MACVENTURE: Add generic container

1 files changed, 203 insertions, 0 deletions

diff --git a/engines/macventure/container.h b/engines/macventure/container.h
new file mode 100644
index 0000000000..fc350735d2
--- /dev/null
+++ b/engines/macventure/container.h
@@ -0,0 +1,203 @@
+/* ScummVM - Graphic Adventure Engine
+*
+* ScummVM is the legal property of its developers, whose names
+* are too numerous to list here. Please refer to the COPYRIGHT
+* file distributed with this source distribution.
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License
+* as published by the Free Software Foundation; either version 2
+* of the License, or (at your option) any later version.
+
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU General Public License for more details.
+
+* You should have received a copy of the GNU General Public License
+* along with this program; if not, write to the Free Software
+* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*
+*/
+
+#ifndef MACVENTURE_CONTAINER_H
+#define MACVENTURE_CONTAINER_H
+
+#include "macventure/macventure.h"
+
+#include "common/file.h"
+
+namespace MacVenture {
+
+
+struct ItemGroup {
+	uint32 bitOffset; //It's really uint24
+	uint32 offset; //It's really uint24
+	uint32 lengths[64];
+};
+
+typedef uint32 ContainerHeader;
+
+template <class T>
+class Container {	
+
+public:
+	Container(char *filename) {
+		if (!_file.open(filename))
+			error("Could not open %s", filename);
+
+		_res = _file.readStream(_file.size());
+		_header = _res->readUint32BE();
+		
+		if (!(_header & 0x80000000)) { 
+			// Is simplified container
+			int dataLen = _res->size() - sizeof(_header);
+			_lenObjs = _header;
+			_numObjs = dataLen / _lenObjs;
+		}
+		else {
+			ContainerHeader subHead = _header & 0x7fffffff;
+			_res->seek(subHead, SEEK_SET);
+			_numObjs = _res->readUint16BE();
+
+			for (int i = 0; i < 15; ++i)
+				_huff[i] = _res->readUint16BE();
+
+			for (int i = 0; i < 16; ++i)
+				_lens[i] = _res->readByte();
+
+			ItemGroup group;
+			for (int i = 0; i < _numObjs; ++i) {	
+				uint32 bits;
+				if ((i & 0x37) == 0) { // It's the start of a group					
+					// Place myself in the correct position to read group
+					_res->seek(subHead + (i >> 6) * 6 + 0x30, SEEK_SET);
+					_res->read(&bits, 3);
+					bits >>= 4;
+					_res->read(&group.offset, 3); // Read 3 bytes
+					group.offset >>= 4;
+					bits &= 7;
+					group.bitOffset = bits;
+					_res->seek(subHead + (bits >> 3), SEEK_SET);
+				}	
+
+				// Workaround to implement peek
+				// Read the value in 32 bits
+				uint32 v = (_res->readUint32BE() >> (16 - bits)) & 0xffff;
+				// Go back
+				_res->seek(-4, SEEK_CUR); 
+
+				// Look in the Huffman table
+				int x;
+				for (x = 0; x<16; x++)
+					if (_huff[x] > v) break;
+
+				// Bits that we need to read from the length table
+				uint8 bitsToRead = _lens[x];
+
+				bits += (bitsToRead & 0xf);
+				if (bits & 0x10) {
+					bits &= 0xf;
+					_res->seek(2, SEEK_CUR);
+				}
+
+				// We already have in bits the first 4 bits (97)
+				bitsToRead = bitsToRead >> 4;
+
+				// The actual length of the object
+				uint32 len = 0;
+				if (bitsToRead) {
+					// Peek 4 bytes
+					len = _res->readUint32BE();
+					_res->seek(-4, SEEK_CUR);
+
+					bitsToRead--;
+
+					if (bitsToRead == 0) len = 0;
+					else len >>= (32 - bitsToRead) - bits;
+
+					len &= (1 << bitsToRead) - 1;
+					len |= 1 << bitsToRead;
+
+					if (bits & 0x10) {
+						bits &= 0xf;
+						_res->seek(2, SEEK_CUR);
+					}
+
+				}
+
+				group.lengths[(i & 0x3f)] = len;
+
+				if ((i & 0x37) == 0) {
+					_groups.push_back(group);
+				}
+			}			 
+		}
+	}
+
+	~Container() {
+
+		if (_file.isOpen())
+			_file.close();
+
+		if (_res)
+			delete _res;
+	}
+
+public:
+	T getItem(uint32 id) {
+		T item;
+		if (!(_header & 0x80000000)) {
+			_res->seek((id * _lenObjs) + sizeof(_header), SEEK_SET);
+			_res->read(&item, _lenObjs);
+		} else {
+			ContainerHeader subHead = _header & 0x7fffffff;
+			uint32 groupID = (id >> 6);
+			uint32 objectIndex = id & 0x3f; // Index within the group
+
+			_res->seek(subHead + (groupID * 6), SEEK_SET);
+
+			uint32 offset = 0;
+			for (int i = 0; i < objectIndex; i++) {
+				offset += _groups[groupID].lengths[i];
+			}
+
+			_res->seek(offset, SEEK_CUR);
+
+			_res->read(&item, _groups[groupID].lengths[objectIndex]);
+		}
+		return item;
+	}
+
+protected:
+	
+	uint _lenObjs;
+	uint _numObjs;
+
+	ContainerHeader _header;
+	
+	uint16 _huff[15];   // huffman masks
+	uint8  _lens[16];   // huffman lengths
+	Common::Array<ItemGroup> _groups;
+
+	Common::File _file;
+	Common::SeekableReadStream *_res;
+
+};
+
+/*
+template <typedef T>
+class PersistentContainer : public Container {
+public:
+	PersistentContainer(Common::String filename) :
+		Container(filename) {
+		// Load 
+	}
+
+private:
+
+};*/
+
+} // End of namespace MacVenture
+
+#endif