"""adodbapi.apibase - A python DB API 2.0 (PEP 249) interface to Microsoft ADO

Copyright (C) 2002 Henrik Ekelund, version 2.1 by Vernon Cole
* http://sourceforge.net/projects/pywin32
* http://sourceforge.net/projects/adodbapi
"""

import sys
import time
import datetime
import decimal
import numbers
# noinspection PyUnresolvedReferences
from . import ado_consts as adc

verbose = False  # debugging flag

onIronPython = sys.platform == 'cli'
if onIronPython:  # we need type definitions for odd data we may need to convert
    # noinspection PyUnresolvedReferences
    from System import DBNull, DateTime
    NullTypes = (type(None), DBNull)
else:
    DateTime = type(NotImplemented)  # should never be seen on win32
    NullTypes = type(None)

# --- define objects to smooth out Python3 <-> Python 2.x differences
unicodeType = str  #this line will be altered by 2to3.py to '= str'
longType = int        #this line will be altered by 2to3.py to '= int'
if sys.version[0] >= '3': #python 3.x
    StringTypes = str
    makeByteBuffer = bytes
    memoryViewType = memoryview
    _BaseException = Exception
else:                   #python 2.x
    # noinspection PyUnresolvedReferences
    from exceptions import Exception as _BaseException
    memoryViewType = type(buffer(''))
    makeByteBuffer = buffer
    StringTypes = (str,str)  # will be messed up by 2to3 but never used

try:                #jdhardy -- handle bytes under IronPython & Py3
    bytes
except NameError:
    bytes = str     # define it for old Pythons

# ------- Error handlers ------
def standardErrorHandler(connection, cursor, errorclass, errorvalue):
    err = (errorclass, errorvalue)
    try:
        connection.messages.append(err)
    except: pass
    if cursor is not None:
        try:
            cursor.messages.append(err)
        except: pass
    raise errorclass(errorvalue)

# Note: _BaseException is defined differently between Python 2.x and 3.x
class Error(_BaseException):
    pass   #Exception that is the base class of all other error
    #exceptions. You can use this to catch all errors with one
    #single 'except' statement. Warnings are not considered
    #errors and thus should not use this class as base. It must
    #be a subclass of the Python StandardError (defined in the
    #module exceptions).
class Warning(_BaseException):
    pass
class InterfaceError(Error):
    pass
class DatabaseError(Error):
    pass
class InternalError(DatabaseError):
    pass
class OperationalError(DatabaseError):
    pass
class ProgrammingError(DatabaseError):
    pass
class IntegrityError(DatabaseError):
    pass
class DataError(DatabaseError):
    pass
class NotSupportedError(DatabaseError):
    pass

class FetchFailedError(OperationalError):
    """
    Error is used by RawStoredProcedureQuerySet to determine when a fetch
    failed due to a connection being closed or there is no record set
    returned. (Non-standard, added especially for django)
    """
    pass
# # # # # ----- Type Objects and Constructors ----- # # # # #
#Many databases need to have the input in a particular format for binding to an operation's input parameters.
#For example, if an input is destined for a DATE column, then it must be bound to the database in a particular
#string format. Similar problems exist for "Row ID" columns or large binary items (e.g. blobs or RAW columns).
#This presents problems for Python since the parameters to the executeXXX() method are untyped.
#When the database module sees a Python string object, it doesn't know if it should be bound as a simple CHAR
#column, as a raw BINARY item, or as a DATE.
#
#To overcome this problem, a module must provide the constructors defined below to create objects that can
#hold special values. When passed to the cursor methods, the module can then detect the proper type of
#the input parameter and bind it accordingly.

#A Cursor Object's description attribute returns information about each of the result columns of a query.
#The type_code must compare equal to one of Type Objects defined below. Type Objects may be equal to more than
#one type code (e.g. DATETIME could be equal to the type codes for date, time and timestamp columns;
#see the Implementation Hints below for details).

#SQL NULL values are represented by the Python None singleton on input and output.

#Note: Usage of Unix ticks for database interfacing can cause troubles because of the limited date range they cover.

# def Date(year,month,day):
#     "This function constructs an object holding a date value. "
#     return dateconverter.date(year,month,day)  #dateconverter.Date(year,month,day)
#
# def Time(hour,minute,second):
#     "This function constructs an object holding a time value. "
#     return dateconverter.time(hour, minute, second) # dateconverter.Time(hour,minute,second)
#
# def Timestamp(year,month,day,hour,minute,second):
#     "This function constructs an object holding a time stamp value. "
#     return dateconverter.datetime(year,month,day,hour,minute,second)
#
# def DateFromTicks(ticks):
#     """This function constructs an object holding a date value from the given ticks value
#     (number of seconds since the epoch; see the documentation of the standard Python time module for details). """
#     return Date(*time.gmtime(ticks)[:3])
#
# def TimeFromTicks(ticks):
#     """This function constructs an object holding a time value from the given ticks value
#     (number of seconds since the epoch; see the documentation of the standard Python time module for details). """
#     return Time(*time.gmtime(ticks)[3:6])
#
# def TimestampFromTicks(ticks):
#     """This function constructs an object holding a time stamp value from the given
#     ticks value (number of seconds since the epoch;
#     see the documentation of the standard Python time module for details). """
#     return Timestamp(*time.gmtime(ticks)[:6])
#
# def Binary(aString):
#     """This function constructs an object capable of holding a binary (long) string value. """
#     b = makeByteBuffer(aString)
#     return b
# -----     Time converters ----------------------------------------------
class TimeConverter(object):  # this is a generic time converter skeleton
    def __init__(self):       # the details will be filled in by instances
        self._ordinal_1899_12_31=datetime.date(1899,12,31).toordinal()-1
                    # Use cls.types to compare if an input parameter is a datetime
        self.types = {type(self.Date(2000,1,1)),
                      type(self.Time(12,1,1)),
                      type(self.Timestamp(2000,1,1,12,1,1)),
                      datetime.datetime,
                      datetime.time,
                      datetime.date}
    def COMDate(self,obj):
        '''Returns a ComDate from a date-time'''
        try: # most likely a datetime
            tt=obj.timetuple()

            try:
                ms=obj.microsecond
            except:
                ms=0
            return self.ComDateFromTuple(tt, ms)
        except:  # might be a tuple
            try:
                return self.ComDateFromTuple(obj)
            except: # try an mxdate
                try:
                    return obj.COMDate()
                except:
                    raise ValueError('Cannot convert "%s" to COMdate.' % repr(obj))
    def ComDateFromTuple(self, t, microseconds=0):
        d = datetime.date(t[0],t[1],t[2])
        integerPart = d.toordinal() - self._ordinal_1899_12_31
        ms = (t[3]*3600 + t[4]*60 + t[5]) * 1000000 + microseconds
        fractPart = float(ms) / 86400000000.0
        return integerPart + fractPart
    def DateObjectFromCOMDate(self,comDate):
        'Returns an object of the wanted type from a ComDate'
        raise NotImplementedError   #"Abstract class"
    def Date(self,year,month,day):
        "This function constructs an object holding a date value. "
        raise NotImplementedError   #"Abstract class"
    def Time(self,hour,minute,second):
        "This function constructs an object holding a time value. "
        raise NotImplementedError   #"Abstract class"
    def Timestamp(self,year,month,day,hour,minute,second):
        "This function constructs an object holding a time stamp value. "
        raise NotImplementedError   #"Abstract class"
        # all purpose date to ISO format converter
    def DateObjectToIsoFormatString(self, obj):
        "This function should return a string in the format 'YYYY-MM-dd HH:MM:SS:ms' (ms optional) "
        try:  # most likely, a datetime.datetime
            s = obj.isoformat(' ')
        except (TypeError, AttributeError):
            if isinstance(obj, datetime.date):
                s = obj.isoformat() + ' 00:00:00'  # return exact midnight
            else:
                try: # maybe it has a strftime method, like mx
                    s = obj.strftime('%Y-%m-%d %H:%M:%S')
                except AttributeError: 
                    try:  #but may be time.struct_time
                        s = time.strftime('%Y-%m-%d %H:%M:%S', obj)
                    except:
                       raise ValueError('Cannot convert "%s" to isoformat' % repr(obj))
        return s

# -- Optional: if mx extensions are installed you may use mxDateTime ----
try:
    import mx.DateTime
    mxDateTime = True
except:
    mxDateTime = False
if mxDateTime:
    class mxDateTimeConverter(TimeConverter): # used optionally if installed
        def __init__(self):
            TimeConverter.__init__(self)
            self.types.add(type(mx.DateTime))
        def DateObjectFromCOMDate(self,comDate):
            return mx.DateTime.DateTimeFromCOMDate(comDate)
        def Date(self,year,month,day):
            return mx.DateTime.Date(year,month,day)
        def Time(self,hour,minute,second):
            return mx.DateTime.Time(hour,minute,second)
        def Timestamp(self,year,month,day,hour,minute,second):
            return mx.DateTime.Timestamp(year,month,day,hour,minute,second)
else:
    class mxDateTimeConverter(TimeConverter):
        pass    # if no mx is installed

class pythonDateTimeConverter(TimeConverter): # standard since Python 2.3
    def __init__(self):
        TimeConverter.__init__(self)
    def DateObjectFromCOMDate(self, comDate):
        if isinstance(comDate, datetime.datetime):
            odn = comDate.toordinal()
            tim = comDate.time()
            new = datetime.datetime.combine(datetime.datetime.fromordinal(odn), tim)
            return new
            # return comDate.replace(tzinfo=None) # make non aware
        elif isinstance(comDate, DateTime):
            fComDate = comDate.ToOADate() # ironPython clr Date/Time
        else:
            fComDate=float(comDate) #ComDate is number of days since 1899-12-31
        integerPart = int(fComDate)
        floatpart=fComDate-integerPart
        ##if floatpart == 0.0:
        ##    return datetime.date.fromordinal(integerPart + self._ordinal_1899_12_31)
        dte=datetime.datetime.fromordinal(integerPart + self._ordinal_1899_12_31) \
            + datetime.timedelta(milliseconds=floatpart*86400000)
        # millisecondsperday=86400000 # 24*60*60*1000
        return dte
    def Date(self,year,month,day):
        return datetime.date(year,month,day)
    def Time(self,hour,minute,second):
        return datetime.time(hour,minute,second)
    def Timestamp(self,year,month,day,hour,minute,second):
        return datetime.datetime(year,month,day,hour,minute,second)

class pythonTimeConverter(TimeConverter): # the old, ?nix type date and time
    def __init__(self): #caution: this Class gets confised by timezones and DST
        TimeConverter.__init__(self)
        self.types.add(time.struct_time)
    def DateObjectFromCOMDate(self,comDate):
        'Returns ticks since 1970'
        if isinstance(comDate,datetime.datetime):
            return comDate.timetuple()
        elif isinstance(comDate, DateTime): # ironPython clr date/time
            fcomDate = comDate.ToOADate()
        else:
            fcomDate = float(comDate)
        secondsperday=86400 # 24*60*60
        #ComDate is number of days since 1899-12-31, gmtime epoch is 1970-1-1 = 25569 days
        t=time.gmtime(secondsperday*(fcomDate-25569.0))
        return t  #year,month,day,hour,minute,second,weekday,julianday,daylightsaving=t
    def Date(self,year,month,day):
        return self.Timestamp(year,month,day,0,0,0)
    def Time(self,hour,minute,second):
        return time.gmtime((hour*60+minute)*60 + second)
    def Timestamp(self,year,month,day,hour,minute,second):
        return time.localtime(time.mktime((year,month,day,hour,minute,second,0,0,-1)))

base_dateconverter = pythonDateTimeConverter()

# ------ DB API required module attributes ---------------------
threadsafety=1  # TODO -- find out whether this module is actually BETTER than 1.

apilevel='2.0' #String constant stating the supported DB API level.

paramstyle='qmark' # the default parameter style

# ------ control for an extension which may become part of DB API 3.0 ---
accepted_paramstyles = ('qmark', 'named', 'format', 'pyformat', 'dynamic')

#------------------------------------------------------------------------------------------
# define similar types for generic conversion routines
adoIntegerTypes=(adc.adInteger,adc.adSmallInt,adc.adTinyInt,adc.adUnsignedInt,
                 adc.adUnsignedSmallInt,adc.adUnsignedTinyInt,
                 adc.adBoolean,adc.adError) #max 32 bits
adoRowIdTypes=(adc.adChapter,)          #v2.1 Rose
adoLongTypes=(adc.adBigInt,adc.adFileTime,adc.adUnsignedBigInt)
adoExactNumericTypes=(adc.adDecimal,adc.adNumeric,adc.adVarNumeric,adc.adCurrency)      #v2.3 Cole
adoApproximateNumericTypes=(adc.adDouble,adc.adSingle)                          #v2.1 Cole
adoStringTypes=(adc.adBSTR,adc.adChar,adc.adLongVarChar,adc.adLongVarWChar,
                adc.adVarChar,adc.adVarWChar,adc.adWChar)
adoBinaryTypes=(adc.adBinary,adc.adLongVarBinary,adc.adVarBinary)
adoDateTimeTypes=(adc.adDBTime, adc.adDBTimeStamp, adc.adDate, adc.adDBDate)
adoRemainingTypes=(adc.adEmpty,adc.adIDispatch,adc.adIUnknown,
                   adc.adPropVariant,adc.adArray,adc.adUserDefined,
                   adc.adVariant,adc.adGUID)

# this class is a trick to determine whether a type is a member of a related group of types. see PEP notes
class DBAPITypeObject(object):
    def __init__(self,valuesTuple):
        self.values = frozenset(valuesTuple)

    def __eq__(self,other):
        return other in self.values

    def __ne__(self, other):
        return other not in self.values

"""This type object is used to describe columns in a database that are string-based (e.g. CHAR). """
STRING   = DBAPITypeObject(adoStringTypes)

"""This type object is used to describe (long) binary columns in a database (e.g. LONG, RAW, BLOBs). """
BINARY   = DBAPITypeObject(adoBinaryTypes)

"""This type object is used to describe numeric columns in a database. """
NUMBER   = DBAPITypeObject(adoIntegerTypes + adoLongTypes + \
                           adoExactNumericTypes + adoApproximateNumericTypes)

"""This type object is used to describe date/time columns in a database. """

DATETIME = DBAPITypeObject(adoDateTimeTypes)
"""This type object is used to describe the "Row ID" column in a database. """
ROWID    = DBAPITypeObject(adoRowIdTypes)

OTHER = DBAPITypeObject(adoRemainingTypes)

# ------- utilities for translating python data types to ADO data types ---------------------------------
typeMap = { memoryViewType : adc.adVarBinary,
           float : adc.adDouble,
           type(None) : adc.adEmpty,
           str : adc.adBSTR, # this line will be altered by 2to3 to 'str:'
           bool :adc.adBoolean,          #v2.1 Cole
           decimal.Decimal : adc.adDecimal }
if longType != int: #not Python 3
    typeMap[longType] = adc.adBigInt  #works in python 2.x
    typeMap[int] = adc.adInteger
    typeMap[bytes] = adc.adBSTR     # 2.x string type
else:             #python 3.0 integrated integers
    ## Should this differentiate between an int that fits in a long and one that requires 64 bit datatype?
    typeMap[int] = adc.adBigInt
    typeMap[bytes] = adc.adVarBinary

def pyTypeToADOType(d):
    tp=type(d)
    try:
        return typeMap[tp]
    except KeyError:  #   The type was not defined in the pre-computed Type table
        from . import dateconverter
        if tp in dateconverter.types:  # maybe it is one of our supported Date/Time types
            return adc.adDate
        #  otherwise, attempt to discern the type by probing the data object itself -- to handle duck typing
        if isinstance(d, StringTypes):
            return adc.adBSTR
        if isinstance(d, numbers.Integral):
            return adc.adBigInt
        if isinstance(d, numbers.Real):
            return adc.adDouble
        raise DataError('cannot convert "%s" (type=%s) to ADO'%(repr(d),tp))

# # # # # # # # # # # # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# functions to convert database values to Python objects
#------------------------------------------------------------------------
# variant type : function converting variant to Python value
def variantConvertDate(v):
    from . import dateconverter  # this function only called when adodbapi is running
    return dateconverter.DateObjectFromCOMDate(v)

def cvtString(variant):  # use to get old action of adodbapi v1 if desired
    if onIronPython:
        try:
            return variant.ToString()
        except:
            pass
    return str(variant)

def cvtDecimal(variant): #better name
    return _convertNumberWithCulture(variant, decimal.Decimal)

def cvtNumeric(variant): #older name - don't break old code
    return cvtDecimal(variant)

def cvtFloat(variant):
    return _convertNumberWithCulture(variant, float)

def _convertNumberWithCulture(variant, f):
    try:
        return f(variant)
    except (ValueError,TypeError,decimal.InvalidOperation):
        try:
            europeVsUS = str(variant).replace(",",".")
            return f(europeVsUS)
        except (ValueError,TypeError,decimal.InvalidOperation): pass

def cvtInt(variant):
    return int(variant)

def cvtLong(variant):  # only important in old versions where long and int differ
    return int(variant)

def cvtBuffer(variant):
    return bytes(variant)

def cvtUnicode(variant):
    return str(variant) # will be altered by 2to3 to 'str(variant)'

def identity(x): return x

def cvtUnusual(variant):
    if verbose > 1:
        sys.stderr.write('Conversion called for Unusual data=%s\n' % repr(variant))
    if isinstance(variant, DateTime):  # COMdate or System.Date
        from .adodbapi import dateconverter  # this will only be called when adodbapi is in use, and very rarely
        return dateconverter.DateObjectFromCOMDate(variant)
    return variant  # cannot find conversion function -- just give the data to the user

def convert_to_python(variant, func): # convert DB value into Python value
    if isinstance(variant, NullTypes):  # IronPython Null or None
        return None
    return func(variant)  # call the appropriate conversion function

class MultiMap(dict): #builds a dictionary from {(sequence,of,keys) : function}
    """A dictionary of ado.type : function -- but you can set multiple items by passing a sequence of keys"""
    #useful for defining conversion functions for groups of similar data types.
    def __init__(self, aDict):
        for k, v in list(aDict.items()):
            self[k] = v # we must call __setitem__
    def __setitem__(self, adoType, cvtFn):
        "set a single item, or a whole sequence of items"
        try: # user passed us a sequence, set them individually
            for type in adoType:
                dict.__setitem__(self, type, cvtFn)
        except TypeError: # a single value fails attempt to iterate
            dict.__setitem__(self, adoType, cvtFn)

#initialize variantConversions dictionary used to convert SQL to Python
# this is the dictionary of default conversion functions, built by the class above.
# this becomes a class attribute for the Connection, and that attribute is used
# to build the list of column conversion functions for the Cursor
variantConversions = MultiMap( {
    adoDateTimeTypes : variantConvertDate,
    adoApproximateNumericTypes: cvtFloat,
    adoExactNumericTypes: cvtDecimal, # use to force decimal rather than unicode
    adoLongTypes : cvtLong,
    adoIntegerTypes: cvtInt,
    adoRowIdTypes: cvtInt,
    adoStringTypes: identity,
    adoBinaryTypes: cvtBuffer,
    adoRemainingTypes: cvtUnusual })

# # # # # classes to emulate the result of cursor.fetchxxx() as a sequence of sequences # # # # #
    # "an ENUM of how my low level records are laid out"
RS_WIN_32, RS_ARRAY, RS_REMOTE = list(range(1,4))

class SQLrow(object): # a single database row
    # class to emulate a sequence, so that a column may be retrieved by either number or name
    def __init__(self, rows, index): # "rows" is an _SQLrows object, index is which row
        self.rows = rows # parent 'fetch' container object
        self.index = index # my row number within parent
    def __getattr__(self, name): # used for row.columnName type of value access
        try:
            return self._getValue(self.rows.columnNames[name.lower()])
        except KeyError:
            raise AttributeError('Unknown column name "{}"'.format(name))
    def _getValue(self,key):  # key must be an integer
        if self.rows.recordset_format == RS_ARRAY: # retrieve from two-dimensional array
            v = self.rows.ado_results[key,self.index]
        elif self.rows.recordset_format == RS_REMOTE:
            v = self.rows.ado_results[self.index][key]
        else:# pywin32 - retrieve from tuple of tuples
            v = self.rows.ado_results[key][self.index]
        if self.rows.converters is NotImplemented:
            return v
        return convert_to_python(v, self.rows.converters[key])

    def __len__(self):
        return self.rows.numberOfColumns

    def __getitem__(self,key):       # used for row[key] type of value access
        if isinstance(key,int):       # normal row[1] designation
            try:
                return self._getValue(key)
            except IndexError:
                raise
        if isinstance(key, slice):
            indices = key.indices(self.rows.numberOfColumns)
            vl = [self._getValue(i) for i in range(*indices)]
            return tuple(vl)
        try:
            return self._getValue(self.rows.columnNames[key.lower()])  # extension row[columnName] designation
        except (KeyError, TypeError):
            er, st, tr = sys.exc_info()
            raise er('No such key as "%s" in %s'%(repr(key),self.__repr__())).with_traceback(tr)
    def __iter__(self):
        return iter(self.__next__())
    def __next__(self):
        for n in range(self.rows.numberOfColumns):
            yield self._getValue(n)
    def __repr__(self): # create a human readable representation
        taglist = sorted(list(self.rows.columnNames.items()), key=lambda x: x[1])
        s = "<SQLrow={"
        for name, i in taglist:
            s += name + ':' + repr(self._getValue(i)) + ', '
        return s[:-2] + '}>'
    def __str__(self): # create a pretty human readable representation
        return str(tuple(str(self._getValue(i)) for i in range(self.rows.numberOfColumns)))

    # TO-DO implement pickling an SQLrow directly
    #def __getstate__(self): return self.__dict__
    #def __setstate__(self, d): self.__dict__.update(d)
    # which basically tell pickle to treat your class just like a normal one,
    # taking self.__dict__ as representing the whole of the instance state,
    #  despite the existence of the __getattr__.
    # # # #
class SQLrows(object):
    # class to emulate a sequence for multiple rows using a container object
    def __init__(self, ado_results, numberOfRows, cursor):
        self.ado_results = ado_results # raw result of SQL get
        try:
            self.recordset_format = cursor.recordset_format
            self.numberOfColumns = cursor.numberOfColumns
            self.converters = cursor.converters
            self.columnNames = cursor.columnNames
        except AttributeError:
            self.recordset_format = RS_ARRAY
            self.numberOfColumns = 0
            self.converters = []
            self.columnNames = {}
        self.numberOfRows = numberOfRows

    def __len__(self):
        return self.numberOfRows

    def __getitem__(self, item):     # used for row or row,column access
        if not self.ado_results:
            return []
        if isinstance(item, slice): # will return a list of row objects
            indices = item.indices(self.numberOfRows)
            return [SQLrow(self, k) for k in range(*indices)]
        elif isinstance(item, tuple) and len(item)==2:
            # d = some_rowsObject[i,j] will return a datum from a two-dimension address
            i, j = item
            if not isinstance(j, int):
                try:
                    j = self.columnNames[j.lower()] # convert named column to numeric
                except KeyError:
                    raise KeyError('adodbapi: no such column name as "%s"'%repr(j))
            if self.recordset_format == RS_ARRAY: # retrieve from two-dimensional array
                v = self.ado_results[j,i]
            elif self.recordset_format == RS_REMOTE:
                v = self.ado_results[i][j]
            else: # pywin32 - retrieve from tuple of tuples
                v = self.ado_results[j][i]
            if self.converters is NotImplemented:
                return v
            return convert_to_python(v, self.converters[j])
        else:
            row = SQLrow(self, item) # new row descriptor
            return row
    def __iter__(self):
        return iter(self.__next__())

    def __next__(self):
        for n in range(self.numberOfRows):
            row = SQLrow(self, n)
            yield row
            # # # # #


    # # # # # functions to re-format SQL requests to other paramstyle requirements # # # # # # # # # #
def changeNamedToQmark(op):  #convert from 'named' paramstyle to ADO required '?'mark parameters
    outOp = ''
    outparms=[]
    chunks = op.split("'")   #quote all literals -- odd numbered list results are literals.
    inQuotes = False
    for chunk in chunks:
        if inQuotes: # this is inside a quote
            if chunk == '': # double apostrophe to quote one apostrophe
                outOp = outOp[:-1]  # so take one away
            else:
                outOp += "'"+chunk+"'" # else pass the quoted string as is.
        else: # is SQL code -- look for a :namedParameter
            while chunk: # some SQL string remains
                sp = chunk.split(':',1)
                outOp += sp[0]  # concat the part up to the :
                s = ''
                try:
                    chunk = sp[1]
                except IndexError:
                    chunk = None
                if chunk:  # there was a parameter - parse it out
                    i = 0
                    c = chunk[0]
                    while c.isalnum() or c == '_':
                        i += 1
                        try:
                            c = chunk[i]
                        except IndexError:
                            break
                    s = chunk[:i]
                    chunk = chunk[i:]
                if s:
                    outparms.append(s) # list the parameters in order
                    outOp += '?'  # put in the Qmark
        inQuotes = not inQuotes
    return outOp, outparms

def changeFormatToQmark(op):  #convert from 'format' paramstyle to ADO required '?'mark parameters
    outOp = ''
    outparams = []
    chunks = op.split("'")   #quote all literals -- odd numbered list results are literals.
    inQuotes = False
    for chunk in chunks:
        if inQuotes:
            if outOp != '' and chunk=='': # he used a double apostrophe to quote one apostrophe
                outOp = outOp[:-1]  # so take one away
            else:
                outOp += "'"+chunk+"'" # else pass the quoted string as is.
        else:  # is SQL code -- look for a %s parameter
            if '%(' in chunk:  # ugh! pyformat!
                while chunk:  # some SQL string remains
                    sp = chunk.split('%(', 1)
                    outOp += sp[0]  # concat the part up to the %
                    if len(sp) > 1:
                        try:
                            s, chunk = sp[1].split(')s', 1)  # find the ')s'
                        except ValueError:
                            raise ProgrammingError('Pyformat SQL has incorrect format near "%s"' % chunk)
                        outparams.append(s)
                        outOp += '?'  # put in the Qmark
                    else:
                        chunk = None
            else:  # proper '%s' format
                sp = chunk.split('%s')  # make each %s
                outOp += "?".join(sp)   # into ?
        inQuotes =  not inQuotes # every other chunk is a quoted string
    return outOp, outparams