#!/usr/bin/env python

# ultimately, this should provide an interactive cli for navigating confluent
# tree and doing console with a socket.  <ESC>]0;<string><BELL> can be used to
# present info such as whether it is in a console or other mode and, if in
# console, how many other connections are live and looking
# this means 'wcons' simply needs to make a terminal run and we'll take care of
# the title while providing more info
# this also means the socket interface needs to have ways to convey more
# interesting pieces of data (like concurrent connection count)
# socket will probably switch to a TLV scheme:
# 32 bit TL, 8 bits of type code and 24 bit size
# type codes:
# 0: string data
# 1: json data
# 24 bit size allows the peer to avoid having to do any particular parsing to
# understand message boundaries (which is a significant burden on the xCAT
# protocol)

# When in a console client mode, will recognize two escape sequences by
# default:
# Ctrl-E, c, ?: mimick conserver behavior
# ctrl-]: go to interactive prompt (telnet escape, but not telnet prompt)
# esc-( would interfere with normal esc use too much
# ~ I will not use for now...

import fcntl
import getpass
import optparse
import os
import select
import shlex
import socket
import ssl
import sys
import termios
import tty

consoleonly = False
target = "/"
path = os.path.dirname(os.path.realpath(__file__))
path = os.path.realpath(os.path.join(path, '..'))
sys.path.append(path)

import confluent.common.tlvdata as tlvdata

SO_PASSCRED = 16
conserversequence = '\x05c' # ctrl-e, c

oldtcattr = termios.tcgetattr(sys.stdin.fileno())
server = None

def prompt():
    sys.stdout.write(target + ' -> ')
    sys.stdout.flush()

def parseservervalue(serverstring):
    if serverstring.find(']:') != -1:
        server, port = serverstring[1:].split(']:')
    elif serverstring[0] == '[':
        server = serverstring[1:-1]
        port = 4001
    elif -1 != opts.server.find(':'):
        server, port = opts.server.split(":")
    else:
        server = serverstring
        port = 4001
    return (server, port)


def parse_command(command):
    args = shlex.split(command, posix=True)
    return args
    

currchildren = None

def send_request(operation, path, server):
    tlvdata.send_tlvdata(server, {'operation': operation, 'path': path})
    result = tlvdata.recv_tlvdata(server)
    while '_requestdone' not in result:
        yield result
        result = tlvdata.recv_tlvdata(server)

def do_command(command, server):
    global target
    global currconsole
    global currchildren
    if command == "":  # result of ctrl-d
        command = "exit\n"
        print("exit")
    command = command[:-1]
    command = command.lower()
    argv = parse_command(command)
    if len(argv) == 0:
        prompt()
        return
    if argv[0] == "exit":
        server.close()
        sys.exit(0)
    if argv[0] == "cd":
        otarget = target
        target = fullpath_target(argv[1], forcepath=True)
        for res in send_request('retrieve', target, server):
            if 'error' in res:
                print target + ': ' + res['error']
                target = otarget
    if argv[0] in ('show', 'ls'):
        if len(argv) > 1:
            targpath = fullpath_target(argv[1])
        else:
            targpath = target
        for res in send_request('retrieve', targpath, server):
            if 'item' in res:  # a link relation
                if type(res['item']) == dict:
                    print res['item']["href"]
                else:
                    for item in res['item']:
                        print item["href"]
            else:  # generic attributes to list
                for key in res.iterkeys():
                    if 'value' in res[key]:
                        print "%s=%s" % (key, res[key]['value'])
                    else:
                        if 'isset' in res[key] and res[key]['isset']:
                            print "%s=********" % key
                        else:
                            print "%s=" % key
    if argv[0] == 'start':
        targpath = fullpath_target(argv[1])
        currconsole = targpath
        tlvdata.send_tlvdata(server, {'operation': 'start', 'path': targpath})
        status = tlvdata.recv_tlvdata(server)
        if 'error' in status:
            print 'Error: ' + status['error']
            return
        print '[console session started]'
        startconsole()
        return
    prompt()


def fullpath_target(path, forcepath=False):
    global target
    pathcomponents = path.split("/")
    if pathcomponents[0] == "":  # absolute path
        ntarget = path
    else:
        targparts = target.split("/")[:-1]
        for component in pathcomponents:
            if component in ('.',''):  # ignore these
                continue
            elif component == '..':
                if len(targparts) > 0:
                    del targparts[-1]
            else:
                targparts.append(component)
        if forcepath:
            targparts.append('')
        ntarget = '/'.join(targparts)
    if forcepath and (len(ntarget) == 0 or ntarget[-1] != '/'):
        ntarget += '/'
    return ntarget

def startconsole():
    global inconsole
    tty.setraw(sys.stdin.fileno())
    fcntl.fcntl(sys.stdin.fileno(), fcntl.F_SETFL, os.O_NONBLOCK)
    inconsole = True

def exit(code=0):
    global consoleonly
    global inconsole
    global currconsole
    termios.tcsetattr(sys.stdin.fileno(), termios.TCSANOW, oldtcattr)
    if consoleonly:
        server.shutdown(socket.SHUT_RDWR)
        server.close()
        sys.exit(code)
    else:
        tlvdata.send_tlvdata(server, {'operation': 'stop', 'path': currconsole})
        inconsole = False
        prompt()

def conserver_command(fh, command):
    while not command:
        ready, _, _ = select.select((fh,), (), (), 1)
        if ready:
            command += fh.read()
    if command[0] == '.':
        print("disconnect]\r")
        exit()
    elif command[0] == '?':
        print("help]\r")
        print(".    disconnect\r")
        print("<cr> abort command\r")
    elif command[0] == '\x0d':
        print("ignored]\r")
    else: #not a command at all..
        print("unknown -- use '?']\r")


def check_escape_seq(input, fh):
    while conserversequence.startswith(input):
        if input.startswith(conserversequence):  # We have full sequence
            sys.stdout.write("[")
            sys.stdout.flush()
            return conserver_command(fh, input[len(conserversequence):])
        ready, _, _ = select.select((fh,), (), (), 3)
        if not ready:  # 3 seconds of no typing
            break
        input += fh.read()
    return input


def connect_unix_server(sockpath):
    server = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
    server.setsockopt(socket.SOL_SOCKET, SO_PASSCRED, 1)
    server.connect(sockpath)
    return server


def connect_tls_server(serverstring):
    host, port = parseservervalue(serverstring)
    for res in socket.getaddrinfo(host, port, socket.AF_UNSPEC,
            socket.SOCK_STREAM):
        af, socktype, proto, cononname, sa = res
        try:
            server = socket.socket(af, socktype, proto)
        except:
            server = None
            continue
        try:
            server.settimeout(5)
            server.connect(sa)
        except:
            server.close()
            server = None
            continue
        break
    if server is None:
        sys.stderr.write("Failed to connect to %s\n" % serverstring)
        sys.exit(1)
    secserver = ssl.wrap_socket(server)
    return secserver

parser = optparse.OptionParser()
parser.add_option("-s", "--server", dest="server",
                  help="TLS server to connect to", metavar="SERVER:PORT")
parser.add_option("-u", "--unixsocket", dest="unixsock",
                  help="TLS server to connect to", metavar="UNIXDOMAINSOCKET")
opts, args =  parser.parse_args()
if opts.server:  # going over a TLS network
    server = connect_tls_server(opts.server)
elif opts.unixsock:
    server = connect_unix_server(opts.unixsock)
elif os.path.exists("/var/run/confluent/api.sock"):
    server = connect_unix_server("/var/run/confluent/api.sock")

#Next stop, reading and writing from whichever of stdin and server goes first.
#see pyghmi code for solconnect.py

banner = tlvdata.recv_tlvdata(server)
authinfo = tlvdata.recv_tlvdata(server)
while authinfo['authpassed'] != 1:
    username = raw_input("Name: ")
    passphrase = getpass.getpass("Passphrase: ")
    tlvdata.send_tlvdata(server,
                         {'username': username, 'passphrase': passphrase})
    authinfo = tlvdata.recv_tlvdata(server)
# clear on start can help with readable of TUI, but it
# can be annoying, so for now don't do it.
# sys.stdout.write('\x1b[H\x1b[J')
# sys.stdout.flush()

doexit = False
inconsole = False
pendingcommand = ""
if len(args) == 1:  # a node name, go straight to trying to console
    consoleonly = True
    do_command("start /node/%s/console/session" % args[0], server)
else:
    prompt()
while not doexit:
    rdylist, _, _ = select.select((sys.stdin, server), (), (), 60)
    for fh in rdylist:
        if fh == server:
            # this only should get called in the
            # case of a console session
            # each command should slurp up all relevant
            # recv_tlvdata potential
            #fh.read()
            try:
                data = tlvdata.recv_tlvdata(fh)
            except Exception:
                data = None
            if type(data) == dict:
                print repr(data)
                continue
            if data is not None:
                sys.stdout.write(data)
                sys.stdout.flush()
            else:
                doexit = True
                sys.stdout.write("\r\n[remote disconnected]\r\n")
                break
        else:
            if inconsole:
                input = fh.read()
                input = check_escape_seq(input, fh)
                if input:
                    tlvdata.send_tlvdata(server, input)
            else:
                command = fh.readline()
                do_command(command, server)
exit()