package main

import (
	"fmt"
	"html/template"
	"os"
	"reflect"
	"sort"
	"strconv"
	"strings"
	"text/tabwriter"
	"time"

	tm "github.com/buger/goterm"
	"github.com/containers/buildah/pkg/formats"
	"github.com/containers/libpod/cmd/podman/cliconfig"
	"github.com/containers/libpod/cmd/podman/libpodruntime"
	"github.com/containers/libpod/cmd/podman/shared"
	"github.com/containers/libpod/libpod"
	"github.com/containers/libpod/pkg/rootless"
	"github.com/containers/libpod/pkg/util"
	"github.com/docker/go-units"
	"github.com/opentracing/opentracing-go"
	"github.com/pkg/errors"
	"github.com/sirupsen/logrus"
	"github.com/spf13/cobra"
)

const (
	hid      = "CONTAINER ID"
	himage   = "IMAGE"
	hcommand = "COMMAND"
	hcreated = "CREATED"
	hstatus  = "STATUS"
	hports   = "PORTS"
	hnames   = "NAMES"
	hsize    = "SIZE"
	hpod     = "POD"
	nspid    = "PID"
	nscgroup = "CGROUPNS"
	nsipc    = "IPC"
	nsmnt    = "MNT"
	nsnet    = "NET"
	nspidns  = "PIDNS"
	nsuserns = "USERNS"
	nsuts    = "UTS"
)

type psTemplateParams struct {
	ID            string
	Image         string
	Command       string
	CreatedAtTime time.Time
	Created       string
	Status        string
	Ports         string
	Size          string
	Names         string
	Labels        string
	Mounts        string
	PID           int
	CGROUPNS      string
	IPC           string
	MNT           string
	NET           string
	PIDNS         string
	USERNS        string
	UTS           string
	Pod           string
	IsInfra       bool
}

// Type declaration and functions for sorting the PS output
type psSorted []shared.PsContainerOutput

func (a psSorted) Len() int      { return len(a) }
func (a psSorted) Swap(i, j int) { a[i], a[j] = a[j], a[i] }

type psSortedCommand struct{ psSorted }

func (a psSortedCommand) Less(i, j int) bool {
	return a.psSorted[i].Command < a.psSorted[j].Command
}

type psSortedCreated struct{ psSorted }

func (a psSortedCreated) Less(i, j int) bool {
	return a.psSorted[i].CreatedAt.After(a.psSorted[j].CreatedAt)
}

type psSortedId struct{ psSorted }

func (a psSortedId) Less(i, j int) bool { return a.psSorted[i].ID < a.psSorted[j].ID }

type psSortedImage struct{ psSorted }

func (a psSortedImage) Less(i, j int) bool { return a.psSorted[i].Image < a.psSorted[j].Image }

type psSortedNames struct{ psSorted }

func (a psSortedNames) Less(i, j int) bool { return a.psSorted[i].Names < a.psSorted[j].Names }

type psSortedPod struct{ psSorted }

func (a psSortedPod) Less(i, j int) bool { return a.psSorted[i].Pod < a.psSorted[j].Pod }

type psSortedRunningFor struct{ psSorted }

func (a psSortedRunningFor) Less(i, j int) bool {
	return a.psSorted[j].StartedAt.After(a.psSorted[i].StartedAt)
}

type psSortedStatus struct{ psSorted }

func (a psSortedStatus) Less(i, j int) bool { return a.psSorted[i].Status < a.psSorted[j].Status }

type psSortedSize struct{ psSorted }

func (a psSortedSize) Less(i, j int) bool {
	if a.psSorted[i].Size == nil || a.psSorted[j].Size == nil {
		return false
	}
	return a.psSorted[i].Size.RootFsSize < a.psSorted[j].Size.RootFsSize
}

var (
	psCommand     cliconfig.PsValues
	psDescription = "Prints out information about the containers"
	_psCommand    = cobra.Command{
		Use:   "ps",
		Args:  noSubArgs,
		Short: "List containers",
		Long:  psDescription,
		RunE: func(cmd *cobra.Command, args []string) error {
			psCommand.InputArgs = args
			psCommand.GlobalFlags = MainGlobalOpts
			return psCmd(&psCommand)
		},
		Example: `podman ps -a
  podman ps -a --format "{{.ID}}  {{.Image}}  {{.Labels}}  {{.Mounts}}"
  podman ps --size --sort names`,
	}
)

func psInit(command *cliconfig.PsValues) {
	command.SetHelpTemplate(HelpTemplate())
	command.SetUsageTemplate(UsageTemplate())
	flags := command.Flags()
	flags.BoolVarP(&command.All, "all", "a", false, "Show all the containers, default is only running containers")
	flags.StringSliceVarP(&command.Filter, "filter", "f", []string{}, "Filter output based on conditions given")
	flags.StringVar(&command.Format, "format", "", "Pretty-print containers to JSON or using a Go template")
	flags.IntVarP(&command.Last, "last", "n", -1, "Print the n last created containers (all states)")
	flags.BoolVarP(&command.Latest, "latest", "l", false, "Show the latest container created (all states)")
	flags.BoolVar(&command.Namespace, "namespace", false, "Display namespace information")
	flags.BoolVar(&command.Namespace, "ns", false, "Display namespace information")
	flags.BoolVar(&command.NoTrunct, "no-trunc", false, "Display the extended information")
	flags.BoolVarP(&command.Pod, "pod", "p", false, "Print the ID and name of the pod the containers are associated with")
	flags.BoolVarP(&command.Quiet, "quiet", "q", false, "Print the numeric IDs of the containers only")
	flags.BoolVarP(&command.Size, "size", "s", false, "Display the total file sizes")
	flags.StringVar(&command.Sort, "sort", "created", "Sort output by command, created, id, image, names, runningfor, size, or status")
	flags.BoolVar(&command.Sync, "sync", false, "Sync container state with OCI runtime")
	flags.UintVarP(&command.Watch, "watch", "w", 0, "Watch the ps output on an interval in seconds")

	markFlagHiddenForRemoteClient("latest", flags)
}

func init() {
	psCommand.Command = &_psCommand
	psInit(&psCommand)
}

func psCmd(c *cliconfig.PsValues) error {
	if os.Geteuid() != 0 {
		rootless.SetSkipStorageSetup(true)
	}
	if c.Bool("trace") {
		span, _ := opentracing.StartSpanFromContext(Ctx, "psCmd")
		defer span.Finish()
	}
	// TODO disable when single rootless userns merges
	if c.Bool("size") && os.Geteuid() != 0 {
		return errors.New("the --size option is not presently supported without root")
	}

	var watch bool

	if c.Watch > 0 {
		watch = true
	}

	if c.Watch > 0 && c.Latest {
		return errors.New("the watch and latest flags cannot be used together")
	}

	if err := checkFlagsPassed(c); err != nil {
		return errors.Wrapf(err, "error with flags passed")
	}

	runtime, err := libpodruntime.GetRuntime(&c.PodmanCommand)
	if err != nil {
		return errors.Wrapf(err, "error creating libpod runtime")
	}

	defer runtime.Shutdown(false)

	if !watch {
		if err := psDisplay(c, runtime); err != nil {
			return err
		}
	} else {
		for {
			tm.Clear()
			tm.MoveCursor(1, 1)
			tm.Flush()
			if err := psDisplay(c, runtime); err != nil {
				return err
			}
			time.Sleep(time.Duration(c.Watch) * time.Second)
			tm.Clear()
			tm.MoveCursor(1, 1)
			tm.Flush()
		}
	}
	return nil
}

func printQuiet(containers []shared.PsContainerOutput) error {
	for _, c := range containers {
		fmt.Println(c.ID)
	}
	return nil
}

// checkFlagsPassed checks if mutually exclusive flags are passed together
func checkFlagsPassed(c *cliconfig.PsValues) error {
	// latest, and last are mutually exclusive.
	if c.Last >= 0 && c.Latest {
		return errors.Errorf("last and latest are mutually exclusive")
	}
	// Quiet conflicts with size, namespace, and format with a Go template
	if c.Quiet {
		if c.Size || c.Namespace || (c.Flag("format").Changed &&
			c.Format != formats.JSONString) {
			return errors.Errorf("quiet conflicts with size, namespace, and format with go template")
		}
	}
	// Size and namespace conflict with each other
	if c.Size && c.Namespace {
		return errors.Errorf("size and namespace options conflict")
	}
	return nil
}

func generateContainerFilterFuncs(filter, filterValue string, runtime *libpod.Runtime) (func(container *libpod.Container) bool, error) {
	switch filter {
	case "id":
		return func(c *libpod.Container) bool {
			return strings.Contains(c.ID(), filterValue)
		}, nil
	case "label":
		var filterArray []string = strings.SplitN(filterValue, "=", 2)
		var filterKey string = filterArray[0]
		if len(filterArray) > 1 {
			filterValue = filterArray[1]
		} else {
			filterValue = ""
		}
		return func(c *libpod.Container) bool {
			for labelKey, labelValue := range c.Labels() {
				if labelKey == filterKey && ("" == filterValue || labelValue == filterValue) {
					return true
				}
			}
			return false
		}, nil
	case "name":
		return func(c *libpod.Container) bool {
			return strings.Contains(c.Name(), filterValue)
		}, nil
	case "exited":
		exitCode, err := strconv.ParseInt(filterValue, 10, 32)
		if err != nil {
			return nil, errors.Wrapf(err, "exited code out of range %q", filterValue)
		}
		return func(c *libpod.Container) bool {
			ec, exited, err := c.ExitCode()
			if ec == int32(exitCode) && err == nil && exited == true {
				return true
			}
			return false
		}, nil
	case "status":
		if !util.StringInSlice(filterValue, []string{"created", "running", "paused", "stopped", "exited", "unknown"}) {
			return nil, errors.Errorf("%s is not a valid status", filterValue)
		}
		return func(c *libpod.Container) bool {
			status, err := c.State()
			if err != nil {
				return false
			}
			if filterValue == "stopped" {
				filterValue = "exited"
			}
			state := status.String()
			if status == libpod.ContainerStateConfigured {
				state = "created"
			} else if status == libpod.ContainerStateStopped {
				state = "exited"
			}
			return state == filterValue
		}, nil
	case "ancestor":
		// This needs to refine to match docker
		// - ancestor=(<image-name>[:tag]|<image-id>| ⟨image@digest⟩) - containers created from an image or a descendant.
		return func(c *libpod.Container) bool {
			containerConfig := c.Config()
			if strings.Contains(containerConfig.RootfsImageID, filterValue) || strings.Contains(containerConfig.RootfsImageName, filterValue) {
				return true
			}
			return false
		}, nil
	case "before":
		ctr, err := runtime.LookupContainer(filterValue)
		if err != nil {
			return nil, errors.Errorf("unable to find container by name or id of %s", filterValue)
		}
		containerConfig := ctr.Config()
		createTime := containerConfig.CreatedTime
		return func(c *libpod.Container) bool {
			cc := c.Config()
			return createTime.After(cc.CreatedTime)
		}, nil
	case "since":
		ctr, err := runtime.LookupContainer(filterValue)
		if err != nil {
			return nil, errors.Errorf("unable to find container by name or id of %s", filterValue)
		}
		containerConfig := ctr.Config()
		createTime := containerConfig.CreatedTime
		return func(c *libpod.Container) bool {
			cc := c.Config()
			return createTime.Before(cc.CreatedTime)
		}, nil
	case "volume":
		//- volume=(<volume-name>|<mount-point-destination>)
		return func(c *libpod.Container) bool {
			containerConfig := c.Config()
			var dest string
			arr := strings.Split(filterValue, ":")
			source := arr[0]
			if len(arr) == 2 {
				dest = arr[1]
			}
			for _, mount := range containerConfig.Spec.Mounts {
				if dest != "" && (mount.Source == source && mount.Destination == dest) {
					return true
				}
				if dest == "" && mount.Source == source {
					return true
				}
			}
			return false
		}, nil
	case "health":
		return func(c *libpod.Container) bool {
			hcStatus, err := c.HealthCheckStatus()
			if err != nil {
				return false
			}
			return hcStatus == filterValue
		}, nil
	}
	return nil, errors.Errorf("%s is an invalid filter", filter)
}

// generate the accurate header based on template given
func (p *psTemplateParams) headerMap() map[string]string {
	v := reflect.Indirect(reflect.ValueOf(p))
	values := make(map[string]string)

	for i := 0; i < v.NumField(); i++ {
		key := v.Type().Field(i).Name
		value := key
		if value == "ID" {
			value = "Container" + value
		}
		values[key] = strings.ToUpper(splitCamelCase(value))
	}
	return values
}

func sortPsOutput(sortBy string, psOutput psSorted) (psSorted, error) {
	switch sortBy {
	case "id":
		sort.Sort(psSortedId{psOutput})
	case "image":
		sort.Sort(psSortedImage{psOutput})
	case "command":
		sort.Sort(psSortedCommand{psOutput})
	case "runningfor":
		sort.Sort(psSortedRunningFor{psOutput})
	case "status":
		sort.Sort(psSortedStatus{psOutput})
	case "size":
		sort.Sort(psSortedSize{psOutput})
	case "names":
		sort.Sort(psSortedNames{psOutput})
	case "created":
		sort.Sort(psSortedCreated{psOutput})
	case "pod":
		sort.Sort(psSortedPod{psOutput})
	default:
		return nil, errors.Errorf("invalid option for --sort, options are: command, created, id, image, names, runningfor, size, or status")
	}
	return psOutput, nil
}

func printFormat(format string, containers []shared.PsContainerOutput) error {
	// return immediately if no containers are present
	if len(containers) == 0 {
		return nil
	}

	// Use a tabwriter to align column format
	w := tabwriter.NewWriter(os.Stdout, 0, 0, 3, ' ', 0)

	// Make a map of the field names for the headers
	headerNames := make(map[string]string)
	v := reflect.ValueOf(containers[0])
	t := v.Type()
	for i := 0; i < t.NumField(); i++ {
		headerNames[t.Field(i).Name] = t.Field(i).Name
	}

	// Spit out the header if "table" is present in the format
	if strings.HasPrefix(format, "table") {
		hformat := strings.Replace(strings.TrimSpace(format[5:]), " ", "\t", -1)
		format = hformat
		headerTmpl, err := template.New("header").Parse(hformat)
		if err != nil {
			return err
		}
		if err := headerTmpl.Execute(w, headerNames); err != nil {
			return err
		}
		fmt.Fprintln(w, "")
	}

	// Spit out the data rows now
	dataTmpl, err := template.New("data").Parse(format)
	if err != nil {
		return err
	}

	for _, container := range containers {
		if err := dataTmpl.Execute(w, container); err != nil {
			return err
		}
		fmt.Fprintln(w, "")
	}
	// Flush the writer
	return w.Flush()
}

func dumpJSON(containers []shared.PsContainerOutput) error {
	b, err := json.MarshalIndent(containers, "", "     ")
	if err != nil {
		return err
	}
	os.Stdout.Write(b)
	return nil
}

func psDisplay(c *cliconfig.PsValues, runtime *libpod.Runtime) error {
	var (
		filterFuncs      []libpod.ContainerFilter
		outputContainers []*libpod.Container
		err              error
	)
	opts := shared.PsOptions{
		All:       c.All,
		Format:    c.Format,
		Last:      c.Last,
		Latest:    c.Latest,
		NoTrunc:   c.NoTrunct,
		Pod:       c.Pod,
		Quiet:     c.Quiet,
		Size:      c.Size,
		Namespace: c.Namespace,
		Sort:      c.Sort,
		Sync:      c.Sync,
	}

	maxWorkers := shared.Parallelize("ps")
	if c.GlobalIsSet("max-workers") {
		maxWorkers = c.GlobalFlags.MaxWorks
	}
	logrus.Debugf("Setting maximum workers to %d", maxWorkers)

	filters := c.Filter
	if len(filters) > 0 {
		for _, f := range filters {
			filterSplit := strings.SplitN(f, "=", 2)
			if len(filterSplit) < 2 {
				return errors.Errorf("filter input must be in the form of filter=value: %s is invalid", f)
			}
			generatedFunc, err := generateContainerFilterFuncs(filterSplit[0], filterSplit[1], runtime)
			if err != nil {
				return errors.Wrapf(err, "invalid filter")
			}
			filterFuncs = append(filterFuncs, generatedFunc)
		}
	}
	if !opts.Latest {
		// Get all containers
		containers, err := runtime.GetContainers(filterFuncs...)
		if err != nil {
			return err
		}

		// We only want the last few containers
		if opts.Last > 0 && opts.Last <= len(containers) {
			return errors.Errorf("--last not yet supported")
		} else {
			outputContainers = containers
		}
	} else {
		// Get just the latest container
		// Ignore filters
		latestCtr, err := runtime.GetLatestContainer()
		if err != nil {
			return err
		}

		outputContainers = []*libpod.Container{latestCtr}
	}

	pss := shared.PBatch(outputContainers, maxWorkers, opts)
	if opts.Sort != "" {
		pss, err = sortPsOutput(opts.Sort, pss)
		if err != nil {
			return err
		}
	}

	// If quiet, print only cids and return
	if opts.Quiet {
		return printQuiet(pss)
	}

	// If the user wants their own GO template format
	if opts.Format != "" {
		if opts.Format == "json" {
			return dumpJSON(pss)
		}
		return printFormat(opts.Format, pss)
	}

	// Define a tab writer with stdout as the output
	w := tabwriter.NewWriter(os.Stdout, 0, 0, 2, ' ', 0)

	// Output standard PS headers
	if !opts.Namespace {
		fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\t%s\t%s", hid, himage, hcommand, hcreated, hstatus, hports, hnames)
		// User wants pod info
		if opts.Pod {
			fmt.Fprintf(w, "\t%s", hpod)
		}
		//User wants size info
		if opts.Size {
			fmt.Fprintf(w, "\t%s", hsize)
		}
	} else {
		// Output Namespace headers
		fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s", hid, hnames, nspid, nscgroup, nsipc, nsmnt, nsnet, nspidns, nsuserns, nsuts)
	}

	// Now iterate each container and output its information
	for _, container := range pss {

		// Standard PS output
		if !opts.Namespace {
			fmt.Fprintf(w, "\n%s\t%s\t%s\t%s\t%s\t%s\t%s", container.ID, container.Image, container.Command, container.Created, container.Status, container.Ports, container.Names)
			// User wants pod info
			if opts.Pod {
				fmt.Fprintf(w, "\t%s", container.Pod)
			}
			//User wants size info
			if opts.Size {
				var size string
				if container.Size == nil {
					size = units.HumanSizeWithPrecision(0, 0)
				} else {
					size = units.HumanSizeWithPrecision(float64(container.Size.RwSize), 3) + " (virtual " + units.HumanSizeWithPrecision(float64(container.Size.RootFsSize), 3) + ")"
					fmt.Fprintf(w, "\t%s", size)
				}
			}

		} else {
			// Print namespace information
			ns := shared.GetNamespaces(container.Pid)
			fmt.Fprintf(w, "\n%s\t%s\t%d\t%s\t%s\t%s\t%s\t%s\t%s\t%s", container.ID, container.Names, container.Pid, ns.Cgroup, ns.IPC, ns.MNT, ns.NET, ns.PIDNS, ns.User, ns.UTS)
		}

	}
	fmt.Fprint(w, "\n")
	return w.Flush()
}