# -*- coding: iso-8859-1 -*-

# copyright 2003-2014 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr

#

# This file is part of CubicWeb.

#

# CubicWeb is free software: you can redistribute it and/or modify it under the

# terms of the GNU Lesser General Public License as published by the Free

# Software Foundation, either version 2.1 of the License, or (at your option)

# any later version.

#

# CubicWeb is distributed in the hope that it will be useful, but WITHOUT

# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS

# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more

# details.

#

# You should have received a copy of the GNU Lesser General Public License along

# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

"""This modules defines func / methods for creating test repositories"""

from __future__ import print_function

__docformat__ = "restructuredtext en"

import logging

from random import randint, choice

from copy import deepcopy

from datetime import datetime, date, time, timedelta

from decimal import Decimal

from six import text_type, add_metaclass

from six.moves import range

from logilab.common import attrdict

from logilab.mtconverter import xml_escape

from yams.constraints import (SizeConstraint, StaticVocabularyConstraint,

                              IntervalBoundConstraint, BoundaryConstraint,

                              Attribute, actual_value)

from rql.utils import decompose_b26 as base_decompose_b26

from cubicweb import Binary

from cubicweb.schema import RQLConstraint

def custom_range(start, stop, step):

    while start < stop:

        yield start

        start += step

def decompose_b26(index, ascii=False):

    """return a letter (base-26) decomposition of index"""

    if ascii:

        return base_decompose_b26(index)

    return base_decompose_b26(index, u'�abcdefghijklmnopqrstuvwxyz')

def get_max_length(eschema, attrname):

    """returns the maximum length allowed for 'attrname'"""

    for cst in eschema.rdef(attrname).constraints:

        if isinstance(cst, SizeConstraint) and cst.max:

            return cst.max

    return 300

    #raise AttributeError('No Size constraint on attribute "%s"' % attrname)

_GENERATED_VALUES = {}

class _ValueGenerator(object):

    """generates integers / dates / strings / etc. to fill a DB table"""

    def __init__(self, eschema, choice_func=None):

        """<choice_func> is a function that returns a list of possible

        choices for a given entity type and an attribute name. It should

        looks like :

            def values_for(etype, attrname):

                # some stuff ...

                return alist_of_acceptable_values # or None

        """

        self.choice_func = choice_func

        self.eschema = eschema

    def generate_attribute_value(self, entity, attrname, index=1, **kwargs):

        if attrname in entity:

            return entity[attrname]

        eschema = self.eschema

        if not eschema.has_unique_values(attrname):

            value = self.__generate_value(entity, attrname, index, **kwargs)

        else:

            value = self.__generate_value(entity, attrname, index, **kwargs)

            while value in _GENERATED_VALUES.get((eschema, attrname), ()):

                index += 1

                value = self.__generate_value(entity, attrname, index, **kwargs)

            _GENERATED_VALUES.setdefault((eschema, attrname), set()).add(value)

        entity[attrname] = value

        return value

    def __generate_value(self, entity, attrname, index, **kwargs):

        """generates a consistent value for 'attrname'"""

        eschema = self.eschema

        attrtype = str(eschema.destination(attrname)).lower()

        # Before calling generate_%s functions, try to find values domain

        if self.choice_func is not None:

            values_domain = self.choice_func(eschema, attrname)

            if values_domain is not None:

                return choice(values_domain)

        gen_func = getattr(self, 'generate_%s_%s' % (eschema, attrname),

                           getattr(self, 'generate_Any_%s' % attrname, None))

        if gen_func is not None:

            return gen_func(entity, index, **kwargs)

        # If no specific values domain, then generate a dummy value

        gen_func = getattr(self, 'generate_%s' % (attrtype))

        return gen_func(entity, attrname, index, **kwargs)

    def generate_string(self, entity, attrname, index, format=None):

        """generates a consistent value for 'attrname' if it's a string"""

        # First try to get choices

        choosed = self.get_choice(entity, attrname)

        if choosed is not None:

            return choosed

        # All other case, generate a default string

        attrlength = get_max_length(self.eschema, attrname)

        num_len = numlen(index)

        if num_len >= attrlength:

            ascii = self.eschema.rdef(attrname).internationalizable

            return ('&'+decompose_b26(index, ascii))[:attrlength]

        # always use plain text when no format is specified

        attrprefix = attrname[:max(attrlength-num_len-1, 0)]

        if format == 'text/html':

            value = u'<span>�%s<b>%d</b></span>' % (attrprefix, index)

        elif format == 'text/rest':

            value = u"""

title

-----

* %s

* %d

* �&

""" % (attrprefix, index)

        else:

            value = u'�&%s%d' % (attrprefix, index)

        return value[:attrlength]

    def generate_password(self, entity, attrname, index):

        """generates a consistent value for 'attrname' if it's a password"""

        return u'toto'

    def generate_integer(self, entity, attrname, index):

        """generates a consistent value for 'attrname' if it's an integer"""

        return self._constrained_generate(entity, attrname, 0, 1, index)

    generate_int = generate_bigint = generate_integer

    def generate_float(self, entity, attrname, index):

        """generates a consistent value for 'attrname' if it's a float"""

        return self._constrained_generate(entity, attrname, 0.0, 1.0, index)

    def generate_decimal(self, entity, attrname, index):

        """generates a consistent value for 'attrname' if it's a float"""

        return Decimal(str(self.generate_float(entity, attrname, index)))

    def generate_datetime(self, entity, attrname, index):

        """generates a random date (format is 'yyyy-mm-dd HH:MM')"""

        base = datetime(randint(2000, 2004), randint(1, 12), randint(1, 28), 11, index%60)

        return self._constrained_generate(entity, attrname, base, timedelta(hours=1), index)

    generate_tzdatetime = generate_datetime # XXX implementation should add a timezone

    def generate_date(self, entity, attrname, index):

        """generates a random date (format is 'yyyy-mm-dd')"""

        base = date(randint(2000, 2010), 1, 1) + timedelta(randint(1, 365))

        return self._constrained_generate(entity, attrname, base, timedelta(days=1), index)

    def generate_interval(self, entity, attrname, index):

        """generates a random date (format is 'yyyy-mm-dd')"""

        base = timedelta(randint(1, 365))

        return self._constrained_generate(entity, attrname, base, timedelta(days=1), index)

    def generate_time(self, entity, attrname, index):

        """generates a random time (format is ' HH:MM')"""

        return time(11, index%60) #'11:%02d' % (index % 60)

    generate_tztime = generate_time # XXX implementation should add a timezone

    def generate_bytes(self, entity, attrname, index, format=None):

        fakefile.filename = u"file_%s" % attrname

        return fakefile

    def generate_boolean(self, entity, attrname, index):

        """generates a consistent value for 'attrname' if it's a boolean"""

        return index % 2 == 0

    def _constrained_generate(self, entity, attrname, base, step, index):

        choosed = self.get_choice(entity, attrname)

        if choosed is not None:

            return choosed

        # ensure index > 0

        index += 1

        minvalue, maxvalue = self.get_bounds(entity, attrname)

        if maxvalue is None:

            if minvalue is not None:

                base = max(minvalue, base)

            maxvalue = base + index * step

        if minvalue is None:

            minvalue = maxvalue - (index * step) # i.e. randint(-index, 0)

        return choice(list(custom_range(minvalue, maxvalue, step)))

    def _actual_boundary(self, entity, attrname, boundary):

        if isinstance(boundary, Attribute):

            # ensure we've a value for this attribute

            entity[attrname] = None # infinite loop safety belt

            if not boundary.attr in entity:

                self.generate_attribute_value(entity, boundary.attr)

            boundary = actual_value(boundary, entity)

        return boundary

    def get_bounds(self, entity, attrname):

        minvalue = maxvalue = None

        for cst in self.eschema.rdef(attrname).constraints:

            if isinstance(cst, IntervalBoundConstraint):

                minvalue = self._actual_boundary(entity, attrname, cst.minvalue)

                maxvalue = self._actual_boundary(entity, attrname, cst.maxvalue)

            elif isinstance(cst, BoundaryConstraint):

                if cst.operator[0] == '<':

                    maxvalue = self._actual_boundary(entity, attrname, cst.boundary)

                else:

                    minvalue = self._actual_boundary(entity, attrname, cst.boundary)

        return minvalue, maxvalue

    def get_choice(self, entity, attrname):

        """generates a consistent value for 'attrname' if it has some static

        vocabulary set, else return None.

        """

        for cst in self.eschema.rdef(attrname).constraints:

            if isinstance(cst, StaticVocabularyConstraint):

                return text_type(choice(cst.vocabulary()))

        return None

    # XXX nothing to do here

    def generate_Any_data_format(self, entity, index, **kwargs):

        # data_format attribute of File has no vocabulary constraint, we

        # need this method else stupid values will be set which make mtconverter

        # raise exception

        return u'application/octet-stream'

    def generate_Any_content_format(self, entity, index, **kwargs):

        # content_format attribute of EmailPart has no vocabulary constraint, we

        # need this method else stupid values will be set which make mtconverter

        # raise exception

        return u'text/plain'

    def generate_CWDataImport_log(self, entity, index, **kwargs):

        # content_format attribute of EmailPart has no vocabulary constraint, we

        # need this method else stupid values will be set which make mtconverter

        # raise exception

        logs =  [u'%s\t%s\t%s\t%s<br/>' % (logging.ERROR, 'http://url.com?arg1=hop&arg2=hip',

                                           1, xml_escape('hjoio&oio"'))]

        return u'<br/>'.join(logs)

class autoextend(type):

    def __new__(mcs, name, bases, classdict):

        for attrname, attrvalue in classdict.items():

            if callable(attrvalue):

                if attrname.startswith('generate_') and \

                       attrvalue.func_code.co_argcount < 2:

                    raise TypeError('generate_xxx must accept at least 1 argument')

                setattr(_ValueGenerator, attrname, attrvalue)

        return type.__new__(mcs, name, bases, classdict)

@add_metaclass(autoextend)

class ValueGenerator(_ValueGenerator):

    pass

def _default_choice_func(etype, attrname):

    """default choice_func for insert_entity_queries"""

    return None

def insert_entity_queries(etype, schema, vreg, entity_num,

                          choice_func=_default_choice_func):

    """returns a list of 'add entity' queries (couples query, args)

    :type etype: str

    :param etype: the entity's type

    :type schema: cubicweb.schema.Schema

    :param schema: the instance schema

    :type entity_num: int

    :param entity_num: the number of entities to insert

    XXX FIXME: choice_func is here for *historical* reasons, it should

               probably replaced by a nicer way to specify choices

    :type choice_func: function

    :param choice_func: a function that takes an entity type, an attrname and

                        returns acceptable values for this attribute

    """

    queries = []

    for index in range(entity_num):

        restrictions = []

        args = {}

        for attrname, value in make_entity(etype, schema, vreg, index, choice_func).items():

            restrictions.append('X %s %%(%s)s' % (attrname, attrname))

            args[attrname] = value

        if restrictions:

            queries.append(('INSERT %s X: %s' % (etype, ', '.join(restrictions)),

                            args))

            assert not 'eid' in args, args

        else:

            queries.append(('INSERT %s X' % etype, {}))

    return queries

def make_entity(etype, schema, vreg, index=0, choice_func=_default_choice_func,

                form=False):

    """generates a random entity and returns it as a dict

    by default, generate an entity to be inserted in the repository

    elif form, generate an form dictionary to be given to a web controller

    """

    eschema = schema.eschema(etype)

    valgen = ValueGenerator(eschema, choice_func)

    entity = attrdict()

    # preprocessing to deal with _format fields

    attributes = []

    relatedfields = {}

    for rschema, attrschema in eschema.attribute_definitions():

        attrname = rschema.type

        if attrname == 'eid':

            # don't specify eids !

            continue

        if attrname.endswith('_format') and attrname[:-7] in eschema.subject_relations():

            relatedfields[attrname[:-7]] = attrschema

        else:

            attributes.append((attrname, attrschema))

    for attrname, attrschema in attributes:

        if attrname in relatedfields:

            # first generate a format and record it

            format = valgen.generate_attribute_value(entity, attrname + '_format', index)

            # then a value coherent with this format

            value = valgen.generate_attribute_value(entity, attrname, index, format=format)

        else:

            value = valgen.generate_attribute_value(entity, attrname, index)

        if form: # need to encode values

            if attrschema.type == 'Bytes':

                # twisted way

                fakefile = value

                filename = value.filename

                value = (filename, u"text/plain", fakefile)

            elif attrschema.type == 'Date':

                value = value.strftime(vreg.property_value('ui.date-format'))

            elif attrschema.type == 'Datetime':

                value = value.strftime(vreg.property_value('ui.datetime-format'))

            elif attrschema.type == 'Time':

                value = value.strftime(vreg.property_value('ui.time-format'))

            elif attrschema.type == 'Float':

                fmt = vreg.property_value('ui.float-format')

                value = fmt % value

            else:

                value = text_type(value)

    return entity

def select(constraints, cnx, selectvar='O', objtype=None):

    """returns list of eids matching <constraints>

    <selectvar> should be either 'O' or 'S' to match schema definitions

    """

    try:

        rql = 'Any %s WHERE %s' % (selectvar, constraints)

        if objtype:

            rql += ', %s is %s' % (selectvar, objtype)

        rset = cnx.execute(rql)

    except Exception:

        print("could restrict eid_list with given constraints (%r)" % constraints)

        return []

    return set(eid for eid, in rset.rows)