private void AddPacketToPages(TeletextPacket packet)
{
//add this packet to the magazines and their pages associated with this service
if (!Pages.ContainsKey(_currentPageNumber))
{
Pages.Add(_currentPageNumber, new TeletextPage {
ParentMagazine = this, PageNum = _currentPageNumber
});
}
Pages[_currentPageNumber].AddPacket(packet);
}
public TeletextHeaderPacket(TeletextPacket basePacket) : base(basePacket)
{
if (basePacket.Row != 0)
{
throw new InvalidDataException("Non-header packet passed to constructor of header packet class");
}
Page = (ushort)((Utils.UnHam84(Data[7]) << 4) + Utils.UnHam84(Data[6]));
EraseFlag = (Utils.UnHam84(Data[9]) & 0x08) == 8;
Subcode = (Utils.UnHam84(Data[11]) << 24) + (Utils.UnHam84(Data[10]) << 16) + (Utils.UnHam84(Data[9]) << 8) + Utils.UnHam84(Data[8]);
}
public void AddPacket(TeletextPacket packet)
{
if (packet.Magazine != MagazineNum)
{
throw new InvalidDataException($"Packet for magazine {packet.Magazine} added to magazine {MagazineNum}");
}
if (packet.Row == 29)
{
//this is a magazine-specific packet, which should set some over-rideable defaults for any pages
//TODO: This
return;
}
//ETS 300 706, 9.3.1
var headerPacket = packet as TeletextHeaderPacket;
if (headerPacket != null)
{
//row 0 is the 'header' row, and has some extra control non-display data at start of the data
//check if a pre-existing page within this magazine was set, and is now terminated by this new header
if (_currentPageNumber != -1 && Pages.ContainsKey(_currentPageNumber))
{
var completedPage = Pages[_currentPageNumber];
if (completedPage != null)
{
ParentService.OnTeletextPageReady(completedPage);
}
}
_currentPageNumber = headerPacket.Page;
if (ParentService.PageFilter != -1 && headerPacket.Page != ParentService.PageFilter)
{
return;
}
if (_currentPageNumber == 0x8EE || _currentPageNumber == 0x8FF || !headerPacket.EraseFlag)
{
return;
}
if (!Pages.ContainsKey(_currentPageNumber))
{
return;
}
Pages[_currentPageNumber].Clear();
ParentService.OnTeletextPageCleared(_currentPageNumber, packet.Pts);
}
else
{
if (ParentService.PageFilter != -1 && _currentPageNumber != ParentService.PageFilter)
{
return;
}
//any remaining row addresses are page-specific, and shall be processed within that page
AddPacketToPages(packet);
}
}
