MatFileHandler/MatFileHandler/SubsystemDataReader.cs

413 lines
17 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
namespace MatFileHandler
{
/// <summary>
/// Reader for "subsystem data" in .mat files.
/// </summary>
internal class SubsystemDataReader
{
/// <summary>
/// Read subsystem data from a given byte array.
/// </summary>
/// <param name="bytes">Byte array with the data.</param>
/// <param name="subsystemData">
/// Link to the existing subsystem data; this will be put in nested OpaqueLink objects
/// and later replaced with the subsystem data that we are currently reading.</param>
/// <returns>Subsystem data read.</returns>
public static SubsystemData Read(byte[] bytes, SubsystemData subsystemData)
{
var rawVariables = ReadRawVariables(bytes, subsystemData);
// Parse subsystem data.
var mainVariable = rawVariables[0].DataElement as IStructureArray
?? throw new HandlerException("Subsystem data must be a structure array.");
var mcosData = mainVariable["MCOS", 0] as Opaque
?? throw new HandlerException("MCOS data must be an opaque object.");
var opaqueData = mcosData.RawData as ICellArray
?? throw new HandlerException("Opaque data must be a cell array.");
var info = (opaqueData[0] as IArrayOf<byte>)?.Data
?? throw new HandlerException("Opaque data info must be a byte array.");
var (offsets, position) = ReadOffsets(info, 0);
var fieldNames = ReadFieldNames(info, position, offsets[1]);
var numberOfClasses = ((offsets[3] - offsets[2]) / 16) - 1;
var classIdToName = ReadClassIdToName(info, offsets, fieldNames, numberOfClasses);
var numberOfEmbeddedObjects = (offsets[4] - offsets[3] - 8) / 16;
var embeddedObjectPositionsToValues = ReadEmbeddedObjectPositionsToValues(info, offsets, numberOfEmbeddedObjects);
var numberOfObjects = ((offsets[5] - offsets[4]) / 24) - 1;
var objectClasses = ReadObjectClassInformations(info, offsets, numberOfObjects);
var numberOfObjectPositions = objectClasses.NumberOfObjectPositions;
var objectPositionsToValues = ReadObjectPositionsToValues(info, offsets, numberOfObjectPositions);
var (classInformation, objectInformation) =
GatherClassAndObjectInformation(
classIdToName,
fieldNames,
objectClasses,
objectPositionsToValues,
embeddedObjectPositionsToValues);
var allFields = objectInformation.Values.SelectMany(obj => obj.FieldLinks.Values);
var data = new Dictionary<int, IArray>();
foreach (var i in allFields)
{
data[i] = TransformOpaqueData(opaqueData[i + 2], subsystemData);
}
return new SubsystemData(classInformation, objectInformation, fieldNames, data);
}
private static Dictionary<int, Dictionary<int, int>> ReadObjectPositionsToValues(byte[] info, int[] offsets, int numberOfObjectPositions)
{
using var stream = new MemoryStream(info, offsets[5], offsets[6] - offsets[5]);
using var reader = new BinaryReader(stream);
return ReadObjectPositionsToValuesMapping(reader, numberOfObjectPositions);
}
private static ObjectClasses ReadObjectClassInformations(byte[] info, int[] offsets, int numberOfObjects)
{
using var stream = new MemoryStream(info, offsets[4], offsets[5] - offsets[4]);
using var reader = new BinaryReader(stream);
return ReadObjectClasses(reader, numberOfObjects);
}
private static Dictionary<int, Dictionary<int, int>> ReadEmbeddedObjectPositionsToValues(byte[] info, int[] offsets, int numberOfEmbeddedObjects)
{
using var stream = new MemoryStream(info, offsets[3], offsets[4] - offsets[3]);
using var reader = new BinaryReader(stream);
return ReadEmbeddedObjectPositionsToValuesMapping(reader, numberOfEmbeddedObjects);
}
private static Dictionary<int, string> ReadClassIdToName(byte[] info, int[] offsets, string[] fieldNames, int numberOfClasses)
{
using var stream = new MemoryStream(info, offsets[2], offsets[3] - offsets[2]);
using var reader = new BinaryReader(stream);
return ReadClassNames(reader, fieldNames, numberOfClasses);
}
private static List<RawVariable> ReadRawVariables(byte[] bytes, SubsystemData subsystemData)
{
using var stream = new MemoryStream(bytes);
using var reader = new BinaryReader(stream);
reader.ReadBytes(8);
return MatFileReader.ReadRawVariables(reader, -1, subsystemData);
}
private static (Dictionary<int, SubsystemData.ClassInfo> classInfos,
Dictionary<int, SubsystemData.ObjectInfo> objectInfos)
GatherClassAndObjectInformation(
Dictionary<int, string> classIdToName,
string[] fieldNames,
ObjectClasses objectClasses,
Dictionary<int, Dictionary<int, int>> objectPositionsToValues,
Dictionary<int, Dictionary<int, int>> embeddedObjectPositionsToValues)
{
var classInfos = new Dictionary<int, SubsystemData.ClassInfo>();
foreach (var classId in classIdToName.Keys)
{
var className = classIdToName[classId];
var fieldIds = new SortedSet<int>();
foreach (var objectPosition in objectPositionsToValues.Keys)
{
var foundClassId = objectClasses.GetClassIdByObjectPosition(objectPosition);
if (foundClassId != classId)
{
continue;
}
foreach (var fieldId in objectPositionsToValues[objectPosition].Keys)
{
fieldIds.Add(fieldId);
}
}
foreach (var objectPosition in embeddedObjectPositionsToValues.Keys)
{
var foundClassId = objectClasses.GetClassIdByEmbeddedObjectPosition(objectPosition);
if (foundClassId != classId)
{
continue;
}
foreach (var fieldId in embeddedObjectPositionsToValues[objectPosition].Keys)
{
fieldIds.Add(fieldId);
}
}
var fieldToIndex = new Dictionary<string, int>();
foreach (var fieldId in fieldIds)
{
fieldToIndex[fieldNames[fieldId - 1]] = fieldId;
}
classInfos[classId] = new SubsystemData.ClassInfo(className, fieldToIndex);
}
var objectInfos = new Dictionary<int, SubsystemData.ObjectInfo>();
foreach (var objectPosition in objectPositionsToValues.Keys)
{
var foundKey = objectClasses.GetKeyByObjectPosition(objectPosition);
objectInfos[foundKey] = new SubsystemData.ObjectInfo(objectPositionsToValues[objectPosition]);
}
foreach (var embeddedObjectPosition in embeddedObjectPositionsToValues.Keys)
{
var foundKey = objectClasses.GetKeyByEmbeddedObjectPosition(embeddedObjectPosition);
objectInfos[foundKey] = new SubsystemData.ObjectInfo(embeddedObjectPositionsToValues[embeddedObjectPosition]);
}
return (classInfos, objectInfos);
}
private static Dictionary<int, string> ReadClassNames(
BinaryReader reader,
string[] fieldNames,
int numberOfClasses)
{
var result = new Dictionary<int, string>();
var indices = new int[numberOfClasses + 1];
for (var i = 0; i <= numberOfClasses; i++)
{
reader.ReadInt32();
indices[i] = reader.ReadInt32();
reader.ReadInt32();
reader.ReadInt32();
}
for (var i = 0; i < numberOfClasses; i++)
{
result[i + 1] = fieldNames[indices[i + 1] - 1];
}
return result;
}
private static Dictionary<int, Dictionary<int, int>> ReadEmbeddedObjectPositionsToValuesMapping(
BinaryReader reader, int numberOfObjects)
{
var result = new Dictionary<int, Dictionary<int, int>>();
reader.ReadBytes(8);
for (var objectPosition = 1; objectPosition <= numberOfObjects; objectPosition++)
{
var a = reader.ReadInt32();
var fieldIndex = reader.ReadInt32();
var c = reader.ReadInt32();
var valueIndex = reader.ReadInt32();
result[objectPosition] = new Dictionary<int, int> { [fieldIndex] = valueIndex };
}
return result;
}
private static string[] ReadFieldNames(byte[] bytes, int startPosition, int numberOfFields)
{
var result = new string[numberOfFields];
var position = startPosition;
for (var i = 0; i < numberOfFields; i++)
{
var list = new List<byte>();
while (bytes[position] != 0)
{
list.Add(bytes[position]);
position++;
}
result[i] = Encoding.ASCII.GetString(list.ToArray());
position++;
}
return result;
}
private static Dictionary<int, int> ReadFieldToFieldDataMapping(BinaryReader reader)
{
var length = reader.ReadInt32();
var result = new Dictionary<int, int>();
for (var i = 0; i < length; i++)
{
var x = reader.ReadInt32();
var y = reader.ReadInt32();
var index = x * y;
var link = reader.ReadInt32();
result[index] = link;
}
return result;
}
private static ObjectClasses ReadObjectClasses(
BinaryReader reader,
int numberOfObjects)
{
var result = new Dictionary<int, ObjectClassInformation>();
var classIdFromObjectPosition = new Dictionary<int, int>();
var classIdFromEmbeddedObjectPosition = new Dictionary<int, int>();
var keyFromObjectPosition = new Dictionary<int, int>();
var keyFromEmbeddedObjectPosition = new Dictionary<int, int>();
reader.ReadBytes(24);
var numberOfObjectPositions = 0;
for (var i = 0; i < numberOfObjects; i++)
{
var classId = reader.ReadInt32();
reader.ReadBytes(8);
var embeddedObjectPosition = reader.ReadInt32();
var objectPosition = reader.ReadInt32();
var loadingOrder = reader.ReadInt32(); // Not used.
classIdFromObjectPosition[objectPosition] = classId;
classIdFromEmbeddedObjectPosition[embeddedObjectPosition] = classId;
keyFromObjectPosition[objectPosition] = i + 1;
keyFromEmbeddedObjectPosition[embeddedObjectPosition] = i + 1;
if (objectPosition != 0)
{
numberOfObjectPositions++;
}
}
return new ObjectClasses(
classIdFromObjectPosition,
classIdFromEmbeddedObjectPosition,
keyFromObjectPosition,
keyFromEmbeddedObjectPosition,
numberOfObjectPositions);
}
private static Dictionary<int, Dictionary<int, int>> ReadObjectPositionsToValuesMapping(
BinaryReader reader,
int numberOfObjects)
{
var result = new Dictionary<int, Dictionary<int, int>>();
reader.ReadBytes(8);
for (var objectPosition = 1; objectPosition <= numberOfObjects; objectPosition++)
{
result[objectPosition] = ReadFieldToFieldDataMapping(reader);
var position = reader.BaseStream.Position;
if (position % 8 != 0)
{
reader.ReadBytes(8 - (int)(position % 8));
}
}
return result;
}
private static (int[] offsets, int newPosition) ReadOffsets(byte[] bytes, int startPosition)
{
var position = startPosition;
var offsets = new List<int>();
while (true)
{
var next = BitConverter.ToInt32(bytes, position);
position += 4;
if (next == bytes.Length)
{
break;
}
offsets.Add(next);
}
return (offsets.ToArray(), 40);
}
private static IArray TransformOpaqueData(IArray array, SubsystemData subsystemData)
{
if (array is MatNumericalArrayOf<uint> uintArray &&
uintArray.Data.Length == 6 &&
uintArray.Data[0] == 3707764736u)
{
return ObjectParser.ParseObject(uintArray, subsystemData);
}
if (array is MatCellArray cellArray)
{
for (var i = 0; i < cellArray.Data.Length; i++)
{
var cell = cellArray.Data[i];
var transformedCell = TransformOpaqueData(cell, subsystemData);
cellArray.Data[i] = transformedCell;
}
}
if (array is MatStructureArray structureArray)
{
var newFields = new Dictionary<string, List<IArray>>();
foreach (var pair in structureArray.Fields)
{
var values = pair.Value;
var transformedValues = new List<IArray>(values.Count);
foreach (var value in values)
{
var transformedValue = TransformOpaqueData(value, subsystemData);
transformedValues.Add(transformedValue);
}
newFields[pair.Key] = transformedValues;
}
foreach (var pair in newFields)
{
structureArray.Fields[pair.Key] = pair.Value;
}
}
return array;
}
private readonly struct ObjectClassInformation
{
public ObjectClassInformation(int embeddedObjectPosition, int objectPosition, int loadingOrder, int classId)
{
EmbeddedObjectPosition = embeddedObjectPosition;
ObjectPosition = objectPosition;
LoadingOrder = loadingOrder;
ClassId = classId;
}
public int ClassId { get; }
public int EmbeddedObjectPosition { get; }
public int LoadingOrder { get; }
public int ObjectPosition { get; }
}
private class ObjectClasses
{
private readonly Dictionary<int, int> _classIdFromObjectPosition;
private readonly Dictionary<int, int> _classIdFromEmbeddedObjectPosition;
private readonly Dictionary<int, int> _keyFromObjectPosition;
private readonly Dictionary<int, int> _keyFromEmbeddedObjectPosition;
public ObjectClasses(
Dictionary<int, int> classIdFromObjectPosition,
Dictionary<int, int> classIdFromEmbeddedObjectPosition,
Dictionary<int, int> keyFromObjectPosition,
Dictionary<int, int> keyFromEmbeddedObjectPosition,
int numberOfObjectPositions)
{
_classIdFromObjectPosition = classIdFromObjectPosition;
_classIdFromEmbeddedObjectPosition = classIdFromEmbeddedObjectPosition;
_keyFromObjectPosition = keyFromObjectPosition;
_keyFromEmbeddedObjectPosition = keyFromEmbeddedObjectPosition;
NumberOfObjectPositions = numberOfObjectPositions;
}
public int NumberOfObjectPositions { get; }
public int GetClassIdByObjectPosition(int objectPosition)
=> _classIdFromObjectPosition[objectPosition];
public int GetClassIdByEmbeddedObjectPosition(int embeddedObjectPosition)
=> _classIdFromEmbeddedObjectPosition[embeddedObjectPosition];
public int GetKeyByObjectPosition(int objectPosition)
=> _keyFromObjectPosition[objectPosition];
public int GetKeyByEmbeddedObjectPosition(int embeddedObjectPosition)
=> _keyFromEmbeddedObjectPosition[embeddedObjectPosition];
}
}
}