#include "stdafx.h"
#include "OggFile.h"

COggFile::COggFile(IAsyncReader* pAsyncReader, HRESULT& hr)
	: CBaseSplitterFile(pAsyncReader, hr, DEFAULT_CACHE_LENGTH, false)
{
	if(FAILED(hr)) {
		return;
	}
	hr = Init();
}

HRESULT COggFile::Init()
{
	Seek(0);
	if(!Sync()) {
		return E_FAIL;
	}

	return S_OK;
}

bool COggFile::Sync(HANDLE hBreak)
{
	__int64 start = GetPos();

	DWORD dw;
	for(__int64 i = 0, j = hBreak ? GetLength() - start : 65536;
			i < j && S_OK == ByteRead((BYTE*)&dw, sizeof(dw))
			&& ((i&0xffff) || !hBreak || WaitForSingleObject(hBreak, 0) != WAIT_OBJECT_0);
			i++, Seek(start + i)) {
		if(dw == 'SggO') {
			Seek(start + i);
			return(true);
		}
	}

	Seek(start);

	return(false);
}

bool COggFile::Read(OggPageHeader& hdr, HANDLE hBreak)
{
	return Sync(hBreak) && S_OK == ByteRead((BYTE*)&hdr, sizeof(hdr)) && hdr.capture_pattern == 'SggO';
}

bool COggFile::Read(OggPage& page, bool fFull, HANDLE hBreak)
{
	memset(&page.m_hdr, 0, sizeof(page.m_hdr));
	page.m_lens.RemoveAll();
	page.SetCount(0);

	if(!Read(page.m_hdr, hBreak)) {
		return(false);
	}

	int pagelen = 0, packetlen = 0;
	for(BYTE i = 0; i < page.m_hdr.number_page_segments; i++) {
		BYTE b;
		if(S_OK != ByteRead(&b, 1)) {
			return(false);
		}
		packetlen += b;
		if(1/*b < 0xff*/) {
			page.m_lens.AddTail(packetlen);
			pagelen += packetlen;
			packetlen = 0;
		}
	}

	if(fFull) {
		page.SetCount(pagelen);
		if(S_OK != ByteRead(page.GetData(), page.GetCount())) {
			return(false);
		}
	} else {
		Seek(GetPos() + pagelen);
		page.m_lens.RemoveAll();
	}

	return(true);
}