/*
 * Copyright 2019, Ryan Leavengood.
 * Copyright 2009, Axel Dörfler, axeld@pinc-software.de.
 * Copyright 2002, Marcus Overhagen. All Rights Reserved.
 * Distributed under the terms of the MIT License.
 */


//! A cache for BBuffers to be received by BBufferConsumer::BufferReceived().


#include "BufferCache.h"

#include <Buffer.h>

#include "MediaDebug.h"
#include "MediaMisc.h"
#include "SharedBufferList.h"


namespace BPrivate {


BufferCache::BufferCache()
{
}


BufferCache::~BufferCache()
{
	BufferMap::Iterator iterator = fMap.GetIterator();
	while (iterator.HasNext()) {
		BufferMap::Entry entry = iterator.Next();
		delete entry.value.buffer;
	}
}


BBuffer*
BufferCache::GetBuffer(media_buffer_id id, port_id port)
{
	if (id <= 0)
		return NULL;

	buffer_cache_entry* existing;
	if (fMap.Get(id, existing)) {
		existing->buffer->fFlags |= BUFFER_TO_RECLAIM;
		return existing->buffer;
	}

	buffer_clone_info info;
	info.buffer = id;
	BBuffer* buffer = new(std::nothrow) BBuffer(info);
	if (buffer == NULL || buffer->ID() <= 0
			|| buffer->Data() == NULL) {
		delete buffer;
		return NULL;
	}

	if (buffer->ID() != id)
		debugger("BufferCache::GetBuffer: IDs mismatch");

	buffer_cache_entry entry;
	entry.buffer = buffer;
	entry.port = port;
	status_t error = fMap.Put(id, entry);
	if (error != B_OK) {
		delete buffer;
		return NULL;
	}

	buffer->fFlags |= BUFFER_TO_RECLAIM;
	return buffer;
}


void
BufferCache::FlushCacheForPort(port_id port)
{
	BufferMap::Iterator iterator = fMap.GetIterator();
	while (iterator.HasNext()) {
		BufferMap::Entry entry = iterator.Next();
		if (entry.value.port == port) {
			BBuffer* buffer = entry.value.buffer;
			bool isReclaimed = (buffer->fFlags & BUFFER_TO_RECLAIM) == 0;
			if (isReclaimed && buffer->fBufferList != NULL)
				isReclaimed = buffer->fBufferList->RemoveBuffer(buffer) == B_OK;

			if (isReclaimed)
				delete buffer;
			else {
				// mark the buffer for deletion
				buffer->fFlags |= BUFFER_MARKED_FOR_DELETION;
			}
			// Then remove it from the map
			fMap.Remove(iterator);
		}
	}
}


}	// namespace BPrivate