package local

import (
	"encoding/base64"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/http"
	"strconv"
	"strings"

	"github.com/Sirupsen/logrus"
	"github.com/docker/distribution/digest"
	"github.com/docker/docker/api/server/httputils"
	"github.com/docker/docker/api/types"
	"github.com/docker/docker/builder"
	"github.com/docker/docker/builder/dockerfile"
	"github.com/docker/docker/daemon/daemonbuilder"
	derr "github.com/docker/docker/errors"
	"github.com/docker/docker/pkg/archive"
	"github.com/docker/docker/pkg/chrootarchive"
	"github.com/docker/docker/pkg/ioutils"
	"github.com/docker/docker/pkg/progress"
	"github.com/docker/docker/pkg/streamformatter"
	"github.com/docker/docker/pkg/ulimit"
	"github.com/docker/docker/reference"
	"github.com/docker/docker/runconfig"
	"github.com/docker/docker/utils"
	"golang.org/x/net/context"
)

func (s *router) postCommit(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	if err := httputils.ParseForm(r); err != nil {
		return err
	}

	if err := httputils.CheckForJSON(r); err != nil {
		return err
	}

	cname := r.Form.Get("container")

	pause := httputils.BoolValue(r, "pause")
	version := httputils.VersionFromContext(ctx)
	if r.FormValue("pause") == "" && version.GreaterThanOrEqualTo("1.13") {
		pause = true
	}

	c, _, err := runconfig.DecodeContainerConfig(r.Body)
	if err != nil && err != io.EOF { //Do not fail if body is empty.
		return err
	}
	if c == nil {
		c = &runconfig.Config{}
	}

	if !s.daemon.Exists(cname) {
		return derr.ErrorCodeNoSuchContainer.WithArgs(cname)
	}

	newConfig, err := dockerfile.BuildFromConfig(c, r.Form["changes"])
	if err != nil {
		return err
	}

	commitCfg := &types.ContainerCommitConfig{
		Pause:        pause,
		Repo:         r.Form.Get("repo"),
		Tag:          r.Form.Get("tag"),
		Author:       r.Form.Get("author"),
		Comment:      r.Form.Get("comment"),
		Config:       newConfig,
		MergeConfigs: true,
	}

	imgID, err := s.daemon.Commit(cname, commitCfg)
	if err != nil {
		return err
	}

	return httputils.WriteJSON(w, http.StatusCreated, &types.ContainerCommitResponse{
		ID: string(imgID),
	})
}

// Creates an image from Pull or from Import
func (s *router) postImagesCreate(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	if err := httputils.ParseForm(r); err != nil {
		return err
	}

	var (
		image   = r.Form.Get("fromImage")
		repo    = r.Form.Get("repo")
		tag     = r.Form.Get("tag")
		message = r.Form.Get("message")
	)
	authEncoded := r.Header.Get("X-Registry-Auth")
	authConfig := &types.AuthConfig{}
	if authEncoded != "" {
		authJSON := base64.NewDecoder(base64.URLEncoding, strings.NewReader(authEncoded))
		if err := json.NewDecoder(authJSON).Decode(authConfig); err != nil {
			// for a pull it is not an error if no auth was given
			// to increase compatibility with the existing api it is defaulting to be empty
			authConfig = &types.AuthConfig{}
		}
	}

	var (
		err    error
		output = ioutils.NewWriteFlusher(w)
	)
	defer output.Close()

	w.Header().Set("Content-Type", "application/json")

	if image != "" { //pull
		// Special case: "pull -a" may send an image name with a
		// trailing :. This is ugly, but let's not break API
		// compatibility.
		image = strings.TrimSuffix(image, ":")

		var ref reference.Named
		ref, err = reference.ParseNamed(image)
		if err == nil {
			if tag != "" {
				// The "tag" could actually be a digest.
				var dgst digest.Digest
				dgst, err = digest.ParseDigest(tag)
				if err == nil {
					ref, err = reference.WithDigest(ref, dgst)
				} else {
					ref, err = reference.WithTag(ref, tag)
				}
			}
			if err == nil {
				metaHeaders := map[string][]string{}
				for k, v := range r.Header {
					if strings.HasPrefix(k, "X-Meta-") {
						metaHeaders[k] = v
					}
				}

				err = s.daemon.PullImage(ref, metaHeaders, authConfig, output)
			}
		}
	} else { //import
		var newRef reference.Named
		if repo != "" {
			var err error
			newRef, err = reference.ParseNamed(repo)
			if err != nil {
				return err
			}

			switch newRef.(type) {
			case reference.Canonical:
				return errors.New("cannot import digest reference")
			}

			if tag != "" {
				newRef, err = reference.WithTag(newRef, tag)
				if err != nil {
					return err
				}
			}
		}

		src := r.Form.Get("fromSrc")

		// 'err' MUST NOT be defined within this block, we need any error
		// generated from the download to be available to the output
		// stream processing below
		var newConfig *runconfig.Config
		newConfig, err = dockerfile.BuildFromConfig(&runconfig.Config{}, r.Form["changes"])
		if err != nil {
			return err
		}

		err = s.daemon.ImportImage(src, newRef, message, r.Body, output, newConfig)
	}
	if err != nil {
		if !output.Flushed() {
			return err
		}
		sf := streamformatter.NewJSONStreamFormatter()
		output.Write(sf.FormatError(err))
	}

	return nil
}

func (s *router) postImagesPush(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	metaHeaders := map[string][]string{}
	for k, v := range r.Header {
		if strings.HasPrefix(k, "X-Meta-") {
			metaHeaders[k] = v
		}
	}
	if err := httputils.ParseForm(r); err != nil {
		return err
	}
	authConfig := &types.AuthConfig{}

	authEncoded := r.Header.Get("X-Registry-Auth")
	if authEncoded != "" {
		// the new format is to handle the authConfig as a header
		authJSON := base64.NewDecoder(base64.URLEncoding, strings.NewReader(authEncoded))
		if err := json.NewDecoder(authJSON).Decode(authConfig); err != nil {
			// to increase compatibility to existing api it is defaulting to be empty
			authConfig = &types.AuthConfig{}
		}
	} else {
		// the old format is supported for compatibility if there was no authConfig header
		if err := json.NewDecoder(r.Body).Decode(authConfig); err != nil {
			return fmt.Errorf("Bad parameters and missing X-Registry-Auth: %v", err)
		}
	}

	ref, err := reference.ParseNamed(vars["name"])
	if err != nil {
		return err
	}
	tag := r.Form.Get("tag")
	if tag != "" {
		// Push by digest is not supported, so only tags are supported.
		ref, err = reference.WithTag(ref, tag)
		if err != nil {
			return err
		}
	}

	output := ioutils.NewWriteFlusher(w)
	defer output.Close()

	w.Header().Set("Content-Type", "application/json")

	if err := s.daemon.PushImage(ref, metaHeaders, authConfig, output); err != nil {
		if !output.Flushed() {
			return err
		}
		sf := streamformatter.NewJSONStreamFormatter()
		output.Write(sf.FormatError(err))
	}
	return nil
}

func (s *router) getImagesGet(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	if err := httputils.ParseForm(r); err != nil {
		return err
	}

	w.Header().Set("Content-Type", "application/x-tar")

	output := ioutils.NewWriteFlusher(w)
	defer output.Close()
	var names []string
	if name, ok := vars["name"]; ok {
		names = []string{name}
	} else {
		names = r.Form["names"]
	}

	if err := s.daemon.ExportImage(names, output); err != nil {
		if !output.Flushed() {
			return err
		}
		sf := streamformatter.NewJSONStreamFormatter()
		output.Write(sf.FormatError(err))
	}
	return nil
}

func (s *router) postImagesLoad(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	return s.daemon.LoadImage(r.Body, w)
}

func (s *router) deleteImages(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	if err := httputils.ParseForm(r); err != nil {
		return err
	}

	name := vars["name"]

	if strings.TrimSpace(name) == "" {
		return fmt.Errorf("image name cannot be blank")
	}

	force := httputils.BoolValue(r, "force")
	prune := !httputils.BoolValue(r, "noprune")

	list, err := s.daemon.ImageDelete(name, force, prune)
	if err != nil {
		return err
	}

	return httputils.WriteJSON(w, http.StatusOK, list)
}

func (s *router) getImagesByName(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	imageInspect, err := s.daemon.LookupImage(vars["name"])
	if err != nil {
		return err
	}

	return httputils.WriteJSON(w, http.StatusOK, imageInspect)
}

func (s *router) postBuild(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	var (
		authConfigs        = map[string]types.AuthConfig{}
		authConfigsEncoded = r.Header.Get("X-Registry-Config")
		buildConfig        = &dockerfile.Config{}
	)

	if authConfigsEncoded != "" {
		authConfigsJSON := base64.NewDecoder(base64.URLEncoding, strings.NewReader(authConfigsEncoded))
		if err := json.NewDecoder(authConfigsJSON).Decode(&authConfigs); err != nil {
			// for a pull it is not an error if no auth was given
			// to increase compatibility with the existing api it is defaulting
			// to be empty.
		}
	}

	w.Header().Set("Content-Type", "application/json")

	version := httputils.VersionFromContext(ctx)
	output := ioutils.NewWriteFlusher(w)
	defer output.Close()
	sf := streamformatter.NewJSONStreamFormatter()
	errf := func(err error) error {
		// Do not write the error in the http output if it's still empty.
		// This prevents from writing a 200(OK) when there is an internal error.
		if !output.Flushed() {
			return err
		}
		_, err = w.Write(sf.FormatError(errors.New(utils.GetErrorMessage(err))))
		if err != nil {
			logrus.Warnf("could not write error response: %v", err)
		}
		return nil
	}

	if httputils.BoolValue(r, "forcerm") && version.GreaterThanOrEqualTo("1.12") {
		buildConfig.Remove = true
	} else if r.FormValue("rm") == "" && version.GreaterThanOrEqualTo("1.12") {
		buildConfig.Remove = true
	} else {
		buildConfig.Remove = httputils.BoolValue(r, "rm")
	}
	if httputils.BoolValue(r, "pull") && version.GreaterThanOrEqualTo("1.16") {
		buildConfig.Pull = true
	}

	repoAndTags, err := sanitizeRepoAndTags(r.Form["t"])
	if err != nil {
		return errf(err)
	}

	buildConfig.DockerfileName = r.FormValue("dockerfile")
	buildConfig.Verbose = !httputils.BoolValue(r, "q")
	buildConfig.UseCache = !httputils.BoolValue(r, "nocache")
	buildConfig.ForceRemove = httputils.BoolValue(r, "forcerm")
	buildConfig.MemorySwap = httputils.Int64ValueOrZero(r, "memswap")
	buildConfig.Memory = httputils.Int64ValueOrZero(r, "memory")
	buildConfig.CPUShares = httputils.Int64ValueOrZero(r, "cpushares")
	buildConfig.CPUPeriod = httputils.Int64ValueOrZero(r, "cpuperiod")
	buildConfig.CPUQuota = httputils.Int64ValueOrZero(r, "cpuquota")
	buildConfig.CPUSetCpus = r.FormValue("cpusetcpus")
	buildConfig.CPUSetMems = r.FormValue("cpusetmems")
	buildConfig.CgroupParent = r.FormValue("cgroupparent")

	if r.Form.Get("shmsize") != "" {
		shmSize, err := strconv.ParseInt(r.Form.Get("shmsize"), 10, 64)
		if err != nil {
			return errf(err)
		}
		buildConfig.ShmSize = &shmSize
	}

	if i := runconfig.IsolationLevel(r.FormValue("isolation")); i != "" {
		if !runconfig.IsolationLevel.IsValid(i) {
			return errf(fmt.Errorf("Unsupported isolation: %q", i))
		}
		buildConfig.Isolation = i
	}

	var buildUlimits = []*ulimit.Ulimit{}
	ulimitsJSON := r.FormValue("ulimits")
	if ulimitsJSON != "" {
		if err := json.NewDecoder(strings.NewReader(ulimitsJSON)).Decode(&buildUlimits); err != nil {
			return errf(err)
		}
		buildConfig.Ulimits = buildUlimits
	}

	var buildArgs = map[string]string{}
	buildArgsJSON := r.FormValue("buildargs")
	if buildArgsJSON != "" {
		if err := json.NewDecoder(strings.NewReader(buildArgsJSON)).Decode(&buildArgs); err != nil {
			return errf(err)
		}
		buildConfig.BuildArgs = buildArgs
	}

	remoteURL := r.FormValue("remote")

	// Currently, only used if context is from a remote url.
	// Look at code in DetectContextFromRemoteURL for more information.
	createProgressReader := func(in io.ReadCloser) io.ReadCloser {
		progressOutput := sf.NewProgressOutput(output, true)
		return progress.NewProgressReader(in, progressOutput, r.ContentLength, "Downloading context", remoteURL)
	}

	var (
		context        builder.ModifiableContext
		dockerfileName string
	)
	context, dockerfileName, err = daemonbuilder.DetectContextFromRemoteURL(r.Body, remoteURL, createProgressReader)
	if err != nil {
		return errf(err)
	}
	defer func() {
		if err := context.Close(); err != nil {
			logrus.Debugf("[BUILDER] failed to remove temporary context: %v", err)
		}
	}()

	uidMaps, gidMaps := s.daemon.GetUIDGIDMaps()
	defaultArchiver := &archive.Archiver{
		Untar:   chrootarchive.Untar,
		UIDMaps: uidMaps,
		GIDMaps: gidMaps,
	}
	docker := &daemonbuilder.Docker{
		Daemon:      s.daemon,
		OutOld:      output,
		AuthConfigs: authConfigs,
		Archiver:    defaultArchiver,
	}

	b, err := dockerfile.NewBuilder(buildConfig, docker, builder.DockerIgnoreContext{ModifiableContext: context}, nil)
	if err != nil {
		return errf(err)
	}
	b.Stdout = &streamformatter.StdoutFormatter{Writer: output, StreamFormatter: sf}
	b.Stderr = &streamformatter.StderrFormatter{Writer: output, StreamFormatter: sf}

	if closeNotifier, ok := w.(http.CloseNotifier); ok {
		finished := make(chan struct{})
		defer close(finished)
		go func() {
			select {
			case <-finished:
			case <-closeNotifier.CloseNotify():
				logrus.Infof("Client disconnected, cancelling job: build")
				b.Cancel()
			}
		}()
	}

	if len(dockerfileName) > 0 {
		b.DockerfileName = dockerfileName
	}

	imgID, err := b.Build()
	if err != nil {
		return errf(err)
	}

	for _, rt := range repoAndTags {
		if err := s.daemon.TagImage(rt, imgID); err != nil {
			return errf(err)
		}
	}

	return nil
}

// sanitizeRepoAndTags parses the raw "t" parameter received from the client
// to a slice of repoAndTag.
// It also validates each repoName and tag.
func sanitizeRepoAndTags(names []string) ([]reference.Named, error) {
	var (
		repoAndTags []reference.Named
		// This map is used for deduplicating the "-t" parameter.
		uniqNames = make(map[string]struct{})
	)
	for _, repo := range names {
		if repo == "" {
			continue
		}

		ref, err := reference.ParseNamed(repo)
		if err != nil {
			return nil, err
		}

		if _, isCanonical := ref.(reference.Canonical); isCanonical {
			return nil, errors.New("build tag cannot contain a digest")
		}

		if _, isTagged := ref.(reference.NamedTagged); !isTagged {
			ref, err = reference.WithTag(ref, reference.DefaultTag)
		}

		nameWithTag := ref.String()

		if _, exists := uniqNames[nameWithTag]; !exists {
			uniqNames[nameWithTag] = struct{}{}
			repoAndTags = append(repoAndTags, ref)
		}
	}
	return repoAndTags, nil
}

func (s *router) getImagesJSON(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	if err := httputils.ParseForm(r); err != nil {
		return err
	}

	// FIXME: The filter parameter could just be a match filter
	images, err := s.daemon.Images(r.Form.Get("filters"), r.Form.Get("filter"), httputils.BoolValue(r, "all"))
	if err != nil {
		return err
	}

	return httputils.WriteJSON(w, http.StatusOK, images)
}

func (s *router) getImagesHistory(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	name := vars["name"]
	history, err := s.daemon.ImageHistory(name)
	if err != nil {
		return err
	}

	return httputils.WriteJSON(w, http.StatusOK, history)
}

func (s *router) postImagesTag(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	if err := httputils.ParseForm(r); err != nil {
		return err
	}
	repo := r.Form.Get("repo")
	tag := r.Form.Get("tag")
	newTag, err := reference.WithName(repo)
	if err != nil {
		return err
	}
	if tag != "" {
		if newTag, err = reference.WithTag(newTag, tag); err != nil {
			return err
		}
	}
	if err := s.daemon.TagImage(newTag, vars["name"]); err != nil {
		return err
	}
	w.WriteHeader(http.StatusCreated)
	return nil
}

func (s *router) getImagesSearch(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
	if err := httputils.ParseForm(r); err != nil {
		return err
	}
	var (
		config      *types.AuthConfig
		authEncoded = r.Header.Get("X-Registry-Auth")
		headers     = map[string][]string{}
	)

	if authEncoded != "" {
		authJSON := base64.NewDecoder(base64.URLEncoding, strings.NewReader(authEncoded))
		if err := json.NewDecoder(authJSON).Decode(&config); err != nil {
			// for a search it is not an error if no auth was given
			// to increase compatibility with the existing api it is defaulting to be empty
			config = &types.AuthConfig{}
		}
	}
	for k, v := range r.Header {
		if strings.HasPrefix(k, "X-Meta-") {
			headers[k] = v
		}
	}
	query, err := s.daemon.SearchRegistryForImages(r.Form.Get("term"), config, headers)
	if err != nil {
		return err
	}
	return httputils.WriteJSON(w, http.StatusOK, query.Results)
}