package daemon

import (
	"os"
	"runtime"
	"time"

	"github.com/Sirupsen/logrus"
	"github.com/docker/docker/api/types"
	"github.com/docker/docker/autogen/dockerversion"
	"github.com/docker/docker/context"
	"github.com/docker/docker/pkg/fileutils"
	"github.com/docker/docker/pkg/parsers/kernel"
	"github.com/docker/docker/pkg/parsers/operatingsystem"
	"github.com/docker/docker/pkg/sysinfo"
	"github.com/docker/docker/pkg/system"
	"github.com/docker/docker/registry"
	"github.com/docker/docker/utils"
)

// SystemInfo returns information about the host server the daemon is running on.
func (daemon *Daemon) SystemInfo(ctx context.Context) (*types.Info, error) {
	images := daemon.Graph(ctx).Map()
	var imgcount int
	if images == nil {
		imgcount = 0
	} else {
		imgcount = len(images)
	}
	kernelVersion := "<unknown>"
	if kv, err := kernel.GetKernelVersion(); err == nil {
		kernelVersion = kv.String()
	}

	operatingSystem := "<unknown>"
	if s, err := operatingsystem.GetOperatingSystem(); err == nil {
		operatingSystem = s
	}

	// Don't do containerized check on Windows
	if runtime.GOOS != "windows" {
		if inContainer, err := operatingsystem.IsContainerized(); err != nil {
			logrus.Errorf("Could not determine if daemon is containerized: %v", err)
			operatingSystem += " (error determining if containerized)"
		} else if inContainer {
			operatingSystem += " (containerized)"
		}
	}

	meminfo, err := system.ReadMemInfo()
	if err != nil {
		logrus.Errorf("Could not read system memory info: %v", err)
	}

	// if we still have the original dockerinit binary from before
	// we copied it locally, let's return the path to that, since
	// that's more intuitive (the copied path is trivial to derive
	// by hand given VERSION)
	initPath := utils.DockerInitPath("")
	if initPath == "" {
		// if that fails, we'll just return the path from the daemon
		initPath = daemon.systemInitPath()
	}

	sysInfo := sysinfo.New(false)

	v := &types.Info{
		ID:                 daemon.ID,
		Containers:         len(daemon.List(ctx)),
		Images:             imgcount,
		Driver:             daemon.GraphDriver(ctx).String(),
		DriverStatus:       daemon.GraphDriver(ctx).Status(),
		IPv4Forwarding:     !sysInfo.IPv4ForwardingDisabled,
		BridgeNfIptables:   !sysInfo.BridgeNfCallIptablesDisabled,
		BridgeNfIP6tables:  !sysInfo.BridgeNfCallIP6tablesDisabled,
		Debug:              os.Getenv("DEBUG") != "",
		NFd:                fileutils.GetTotalUsedFds(),
		NGoroutines:        runtime.NumGoroutine(),
		SystemTime:         time.Now().Format(time.RFC3339Nano),
		ExecutionDriver:    daemon.ExecutionDriver(ctx).Name(),
		LoggingDriver:      daemon.defaultLogConfig.Type,
		NEventsListener:    daemon.EventsService.SubscribersCount(),
		KernelVersion:      kernelVersion,
		OperatingSystem:    operatingSystem,
		IndexServerAddress: registry.IndexServer,
		RegistryConfig:     daemon.RegistryService.Config,
		InitSha1:           dockerversion.INITSHA1,
		InitPath:           initPath,
		NCPU:               runtime.NumCPU(),
		MemTotal:           meminfo.MemTotal,
		DockerRootDir:      daemon.config().Root,
		Labels:             daemon.config().Labels,
		ExperimentalBuild:  utils.ExperimentalBuild(),
		ServerVersion:      dockerversion.VERSION,
	}

	// TODO Windows. Refactor this more once sysinfo is refactored into
	// platform specific code. On Windows, sysinfo.cgroupMemInfo and
	// sysinfo.cgroupCpuInfo will be nil otherwise and cause a SIGSEGV if
	// an attempt is made to access through them.
	if runtime.GOOS != "windows" {
		v.MemoryLimit = sysInfo.MemoryLimit
		v.SwapLimit = sysInfo.SwapLimit
		v.OomKillDisable = sysInfo.OomKillDisable
		v.CPUCfsPeriod = sysInfo.CPUCfsPeriod
		v.CPUCfsQuota = sysInfo.CPUCfsQuota
	}

	if httpProxy := os.Getenv("http_proxy"); httpProxy != "" {
		v.HTTPProxy = httpProxy
	}
	if httpsProxy := os.Getenv("https_proxy"); httpsProxy != "" {
		v.HTTPSProxy = httpsProxy
	}
	if noProxy := os.Getenv("no_proxy"); noProxy != "" {
		v.NoProxy = noProxy
	}
	if hostname, err := os.Hostname(); err == nil {
		v.Name = hostname
	}

	return v, nil
}