package main

import (
	"code.google.com/p/weed-fs/go/glog"
	"code.google.com/p/weed-fs/go/operation"
	"code.google.com/p/weed-fs/go/replication"
	"code.google.com/p/weed-fs/go/storage"
	"github.com/gorilla/mux"
	"math/rand"
	"mime"
	"net/http"
	"os"
	"path/filepath"
	"runtime"
	"strconv"
	"strings"
	"time"
)

func init() {
	cmdVolume.Run = runVolume // break init cycle
	cmdVolume.IsDebug = cmdVolume.Flag.Bool("debug", false, "enable debug mode")
}

var cmdVolume = &Command{
	UsageLine: "volume -port=8080 -dir=/tmp -max=5 -ip=server_name -mserver=localhost:9333",
	Short:     "start a volume server",
	Long: `start a volume server to provide storage spaces

  `,
}

var (
	vport                 = cmdVolume.Flag.Int("port", 8080, "http listen port")
	volumeFolders         = cmdVolume.Flag.String("dir", os.TempDir(), "directories to store data files. dir[,dir]...")
	maxVolumeCounts       = cmdVolume.Flag.String("max", "7", "maximum numbers of volumes, count[,count]...")
	ip                    = cmdVolume.Flag.String("ip", "localhost", "ip or server name")
	publicUrl             = cmdVolume.Flag.String("publicUrl", "", "Publicly accessible <ip|server_name>:<port>")
	masterNode            = cmdVolume.Flag.String("mserver", "localhost:9333", "master server location")
	vpulse                = cmdVolume.Flag.Int("pulseSeconds", 5, "number of seconds between heartbeats, must be smaller than the master's setting")
	vReadTimeout          = cmdVolume.Flag.Int("readTimeout", 3, "connection read timeout in seconds. Increase this if uploading large files.")
	vMaxCpu               = cmdVolume.Flag.Int("maxCpu", 0, "maximum number of CPUs. 0 means all available CPUs")
	dataCenter            = cmdVolume.Flag.String("dataCenter", "", "current volume server's data center name")
	rack                  = cmdVolume.Flag.String("rack", "", "current volume server's rack name")
	volumeWhiteListOption = cmdVolume.Flag.String("whiteList", "", "comma separated Ip addresses having write permission. No limit if empty.")

	store           *storage.Store
	volumeWhiteList []string
)

var fileNameEscaper = strings.NewReplacer("\\", "\\\\", "\"", "\\\"")

func statusHandler(w http.ResponseWriter, r *http.Request) {
	m := make(map[string]interface{})
	m["Version"] = VERSION
	m["Volumes"] = store.Status()
	writeJsonQuiet(w, r, m)
}
func assignVolumeHandler(w http.ResponseWriter, r *http.Request) {
	err := store.AddVolume(r.FormValue("volume"), r.FormValue("collection"), r.FormValue("replicationType"))
	if err == nil {
		writeJsonQuiet(w, r, map[string]string{"error": ""})
	} else {
		writeJsonQuiet(w, r, map[string]string{"error": err.Error()})
	}
	debug("assign volume =", r.FormValue("volume"), ", collection =", r.FormValue("collection"), ", replicationType =", r.FormValue("replicationType"), ", error =", err)
}
func vacuumVolumeCheckHandler(w http.ResponseWriter, r *http.Request) {
	err, ret := store.CheckCompactVolume(r.FormValue("volume"), r.FormValue("garbageThreshold"))
	if err == nil {
		writeJsonQuiet(w, r, map[string]interface{}{"error": "", "result": ret})
	} else {
		writeJsonQuiet(w, r, map[string]interface{}{"error": err.Error(), "result": false})
	}
	debug("checked compacting volume =", r.FormValue("volume"), "garbageThreshold =", r.FormValue("garbageThreshold"), "vacuum =", ret)
}
func vacuumVolumeCompactHandler(w http.ResponseWriter, r *http.Request) {
	err := store.CompactVolume(r.FormValue("volume"))
	if err == nil {
		writeJsonQuiet(w, r, map[string]string{"error": ""})
	} else {
		writeJsonQuiet(w, r, map[string]string{"error": err.Error()})
	}
	debug("compacted volume =", r.FormValue("volume"), ", error =", err)
}
func vacuumVolumeCommitHandler(w http.ResponseWriter, r *http.Request) {
	err := store.CommitCompactVolume(r.FormValue("volume"))
	if err == nil {
		writeJsonQuiet(w, r, map[string]interface{}{"error": ""})
	} else {
		writeJsonQuiet(w, r, map[string]string{"error": err.Error()})
	}
	debug("commit compact volume =", r.FormValue("volume"), ", error =", err)
}
func freezeVolumeHandler(w http.ResponseWriter, r *http.Request) {
	//TODO: notify master that this volume will be read-only
	err := store.FreezeVolume(r.FormValue("volume"))
	if err == nil {
		writeJsonQuiet(w, r, map[string]interface{}{"error": ""})
	} else {
		writeJsonQuiet(w, r, map[string]string{"error": err.Error()})
	}
	debug("freeze volume =", r.FormValue("volume"), ", error =", err)
}
func submitFromVolumeServerHandler(w http.ResponseWriter, r *http.Request) {
	submitForClientHandler(w, r, *masterNode)
}
func storeHandler(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case "GET":
		GetOrHeadHandler(w, r, true)
	case "HEAD":
		GetOrHeadHandler(w, r, false)
	case "DELETE":
		secure(volumeWhiteList, DeleteHandler)(w, r)
	case "PUT":
		secure(volumeWhiteList, PostHandler)(w, r)
	case "POST":
		secure(volumeWhiteList, PostHandler)(w, r)
	}
}
func GetOrHeadHandler(w http.ResponseWriter, r *http.Request, isGetMethod bool) {
	n := new(storage.Needle)
	vid, fid, filename, ext, _ := parseURLPath(r.URL.Path)
	volumeId, err := storage.NewVolumeId(vid)
	if err != nil {
		debug("parsing error:", err, r.URL.Path)
		return
	}
	n.ParsePath(fid)

	debug("volume", volumeId, "reading", n)
	if !store.HasVolume(volumeId) {
		lookupResult, err := operation.Lookup(*masterNode, volumeId)
		debug("volume", volumeId, "found on", lookupResult, "error", err)
		if err == nil {
			http.Redirect(w, r, "http://"+lookupResult.Locations[0].PublicUrl+r.URL.Path, http.StatusMovedPermanently)
		} else {
			debug("lookup error:", err, r.URL.Path)
			w.WriteHeader(http.StatusNotFound)
		}
		return
	}
	cookie := n.Cookie
	count, e := store.Read(volumeId, n)
	debug("read bytes", count, "error", e)
	if e != nil || count <= 0 {
		debug("read error:", e, r.URL.Path)
		w.WriteHeader(http.StatusNotFound)
		return
	}
	if n.Cookie != cookie {
		glog.V(0).Infoln("request with unmaching cookie from ", r.RemoteAddr, "agent", r.UserAgent())
		w.WriteHeader(http.StatusNotFound)
		return
	}
	if n.LastModified != 0 {
		w.Header().Set("Last-Modified", time.Unix(int64(n.LastModified), 0).UTC().Format(http.TimeFormat))
		if r.Header.Get("If-Modified-Since") != "" {
			if t, parseError := time.Parse(http.TimeFormat, r.Header.Get("If-Modified-Since")); parseError == nil {
				if t.Unix() >= int64(n.LastModified) {
					w.WriteHeader(http.StatusNotModified)
					return
				}
			}
		}
	}
	if n.NameSize > 0 && filename == "" {
		filename = string(n.Name)
		dotIndex := strings.LastIndex(filename, ".")
		if dotIndex > 0 {
			ext = filename[dotIndex:]
		}
	}
	mtype := ""
	if ext != "" {
		mtype = mime.TypeByExtension(ext)
	}
	if n.MimeSize > 0 {
		mtype = string(n.Mime)
	}
	if mtype != "" {
		w.Header().Set("Content-Type", mtype)
	}
	if filename != "" {
		w.Header().Set("Content-Disposition", "filename="+fileNameEscaper.Replace(filename))
	}
	if ext != ".gz" {
		if n.IsGzipped() {
			if strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
				w.Header().Set("Content-Encoding", "gzip")
			} else {
				if n.Data, err = storage.UnGzipData(n.Data); err != nil {
					debug("lookup error:", err, r.URL.Path)
				}
			}
		}
	}
	w.Header().Set("Content-Length", strconv.Itoa(len(n.Data)))
	if isGetMethod {
		if _, e = w.Write(n.Data); e != nil {
			debug("response write error:", e)
		}
	}
}
func PostHandler(w http.ResponseWriter, r *http.Request) {
	m := make(map[string]interface{})
	if e := r.ParseForm(); e != nil {
		debug("form parse error:", e)
		writeJsonError(w, r, e)
		return
	}
	vid, _, _, _, _ := parseURLPath(r.URL.Path)
	volumeId, ve := storage.NewVolumeId(vid)
	if ve != nil {
		debug("NewVolumeId error:", ve)
		writeJsonError(w, r, ve)
		return
	}
	needle, ne := storage.NewNeedle(r)
	if ne != nil {
		writeJsonError(w, r, ne)
		return
	}
	ret, errorStatus := replication.ReplicatedWrite(*masterNode, store, volumeId, needle, r)
	if errorStatus == "" {
		w.WriteHeader(http.StatusCreated)
	} else {
		w.WriteHeader(http.StatusInternalServerError)
		m["error"] = errorStatus
	}
	m["size"] = ret
	writeJsonQuiet(w, r, m)
}
func DeleteHandler(w http.ResponseWriter, r *http.Request) {
	n := new(storage.Needle)
	vid, fid, _, _, _ := parseURLPath(r.URL.Path)
	volumeId, _ := storage.NewVolumeId(vid)
	n.ParsePath(fid)

	debug("deleting", n)

	cookie := n.Cookie
	count, ok := store.Read(volumeId, n)

	if ok != nil {
		m := make(map[string]uint32)
		m["size"] = 0
		writeJsonQuiet(w, r, m)
		return
	}

	if n.Cookie != cookie {
		glog.V(0).Infoln("delete with unmaching cookie from ", r.RemoteAddr, "agent", r.UserAgent())
		return
	}

	n.Size = 0
	ret := replication.ReplicatedDelete(*masterNode, store, volumeId, n, r)

	if ret != 0 {
		w.WriteHeader(http.StatusAccepted)
	} else {
		w.WriteHeader(http.StatusInternalServerError)
	}

	m := make(map[string]uint32)
	m["size"] = uint32(count)
	writeJsonQuiet(w, r, m)
}

func parseURLPath(path string) (vid, fid, filename, ext string, isVolumeIdOnly bool) {
	switch strings.Count(path, "/") {
	case 3:
		parts := strings.Split(path, "/")
		vid, fid, filename = parts[1], parts[2], parts[3]
		ext = filepath.Ext(filename)
	case 2:
		parts := strings.Split(path, "/")
		vid, fid = parts[1], parts[2]
		dotIndex := strings.LastIndex(fid, ".")
		if dotIndex > 0 {
			ext = fid[dotIndex:]
			fid = fid[0:dotIndex]
		}
	default:
		sepIndex := strings.LastIndex(path, "/")
		commaIndex := strings.LastIndex(path[sepIndex:], ",")
		if commaIndex <= 0 {
			vid, isVolumeIdOnly = path[sepIndex+1:], true
			return
		}
		dotIndex := strings.LastIndex(path[sepIndex:], ".")
		vid = path[sepIndex+1 : commaIndex]
		fid = path[commaIndex+1:]
		ext = ""
		if dotIndex > 0 {
			fid = path[commaIndex+1 : dotIndex]
			ext = path[dotIndex:]
		}
	}
	return
}

func runVolume(cmd *Command, args []string) bool {
	if *vMaxCpu < 1 {
		*vMaxCpu = runtime.NumCPU()
	}
	runtime.GOMAXPROCS(*vMaxCpu)
	folders := strings.Split(*volumeFolders, ",")
	maxCountStrings := strings.Split(*maxVolumeCounts, ",")
	maxCounts := make([]int, 0)
	for _, maxString := range maxCountStrings {
		if max, e := strconv.Atoi(maxString); e == nil {
			maxCounts = append(maxCounts, max)
		} else {
			glog.Fatalf("The max specified in -max not a valid number %s", max)
		}
	}
	if len(folders) != len(maxCounts) {
		glog.Fatalf("%d directories by -dir, but only %d max is set by -max", len(folders), len(maxCounts))
	}
	for _, folder := range folders {
		fileInfo, err := os.Stat(folder)
		if err != nil {
			glog.Fatalf("No Existing Folder:%s", folder)
		}
		if !fileInfo.IsDir() {
			glog.Fatalf("Volume Folder should not be a file:%s", folder)
		}
		perm := fileInfo.Mode().Perm()
		glog.V(0).Infoln("Volume Folder", folder)
		glog.V(0).Infoln("Permission:", perm)
	}

	if *publicUrl == "" {
		*publicUrl = *ip + ":" + strconv.Itoa(*vport)
	}
	if *volumeWhiteListOption != "" {
		volumeWhiteList = strings.Split(*volumeWhiteListOption, ",")
	}

	store = storage.NewStore(*vport, *ip, *publicUrl, folders, maxCounts)
	defer store.Close()
	r := mux.NewRouter()
	r.HandleFunc("/submit", secure(volumeWhiteList, submitFromVolumeServerHandler))
	r.HandleFunc("/status", secure(volumeWhiteList, statusHandler))
	r.HandleFunc("/admin/assign_volume", secure(volumeWhiteList, assignVolumeHandler))
	r.HandleFunc("/admin/vacuum_volume_check", secure(volumeWhiteList, vacuumVolumeCheckHandler))
	r.HandleFunc("/admin/vacuum_volume_compact", secure(volumeWhiteList, vacuumVolumeCompactHandler))
	r.HandleFunc("/admin/vacuum_volume_commit", secure(volumeWhiteList, vacuumVolumeCommitHandler))
	r.HandleFunc("/admin/freeze_volume", secure(volumeWhiteList, freezeVolumeHandler))
	r.HandleFunc("/", storeHandler)

	go func() {
		connected := true
		store.SetMaster(*masterNode)
		store.SetDataCenter(*dataCenter)
		store.SetRack(*rack)
		for {
			err := store.Join()
			if err == nil {
				if !connected {
					connected = true
					glog.V(0).Infoln("Reconnected with master")
				}
			} else {
				if connected {
					connected = false
				}
			}
			time.Sleep(time.Duration(float32(*vpulse*1e3)*(1+rand.Float32())) * time.Millisecond)
		}
	}()
	glog.V(0).Infoln("store joined at", *masterNode)

	glog.V(0).Infoln("Start Weed volume server", VERSION, "at http://"+*ip+":"+strconv.Itoa(*vport))
	srv := &http.Server{
		Addr:        ":" + strconv.Itoa(*vport),
		Handler:     r,
		ReadTimeout: (time.Duration(*vReadTimeout) * time.Second),
	}
	e := srv.ListenAndServe()
	if e != nil {
		glog.Fatalf("Fail to start:%s", e.Error())
	}
	return true
}