze_OnCommand(CommandEventArgs e)
    {
      Mobile from = e.Mobile;
      BoundingBoxPicker.Begin(from, (map, start, end) => UnfreezeBox_Callback(from, map, start, end));
    }

    [Usage("UnfreezeMap")]
    [Description("Makes every static item in your map dynamic.")]
    public static void UnfreezeMap_OnCommand(CommandEventArgs e)
    {
      Map map = e.Mobile.Map;

      if (map != null && map != Map.Internal)
        SendWarning(e.Mobile, "You are about to unfreeze <u>all items in {0}</u>.", BaseUnfreezeWarning, map,
          NullP3D, NullP3D, UnfreezeWarning_Callback);
    }

    [Usage("UnfreezeWorld")]
    [Description("Makes every static item on all maps dynamic.")]
    public static void UnfreezeWorld_OnCommand(CommandEventArgs e)
    {
      SendWarning(e.Mobile, "You are about to unfreeze <u>every item on every map</u>.", BaseUnfreezeWarning, null,
        NullP3D, NullP3D, UnfreezeWarning_Callback);
    }

    private static void UnfreezeBox_Callback(Mobile from, Map map, Point3D start, Point3D end)
    {
      SendWarning(from, "You are about to unfreeze a section of items.", BaseUnfreezeWarning, map, start, end,
        UnfreezeWarning_Callback);
    }

    private static void UnfreezeWarning_Callback(Mobile from, bool okay, StateInfo si)
    {
      if (!okay)
        return;

      Unfreeze(from, si.m_Map, si.m_Start, si.m_End);
    }

    private static void DoUnfreeze(Map map, Point2D start, Point2D end, ref bool badDataFile, ref int totalUnfrozen)
    {
      start = map.Bound(start);
      end = map.Bound(end);

      int xStartBlock = start.X >> 3;
      int yStartBlock = start.Y >> 3;
      int xEndBlock = end.X >> 3;
      int yEndBlock = end.Y >> 3;

      int xTileStart = start.X, yTileStart = start.Y;
      int xTileWidth = end.X - start.X + 1, yTileHeight = end.Y - start.Y + 1;

      TileMatrix matrix = map.Tiles;

      using FileStream idxStream = OpenWrite(matrix.IndexStream);
      using FileStream mulStream = OpenWrite(matrix.DataStream);
      if (idxStream == null || mulStream == null)
      {
        badDataFile = true;
        return;
      }

      BinaryReader idxReader = new BinaryReader(idxStream);

      BinaryWriter idxWriter = new BinaryWriter(idxStream);
      BinaryWriter mulWriter = new BinaryWriter(mulStream);

      for (int x = xStartBlock; x <= xEndBlock; ++x)
      for (int y = yStartBlock; y <= yEndBlock; ++y)
      {
        StaticTile[] oldTiles = ReadStaticBlock(idxReader, mulStream, x, y, matrix.BlockWidth,
          matrix.BlockHeight, out int oldTileCount);

        if (oldTileCount < 0)
          continue;

        int newTileCount = 0;
        StaticTile[] newTiles = new StaticTile[oldTileCount];

        int baseX = (x << 3) - xTileStart, baseY = (y << 3) - yTileStart;

        for (int i = 0; i < oldTileCount; ++i)
        {
          StaticTile oldTile = oldTiles[i];

          int px = baseX + oldTile.X;
          int py = baseY + oldTile.Y;

          if (px < 0 || px >= xTileWidth || py < 0 || py >= yTileHeight)
          {
            newTiles[newTileCount++] = oldTile;
          }
          else
          {
            ++totalUnfrozen;

            Item item = new Static(oldTile.ID);

            item.Hue = oldTile.Hue;

            item.MoveToWorld(new Point3D(px + xTileStart, py + yTileStart, oldTile.Z), map);
          }
        }

        int mulPos = -1;
        int length = -1;
        int extra = 0;

        if (newTileCount > 0)
        {
          mulWriter.Seek(0, SeekOrigin.End);

          mulPos = (int)mulWriter.BaseStream.Position;
          length = newTileCount * 7;
          extra = 1;

          for (int i = 0; i < newTileCount; ++i)
          {
            StaticTile toWrite = newTiles[i];

            mulWriter.Write((ushort)toWrite.ID);
            mulWriter.Write((byte)toWrite.X);
            mulWriter.Write((byte)toWrite.Y);
            mulWriter.Write((sbyte)toWrite.Z);
            mulWriter.Write((short)toWrite.Hue);
          }

          mulWriter.Flush();
        }

        int idxPos = (x * matrix.BlockHeight + y) * 12;

        idxWriter.Seek(idxPos, SeekOrigin.Begin);
        idxWriter.Write(mulPos);
        idxWriter.Write(length);
        idxWriter.Write(extra);

        idxWriter.Flush();

        matrix.SetStaticBlock(x, y, null);
      }
    }

    public static void DoUnfreeze(Map map, ref bool badDataFile, ref int totalUnfrozen)
    {
      DoUnfreeze(map, Point2D.Zero, new Point2D(map.Width - 1, map.Height - 1), ref badDataFile, ref totalUnfrozen);
    }

    public static void Unfreeze(Mobile from, Map map, Point3D start, Point3D end)
    {
      int totalUnfrozen = 0;
      bool badDataFile = false;

      if (map == null)
      {
        CommandLogging.WriteLine(from, "{0} {1} invoking unfreeze for every item in every map", from.AccessLevel,
          CommandLogging.Format(from));

        DoUnfreeze(Map.Felucca, ref badDataFile, ref totalUnfrozen);
        DoUnfreeze(Map.Trammel, ref badDataFile, ref totalUnfrozen);
        DoUnfreeze(Map.Ilshenar, ref badDataFile, ref totalUnfrozen);
        DoUnfreeze(Map.Malas, ref badDataFile, ref totalUnfrozen);
        DoUnfreeze(Map.Tokuno, ref badDataFile, ref totalUnfrozen);
      }
      else if (start == NullP3D && end == NullP3D)
      {
        CommandLogging.WriteLine(from, "{0} {1} invoking unfreeze for every item in {2}", from.AccessLevel,
          CommandLogging.Format(from), map);

        DoUnfreeze(map, ref badDataFile, ref totalUnfrozen);
      }
      else
      {
        CommandLogging.WriteLine(from, "{0} {1} invoking unfreeze from {2} to {3} in {4}", from.AccessLevel,
          CommandLogging.Format(from), new Point2D(start), new Point2D(end), map);

        DoUnfreeze(map, new Point2D(start), new Point2D(end), ref badDataFile, ref totalUnfrozen);
      }

      if (totalUnfrozen == 0 && badDataFile)
        from.SendGump(new NoticeGump(1060637, 30720,
          "Output data files could not be opened and the unfreeze operation has been aborted.<br><br>This probably means your server and client are using the same data files.  Instructions on how to resolve this can be found in the first warning window.",
          0xFFC000, 320, 240));
      else
        from.SendGump(new NoticeGump(1060637, 30720,
          $"Unfreeze operation completed successfully.<br><br>{totalUnfrozen} item{(totalUnfrozen != 1 ? "s were" : " was")} unfrozen.<br><br>You must restart your client and update it's data files to see the changes.",
          0xFFC000, 320, 240));
    }

    private static FileStream OpenWrite(FileStream orig)
    {
      if (orig == null)
        return null;

      try
      {
        return new FileStream(orig.Name, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
      }
      catch
      {
        return null;
      }
    }

    private static StaticTile[] ReadStaticBlock(BinaryReader idxReader, FileStream mulStream, int x, int y, int width,
      int height, out int count)
    {
      try
      {
        if (x < 0 || x >= width || y < 0 || y >= height)
        {
          count = -1;
          return m_TileBuffer;
        }

        idxReader.BaseStream.Seek((x * height + y) * 12, SeekOrigin.Begin);

        int lookup = idxReader.ReadInt32();
        int length = idxReader.ReadInt32();

        if (lookup < 0 || length <= 0)
        {
          count = 0;
        }
        else
        {
          count = length / 7;

          mulStream.Seek(lookup, SeekOrigin.Begin);

          if (m_TileBuffer.Length < count)
            m_TileBuffer = new StaticTile[count];

          StaticTile[] staTiles = m_TileBuffer;

          if (m_Buffer == null || length > m_Buffer.Length)
            m_Buffer = new byte[length];

          mulStream.Read(m_Buffer, 0, length);

          int index = 0;

          for (int i = 0; i < count; ++i)
            staTiles[i].Set((ushort)(m_Buffer[index++] | m_Buffer[index++] << 8),
              m_Buffer[index++], m_Buffer[index++], (sbyte)m_Buffer[index++],
              (short)(m_Buffer[index++] | m_Buffer[index++] << 8));
        }
      }
      catch
      {
        count = -1;
      }

      return m_TileBuffer;
    }

    private class DeltaState
    {
      public List<Item> m_List;
      public int m_X, m_Y;

      public DeltaState(Point2D p)
      {
        m_X = p.X;
        m_Y = p.Y;
        m_List = new List<Item>();
      }
    }

    public class StateInfo
    {
      public Map m_Map;
      public Point3D m_Start, m_End;

      public StateInfo(Map map, Point3D start, Point3D end)
      {
        m_Map = map;
        m_Start = start;
        m_End = end;
      }
    }
  }
}