#============================================================================
# Copyright (c) Microsoft Corporation. All rights reserved. See license.txt for license information.
#============================================================================
import os
import protocol
import socket
import struct
import sys
import traceback
import ctypes

DO_TRACE = True
DO_VERBOSE_TRACE  = False
ScriptsDir = "/opt/microsoft/omsconfig/Scripts"
VarDir = "/var/opt/microsoft/omsconfig"

def trace (text):
    if DO_TRACE:
        sys.stdout.write (text + '\n')

def verbose_trace (text):
    if DO_VERBOSE_TRACE:
        trace (text)

        
def read_uchar (fd):
    verbose_trace ('<read_uchar>')
    buf = fd.recv (1)
    if len (buf) < 1:
        return None
    val = struct.unpack ('@B',buf)[0]
    verbose_trace ('  val: '+str(int (val)))
    verbose_trace ('</read_uchar>')
    return val


def read_request (fd):
    verbose_trace ('<read_request>')
    op_type = read_uchar (fd)
    if op_type == None:
        return None
    verbose_trace ('  op_type: ' + str(op_type))
    op_name = protocol.read_string (fd)
    verbose_trace ('  op_name: "'+ op_name +'"')
    d = protocol.read_values (fd)
    verbose_trace ('</read_request>')
    return (op_type, op_name, d)

    
def write_int (fd, val):
    verbose_trace ('<write_int>')
    verbose_trace ('  val: '+str(val))
    buf = struct.pack ('@i', val)
    fd.send (buf)
    verbose_trace ('</write_int>')


def write_success (fd, args = None):
    trace ('<write_success>')
    write_int (fd, 0)
    if args is not None:
        protocol.write_values (fd, args)
    trace ('</write_success>')


def write_failed (s, fail_code, text=''):
    trace ('<write_failed>')
    write_int (s, fail_code)
    protocol.write_string (s, text)
    trace ('</write_failed>')


def translate_input (d):
    """ This method is a convenience for a protocol chnage and should be
        removed when the handlers are updated."""
    verbose_trace ('<translate_input>')
    oldStyleD = dict ()
    if sys.version > '2.9':
        for key, value in d.items():
            if type(key) != str:
                key=str(key)
            if hasattr(value,'value') and hasattr(value.value,'value') :
                oldStyleD[key] = value.value.value
            else :
                oldStyleD[key] = value.value
    else:
        for key, value in d.iteritems():
            if type(key) != str:
                key=str(key)
            if hasattr(value,'value') and hasattr(value.value,'value') :
                oldStyleD[key] = value.value.value
            else:
                oldStyleD[key] = value.value
    verbose_trace ('</translate_input>')
    return oldStyleD


def callMOF (req):
    oldStyleDict = translate_input (req[2])
    trace ('MOF=' + repr ((req[0], req[1], oldStyleDict)))
    op = ('Test','Set','Get','Inventory')
    if req[1] not in globals().keys():
        sys.stderr.write('Unable to find module: ' + req[1])
        return None
    the_module = globals ()[req[1]]
    method_name = op[req[0]] + '_Marshall'
    if not method_name in the_module.__dict__.keys():
        sys.stderr.write ('Unable to find method: ' + method_name)
        return None
    trace ('calling '+ req[1] + '.' + method_name + ' ' + repr (oldStyleDict))
    ret = the_module.__dict__[method_name](**oldStyleDict)
    sys.stderr.write (repr(ret))
    return ret

    
def handle_request (fd, req):
    trace ('<handle_request>')
    r = callMOF (req)
    if len (r) < 2 :
        ret = None
        rval = r[0]
    else:
        rval = r[0]
        ret = r[1]
    if rval == 0:
        write_success (fd, ret)
    else:
        write_failed (fd,1, 'Error occurred processing '+ repr (req))
    trace ('</handle_request>')



def main (argv):
    default_timeout_sec = 85
    socket.setdefaulttimeout(default_timeout_sec)
    fd = socket.fromfd (int (argv[1]), socket.AF_UNIX, socket.SOCK_STREAM)
    read = 1
    out = ''
    while 0 < read:
        try:
            req = read_request (fd)
            if req == None:
                read = -1
            else:
                trace ('Main: request len is '+str(len (req)))
                if sys.version < '3':
                    handle_request (fd, req)
                else:
                    try:
                        handle_request (fd, req)
                    except Exception as e:
                        trace ("Handle request failed for a python 3 resource provider. Exception from the resource provider: ")
                        trace (repr(e))
                        sys.stderr.write ('\nException in resource provider: ')
                        sys.stderr.write (repr(e) + "\n")
                        raise e 
        except socket.error:
            read = -1;
            sys.stderr.write('exception encountered')

##############################
try:
    try:
        trace ('socket: '+str(sys.argv[1]))
        
        pid_path=VarDir+'/run/python/'+repr(os.getuid())
        
        if not os.path.isdir(pid_path):
            os.system('mkdir -p ' + pid_path)
        pid_file=pid_path+'/dsc_python_client.pid'
        try:        
            F = open(pid_file,'w')
            F.write(str(os.getpid()) + "\n")
            F.flush()
            F.close()
        except:
             sys.stderr.write('Unable to create '+pid_file)
        trace ('using python version '+ sys.version) 
        sys.path.insert(0,'') # put the cwd in the path so we can find our module
        if sys.version < '2.6':
            trace (ScriptsDir + '/2.4x-2.5x')
            os.chdir(ScriptsDir + '/2.4x-2.5x')
        elif sys.version < '3':
            trace (ScriptsDir + '/2.6x-2.7x')
            os.chdir(ScriptsDir + '/2.6x-2.7x')
        else:
            trace (ScriptsDir + '/3.x')
            os.chdir (ScriptsDir + '/3.x')
            sys.path.append(ScriptsDir + '/3.x/Scripts')
        try:
            from Scripts import *
        except:
            trace ("Exception while Import: " + repr(sys.exc_info()))
            sys.stderr.write ('\nException while Import: ')
            sys.stderr.write (repr(sys.exc_info())+'\n')
            traceback.print_tb (sys.exc_info()[2])
            sys.stderr.write ('\n') 
        if __name__ == '__main__':
            main (sys.argv)
    
    
    except:
        sys.stderr.write ('\nException: ')
        sys.stderr.write (repr(sys.exc_info())+'\n')
        traceback.print_tb (sys.exc_info()[2])
        sys.stderr.write ('\n')

finally:
    sys.stderr.write ('Exiting - closing socket\n' )
    (socket.fromfd(int (sys.argv[1]), socket.AF_UNIX, socket.SOCK_STREAM)).close()