using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

namespace Substrate
{
    using NBT;

    public class ChunkRef : IChunk
    {
        private IChunkContainer _container;
        private IChunkCache _cache;
        private Chunk _chunk;

        private int _cx;
        private int _cz;

        private bool _dirty;

        public int X
        {
            get { return _container.ChunkGlobalX(_cx); }
        }

        public int Z
        {
            get { return _container.ChunkGlobalZ(_cz); }
        }

        

        public int LocalX
        {
            get { return _container.ChunkLocalX(_cx); }
        }

        public int LocalZ
        {
            get { return _container.ChunkLocalZ(_cz); }
        }

        public ChunkRef (IChunkContainer container, IChunkCache cache, int cx, int cz)
        {
            _container = container;
            _cache = cache;
            _cx = cx;
            _cz = cz;

            if (!_container.ChunkExists(cx, cz)) {
                throw new MissingChunkException();
            }
        }

        public int BlockGlobalX (int x)
        {
            return _container.ChunkGlobalX(_cx) * XDim + x;
        }

        public int BlockGlobalY (int y)
        {
            return y;
        }

        public int BlockGlobalZ (int z)
        {
            return _container.ChunkGlobalZ(_cz) * ZDim + z;
        }

        public int BlockLocalX (int x)
        {
            return x;
        }

        public int BlockLocalY (int y)
        {
            return y;
        }

        public int BlockLocalZ (int z)
        {
            return z;
        }

        private Chunk GetChunk ()
        {
            if (_chunk == null) {
                _chunk = _container.GetChunk(_cx, _cz);
            }
            return _chunk;
        }

        private bool MarkDirty ()
        {
            if (_dirty) {
                return false;
            }

            _dirty = true;
            _cache.MarkChunkDirty(this);
            return true;
        }

        public ChunkRef GetNorthNeighbor ()
        {
            return _container.GetChunkRef(_cx - 1, _cz);
        }

        public ChunkRef GetSouthNeighbor ()
        {
            return _container.GetChunkRef(_cx + 1, _cz);
        }

        public ChunkRef GetEastNeighbor ()
        {
            return _container.GetChunkRef(_cx, _cz - 1);
        }

        public ChunkRef GetWestNeighbor ()
        {
            return _container.GetChunkRef(_cx, _cz + 1);
        }

        public Chunk GetChunkCopy ()
        {
            return GetChunk().Copy();
        }

        public Chunk GetChunkRef ()
        {
            Chunk chunk = GetChunk();
            _chunk = null;

            return chunk;
        }

        public void SetChunkRef (Chunk chunk)
        {
            _chunk = chunk;
            _chunk.SetLocation(_cx, _cz);
            MarkDirty();
        }

        #region IChunk Members

        public bool IsTerrainPopulated
        {
	        get { return GetChunk().IsTerrainPopulated; }
	        set 
            {
                if (GetChunk().IsTerrainPopulated != value) {
                    GetChunk().IsTerrainPopulated = value; 
                    MarkDirty();
                }
            }
        }

        public bool Save (Stream outStream)
        {
            if (_dirty) {
                if (GetChunk().Save(outStream)) {
                    _dirty = false;
                    return true;
                }
                return false;
            }
            return true;
        }

        public Block GetBlock (int lx, int ly, int lz)
        {
 	        return new Block(this, lx, ly, lz);
        }

        public BlockRef GetBlockRef (int lx, int ly, int lz)
        {
 	        return new BlockRef(this, lx, ly, lz);
        }

        public BlockInfo GetBlockInfo (int lx, int ly, int lz)
        {
 	        return GetChunk().GetBlockInfo(lx, ly, lz);
        }

        public void SetBlock (int lx, int ly, int lz, Block block)
        {
            GetChunk().SetBlock(lx, ly, lz, block);
        }

        public int CountBlockID (int id)
        {
 	        return GetChunk().CountBlockID(id);
        }

        public int CountBlockData (int id, int data)
        {
 	        return GetChunk().CountBlockData(id, data);
        }

        public int CountEntities ()
        {
            return GetChunk().CountEntities();
        }

        public int GetHeight (int lx, int lz)
        {
 	        return GetChunk().GetHeight(lx, lz);
        }

        #endregion


        #region IBoundedBlockContainer Members

        public int XDim
        {
            get { return _chunk.XDim; }
        }

        public int YDim
        {
            get { return _chunk.YDim; }
        }

        public int ZDim
        {
            get { return _chunk.ZDim; }
        }

        #endregion


        #region IBlockContainer Members

        IBlock IBlockContainer.GetBlock (int lx, int ly, int lz)
        {
            return new Block(this, lx, ly, lz);
        }

        IBlock IBlockContainer.GetBlockRef (int lx, int ly, int lz)
        {
            return new BlockRef(this, lx, ly, lz);
        }

        public void SetBlock (int lx, int ly, int lz, IBlock block)
        {
            GetChunk().SetBlock(lx, ly, lz, block);
        }

        public int GetBlockID (int lx, int ly, int lz)
        {
            return GetChunk().GetBlockID(lx, ly, lz);
        }

        public int GetBlockData (int lx, int ly, int lz)
        {
            return GetChunk().GetBlockData(lx, ly, lz);
        }

        public bool SetBlockID (int lx, int ly, int lz, int id)
        {
            if (GetChunk().SetBlockID(lx, ly, lz, id)) {
                MarkDirty();
                return true;
            }
            return false;
        }

        public bool SetBlockData (int lx, int ly, int lz, int data)
        {
            if (GetChunk().SetBlockData(lx, ly, lz, data)) {
                MarkDirty();
                return true;
            }
            return false;
        }

        #endregion


        #region ILitBlockContainer Members

        ILitBlock ILitBlockContainer.GetBlock (int lx, int ly, int lz)
        {
            throw new NotImplementedException();
        }

        ILitBlock ILitBlockContainer.GetBlockRef (int lx, int ly, int lz)
        {
            return new BlockRef(this, lx, ly, lz);
        }

        public void SetBlock (int lx, int ly, int lz, ILitBlock block)
        {
            GetChunk().SetBlock(lx, ly, lz, block);
        }

        public int GetBlockLight (int lx, int ly, int lz)
        {
            return GetChunk().GetBlockSkyLight(lx, ly, lz);
        }

        public int GetBlockSkyLight (int lx, int ly, int lz)
        {
            return GetChunk().GetBlockSkyLight(lx, ly, lz);
        }

        public bool SetBlockLight (int lx, int ly, int lz, int light)
        {
            if (GetChunk().SetBlockLight(lx, ly, lz, light)) {
                MarkDirty();
                return true;
            }
            return false;
        }

        public bool SetBlockSkyLight (int lx, int ly, int lz, int light)
        {
            if (GetChunk().SetBlockSkyLight(lx, ly, lz, light)) {
                MarkDirty();
                return true;
            }
            return false;
        }

        #endregion


        #region IPropertyBlockContainer Members

        IPropertyBlock IPropertyBlockContainer.GetBlock (int lx, int ly, int lz)
        {
            return new Block(this, lx, ly, lz);
        }

        IPropertyBlock IPropertyBlockContainer.GetBlockRef (int lx, int ly, int lz)
        {
            return new BlockRef(this, lx, ly, lz);
        }

        public void SetBlock (int lx, int ly, int lz, IPropertyBlock block)
        {
            GetChunk().SetBlock(lx, ly, lz, block);
        }

        public TileEntity GetTileEntity (int lx, int ly, int lz)
        {
            return GetChunk().GetTileEntity(lx, ly, lz);
        }

        public bool SetTileEntity (int lx, int ly, int lz, TileEntity te)
        {
            if (GetChunk().SetTileEntity(lx, ly, lz, te)) {
                MarkDirty();
                return true;
            }
            return false;
        }

        public bool ClearTileEntity (int lx, int ly, int lz)
        {
            if (GetChunk().ClearTileEntity(lx, ly, lz)) {
                MarkDirty();
                return true;
            }
            return false;
        }

        #endregion


        #region IEntityContainer Members

        public List<Entity> FindEntities (string id)
        {
            return GetChunk().FindEntities(id);
        }

        public List<Entity> FindEntities (Predicate<Entity> match)
        {
            return GetChunk().FindEntities(match);
        }

        public bool AddEntity (Entity ent)
        {
            if (GetChunk().AddEntity(ent)) {
                MarkDirty();
                return true;
            }
            return false;
        }

        public int RemoveEntities (string id)
        {
            int ret = GetChunk().RemoveEntities(id);
            if (ret > 0) {
                MarkDirty();
            }
            return ret;
        }

        public int RemoveEntities (Predicate<Entity> match)
        {
            int ret = GetChunk().RemoveEntities(match);
            if (ret > 0) {
                MarkDirty();
            }
            return ret;
        }

        #endregion
    }

}