--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/foosdk/sdk/foobar2000/SDK/file_cached_impl.cpp	Mon Jan 05 02:15:46 2026 -0500
@@ -0,0 +1,398 @@
+#include "foobar2000-sdk-pch.h"
+#include "filesystem.h"
+namespace {
+
+#define FILE_CACHED_DEBUG_LOG 0
+
+class file_cached_impl_v2 : public service_multi_inherit< file_v2, service_multi_inherit< file_cached, file_lowLevelIO > > {
+public:
+	enum {minBlockSize = 4096};
+	enum {maxSkipSize = 128*1024};
+	file_cached_impl_v2(size_t maxBlockSize) : m_maxBlockSize(maxBlockSize) {
+		//m_buffer.set_size(blocksize);
+	}
+	size_t get_cache_block_size() override {return m_maxBlockSize;}
+	void suggest_grow_cache(size_t suggestSize) override {
+		if (m_maxBlockSize < suggestSize) m_maxBlockSize = suggestSize;
+	}
+
+	void initialize(service_ptr_t<file> p_base,abort_callback & p_abort) {
+		m_base = p_base;
+		m_can_seek = m_base->can_seek();
+		_reinit(p_abort);
+	}
+	t_filestats2 get_stats2(uint32_t f, abort_callback& a) override {
+		flush_buffer();
+		return m_base->get_stats2_(f, a);
+	}
+	size_t lowLevelIO(const GUID & guid, size_t arg1, void * arg2, size_t arg2size, abort_callback & abort) override {
+		abort.check();
+		file_lowLevelIO::ptr ll;
+		if ( ll &= m_base ) {
+			flush_buffer();
+			return ll->lowLevelIO(guid, arg1, arg2, arg2size, abort );
+		}
+		return 0;
+	}
+private:
+	void _reinit(abort_callback & p_abort) {
+		m_position = 0;
+		
+		if (m_can_seek) {
+			m_position_base = m_base->get_position(p_abort);
+		} else {
+			m_position_base = 0;
+		}
+
+		m_size = m_base->get_size(p_abort);
+
+		flush_buffer();
+	}
+public:
+
+	t_filesize skip(t_filesize p_bytes,abort_callback & p_abort) override {
+		if (p_bytes > maxSkipSize) {
+			const t_filesize size = get_size(p_abort);
+			if (size != filesize_invalid) {
+				const t_filesize position = get_position(p_abort);
+				const t_filesize toskip = pfc::min_t( p_bytes, size - position );
+				seek(position + toskip,p_abort);
+				return toskip;
+			}
+		}
+		return skip_( p_bytes, p_abort );
+	}
+	t_filesize skip_(t_filesize p_bytes,abort_callback & p_abort) {
+#if FILE_CACHED_DEBUG_LOG
+		FB2K_DebugLog() << "Skipping bytes: " << p_bytes;
+#endif
+		t_filesize todo = p_bytes;
+		for(;;) {
+			size_t inBuffer = this->bufferRemaining();
+			size_t delta = (size_t) pfc::min_t<t_filesize>(inBuffer, todo);
+			m_bufferReadPtr += delta;
+			m_position += delta;
+			todo -= delta;
+			if (todo == 0) break;
+			p_abort.check();
+			this->m_bufferState = 0; // null it early to leave in a consistent state if base read fails
+			this->m_bufferReadPtr = 0;
+			baseSeek(m_position,p_abort);
+			m_readSize = pfc::min_t<size_t>(m_readSize << 1, this->m_maxBlockSize);
+			if (m_readSize < minBlockSize) m_readSize = minBlockSize;
+#if FILE_CACHED_DEBUG_LOG
+			FB2K_DebugLog() << "Growing read size: " << m_readSize;
+#endif
+			m_buffer.grow_size(m_readSize);
+			m_bufferState = m_base->read(m_buffer.get_ptr(), m_readSize, p_abort);
+			if (m_bufferState == 0) break;
+			m_position_base += m_bufferState;
+		}
+
+		return p_bytes - todo;
+	}
+
+	t_size read(void * p_buffer,t_size p_bytes,abort_callback & p_abort) override {
+#if FILE_CACHED_DEBUG_LOG
+		FB2K_DebugLog() << "Reading bytes: " << p_bytes;
+#endif
+		t_uint8 * outptr = (t_uint8*)p_buffer;
+		size_t todo = p_bytes;
+		for(;;) {
+			size_t inBuffer = this->bufferRemaining();
+			size_t delta = pfc::min_t<size_t>(inBuffer, todo);
+			memcpy(outptr, this->m_buffer.get_ptr() + m_bufferReadPtr, delta);
+			m_bufferReadPtr += delta;
+			m_position += delta;
+			todo -= delta;
+			if (todo == 0) break;
+			p_abort.check();
+			outptr += delta;
+			this->m_bufferState = 0; // null it early to leave in a consistent state if base read fails
+			this->m_bufferReadPtr = 0;
+			baseSeek(m_position,p_abort);
+			m_readSize = pfc::min_t<size_t>(m_readSize << 1, this->m_maxBlockSize);
+			if (m_readSize < minBlockSize) m_readSize = minBlockSize;
+#if FILE_CACHED_DEBUG_LOG
+			FB2K_DebugLog() << "Growing read size: " << m_readSize;
+#endif
+			m_buffer.grow_size(m_readSize);
+			m_bufferState = m_base->read(m_buffer.get_ptr(), m_readSize, p_abort);
+			if (m_bufferState == 0) break;
+			m_position_base += m_bufferState;
+		}
+
+		return p_bytes - todo;
+	}
+
+	void write(const void * p_buffer,t_size p_bytes,abort_callback & p_abort) override {
+#if FILE_CACHED_DEBUG_LOG
+		FB2K_DebugLog() << "Writing bytes: " << p_bytes;
+#endif
+		p_abort.check();
+		baseSeek(m_position,p_abort);
+		m_base->write(p_buffer,p_bytes,p_abort);
+		m_position_base = m_position = m_position + p_bytes;
+		if (m_size < m_position) m_size = m_position;
+		flush_buffer();
+	}
+
+	t_filesize get_size(abort_callback & p_abort) override {
+		p_abort.check();
+		return m_size;
+	}
+	t_filesize get_position(abort_callback & p_abort) override {
+		p_abort.check();
+		PFC_ASSERT( m_position <= m_size );
+		return m_position;
+	}
+	void set_eof(abort_callback & p_abort) {
+		p_abort.check();
+		baseSeek(m_position,p_abort);
+		m_base->set_eof(p_abort);
+		flush_buffer();
+	}
+	void seek(t_filesize p_position,abort_callback & p_abort) override {
+#if FILE_CACHED_DEBUG_LOG
+		FB2K_DebugLog() << "Seeking: " << p_position;
+#endif
+		p_abort.check();
+		if (!m_can_seek) throw exception_io_object_not_seekable();
+		if (p_position > m_size) throw exception_io_seek_out_of_range();
+		int64_t delta = p_position - m_position;
+
+		// special case
+		if (delta >= 0 && delta <= this->minBlockSize) {
+#if FILE_CACHED_DEBUG_LOG
+			FB2K_DebugLog() << "Skip-seeking: " << p_position;
+#endif
+			t_filesize skipped = this->skip_( delta, p_abort );
+			PFC_ASSERT( skipped == (t_filesize)delta ); (void) skipped;
+			return;
+		}
+
+		m_position = p_position;
+		// within currently buffered data?
+		if ((delta >= 0 && (uint64_t) delta <= bufferRemaining()) || (delta < 0 && (uint64_t)(-delta) <= m_bufferReadPtr)) {
+#if FILE_CACHED_DEBUG_LOG
+			FB2K_DebugLog() << "Quick-seeking: " << p_position;
+#endif
+			m_bufferReadPtr += (ptrdiff_t)delta;
+		} else {
+#if FILE_CACHED_DEBUG_LOG
+			FB2K_DebugLog() << "Slow-seeking: " << p_position;
+#endif
+			this->flush_buffer();
+		}
+	}
+	void reopen(abort_callback & p_abort) override {
+		if (this->m_can_seek) {
+			seek(0,p_abort);
+		} else {
+			this->m_base->reopen( p_abort );
+			this->_reinit( p_abort );
+		}
+	}
+	bool can_seek() override {return m_can_seek;}
+	bool get_content_type(pfc::string_base & out) override {return m_base->get_content_type(out);}
+	void on_idle(abort_callback & p_abort) override {p_abort.check();m_base->on_idle(p_abort);}
+	t_filetimestamp get_timestamp(abort_callback & p_abort) override {p_abort.check(); return m_base->get_timestamp(p_abort);}
+	bool is_remote() override {return m_base->is_remote();}
+	void resize(t_filesize p_size,abort_callback & p_abort) override {
+		flush_buffer();
+		m_base->resize(p_size,p_abort);
+		m_size = p_size;
+		if (m_position > m_size) m_position = m_size;
+		if (m_position_base > m_size) m_position_base = m_size;
+	}
+private:
+	size_t bufferRemaining() const {return m_bufferState - m_bufferReadPtr;}
+	void baseSeek(t_filesize p_target,abort_callback & p_abort) {
+		if (p_target != m_position_base) {
+			m_base->seek(p_target,p_abort);
+			m_position_base = p_target;
+		}
+	}
+
+	void flush_buffer() {
+		m_bufferState = m_bufferReadPtr = 0;
+		m_readSize = 0;
+	}
+
+	service_ptr_t<file> m_base;
+	t_filesize m_position,m_position_base,m_size;
+	bool m_can_seek;
+	size_t m_bufferState, m_bufferReadPtr;
+	pfc::array_t<t_uint8> m_buffer;
+	size_t m_maxBlockSize;
+	size_t m_readSize;
+};
+
+class file_cached_impl : public service_multi_inherit< file_v2, service_multi_inherit< file_cached, file_lowLevelIO > > {
+public:
+	file_cached_impl(t_size blocksize) {
+		m_buffer.set_size(blocksize);
+	}
+	size_t get_cache_block_size() override {return m_buffer.get_size();}
+	void suggest_grow_cache(size_t) override {}
+	void initialize(service_ptr_t<file> p_base,abort_callback & p_abort) {
+		m_base = p_base;
+		m_can_seek = m_base->can_seek();
+		_reinit(p_abort);
+	}
+private:
+	void _reinit(abort_callback & p_abort) {
+		m_position = 0;
+		
+		if (m_can_seek) {
+			m_position_base = m_base->get_position(p_abort);
+		} else {
+			m_position_base = 0;
+		}
+
+		m_size = m_base->get_size(p_abort);
+
+		flush_buffer();
+	}
+public:
+	t_filestats2 get_stats2(uint32_t f, abort_callback& a) override {
+		flush_buffer();
+		return m_base->get_stats2_(f, a);
+	}
+	size_t lowLevelIO(const GUID & guid, size_t arg1, void * arg2, size_t arg2size, abort_callback & abort) override {
+		abort.check();
+		file_lowLevelIO::ptr ll;
+		if ( ll &= m_base ) {
+			flush_buffer();
+			return ll->lowLevelIO(guid, arg1, arg2, arg2size, abort);
+		}
+		return 0;
+	}
+	t_size read(void * p_buffer,t_size p_bytes,abort_callback & p_abort) override {
+		t_uint8 * outptr = (t_uint8*)p_buffer;
+		t_size done = 0;
+		while(done < p_bytes && m_position < m_size) {
+			p_abort.check();
+
+			if (m_position >= m_buffer_position && m_position < m_buffer_position + m_buffer_status) {				
+				t_size delta = pfc::min_t<t_size>((t_size)(m_buffer_position + m_buffer_status - m_position),p_bytes - done);
+				t_size bufptr = (t_size)(m_position - m_buffer_position);
+				memcpy(outptr+done,m_buffer.get_ptr()+bufptr,delta);
+				done += delta;
+				m_position += delta;
+				if (m_buffer_status != m_buffer.get_size() && done < p_bytes) break;//EOF before m_size is hit
+			} else {
+				m_buffer_position = m_position - m_position % m_buffer.get_size();
+				baseSeek(m_buffer_position,p_abort);
+
+				m_buffer_status = m_base->read(m_buffer.get_ptr(),m_buffer.get_size(),p_abort);
+				m_position_base += m_buffer_status;
+
+				if (m_buffer_status <= (t_size)(m_position - m_buffer_position)) break;
+			}
+		}
+
+		return done;
+	}
+
+	void write(const void * p_buffer,t_size p_bytes,abort_callback & p_abort) override {
+		p_abort.check();
+		baseSeek(m_position,p_abort);
+		m_base->write(p_buffer,p_bytes,p_abort);
+		m_position_base = m_position = m_position + p_bytes;
+		if (m_size < m_position) m_size = m_position;
+		flush_buffer();
+	}
+
+	t_filesize get_size(abort_callback & p_abort) override {
+		p_abort.check();
+		return m_size;
+	}
+	t_filesize get_position(abort_callback & p_abort) override {
+		p_abort.check();
+		return m_position;
+	}
+	void set_eof(abort_callback & p_abort) {
+		p_abort.check();
+		baseSeek(m_position,p_abort);
+		m_base->set_eof(p_abort);
+		flush_buffer();
+	}
+	void seek(t_filesize p_position,abort_callback & p_abort) override {
+		p_abort.check();
+		if (!m_can_seek) throw exception_io_object_not_seekable();
+		if (p_position > m_size) throw exception_io_seek_out_of_range();
+		m_position = p_position;
+	}
+	void reopen(abort_callback & p_abort) override {
+		if (this->m_can_seek) {
+			seek(0,p_abort);
+		} else {
+			this->m_base->reopen( p_abort );
+			this->_reinit( p_abort );
+		}
+	}
+	bool can_seek() override {return m_can_seek;}
+	bool get_content_type(pfc::string_base & out) override {return m_base->get_content_type(out);}
+	void on_idle(abort_callback & p_abort) override {p_abort.check();m_base->on_idle(p_abort);}
+	t_filetimestamp get_timestamp(abort_callback & p_abort) override {p_abort.check(); return m_base->get_timestamp(p_abort);}
+	bool is_remote() override {return m_base->is_remote();}
+	void resize(t_filesize p_size,abort_callback & p_abort) override {
+		flush_buffer();
+		m_base->resize(p_size,p_abort);
+		m_size = p_size;
+		if (m_position > m_size) m_position = m_size;
+		if (m_position_base > m_size) m_position_base = m_size;
+	}
+private:
+	void baseSeek(t_filesize p_target,abort_callback & p_abort) {
+		if (p_target != m_position_base) {
+			m_base->seek(p_target,p_abort);
+			m_position_base = p_target;
+		}
+	}
+
+	void flush_buffer() {
+		m_buffer_status = 0;
+		m_buffer_position = 0;
+	}
+
+	service_ptr_t<file> m_base;
+	t_filesize m_position,m_position_base,m_size;
+	bool m_can_seek;
+	t_filesize m_buffer_position;
+	t_size m_buffer_status;
+	pfc::array_t<t_uint8> m_buffer;
+};
+
+}
+
+file::ptr file_cached::g_create(service_ptr_t<file> p_base,abort_callback & p_abort, t_size blockSize) {
+
+	if (p_base->is_in_memory()) {
+		return p_base; // do not want
+	}
+
+	{ // do not duplicate cache layers, check if the file we're being handed isn't already cached
+		file_cached::ptr c;
+		if (p_base->service_query_t(c)) {
+			c->suggest_grow_cache(blockSize);
+			return p_base;
+		}
+	}
+
+	auto obj = fb2k::service_new< file_cached_impl_v2 >(blockSize);
+	obj->initialize(p_base,p_abort);
+	file_v2* asdf = obj.get_ptr();
+	return asdf;
+}
+
+void file_cached::g_create(service_ptr_t<file> & p_out,service_ptr_t<file> p_base,abort_callback & p_abort, t_size blockSize) {
+	p_out = g_create(p_base, p_abort, blockSize);
+}
+
+void file_cached::g_decodeInitCache(file::ptr & theFile, abort_callback & abort, size_t blockSize) {
+	if (theFile->is_remote() || !theFile->can_seek()) return;
+
+	g_create(theFile, theFile, abort, blockSize);
+}