/// <summary>
/// Reads and validates the header block from the map file.
/// </summary>
/// <param name="readBuffer">
/// the ReadBuffer for the file data. </param>
/// <param name="fileSize">
/// the size of the map file in bytes. </param>
/// <exception cref="IOException">
/// if an error occurs while reading the file. </exception>
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
//ORIGINAL LINE: public void readHeader(MapsforgeSharp.Reader.ReadBuffer readBuffer, long fileSize) throws java.io.IOException
public virtual void ReadHeader(ReadBuffer readBuffer, long fileSize)
{
RequiredFields.ReadMagicByte(readBuffer);
RequiredFields.ReadRemainingHeader(readBuffer);
MapFileInfoBuilder mapFileInfoBuilder = new MapFileInfoBuilder();
RequiredFields.readFileVersion(readBuffer, mapFileInfoBuilder);
RequiredFields.ReadFileSize(readBuffer, fileSize, mapFileInfoBuilder);
RequiredFields.ReadMapDate(readBuffer, mapFileInfoBuilder);
RequiredFields.ReadBoundingBox(readBuffer, mapFileInfoBuilder);
RequiredFields.ReadTilePixelSize(readBuffer, mapFileInfoBuilder);
RequiredFields.ReadProjectionName(readBuffer, mapFileInfoBuilder);
OptionalFields.ReadOptionalFields(readBuffer, mapFileInfoBuilder);
RequiredFields.ReadPoiTags(readBuffer, mapFileInfoBuilder);
RequiredFields.ReadWayTags(readBuffer, mapFileInfoBuilder);
ReadSubFileParameters(readBuffer, fileSize, mapFileInfoBuilder);
this.mapFileInfo = mapFileInfoBuilder.Build();
}
private void ReadSubFileParameters(ReadBuffer readBuffer, long fileSize, MapFileInfoBuilder mapFileInfoBuilder)
{
sbyte numberOfSubFiles = readBuffer.ReadByte();
mapFileInfoBuilder.numberOfSubFiles = numberOfSubFiles;
var tempSubFileParameters = new SubFileParameter[numberOfSubFiles];
zoomLevelMinimum = sbyte.MaxValue;
zoomLevelMaximum = sbyte.MinValue;
for (sbyte currentSubFile = 0; currentSubFile < numberOfSubFiles; ++currentSubFile)
{
var subFileParameterBuilder = new SubFileParameterBuilder();
sbyte baseZoomLevel = readBuffer.ReadByte();
subFileParameterBuilder.BaseZoomLevel = baseZoomLevel;
sbyte zoomLevelMin = readBuffer.ReadByte();
subFileParameterBuilder.ZoomLevelMin = zoomLevelMin;
sbyte zoomLevelMax = readBuffer.ReadByte();
subFileParameterBuilder.ZoomLevelMax = zoomLevelMax;
long startAddress = readBuffer.ReadLong();
subFileParameterBuilder.StartAddress = startAddress;
long indexStartAddress = startAddress;
subFileParameterBuilder.IndexStartAddress = indexStartAddress;
long subFileSize = readBuffer.ReadLong();
subFileParameterBuilder.SubFileSize = subFileSize;
subFileParameterBuilder.BoundingBox = mapFileInfoBuilder.boundingBox;
tempSubFileParameters[currentSubFile] = subFileParameterBuilder.Build();
if (zoomLevelMinimum > tempSubFileParameters[currentSubFile].ZoomLevelMin)
{
zoomLevelMinimum = tempSubFileParameters[currentSubFile].ZoomLevelMin;
mapFileInfoBuilder.zoomLevelMin = zoomLevelMinimum;
}
if (zoomLevelMaximum < tempSubFileParameters[currentSubFile].ZoomLevelMax)
{
zoomLevelMaximum = tempSubFileParameters[currentSubFile].ZoomLevelMax;
mapFileInfoBuilder.zoomLevelMax = zoomLevelMaximum;
}
}
subFileParameters = new SubFileParameter[zoomLevelMaximum + 1];
for (int currentMapFile = 0; currentMapFile < numberOfSubFiles; ++currentMapFile)
{
var subFileParameter = tempSubFileParameters[currentMapFile];
for (sbyte zoomLevel = subFileParameter.ZoomLevelMin; zoomLevel <= subFileParameter.ZoomLevelMax; ++zoomLevel)
{
subFileParameters[zoomLevel] = subFileParameter;
}
}
}
private void ReadSubFileParameters(ReadBuffer readBuffer, long fileSize, MapFileInfoBuilder mapFileInfoBuilder)
{
// get and check the number of sub-files (1 byte)
sbyte numberOfSubFiles = readBuffer.ReadByte();
if (numberOfSubFiles < 1)
{
throw new MapFileException("invalid number of sub-files: " + numberOfSubFiles);
}
mapFileInfoBuilder.numberOfSubFiles = numberOfSubFiles;
SubFileParameter[] tempSubFileParameters = new SubFileParameter[numberOfSubFiles];
this.zoomLevelMinimum = sbyte.MaxValue;
this.zoomLevelMaximum = sbyte.MinValue;
// get and check the information for each sub-file
for (sbyte currentSubFile = 0; currentSubFile < numberOfSubFiles; ++currentSubFile)
{
SubFileParameterBuilder subFileParameterBuilder = new SubFileParameterBuilder();
// get and check the base zoom level (1 byte)
sbyte baseZoomLevel = readBuffer.ReadByte();
if (baseZoomLevel < 0 || baseZoomLevel > BASE_ZOOM_LEVEL_MAX)
{
throw new MapFileException("invalid base zoom level: " + baseZoomLevel);
}
subFileParameterBuilder.BaseZoomLevel = baseZoomLevel;
// get and check the minimum zoom level (1 byte)
sbyte zoomLevelMin = readBuffer.ReadByte();
if (zoomLevelMin < 0 || zoomLevelMin > 22)
{
throw new MapFileException("invalid minimum zoom level: " + zoomLevelMin);
}
subFileParameterBuilder.ZoomLevelMin = zoomLevelMin;
// get and check the maximum zoom level (1 byte)
sbyte zoomLevelMax = readBuffer.ReadByte();
if (zoomLevelMax < 0 || zoomLevelMax > 22)
{
throw new MapFileException("invalid maximum zoom level: " + zoomLevelMax);
}
subFileParameterBuilder.ZoomLevelMax = zoomLevelMax;
// check for valid zoom level range
if (zoomLevelMin > zoomLevelMax)
{
throw new MapFileException("invalid zoom level range: " + zoomLevelMin + SPACE + zoomLevelMax);
}
// get and check the start address of the sub-file (8 bytes)
long startAddress = readBuffer.ReadLong();
if (startAddress < HEADER_SIZE_MIN || startAddress >= fileSize)
{
throw new MapFileException("invalid start address: " + startAddress);
}
subFileParameterBuilder.StartAddress = startAddress;
long indexStartAddress = startAddress;
if (mapFileInfoBuilder.optionalFields.IsDebugFile)
{
// the sub-file has an index signature before the index
indexStartAddress += SIGNATURE_LENGTH_INDEX;
}
subFileParameterBuilder.IndexStartAddress = indexStartAddress;
// get and check the size of the sub-file (8 bytes)
long subFileSize = readBuffer.ReadLong();
if (subFileSize < 1)
{
throw new MapFileException("invalid sub-file size: " + subFileSize);
}
subFileParameterBuilder.SubFileSize = subFileSize;
subFileParameterBuilder.BoundingBox = mapFileInfoBuilder.boundingBox;
// add the current sub-file to the list of sub-files
tempSubFileParameters[currentSubFile] = subFileParameterBuilder.Build();
// update the global minimum and maximum zoom level information
if (this.zoomLevelMinimum > tempSubFileParameters[currentSubFile].ZoomLevelMin)
{
this.zoomLevelMinimum = tempSubFileParameters[currentSubFile].ZoomLevelMin;
mapFileInfoBuilder.zoomLevelMin = this.zoomLevelMinimum;
}
if (this.zoomLevelMaximum < tempSubFileParameters[currentSubFile].ZoomLevelMax)
{
this.zoomLevelMaximum = tempSubFileParameters[currentSubFile].ZoomLevelMax;
mapFileInfoBuilder.zoomLevelMax = this.zoomLevelMaximum;
}
}
// create and fill the lookup table for the sub-files
this.subFileParameters = new SubFileParameter[this.zoomLevelMaximum + 1];
for (int currentMapFile = 0; currentMapFile < numberOfSubFiles; ++currentMapFile)
{
SubFileParameter subFileParameter = tempSubFileParameters[currentMapFile];
for (sbyte zoomLevel = subFileParameter.ZoomLevelMin; zoomLevel <= subFileParameter.ZoomLevelMax; ++zoomLevel)
{
this.subFileParameters[zoomLevel] = subFileParameter;
}
}
}
