import datetime

import marshmallow
from flask import current_app as app, render_template, request
from flask.json import jsonify
from flask_sqlalchemy import Pagination
from marshmallow import fields, fields as f, validate as v
from teal import query
from teal.cache import cache
from teal.resource import View

from ereuse_devicehub import auth
from ereuse_devicehub.db import db
from ereuse_devicehub.resources import search
from ereuse_devicehub.resources.device.models import Component, Computer, Device, Manufacturer
from ereuse_devicehub.resources.device.search import DeviceSearch
from ereuse_devicehub.resources.event.models import Rate
from ereuse_devicehub.resources.lot.models import Lot, LotDevice
from ereuse_devicehub.resources.tag.model import Tag


class OfType(f.Str):
    def __init__(self, column: db.Column, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.column = column

    def _deserialize(self, value, attr, data):
        v = super()._deserialize(value, attr, data)
        return self.column.in_(app.resources[v].subresources_types)


class RateQ(query.Query):
    rating = query.Between(Rate.rating, f.Float())
    appearance = query.Between(Rate.appearance, f.Float())
    functionality = query.Between(Rate.functionality, f.Float())


class TagQ(query.Query):
    id = query.Or(query.ILike(Tag.id), required=True)
    org = query.ILike(Tag.org)


class LotQ(query.Query):
    id = query.Or(query.QueryField(Lot.descendantsq, fields.UUID()))


class Filters(query.Query):
    _parent = Computer.__table__.alias()
    _device_inside_lot = (Device.id == LotDevice.device_id) & (Lot.id == LotDevice.lot_id)
    _parent_device_in_lot = (Device.id == Component.id) & (Component.parent_id == _parent.c.id) \
                            & (_parent.c.id == LotDevice.device_id) & (Lot.id == LotDevice.lot_id)

    type = query.Or(OfType(Device.type))
    model = query.ILike(Device.model)
    manufacturer = query.ILike(Device.manufacturer)
    serialNumber = query.ILike(Device.serial_number)
    rating = query.Join(Device.id == Rate.device_id, RateQ)
    tag = query.Join(Device.id == Tag.device_id, TagQ)
    # todo This part of the query is really slow
    # And forces usage of distinct, as it returns many rows
    # due to having multiple paths to the same
    lot = query.Join(_device_inside_lot | _parent_device_in_lot, LotQ)


class Sorting(query.Sort):
    id = query.SortField(Device.id)
    created = query.SortField(Device.created)


class DeviceView(View):
    class FindArgs(marshmallow.Schema):
        search = f.Raw()
        filter = f.Nested(Filters, missing=[])
        sort = f.Nested(Sorting, missing=[Device.id.asc()])
        page = f.Integer(validate=v.Range(min=1), missing=1)

    def get(self, id):
        """
        Devices view
        ---
        description: Gets a device or multiple devices.
        parameters:
          - name: id
            type: integer
            in: path
            description: The identifier of the device.
        responses:
          200:
            description: The device or devices.
        """
        # Majority of code is from teal
        if id:
            response = self.one(id)
        else:
            args = self.QUERY_PARSER.parse(self.find_args,
                                           request,
                                           locations=('querystring',))
            # todo not-nice way of de-parsing what webargs parser
            # does when sees that an argument is like an int, etc
            # when solving this, change too the Query.search to Str
            if args.get('search', False):
                args['search'] = str(args['search'])
            response = self.find(args)
        return response

    def one(self, id: int):
        """Gets one device."""
        if not request.authorization:
            return self.one_public(id)
        else:
            return self.one_private(id)

    def one_public(self, id: int):
        device = Device.query.filter_by(id=id).one()
        return render_template('devices/layout.html', device=device)

    @auth.Auth.requires_auth
    def one_private(self, id: int):
        device = Device.query.filter_by(id=id).one()
        return self.schema.jsonify(device)

    @auth.Auth.requires_auth
    def find(self, args: dict):
        """Gets many devices."""
        search_p = args.get('search', None)
        query = Device.query.distinct()  # todo we should not force to do this if the query is ok
        if search_p:
            properties = DeviceSearch.properties
            tags = DeviceSearch.tags
            query = query.join(DeviceSearch).filter(
                search.Search.match(properties, search_p) | search.Search.match(tags, search_p)
            ).order_by(
                search.Search.rank(properties, search_p) + search.Search.rank(tags, search_p)
            )
        query = query.filter(*args['filter']).order_by(*args['sort'])
        devices = query.paginate(page=args['page'], per_page=30)  # type: Pagination
        ret = {
            'items': self.schema.dump(devices.items, many=True, nested=1),
            # todo pagination should be in Header like github
            # https://developer.github.com/v3/guides/traversing-with-pagination/
            'pagination': {
                'page': devices.page,
                'perPage': devices.per_page,
                'total': devices.total,
                'previous': devices.prev_num,
                'next': devices.next_num
            },
            'url': request.path
        }
        return jsonify(ret)


class ManufacturerView(View):
    class FindArgs(marshmallow.Schema):
        search = marshmallow.fields.Str(required=True,
                                        # Disallow like operators
                                        validate=lambda x: '%' not in x and '_' not in x)

    @cache(datetime.timedelta(days=1))
    def find(self, args: dict):
        search = args['search']
        manufacturers = Manufacturer.query \
            .filter(Manufacturer.name.ilike(search + '%')) \
            .paginate(page=1, per_page=6)  # type: Pagination
        return jsonify(
            items=app.resources[Manufacturer.t].schema.dump(
                manufacturers.items,
                many=True,
                nested=1
            )
        )