# -*- coding: utf-8 -*-

__author__ = 'marcos.medeiros'

from django.db import models
from django.db.models.fields.related import ForeignObjectRel
import datetime
import decimal
import inspect
import locale

from django.template import loader, Context

_filter_templates = 'rapid/filters/'
_filter_url_parameter = 'filter'

class FilterOperator:
    def __init__(self, display, query, multiple=False):
        self.display = display
        self.query = query
        self.multiple = multiple


class FilterValue:
    available_operations = []
    selection_template = _filter_templates + 'key_value.html'

    def __init__(self, field, url_value=''):
        self.value = None
        self.field = field
        raise NotImplementedError

    def query_value(self):
        return self.value

    def url_value(self):
        return unicode(self.value)

    def operator_from_url(self, url_value):
        for o in self.available_operations:
            if unicode(o.query) == unicode(url_value):
                return o
        return None


class IntegralFilter(FilterValue):
    available_operations = [
        FilterOperator('igual a', 'exact'),
        FilterOperator('maior que', 'gt'),
        FilterOperator('maior ou igual a', 'gte'),
        FilterOperator('menor que', 'lt'),
        FilterOperator('menor ou igual a', 'lte'),
    ]

    def __init__(self, field, url_value=0):
        self.value = int(url_value)


class BooleanFilter(FilterValue):
    available_operations = [
        FilterOperator('valor', 'exact'),
    ]

    def __init__(self, field, url_value='true'):
        self.value = bool(url_value)

    def __unicode__(self):
        return 'true' if self.value else ''


class TextFilter(FilterValue):
    available_operations = [
        FilterOperator('igual a', 'iexact'),
        FilterOperator(u'começa com', 'istartswith'),
        FilterOperator('acaba com', 'iendswith'),
        FilterOperator('contém', 'icontains'),
    ]

    def __init__(self, field, url_value=''):
        self.value = url_value

    def url_value(self):
        return self.value if self.value else ''


class DateTimeFilter(FilterValue):
    available_operations = [
        FilterOperator('igual a', 'exact'),
        FilterOperator('maior que', 'gt'),
        FilterOperator('maior ou igual a', 'gte'),
        FilterOperator('menor que', 'lt'),
        FilterOperator('menor ou igual a', 'lte'),
    ]

    dateformat = '%Y:%m:%d:%H:%M:%S'

    def __init__(self, field, url_value=None):
        if url_value:
            self.value = datetime.datetime.strptime(url_value, self.dateformat)
        else:
            self.value = datetime.datetime.now()

    def url_value(self):
        return self.value.strftime(self.dateformat)


class RealFilter(FilterValue):
    available_operations = [
        FilterOperator('igual a', 'exact'),
        FilterOperator('maior que', 'gt'),
        FilterOperator('maior ou igual a', 'gte'),
        FilterOperator('menor que', 'lt'),
        FilterOperator('menor ou igual a', 'lte'),
    ]

    def __init__(self, field, url_value=0.0):
        self.value = decimal.Decimal(url_value)


class TimeFilter(DateTimeFilter):
    available_operations = [
        FilterOperator('igual a', 'exact'),
        FilterOperator('maior que', 'gt'),
        FilterOperator('maior ou igual a', 'gte'),
        FilterOperator('menor que', 'lt'),
        FilterOperator('menor ou igual a', 'lte'),
    ]

    dateformat = 'HH:MM:SS'


class RelationFilter(FilterValue):
    available_operations = [
        FilterOperator('igual a', 'exact'),
        FilterOperator('na lista', 'in'),
    ]

    def __init__(self, field, url_value=''):
        model = field.related_model()
        self.model = model
        self.value = [model.default_manager().filter(pk__in=int(v)) for v in url_value.split(':') if v]

    def url_value(self):
        return ':'.join([str(v.pk) for v in self.value])


field_type_dispatcher = {
    models.AutoField: IntegralFilter,
    models.BigIntegerField: IntegralFilter,
    #models.BinaryField:
    #models.BooleanField: BooleanFilter,
    models.CharField: TextFilter,
    #models.CommaSeparatedIntegerField:
    #models.DateField: DateTimeFilter,
    #models.DateTimeField: DateTimeFilter,
    #models.DecimalField: RealFilter,
    #models.DurationField:TimeFilter,
    models.EmailField: TextFilter,
    #models.FileField:
    #models.FilePathField:
    models.FloatField: RealFilter,
    #models.ImageField:
    models.IntegerField: IntegralFilter,
    #models.IPAddressField:
    #models.GenericIPAddressField:
    #models.NullBooleanField: BooleanFilter,
    models.PositiveIntegerField: IntegralFilter,
    models.PositiveSmallIntegerField: IntegralFilter,
    #models.SlugField:
    models.SmallIntegerField: IntegralFilter,
    models.TextField: TextFilter,
    #models.TimeField: TimeFilter,
    #models.URLField:
    #models.UUIDField:
    #models.ForeignKey: RelationFilter,
    #models.ManyToManyField: RelationFilter,
    #models.OneToOneField: RelationFilter,
    #models.Manager: RelationFilter,
    #ForeignObjectRel: RelationFilter,
}

def _get_field_type(field):
    tt = inspect.getmro(type(field.field))
    for t in tt:
        v = field_type_dispatcher.get(t)
        if v:
            return v
    return None

def _get_default_field_value(field):
    t = _get_field_type(field)
    if t:
        return t(field)
    return None

def _get_field_value(field, url_value):
    value_type = _get_field_type(field)
    if value_type:
        return value_type(field, url_value)
    return None

class Filter:
    def __init__(self, field, operator=None, value=None):
        self.field = field
        if value:
            self.value = value
        else:
            self.value = _get_default_field_value(field)
        if operator:
            self.operator = operator
        else:
            self.operator = self.value.available_operations[0]

    def query_dict(self):
        return self.field.bare_name() + '__' + self.operator.query, self.value.query_value()

    def url_para(self):
        return self.field.bare_name() + '-' + self.operator.query + '=' + self.value.url_vaue()

    @classmethod
    def from_request(cls, field, request):
        for o in _get_field_type(field).available_operations:
            if request.GET.has_key(field.bare_name() + "-" + o.query):
                valstr = request.GET[field.bare_name() + "-" + o.query]
                val = _get_field_value(field, valstr)
                yield Filter(field, o, val)

    def selection_value_html(self, request):
        c = Context({
            'id': self.field.bare_name() + '_' + self.operator.query,
            'field': self.field,
            'operator': self.operator,
            'default_value': self.value.value,
        })
        t = loader.get_template(self.value.selection_template)
        return t.render(c, request)

    @classmethod
    def selection_type_html(cls, field, request):
        v = _get_field_type(field)
        ff = [Filter(field, o) for o in v.available_operations]
        ss = [(f.operator, f.selection_value_html(request)) for f in ff]
        act = request.get_full_path()
        c = Context({
            'field': field,
            'operators': v.available_operations,
            'selectors': ss,
            'action': act,
        })
        t = loader.get_template(_filter_templates + 'column_selector.html')
        return t.render(c)


class FilterSet:
    def __init__(self, filters=None):
        self.filters = filters if filters else {}

    def query_dict(self):
        q = []
        for ff in self.filters.values():
            q += [f.query_dict() for f in ff]
        return dict(q)

    def url_para(self):
        return ';'.join([f.url_para for f in self.filters])

    @classmethod
    def from_request(cls, model, request):
        ff = dict([(f, list(Filter.from_request(f, request))) for f in model.fields() if _get_field_type(f)])
        return FilterSet(ff)

    @classmethod
    def can_filter(cls, field):
        return bool(_get_field_type(field))

    def render_filters(self, request):
        remove_filter_element = '<a class="rapid-remove-filter"><span class="fa fa-times"></span></a>'
        ret = ''
        kk = self.filters.keys()
        kk.sort(key=lambda f: f.name(), cmp=locale.strcoll)
        for field in kk:
            ret += '<div class="rapid-field-filters %s %s">%s\n' % ('visible' if self.filters[field] else 'hidden',
                                                                    field.bare_name(), field.name().capitalize())
            for f in self.filters[field]:
                ret += '<div>' + f.selection_value_html(request) + remove_filter_element + '</div>\n'
            ret += '</div>'
        return ret

    def render_selectors(self, request):
        ret = ''
        kk = self.filters.keys()
        kk.sort(key=lambda f: f.name(), cmp=locale.strcoll)
        for field in kk:
            ret += '<div class="rapid-filter-selection %s hidden">\n' % field.bare_name()
            ret += Filter.selection_type_html(field, request)
            ret += '</div>\n'
        return ret

    def filters_url(self):
        pass

    def has_filters(self):
        for k in self.filters.keys():
            if self.filters[k]:
                return True
        return False