// Verifies that the 'message' is included in the signature and that it
// is correct.
// Message is your own hash, and reply contains the inclusion proof + signature
// on the aggregated message
func VerifySignature(suite abstract.Suite, reply *StampSignature, public abstract.Point, message []byte) bool {
	// Check if aggregate public key is correct
	if !public.Equal(reply.AggPublic) {
		dbg.Lvl1("Aggregate-public-key check: FAILED (maybe you have an outdated config file of the tree)")
		return false
	}
	// First check if the challenge is ok
	if err := VerifyChallenge(suite, reply); err != nil {
		dbg.Lvl1("Challenge-check: FAILED (", err, ")")
		return false
	}
	dbg.Lvl2("Challenge-check: OK")

	// Incorporate the timestamp in the message since the verification process
	// is done by reconstructing the challenge
	var b bytes.Buffer
	if err := binary.Write(&b, binary.LittleEndian, reply.Timestamp); err != nil {
		dbg.Lvl1("Error marshaling the timestamp for signature verification")
		return false
	}
	msg := append(b.Bytes(), []byte(reply.MerkleRoot)...)
	if err := VerifySchnorr(suite, msg, public, reply.Challenge, reply.Response); err != nil {
		dbg.Lvl1("Signature-check: FAILED (", err, ")")
		return false
	}
	dbg.Lvl2("Signature-check: OK")

	// finally check the proof
	if !proof.CheckProof(suite.Hash, reply.MerkleRoot, hashid.HashId(message), reply.Prf) {
		dbg.Lvl2("Inclusion-check: FAILED")
		return false
	}
	dbg.Lvl2("Inclusion-check: OK")
	return true
}

// NewDataFilter returns a new data filter initialized with the rights values
// taken out from the run config. If absent, will take defaults values.
// Keys expected are:
// discard_measurementname = perc => will take the lower and upper percentile =
// perc
// discard_measurementname = lower,upper => will take different percentiles
func NewDataFilter(config map[string]string) DataFilter {
	df := DataFilter{
		percentiles: make(map[string]float64),
	}
	reg, err := regexp.Compile("filter_(\\w+)")
	if err != nil {
		dbg.Lvl1("DataFilter: Error compiling regexp:", err)
		return df
	}
	// analyse the each entry
	for k, v := range config {
		if measure := reg.FindString(k); measure == "" {
			continue
		} else {
			// this value must be filtered by how many ?
			perc, err := strconv.ParseFloat(v, 64)
			if err != nil {
				dbg.Lvl1("DataFilter: Cannot parse value for filter measure:", measure)
				continue
			}
			measure = strings.Replace(measure, "filter_", "", -1)
			df.percentiles[measure] = perc
		}
	}
	dbg.Lvl3("Filtering:", df.percentiles)
	return df
}

func RunServer(flags *app.Flags, conf *app.ConfigColl) {
	hostname := flags.Hostname
	if hostname == conf.Hosts[0] {
		dbg.Lvlf3("Tree is %+v", conf.Tree)
	}
	dbg.Lvl3(hostname, "Starting to run")

	app.RunFlags.StartedUp(len(conf.Hosts))
	peer := conode.NewPeer(hostname, conf.ConfigConode)

	if app.RunFlags.AmRoot {
		for {
			setupRound := sign.NewRoundSetup(peer.Node)
			peer.StartAnnouncementWithWait(setupRound, 5*time.Second)
			counted := <-setupRound.Counted
			dbg.Lvl1("Number of peers counted:", counted)
			if counted == len(conf.Hosts) {
				dbg.Lvl1("All hosts replied")
				break
			}
			time.Sleep(time.Second)
		}
	}

	RegisterRoundMeasure(peer.Node.LastRound())
	peer.LoopRounds(RoundMeasureType, conf.Rounds)
	dbg.Lvlf3("Done - flags are %+v", app.RunFlags)
	monitor.End()
}

// scaleServers will take the right percentage of server to contact to stamp
// request. If percentage is 0, only contact the leader (if the client is on the
// same physical machine than the leader/root).
func scaleServers(flags *app.Flags, conf *app.ConfigColl, servers []string) []string {
	if len(servers) == 0 || conf.StampRatio > 1 {
		dbg.Lvl1("Client wont change the servers percentage ")
		return servers
	}
	if conf.StampRatio == -1 {
		// take only the root if  we are a "root client" also
		if flags.AmRoot {
			dbg.Lvl1("Client will only contact root")
			return []string{servers[0]}
		} else {
			// others client dont do nothing
			dbg.Lvl3("Client wont contact anyone")
			return []string{}
		}
	}
	// else take the right perc
	i := int(math.Ceil(conf.StampRatio * float64(len(servers))))
	fn := dbg.Lvl3
	if flags.AmRoot {
		fn = dbg.Lvl1
	}
	fn("Client will contact", i, "/", len(servers), "servers")
	return servers[0:i]
}

func ExampleLongFunctions() {
	dbg.Lvl1("Before")
	thisIsAVeryLongFunctionNameThatWillOverflow()
	dbg.Lvl1("After")

	// Output:
	// 1: (           dbg_test.ExampleLongFunctions:   0) - Before
	// 1: (dbg_test.thisIsAVeryLongFunctionNameThatWillOverflow:   0) - Overflow
	// 1: (                       dbg_test.ExampleLongFunctions:   0) - After
}

// verifyHost will anaylze the systempacket information and verify the signature
// It will return a ACK properly initialized with the right codes in it.
func verifyHost(pubKeyFile string) (net.Conn, Ack) {
	//  get the right public key
	pub, host, err := cliutils.ReadPubKey(suite, pubKeyFile)
	if err != nil {
		dbg.Fatal("Could not read the public key from the file:", err)
	}
	dbg.Lvl1("Public key file read")

	// Then get a connection
	conn, err := net.Dial("tcp", host)
	if err != nil {
		dbg.Fatal("Error when getting the connection to the host:", err)
	}

	dbg.Lvl1("Verifier connected to the host. Validation in progress...")
	// Get the system packet message
	var sys SystemPacket
	if err = suite.Read(conn, &sys); err != nil {
		dbg.Fatal("Error when reading the system packet message from host:", err)
	}
	// Get the signature length first
	var length int
	if err := suite.Read(conn, &length); err != nil {
		dbg.Fatal("Could not read length of the signature ...")
	}
	// Get the signature
	sig := make([]byte, length)
	if err := suite.Read(conn, &sig); err != nil {
		dbg.Fatal("Error reading the signature:", err)
	}

	// First, encode the sys packet
	var b bytes.Buffer
	if err := suite.Write(&b, sys); err != nil {
		dbg.Fatal("Error when encoding the syspacket to be verified:", err)
	}
	X := make([]abstract.Point, 1)
	X[0] = pub

	// Verify signature
	var ack Ack
	ack.Type = TYPE_SYS
	ack.Code = SYS_EXIT
	if _, err := anon.Verify(suite, b.Bytes(), anon.Set(X), nil, sig); err != nil {
		// Wrong signature
		ack.Code = SYS_WRONG_SIG
		dbg.Lvl1("WARNING: signature provided is wrong.")
	} else {
		// verfiy SystemPacket itself
		ack.Code = SYS_OK
		dbg.Lvl1("Host's signature verified and system seems healty. OK")
	}

	return conn, ack
}

func wait_for_blocks() {

	server := "localhost:2011"
	suite = app.GetSuite("25519")

	dbg.Lvl2("Connecting to", server)
	conn := coconet.NewTCPConn(server)
	err := conn.Connect()
	if err != nil {
		dbg.Fatal("Error when getting the connection to the host:", err)
	}
	dbg.Lvl1("Connected to ", server)
	for i := 0; i < 1000; i++ {
		time.Sleep(1 * time.Second)
		msg := &BitCoSi.BitCoSiMessage{
			Type:  BitCoSi.BlockRequestType,
			ReqNo: 0,
		}

		err = conn.PutData(msg)
		if err != nil {
			dbg.Fatal("Couldn't send hash-message to server: ", err)
		}
		dbg.Lvl1("Sent signature request")
		// Wait for the signed message

		tsm := new(BitCoSi.BitCoSiMessage)
		tsm.Brep = &BitCoSi.BlockReply{}
		tsm.Brep.SuiteStr = suite.String()
		err = conn.GetData(tsm)
		if err != nil {
			dbg.Fatal("Error while receiving signature:", err)
		}
		//dbg.Lvlf1("Got signature response %+v", tsm.Brep)

		T := new(BitCoSi.TrBlock)
		T.Block = tsm.Brep.Block
		T.Print()
		dbg.Lvlf1("Response %v ", tsm.Brep.Response)
	}
	// Asking to close the connection
	err = conn.PutData(&BitCoSi.BitCoSiMessage{
		ReqNo: 1,
		Type:  BitCoSi.BitCoSiClose,
	})

	conn.Close()

}

// The core of the file: read any input from the connection and outputs it into
// the server connection
func proxyConnection(conn net.Conn, done chan bool) {
	dec := json.NewDecoder(conn)
	nerr := 0
	for {
		m := Measure{}
		// Receive data
		if err := dec.Decode(&m); err != nil {
			if err == io.EOF {
				break
			}
			dbg.Lvl1("Error receiving data from", conn.RemoteAddr().String(), ":", err)
			nerr += 1
			if nerr > 1 {
				dbg.Lvl1("Too many errors from", conn.RemoteAddr().String(), ": Abort connection")
				break
			}
		}
		dbg.Lvl3("Proxy received", m)

		// Implement our own ready-count, so it doesn't have to go through the
		// main monitor which might be far away.
		switch m.Name {
		case "ready":
			atomic.AddInt64(&readyCount, 1)
		case "ready_count":
			m.Ready = int(readyCount)
			err := json.NewEncoder(conn).Encode(m)
			if err != nil {
				dbg.Lvl2("Couldn't send ready-result back to client")
				break
			}
		default:
			// Proxy data - add who is sending, as we only have one channel
			// to the server
			m.Sender = conn.RemoteAddr().String()
			if err := serverEnc.Encode(m); err != nil {
				dbg.Lvl2("Error proxying data :", err)
				break
			}
			if m.Name == "end" {
				// the end
				dbg.Lvl2("Proxy detected end of measurement. Closing connection.")
				break
			}
		}
	}
	conn.Close()
	done <- true
}

func (d *Localhost) Start(args ...string) error {
	os.Chdir(d.RunDir)
	dbg.Lvl4("Localhost: chdir into", d.RunDir)
	ex := d.RunDir + "/" + d.App
	dbg.Lvl4("Localhost: in Start() => hosts", d.Hosts)
	d.running = true
	dbg.Lvl1("Starting", len(d.Hosts), "applications of", ex)
	for index, host := range d.Hosts {
		dbg.Lvl3("Starting", index, "=", host)
		amroot := fmt.Sprintf("-amroot=%s", strconv.FormatBool(index == 0))
		cmdArgs := []string{"-hostname", host, "-mode", "server", "-logger",
			"localhost:" + monitor.SinkPort, amroot}
		cmdArgs = append(args, cmdArgs...)
		dbg.Lvl3("CmdArgs are", cmdArgs)
		cmd := exec.Command(ex, cmdArgs...)
		cmd.Stdout = os.Stdout
		cmd.Stderr = os.Stderr
		go func(i int, h string) {
			dbg.Lvl3("Localhost: will start host", host)
			d.wg_run.Add(1)
			err := cmd.Run()
			if err != nil {
				dbg.Lvl3("Error running localhost", h, ":", err)
			}
			d.wg_run.Done()
			dbg.Lvl3("host (index", i, ")", h, "done")
		}(index, host)
	}
	return nil
}

// Reads in the platform that we want to use and prepares for the tests
func main() {
	flag.Parse()
	deployP = platform.NewPlatform(platform_dst)
	if deployP == nil {
		dbg.Fatal("Platform not recognized.", platform_dst)
	}
	dbg.Lvl1("Deploying to", platform_dst)

	simulations := flag.Args()
	if len(simulations) == 0 {
		dbg.Fatal("Please give a simulation to run")
	}

	for _, simulation := range simulations {
		runconfigs := platform.ReadRunFile(deployP, simulation)

		if len(runconfigs) == 0 {
			dbg.Fatal("No tests found in", simulation)
		}
		deployP.Configure()

		if clean {
			deployP.Deploy(runconfigs[0])
			deployP.Cleanup()
		} else {
			logname := strings.Replace(filepath.Base(simulation), ".toml", "", 1)
			RunTests(logname, runconfigs)
		}
	}
}

// readHostFile will read the host file
// HOSTNAME PUBLICKEY
// for each line. and returns the whole set and any errror if any are found.
func readHostFile(file string) ([]string, []string, error) {
	// open it up
	hostFile, err := os.Open(file)
	if err != nil {
		return nil, nil, err
	}

	// Then read it up
	hosts := make([]string, 0)
	pubs := make([]string, 0)
	scanner := bufio.NewScanner(hostFile)
	ln := 0
	for scanner.Scan() {
		line := scanner.Text()
		ln += 1
		spl := strings.Split(line, " ")
		if len(spl) != 2 {
			return nil, nil, errors.New(fmt.Sprintf("Hostfile misformatted at line %s", ln))
		}
		// add it HOSTS -> PUBLIC KEY
		h, err := cliutils.VerifyPort(spl[0], conode.DefaultPort)
		if err != nil {
			dbg.Fatal("Error reading address in host file:", spl[0], err)
		}
		hosts = append(hosts, h)
		pubs = append(pubs, spl[1])
	}
	dbg.Lvl1("Read the hosts files:", ln, "entries")
	return hosts, pubs, nil
}

// Scanner for a file contatining singatures
func SigScanner(filename string) ([]string, error) {
	var blocks []string
	head := "-----BEGIN PGP SIGNATURE-----"
	dbg.Lvl3("Reading file", filename)

	file, err := os.Open(filename)
	defer file.Close()
	if err != nil {
		dbg.Lvl1("Couldn't open file", file, err)
		return nil, err
	}

	scanner := bufio.NewScanner(file)
	var block []string
	for scanner.Scan() {
		text := scanner.Text()
		dbg.Lvl3("Decoding", text)
		// end of the first part
		if text == head {
			dbg.Lvl3("Found header")
			if len(block) > 0 {
				blocks = append(blocks, strings.Join(block, "\n"))
				block = make([]string, 0)
			}
		}
		block = append(block, text)
	}
	blocks = append(blocks, strings.Join(block, "\n"))
	return blocks, nil
}

// This file handles the creation a of cothority tree.
// Basically, it takes a list of files generated by the "key" command by each
// hosts and turn that into a full tree with the hostname and public key in each
// node.
// BuildTree takes a file formatted like this :
// host pubKey
// host2 pubKey
// ... ...
// For the moment it takes a branching factor on how to make the tree
// and the name of the file where to write the config
// It writes the tree + any other configs to output using toml format
// with the app/config_conode.go struct
func Build(hostFile string, bf int, configFile string) {

	// First, read the list of host and public keys
	hosts, pubs, err := readHostFile(hostFile)
	if err != nil {
		dbg.Fatal("Error reading the host file:", err)
	}

	// Then construct the tree
	tree := constructTree(hosts, pubs, bf)
	// then constrcut the aggregated public key K0
	k0 := aggregateKeys(pubs)
	var b bytes.Buffer
	err = cliutils.WritePub64(suite, &b, k0)
	if err != nil {
		dbg.Fatal("Could not aggregate public keys in base64")
	}

	// Then write the config
	conf := app.ConfigConode{
		Suite:     suiteStr,
		Tree:      tree,
		Hosts:     hosts,
		AggPubKey: b.String(),
	}

	app.WriteTomlConfig(conf, configFile)
	dbg.Lvl1("Written config file with tree to", configFile)
}

// Helper functions that will return the suite used during the process from a string name
func GetSuite(suite string) abstract.Suite {
	s, ok := suites.All()[suite]
	if !ok {
		dbg.Lvl1("Suites available:", suites.All())
		dbg.Fatal("Didn't find suite", suite)
	}
	return s
}

func verify(metadata *CommitEntry, beSigned string) {
	defer wg.Done()
	var err error
	metadata.decision, err = ApprovalCheck(metadata.policy, metadata.signatures, beSigned)
	if err != nil {
		dbg.Lvl1("Problem with verifying approval of developers")
	}
}

func (round *RoundMeasure) Response(in []*sign.SigningMessage, out *sign.SigningMessage) error {
	err := round.RoundCosi.Response(in, out)
	if round.IsRoot {
		round.measure.Measure()
		dbg.Lvl1("Round", round.RoundNbr-round.firstRound+1,
			"finished - took", round.measure.WallTime)
	}
	return err
}

// Send message to client given by name
func (round *RoundStamperListener) PutToClient(name string, data coconet.BinaryMarshaler) {
	err := round.Clients[name].PutData(data)
	if err == coconet.ErrClosed {
		round.Clients[name].Close()
		return
	}
	if err != nil && err != coconet.ErrNotEstablished {
		dbg.Lvl1("%p error putting to client: %v", round, err)
	}
}

// Scanner for a file containing commit id
func CommitScanner(filename string) (string, error) {
	dbg.Lvl3("Reading file", filename)

	file, err := os.Open(filename)
	defer file.Close()
	if err != nil {
		dbg.Lvl1("Couldn't open file", file, err)
		return "", err
	}

	comid := make([]byte, 40)
	_, err = file.Read(comid)
	if err != nil {
		dbg.Lvl1("Couldn't read from file", filename, err)
		return "", err
	}

	return string(comid), err
}

// SImply adds all the public keys we give to it
func aggregateKeys(pubs []string) abstract.Point {
	k0 := suite.Point().Null()
	for i, ki := range pubs {
		// convert from string to public key
		kip, _ := cliutils.ReadPub64(suite, strings.NewReader(ki))
		k0 = k0.Add(k0, kip)
		dbg.Lvl2("Public key n#", i, ":", kip)
	}
	dbg.Lvl1("Aggregated public key:", k0)
	return k0
}

// Takes a 'file' to hash and being stamped at the 'server'. The output of the
// signing will be written to 'file'.sig
func StampFile(file, server string) {
	// Create the hash of the file and send it over the net
	myHash := hashFile(file)

	stamper, err := conode.NewStamp("config.toml")
	if err != nil {
		dbg.Fatal("Couldn't setup stamper:", err)
	}
	tsm, err := stamper.GetStamp(myHash, server)
	if err != nil {
		dbg.Fatal("Stamper didn't succeed:", err)
	}

	if err := tsm.Srep.Save(file + sigExtension); err != nil {
		dbg.Fatal("Could not write signature file:", err)
	}
	dbg.Lvl1("Signature file", file+".sig", "written.")

	dbg.Lvl1("Stamp OK - signature file", file+".sig", "written.")
}