// +build windows

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package sys

import (
	"syscall"
	"unsafe"

	"golang.org/x/sys/windows"
)

var (
	modkernel32              = windows.NewLazySystemDLL("kernel32.dll")
	procGlobalMemoryStatusEx = modkernel32.NewProc("GlobalMemoryStatusEx")
)

type memoryStatusEx struct {
	cbSize                  uint32
	dwMemoryLoad            uint32
	ullTotalPhys            uint64 // in bytes
	ullAvailPhys            uint64
	ullTotalPageFile        uint64
	ullAvailPageFile        uint64
	ullTotalVirtual         uint64
	ullAvailVirtual         uint64
	ullAvailExtendedVirtual uint64
}

// GetStats - return system statistics for windows.
func GetStats() (stats Stats, err error) {
	var memInfo memoryStatusEx
	memInfo.cbSize = uint32(unsafe.Sizeof(memInfo))
	if mem, _, _ := procGlobalMemoryStatusEx.Call(uintptr(unsafe.Pointer(&memInfo))); mem == 0 {
		err = syscall.GetLastError()
	} else {
		stats.TotalRAM = memInfo.ullTotalPhys
	}

	return stats, err
}