import math
from datetime import datetime, time, timedelta

from pytz import UTC, timezone

from odoo import _, api, fields, models
from odoo.exceptions import UserError


def float_to_time(f):
    decimal, integer = math.modf(f)
    return "{}:{}".format(
        str(int(integer)).zfill(2), str(int(round(decimal * 60))).zfill(2)
    )


def floatime_to_hour_minute(f):
    decimal, integer = math.modf(f)
    return int(integer), int(round(decimal * 60))


def get_first_day_of_week():
    today = datetime.now()
    return (datetime.now() - timedelta(days=today.weekday())).date()


class TaskType(models.Model):
    _name = "beesdoo.shift.type"
    _description = "beesdoo.shift.type"

    name = fields.Char()
    description = fields.Text()
    active = fields.Boolean(default=True)


class DayNumber(models.Model):
    _name = "beesdoo.shift.daynumber"
    _description = "beesdoo.shift.daynumber"

    _order = "number asc"

    name = fields.Char()
    number = fields.Integer(
        "Day Number",
        help="From 1 to N, When you will instanciate your planning, Day 1 "
        "will be the start date of the instance, Day 2 the second, "
        "etc...",
    )
    active = fields.Boolean(default=True)


class Planning(models.Model):
    _name = "beesdoo.shift.planning"
    _description = "beesdoo.shift.planning"
    _order = "sequence asc"

    sequence = fields.Integer()
    name = fields.Char()
    task_template_ids = fields.One2many(
        "beesdoo.shift.template", "planning_id"
    )

    @api.model
    def _get_next_planning(self, sequence):
        next_planning = self.search([("sequence", ">", sequence)])
        if not next_planning:
            return self.search([])[0]
        return next_planning[0]

    @api.multi
    def _get_next_planning_date(self, date):
        self.ensure_one()
        nb_of_day = max(self.task_template_ids.mapped("day_nb_id.number"))
        return date + timedelta(days=nb_of_day)

    @api.model
    def _generate_next_planning(self):
        config = self.env["ir.config_parameter"].sudo()
        last_seq = int(config.get_param("last_planning_seq", 0))
        date = fields.Date.from_string(
            config.get_param("next_planning_date", 0)
        )

        planning = self._get_next_planning(last_seq)
        planning = planning.with_context(visualize_date=date)
        planning.task_template_ids._generate_task_day()

        next_date = planning._get_next_planning_date(date)
        config.set_param("last_planning_seq", planning.sequence)
        config.set_param("next_planning_date", next_date)


class TaskTemplate(models.Model):
    _name = "beesdoo.shift.template"
    _description = "beesdoo.shift.template"
    _order = "start_time"

    name = fields.Char(required=True)
    planning_id = fields.Many2one("beesdoo.shift.planning", required=True)
    day_nb_id = fields.Many2one(
        "beesdoo.shift.daynumber", string="Day", required=True
    )
    task_type_id = fields.Many2one("beesdoo.shift.type", string="Type")
    # FIXME removed because beesdoo.shift.sheet is from another module.
    # attendance_sheet_id = fields.Many2one('beesdoo.shift.sheet', string="Attendance Sheet")  # noqa
    start_time = fields.Float(required=True)
    end_time = fields.Float(required=True)
    super_coop_id = fields.Many2one(
        "res.users",
        string="Super Cooperative",
        domain=[("partner_id.super", "=", True)],
    )

    duration = fields.Float(help="Duration in Hour")
    worker_nb = fields.Integer(
        string="Number of worker",
        help="Max number of worker for this task",
        default=1,
    )
    worker_ids = fields.Many2many(
        "res.partner",
        string="Recurrent worker assigned",
        domain=[("is_worker", "=", True)],
    )
    remaining_worker = fields.Integer(
        compute="_compute_remaining", store=True, string="Remaining Place"
    )
    active = fields.Boolean(default=True)
    # For Kanban View Only
    color = fields.Integer("Color Index")
    worker_name = fields.Char(compute="_compute_worker_name")
    # For calendar View
    start_date = fields.Datetime(
        compute="_compute_fake_date", search="_search_dummy"
    )
    end_date = fields.Datetime(
        compute="_compute_fake_date", search="_search_dummy"
    )

    def _get_utc_date(self, day, hour, minute):
        """Combine day number, hours and minutes to save
        corresponding UTC datetime in database.
        """
        context_tz = timezone(self._context.get("tz") or self.env.user.tz)
        day_local_time = datetime.combine(day, time(hour=hour, minute=minute))
        day_local_time = context_tz.localize(day_local_time)
        day_utc_time = day_local_time.astimezone(UTC)
        # Return naïve datetime so as to be saved in database
        return day_utc_time.replace(tzinfo=None)

    @api.depends("start_time", "end_time")
    def _compute_fake_date(self):
        today = self._context.get("visualize_date", get_first_day_of_week())
        for rec in self:
            # Find the day of this task template 'rec'.
            day = today + timedelta(days=rec.day_nb_id.number - 1)
            # Compute the beginning and ending time according to the
            # context timezone.
            h_begin, m_begin = floatime_to_hour_minute(rec.start_time)
            h_end, m_end = floatime_to_hour_minute(rec.end_time)
            rec.start_date = self._get_utc_date(day, h_begin, m_begin)
            rec.end_date = self._get_utc_date(day, h_end, m_end)

    def _search_dummy(self, operator, value):
        return []

    @api.depends("worker_ids", "worker_nb")
    def _compute_remaining(self):
        for rec in self:
            rec.remaining_worker = rec.worker_nb - len(rec.worker_ids)

    @api.depends("worker_ids")
    def _compute_worker_name(self):
        for rec in self:
            rec.worker_name = ",".join(rec.worker_ids.mapped("display_name"))

    @api.constrains("worker_nb", "worker_ids")
    def _nb_worker_max(self):
        for rec in self:
            if len(rec.worker_ids) > rec.worker_nb:
                raise UserError(
                    _(
                        "You cannot assign more workers than the maximal "
                        "number defined on template. "
                    )
                )

    @api.onchange("start_time", "end_time")
    def _get_duration(self):
        if self.start_time and self.end_time:
            self.duration = self.end_time - self.start_time

    @api.onchange("duration")
    def _set_duration(self):
        if self.start_time:
            self.end_time = self.start_time + self.duration

    def _generate_task_day(self):
        tasks = self.env["beesdoo.shift.shift"]
        for rec in self:
            for i in range(0, rec.worker_nb):
                worker_id = (
                    rec.worker_ids[i] if len(rec.worker_ids) > i else False
                )
                # remove worker in holiday and temporary exempted
                if worker_id and worker_id.cooperative_status_ids:
                    status = worker_id.cooperative_status_ids[0]
                    if (
                        status.holiday_start_time
                        and status.holiday_end_time
                        and status.holiday_start_time <= rec.start_date.date()
                        and status.holiday_end_time >= rec.end_date.date()
                    ):
                        worker_id = False
                    if (
                        status.temporary_exempt_start_date
                        and status.temporary_exempt_end_date
                        and status.temporary_exempt_start_date
                        <= rec.start_date.date()
                        and status.temporary_exempt_end_date
                        >= rec.end_date.date()
                    ):
                        worker_id = False
                tasks |= tasks.create(
                    {
                        "name": "[%s] %s %s (%s - %s) [%s]"
                        % (
                            rec.start_date.date(),
                            rec.planning_id.name,
                            rec.day_nb_id.name,
                            float_to_time(rec.start_time),
                            float_to_time(rec.end_time),
                            i,
                        ),
                        "task_template_id": rec.id,
                        "task_type_id": rec.task_type_id.id,
                        "super_coop_id": rec.super_coop_id.id,
                        "worker_id": worker_id and worker_id.id or False,
                        "is_regular": True if worker_id else False,
                        "start_time": rec.start_date,
                        "end_time": rec.end_date,
                        "state": "open",
                    }
                )

        return tasks

    @api.onchange("worker_ids")
    def check_for_multiple_shifts(self):
        original_ids = {worker.id for worker in self._origin.worker_ids}

        warnings = []
        for worker in self.worker_ids:
            if worker.id not in original_ids:
                shifts = [
                    shift.name
                    for shift in worker.subscribed_shift_ids
                    if shift.id != self.id
                ]
                if shifts:
                    warnings.append(
                        worker.name
                        + _(" is already assigned to ")
                        + ", ".join(shifts)
                    )

        if warnings:
            return {
                "warning": {
                    "title": _("Warning"),
                    "message": "\n".join(warnings),
                }
            }