/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            memchecker.cc
 *
 *  Sat Jan 16 18:27:52 CET 2016
 *  Copyright 2016 Andr� Nusser
 *  andre.nusser@googlemail.com
 ****************************************************************************/

/*
 *  This file is part of DrumGizmo.
 *
 *  DrumGizmo is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  DrumGizmo is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with DrumGizmo; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "memchecker.h"

#include "platform.h"

#if DG_PLATFORM == DG_PLATFORM_LINUX
#include <sys/sysinfo.h>
#elif DG_PLATFORM == DG_PLATFORM_OSX
#include <mach/vm_statistics.h>
#include <mach/mach_types.h>
#include <mach/mach_init.h>
#include <mach/mach_host.h>
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/vmmeter.h>
#endif

#include <sndfile.h>
#include <hugin.hpp>

bool MemChecker::enoughFreeMemory(const DrumKit& drumkit) const
{
	uint64_t free_memory = calcFreeMemory();
	uint64_t needed_memory = calcNeededMemory(drumkit);

	return free_memory >= needed_memory;
}

uint64_t MemChecker::calcFreeMemory() const
{
	uint64_t free_memory = 0;

	// Platform specific calculation of the amount of free memory.
#if DG_PLATFORM == DG_PLATFORM_LINUX
	struct sysinfo sys_info;
	sysinfo(&sys_info);
	free_memory = sys_info.freeram * sys_info.mem_unit;
#elif DG_PLATFORM == DG_PLATFORM_WINDOWS
	MEMORYSTATUSEX status;
	status.dwLength = sizeof(status);
	GlobalMemoryStatusEx(&status);
	free_memory = status.ullAvailPhys;
#elif DG_PLATFORM == DG_PLATFORM_OSX
	vm_size_t page_size;
	vm_statistics64_data_t vm_stats;
	mach_port_t mach_port = mach_host_self();
	mach_msg_type_number_t count = sizeof(vm_stats) / sizeof(natural_t);

	if (KERN_SUCCESS == host_page_size(mach_port, &page_size) &&
	    KERN_SUCCESS == host_statistics64(mach_port, HOST_VM_INFO, (host_info64_t)&vm_stats, &count))
	{
		free_memory = (uint64_t)vm_stats.free_count * (uint64_t)page_size;
	}
#elif DG_PLATFORM == DG_PLATFORM_FREEBSD
	u_int page_size;
	struct vmtotal vmt;
	size_t vmt_size, uint_size;

	vmt_size = sizeof(vmt);
	uint_size = sizeof(page_size);

	sysctlbyname("vm.vmtotal", &vmt, &vmt_size, NULL, 0);
	sysctlbyname("vm.stats.vm.v_page_size", &page_size, &uint_size, NULL, 0);

	free_memory = vmt.t_free * (u_int64_t)page_size;
#elif DG_PLATFORM == DG_PLATFORM_UNIX
	// TODO
#endif

	DEBUG(memchecker, "Calculated %" PRIu64 " free memory.\n", free_memory);

	return free_memory;
}

uint64_t MemChecker::calcNeededMemory(const DrumKit& drumkit) const
{
	uint64_t needed_memory = 0;

	// Calculate memory usage of all instruments of drumkit.
	for(auto& instr_ptr: drumkit.instruments)
	{
		const auto& audiofiles = instr_ptr->audiofiles;

		// Calculate memory usage of all audiofiles.
		for(auto& audiofile: audiofiles)
		{
			needed_memory += calcBytesPerChannel(audiofile->filename);
		}
	}

	DEBUG(memchecker, "Calculated %" PRIu64 " needed memory.\n", needed_memory);

	return needed_memory;
}

uint64_t MemChecker::calcBytesPerChannel(const std::string& filename) const
{
	SF_INFO sf_info{};

	SNDFILE* f = sf_open(filename.c_str(), SFM_READ, &sf_info);
	if(!f)
	{
		ERR(memchecker, "SNDFILE Error (%s): %s\n",
		    filename.c_str(), sf_strerror(f));
		return 0;
	}

	sf_close(f);

	return sf_info.frames * sizeof(sample_t);
}