#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (C) 2010-2017 Étienne Loks  <etienne.loks_AT_peacefrogsDOTnet>

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.

# This program 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# See the file COPYING for details.

"""
Forms definition
"""
import datetime
import re
import types

from django import forms
from django.core.urlresolvers import reverse
from django.core import validators
from django.forms.formsets import BaseFormSet, DELETION_FIELD_NAME
from django.utils import formats, translation
from django.utils.functional import lazy
from django.utils.safestring import mark_safe
from django.utils.translation import ugettext_lazy as _

from bootstrap_datepicker.widgets import DatePicker, DATE_FORMAT, DateField
import models
import widgets
from ishtar_common.utils import MultiValueDict


# from formwizard.forms import NamedUrlSessionFormWizard


class NamedUrlSessionFormWizard(forms.Form):
    def __init__(self, form_list, condition_list={}, url_name=''):
        self.form_list = dict(form_list)
        self.condition_list = condition_list
        self.url_name = url_name
        super(NamedUrlSessionFormWizard, self).__init__(self)

    def rindex(self, idx):
        return self.url_name.rindex(idx)


def my_reverse(*args, **kwargs):
    """
    Custom reverse method in order to evaluate lazy args
    """
    if 'args' in kwargs:
        my_args = []
        for arg in kwargs['args']:
            if callable(arg):
                my_args.append(unicode(arg()))
            else:
                my_args.append(unicode(arg))
        kwargs['args'] = my_args
    return reverse(*args, **kwargs)


reverse_lazy = lazy(my_reverse, unicode)

regexp_name = re.compile(r"^[,:/\w\-'\"() \&\[\]@]+$", re.UNICODE)
name_validator = validators.RegexValidator(
    regexp_name,
    _(u"Enter a valid name consisting of letters, spaces and hyphens."),
    'invalid')


class FloatField(forms.FloatField):
    """
    Allow the use of comma for separating float fields
    """
    def clean(self, value):
        if value and (isinstance(value, unicode) or isinstance(value, str)):
            value = value.replace(',', '.').replace('%', '')
        return super(FloatField, self).clean(value)


class FinalForm(forms.Form):
    final = True
    form_label = _(u"Confirm")


class FinalDeleteForm(FinalForm):
    confirm_msg = " "
    confirm_end_msg = _(u"Are you sure you want to delete?")


def get_readonly_clean(key):
    def func(self):
        instance = getattr(self, 'instance', None)
        if instance and getattr(instance, key):
            return getattr(instance, key)
        else:
            return self.cleaned_data[key]
    return func


class CustomForm(object):
    form_admin_name = ""
    form_slug = ""
    need_user_for_initialization = True

    def __init__(self, *args, **kwargs):
        current_user = None
        if 'user' in kwargs:
            try:
                current_user = kwargs.pop('user').ishtaruser
            except AttributeError:
                pass
        super(CustomForm, self).__init__(*args, **kwargs)
        available, excluded = self.check_availability_and_excluded_fields(
            current_user)
        for exc in excluded:
            if hasattr(self, 'fields'):
                self.remove_field(exc)
            else:
                # formset
                for form in self.forms:
                    if exc in form.fields:
                        form.fields.pop(exc)

    def are_available(self, keys):
        for k in keys:
            if k not in self.fields:
                return False
        return True

    def remove_field(self, key):
        if key in self.fields:
            self.fields.pop(key)

    @classmethod
    def check_availability_and_excluded_fields(cls, current_user):
        if not current_user:
            return True, []
        base_q = {"form": cls.form_slug, 'available': True}
        # order is important : try for user, user type then all
        query_dicts = []
        if current_user:
            dct = base_q.copy()
            dct.update({'users__pk': current_user.pk})
            query_dicts = [dct]
            for user_type in current_user.person.person_types.all():
                dct = base_q.copy()
                dct.update({'user_types__pk': user_type.pk}),
                query_dicts.append(dct)
        dct = base_q.copy()
        dct.update({'apply_to_all': True})
        query_dicts.append(dct)
        excluded_lst = []
        for query_dict in query_dicts:
            q = models.CustomForm.objects.filter(**query_dict)
            if not q.count():
                continue
            # todo: prevent multiple result in database
            form = q.all()[0]
            if not form.enabled:
                return False, []
            for excluded in form.excluded_fields.all():
                # could have be filtered previously
                excluded_lst.append(excluded.field)
            break
        return True, excluded_lst

    @classmethod
    def get_custom_fields(cls):
        if hasattr(cls, 'base_fields'):
            fields = cls.base_fields
        else:
            # formset
            fields = cls.form.base_fields
        customs = []
        for key in fields:
            field = fields[key]
            # cannot customize display of required and hidden field
            # field with no label are also rejected
            if field.required or field.widget.is_hidden or not field.label:
                continue
            customs.append((key, field.label))
        return sorted(customs, key=lambda x: x[1])


class FormSet(CustomForm, BaseFormSet):
    def __init__(self, *args, **kwargs):
        self.readonly = False
        if 'readonly' in kwargs:
            self.readonly = kwargs.pop('readonly')
            self.can_delete = False
            # no extra fields
            if 'data' in kwargs:
                prefix = ""
                if "prefix" in kwargs:
                    prefix = kwargs['prefix']
                if prefix + '-INITIAL_FORMS' in kwargs['data']:
                    kwargs['data'][prefix + '-TOTAL_FORMS'] = \
                        kwargs["data"][prefix + '-INITIAL_FORMS']
        super(FormSet, self).__init__(*args, **kwargs)

    def check_duplicate(self, key_names, error_msg=""):
        """Check for duplicate items in the formset"""
        if any(self.errors):
            return
        if not error_msg:
            error_msg = _("There are identical items.")
        items = []
        for i in range(0, self.total_form_count()):
            form = self.forms[i]
            if not form.is_valid():
                continue
            item = [key_name in form.cleaned_data and
                    form.cleaned_data[key_name]
                    for key_name in key_names]
            if not [v for v in item if v]:
                continue
            if item in items:
                raise forms.ValidationError, error_msg
            items.append(item)

    def add_fields(self, form, index):
        super(FormSet, self).add_fields(form, index)
        if self.readonly:
            for k in form.fields:
                # django 1.9: use disabled
                form.fields[k].widget.attrs['readonly'] = True
                clean = get_readonly_clean(k)
                clean.__name__ = 'clean_' + k
                clean.__doc__ = 'autogenerated: clean_' + k
                setattr(form, clean.__name__, types.MethodType(clean, form))
        if self.can_delete:
            form.fields[DELETION_FIELD_NAME].label = ''
            form.fields[DELETION_FIELD_NAME].widget = widgets.DeleteWidget()


class FieldType(object):
    def __init__(self, key, model, is_multiple=False, extra_args=None):
        self.key = key
        self.model = model
        self.is_multiple = is_multiple
        self.extra_args = extra_args

    def get_choices(self, initial=None):
        args = {
            'empty_first': not self.is_multiple,
            'initial': initial
        }
        if self.extra_args:
            args.update(self.extra_args)
        return self.model.get_types(**args)

    def get_help(self):
        args = {}
        if self.extra_args:
            args.update(self.extra_args)
        return self.model.get_help(**args)


class FormHeader(object):
    def __init__(self, label, level=4):
        self.label = label
        self.level = level

    def render(self):
        return mark_safe(u"<h{level}>{label}</h{level}>".format(
            label=self.label, level=self.level
        ))


class IshtarForm(forms.Form):
    TYPES = []  # FieldType list
    PROFILE_FILTER = {}  # profile key associated to field list
    HEADERS = {}  # field key associated to FormHeader instance

    def __init__(self, *args, **kwargs):
        super(IshtarForm, self).__init__(*args, **kwargs)
        if self.PROFILE_FILTER:
            profile = models.get_current_profile()
            for profile_key in self.PROFILE_FILTER:
                if not getattr(profile, profile_key):
                    for field_key in self.PROFILE_FILTER[profile_key]:
                        self.fields.pop(field_key)
        for field in self.TYPES:
            self._init_type(field)
        for k in self.fields:
            if not hasattr(self.fields[k].widget, 'NO_FORM_CONTROL'):
                cls = 'form-control'
                if 'class' in self.fields[k].widget.attrs:
                    cls = self.fields[k].widget.attrs['class'] + " " + cls
                self.fields[k].widget.attrs['class'] = cls
            widget = self.fields[k].widget
            if not isinstance(widget, DatePicker):
                continue
            lang = translation.get_language()
            widget.options['language'] = lang
            if lang in DATE_FORMAT:
                widget.options['format'] = DATE_FORMAT[lang]
            if 'autoclose' not in widget.options:
                widget.options['autoclose'] = 'true'
            widget.options['todayHighlight'] = 'true'

    def _init_type(self, field):
        if field.key not in self.fields:
            return
        self.fields[field.key].choices = field.get_choices()
        self.fields[field.key].help_text = field.get_help()


class TableSelect(IshtarForm):
    def __init__(self, *args, **kwargs):
        super(TableSelect, self).__init__(*args, **kwargs)
        # no field is required for search
        for k in self.fields:
            self.fields[k].required = False
            cls = 'form-control'
            if k == 'search_vector':
                cls += " search-vector"
            self.fields[k].widget.attrs['class'] = cls
        key = self.fields.keys()[0]
        self.fields[key].widget.attrs['autofocus'] = 'autofocus'

    def get_input_ids(self):
        return self.fields.keys()


def get_now():
    format = formats.get_format('DATE_INPUT_FORMATS')[0]
    value = datetime.datetime.now().strftime(format)
    return value


class ClosingDateFormSelection(IshtarForm):
    form_label = _("Closing date")
    end_date = DateField(label=_(u"Closing date"))

    def __init__(self, *args, **kwargs):
        if 'initial' not in kwargs:
            kwargs['initial'] = {}
        if not kwargs['initial'].get('end_date', None):
            kwargs['initial']['end_date'] = datetime.date.today()
        super(ClosingDateFormSelection, self).__init__(*args, **kwargs)


def get_form_selection(
        class_name, label, key, model, base_form, get_url,
        not_selected_error=_(u"You should select an item."), new=False,
        new_message=_(u"Add a new item"), get_full_url=None):
    """
    Generate a class selection form
        class_name -- name of the class
        label -- label of the form
        key -- model,
        base_form -- base form to select
        get_url -- url to get the item
        not_selected_error -- message displayed when no item is selected
        new -- can add new items
        new_message -- message of link to add new items
    """
    attrs = {'_main_key': key,
             '_not_selected_error': not_selected_error,
             'form_label': label,
             'associated_models': {key: model},
             'currents': {key: model}}
    widget_kwargs = {"new": new, "new_message": new_message}
    if get_full_url:
        widget_kwargs['source_full'] = reverse_lazy(get_full_url)
    attrs[key] = forms.IntegerField(
        label="", required=False,
        validators=[models.valid_id(model)],
        widget=widgets.DataTable(reverse_lazy(get_url), base_form, model,
                                 **widget_kwargs))

    def clean(self):
        cleaned_data = self.cleaned_data
        if self._main_key not in cleaned_data \
           or not cleaned_data[self._main_key]:
            raise forms.ValidationError(self._not_selected_error)
        return cleaned_data
    attrs['clean'] = clean
    attrs['SEARCH_AND_SELECT'] = True
    return type(class_name, (forms.Form,), attrs)


def get_data_from_formset(data):
    """
    convert ['formname-wizardname-1-public_domain': [u'on'], ...] to
    [{'public_domain': 'off'}, {'public_domain': 'on'}]
    """
    values = []
    for k in data:
        if not data[k]:
            continue
        keys = k.split('-')
        if len(keys) < 3:
            continue
        try:
            idx = int(keys[-2])
        except ValueError:
            continue
        while len(values) < (idx + 1):
            values.append({})
        field_name = keys[-1]
        values[idx][field_name] = data[k]
    return values


class ManageOldType(IshtarForm):
    def __init__(self, *args, **kwargs):
        """
        init_data is used to manage deactivated items in list when editing
        old data
        """
        prefix = kwargs.get('prefix') or ''
        self.init_data = {}
        if 'data' in kwargs and kwargs['data']:
            for k in kwargs['data']:
                if prefix not in k:
                    continue
                new_k = k[len(prefix) + 1:]
                if hasattr(kwargs['data'], 'getlist'):
                    items = kwargs['data'].getlist(k)
                else:
                    items = [kwargs['data'][k]]
                for val in items:
                    if not val:
                        continue
                    if new_k not in self.init_data:
                        self.init_data[new_k] = []
                    self.init_data[new_k].append(val)
        if 'initial' in kwargs and kwargs['initial']:
            for k in kwargs['initial']:
                if k not in self.init_data or not self.init_data[k]:
                    if hasattr(kwargs['initial'], 'getlist'):
                        items = kwargs['initial'].getlist(k)
                    else:
                        items = [kwargs['initial'][k]]
                    for val in items:
                        if not val:
                            continue
                        if k not in self.init_data:
                            self.init_data[k] = []
                        self.init_data[k].append(val)
        self.init_data = MultiValueDict(self.init_data)
        super(ManageOldType, self).__init__(*args, **kwargs)
        for field in self.TYPES:
            self._init_type(field)

    def _init_type(self, field):
        if field.key not in self.fields:
            return
        self.fields[field.key].choices = field.get_choices(
            initial=self.init_data.get(field.key))
        self.fields[field.key].help_text = field.get_help()


class DocumentGenerationForm(forms.Form):
    """
    Form to generate document by choosing the template
    """
    _associated_model = None  # ex: AdministrativeAct
    # ex: 'archaeological_operations.models.AdministrativeAct'
    _associated_object_name = ''
    document_template = forms.ChoiceField(label=_("Template"), choices=[])

    def __init__(self, *args, **kwargs):
        super(DocumentGenerationForm, self).__init__(*args, **kwargs)
        self.fields['document_template'].choices = \
            models.DocumentTemplate.get_tuples(
                dct={'associated_object_name': self._associated_object_name})

    def save(self, object_pk):
        try:
            c_object = self._associated_model.objects.get(pk=object_pk)
        except self._associated_model.DoesNotExist:
            return
        try:
            template = models.DocumentTemplate.objects.get(
                pk=self.cleaned_data.get('document_template'))
        except models.DocumentTemplate.DoesNotExist:
            return
        return template.publish(c_object)