#!/usr/bin/env python
# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2014 IBM Corporation
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


# 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, ?: mimic 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 readline
import select
import shlex
import sys
import termios
import tty

exitcode = 0
consoleonly = False
consolename = ""
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
import confluent.common.client as client

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

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

statedata = {}


def updatestatus(stateinfo):
    status = consolename
    if 'clientcount' in stateinfo:
        statedata['clientcount'] = stateinfo['clientcount']
    if 'connectstate' in stateinfo:
        statedata['connectstate'] = stateinfo['connectstate']
    info = []
    if ('connectstate' in statedata and
            statedata['connectstate'] != 'connected'):
        info.append(statedata['connectstate'])
    if 'clientcount' in statedata and statedata['clientcount'] != 1:
        info.append('clients: %d' % statedata['clientcount'])
    if info:
        status += ' [' + ','.join(info) + ']'
    sys.stdout.write('\x1b]0;console: %s\x07' % status)
    sys.stdout.flush()


def prompt():
    sys.stdout.write('\x1b]0;confetty: %s\x07' % target)
    try:
        return raw_input(target + ' -> ')
    except KeyboardInterrupt:
        print ""
        return ""
    except EOFError:  # ctrl-d
        print("exit")
        return "exit"
#    sys.stdout.write(target + ' -> ')
#    sys.stdout.flush()
#    username = raw_input("Name: ")

valid_commands = [
    'start',
    'cd',
    'show',
    'set',
    'unset',
    'create',
    'remove',
    'rm',
    'delete',
]

candidates = None
session = None


def completer(text, state):
    try:
        return rcompleter(text, state)
    except:
        import traceback
        traceback.print_exc()


def rcompleter(text, state):
    global candidates
    global valid_commands
    cline = readline.get_line_buffer()
    if len(text):
        cline = cline[:-len(text)]
    args = shlex.split(cline, posix=True)
    currpos = len(args)
    if currpos and cline[-1] == ' ':
        lastarg = ''
        currpos += 1
    elif currpos:
        lastarg = args[-1]
    else:
        lastarg = ''
    if currpos <= 1:
        foundcount = 0
        for cmd in valid_commands:
            if cmd.startswith(text):
                if foundcount == state:
                    return cmd
                else:
                    foundcount += 1
        candidates = None
        return None
    cmd = args[0]
    if candidates is None:
        candidates = []
        targpath = fullpath_target(lastarg)
        for res in session.read(targpath):
            if 'item' in res:  # a link relation
                if type(res['item']) == dict:
                    candidates.append(res['item']["href"])
                else:
                    for item in res['item']:
                        candidates.append(item["href"])
    foundcount = 0
    for elem in candidates:
        if cmd == 'cd' and elem[-1] != '/':
            continue
        if elem.startswith(text):
            if foundcount == state:
                return elem
            else:
                foundcount += 1
    candidates = None
    return None


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


currchildren = None


def do_command(command, server):
    global exitcode
    global target
    global currconsole
    global currchildren
    exitcode = 0
    argv = parse_command(command)
    if len(argv) == 0:
        return
    argv[0] = argv[0].lower()
    if argv[0] == 'exit':
        sys.exit(0)
    elif argv[0] == 'cd':
        otarget = target
        if len(argv) > 1:
            target = fullpath_target(argv[1], forcepath=True)
        else:  # cd by itself, go 'home'
            target = '/'
        for res in session.read(target, server):
            if 'errorcode' in res:
                exitcode = res['errorcode']
            if 'error' in res:
                sys.stderr.write(target + ': ' + res['error'] + '\n')
                target = otarget
    elif argv[0] in ('cat', 'show', 'ls', 'dir'):
        if len(argv) > 1:
            targpath = fullpath_target(argv[1])
        else:
            targpath = target
        for res in session.read(targpath):
            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
                if 'error' in res:
                    sys.stderr.write(res['error'] + '\n')
                if 'errorcode' in res:
                    exitcode = res['errorcode']
                    continue
                for key in res.iterkeys():
                    notes = []
                    if res[key] is None:
                        attrstr = '%s=""' % key
                    elif type(res[key]) == list:
                        attrstr = '%s=["%s"]' % (key, '","'.join(res[key]))
                    elif 'value' in res[key] and res[key]['value'] is not None:
                        attrstr = '%s="%s"' % (key, res[key]['value'])
                    elif 'value' in res[key] and res[key]['value'] is None:
                        attrstr = '%s=""' % key
                    else:
                        if 'isset' in res[key] and res[key]['isset']:
                            attrstr = '%s="********"' % key
                        else:
                            attrstr = '%s=""' % key
                    if res[key] is not None and 'inheritedfrom' in res[key]:
                        notes.append(
                            'Inherited from %s' % res[key]['inheritedfrom'])
                    if res[key] is not None and 'expression' in res[key]:
                        notes.append(
                            ('Derived from expression "%s"' %
                             res[key]['expression']))
                    notestr = '(' + ', '.join(notes) + ')'
                    output = '{0:<40} {1:>39}'.format(attrstr, notestr)
                    print(output)
    elif argv[0] == 'start':
        targpath = fullpath_target(argv[1])
        nodename = targpath.split('/')[-3]
        currconsole = targpath
        tlvdata.send(
            session.connection, {'operation': 'start', 'path': targpath})
        status = tlvdata.recv(session.connection)
        if 'error' in status:
            if 'errorcode' in status:
                exitcode = status['errorcode']
            sys.stderr.write('Error: ' + status['error'] + '\n')
            return
        print '[console session started]'
        startconsole(nodename)
        return
    elif argv[0] == 'set':
        setvalues(argv[1:])
    elif argv[0] == 'create':
        createresource(argv[1:])
    elif argv[0] in ('rm', 'delete', 'remove'):
        delresource(argv[1])
    elif argv[0] in ('unset', 'clear'):
        clearvalues(argv[1], argv[2:])
    else:
        sys.stderr.write("%s: command not found...\n" % argv[0])


def createresource(args):
    resname = args[0]
    attribs = args[1:]
    keydata = parameterize_attribs(attribs)
    if keydata is None:
        return
    targpath = fullpath_target(resname)
    collection, _, resname = targpath.rpartition('/')
    keydata['name'] = resname
    makecall(session.create, (collection, keydata))


def makecall(callout, args):
    global exitcode
    for response in callout(*args):
        if 'error' in response:
            if 'errorcode' in response:
                exitcode = response['errorcode']
            sys.stderr.write('Error: ' + response['error'] + '\n')


def clearvalues(resource, attribs):
    global exitcode
    targpath = fullpath_target(resource)
    keydata = {}
    for attrib in attribs:
        keydata[attrib] = None
    for res in session.update(targpath, keydata):
        if 'error' in res:
            if 'errorcode' in res:
                exitcode = res['errorcode']
            sys.stderr.write('Error: ' + res['error'] + '\n')


def delresource(resname):
    resname = fullpath_target(resname)
    makecall(session.delete, (resname,))


def setvalues(attribs):
    global exitcode
    if '=' in attribs[0]:  # going straight to attribute
        resource = attribs[0][:attribs[0].index("=")]
        if '/' in resource:
            lastslash = resource.rindex('/')
            attribs[0] = attribs[0][lastslash + 1:]
    else:  # an actual resource
        resource = attribs[0]
        attribs = attribs[1:]
    keydata = parameterize_attribs(attribs)
    if not keydata:
        return
    targpath = fullpath_target(resource)
    for res in session.update(targpath, keydata):
        if 'error' in res:
            if 'errorcode' in res:
                exitcode = res['errorcode']
            sys.stderr.write('Error: ' + res['error'] + '\n')


def parameterize_attribs(attribs):
    keydata = {}
    for attrib in attribs:
        if '=' not in attrib:
            sys.stderr.write("Invalid syntax %s\n" % attrib)
            return None
        key = attrib[:attrib.index("=")]
        value = attrib[attrib.index("=") + 1:]
        if key == 'groups':
            value = value.split(',')
        keydata[key] = value
    return keydata


def fullpath_target(currpath, forcepath=False):
    global target
    if currpath == '':
        return target
    pathcomponents = currpath.split("/")
    if pathcomponents[-1] == "":  # preserve path
        forcepath = True
    if pathcomponents[0] == "":  # absolute path
        ntarget = currpath
    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 and (len(targparts) == 0 or targparts[-1] != ""):
            targparts.append('')
        ntarget = '/'.join(targparts)
    if forcepath and (len(ntarget) == 0 or ntarget[-1] != '/'):
        ntarget += '/'
    return ntarget


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


def quitconfetty(code=0, fullexit=False):
    global inconsole
    global currconsole
    currfl = fcntl.fcntl(sys.stdin.fileno(), fcntl.F_GETFL)
    fcntl.fcntl(sys.stdin.fileno(), fcntl.F_SETFL, currfl ^ os.O_NONBLOCK)
    termios.tcsetattr(sys.stdin.fileno(), termios.TCSANOW, oldtcattr)
    if fullexit:
        sys.exit(code)
    else:
        tlvdata.send(session.connection, {'operation': 'stop',
                                          'path': currconsole})
        inconsole = False


def conserver_command(filehandle, command):
    # x - conserver has that as 'show baud', I am inclined to replace that with
    #     'request exclusive'
    # b - conserver has that as 'broadcast message', I'm tempted to use that
    #     for break
    # r - replay
    # p - replay (this is the one I've always used)
    # f - force attach read/write
    # a - attach read/write
    # s - spy mode
    # l[n] - send a particular break, tempted to do l0 for compatibility
    # o - reopen tty, this should mean reconnect console
    # d - down a console... never used this...
    # L - toggle logging
    # w - who is on console
    while not command:
        ready, _, _ = select.select((filehandle,), (), (), 1)
        if ready:
            command += filehandle.read()
    if command[0] == '.':
        print("disconnect]\r")
        quitconfetty(fullexit=consoleonly)
    if command[0] == 'b':
        tlvdata.send(session.connection, {'operation': 'break',
                                          'path': currconsole})
        print("break sent]\r")
    elif command[0] == '?':
        print("help]\r")
        print(".    disconnect\r")
        print("b    break\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(currinput, filehandle):
    while conserversequence.startswith(currinput):
        if currinput.startswith(conserversequence):  # We have full sequence
            sys.stdout.write("[")
            sys.stdout.flush()
            return conserver_command(
                filehandle, currinput[len(conserversequence):])
        ready, _, _ = select.select((filehandle,), (), (), 3)
        if not ready:  # 3 seconds of no typing
            break
        currinput += filehandle.read()
    return currinput


parser = optparse.OptionParser()
parser.add_option("-s", "--server", dest="netserver",
                  help="Confluent instance to connect to",
                  metavar="SERVER:PORT")
opts, shellargs = parser.parse_args()
if opts.netserver:  # going over a TLS network
    session = client.Command(opts.server)
else:
    session = client.Command()

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

while not session.authenticated:
    username = raw_input("Name: ")
    readline.clear_history()
    passphrase = getpass.getpass("Passphrase: ")
    session.authenticate(username, passphrase)
# 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()

readline.parse_and_bind("tab: complete")
readline.parse_and_bind("set bell-style none")
readline.set_completer(completer)
doexit = False
inconsole = False
pendingcommand = ""
if len(shellargs) == 1:  # a node name, go straight to trying to console
    consoleonly = True
    do_command("start /nodes/%s/console/session" % shellargs[0], netserver)
while not doexit:
    if inconsole:
        rdylist, _, _ = select.select(
            (sys.stdin, session.connection), (), (), 60)
        for fh in rdylist:
            if fh == session.connection:
                # this only should get called in the
                # case of a console session
                # each command should slurp up all relevant
                # recv potential
                #fh.read()
                try:
                    data = tlvdata.recv(fh)
                except Exception:
                    data = None
                if type(data) == dict:
                    updatestatus(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:
                myinput = fh.read()
                myinput = check_escape_seq(myinput, fh)
                if myinput:
                    tlvdata.send(session.connection, myinput)
    else:
        currcommand = prompt()
        do_command(currcommand, netserver)
quitconfetty(fullexit=True)