# -*- coding: utf-8 -*-
# Part of Odoo. See LICENSE file for full copyright and licensing details.

import datetime
import calendar

from dateutil.relativedelta import relativedelta

from odoo import _, api, fields, models
from odoo.tools.date_utils import get_timedelta


DAYS = ['sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat']
MONTHS = ['jan', 'feb', 'mar', 'apr', 'may', 'jun', 'jul', 'aug', 'sep', 'oct', 'nov', 'dec']
# Used for displaying the days and reversing selection -> integer
DAY_SELECT_VALUES = [str(i) for i in range(1, 29)] + ['last']
DAY_SELECT_SELECTION_NO_LAST = tuple(zip(DAY_SELECT_VALUES, (str(i) for i in range(1, 29))))

def _get_selection_days(self):
    return DAY_SELECT_SELECTION_NO_LAST + (("last", _("last day")),)

class AccrualPlanLevel(models.Model):
    _name = "hr.leave.accrual.level"
    _description = "Accrual Plan Level"
    _order = 'sequence asc'

    sequence = fields.Integer(
        string='sequence', compute='_compute_sequence', store=True,
        help='Sequence is generated automatically by start time delta.')
    accrual_plan_id = fields.Many2one('hr.leave.accrual.plan', "Accrual Plan", required=True)
    start_count = fields.Integer(
        "Start after",
        help="The accrual starts after a defined period from the allocation start date. This field defines the number of days, months or years after which accrual is used.", default="1")
    start_type = fields.Selection(
        [('day', 'day(s)'),
         ('month', 'month(s)'),
         ('year', 'year(s)')],
        default='day', string=" ", required=True,
        help="This field defines the unit of time after which the accrual starts.")
    is_based_on_worked_time = fields.Boolean("Based on worked time",
        help="If checked, the rate will be prorated on time off type where type is set on Working Time in the configuration.")

    # Accrue of
    added_value = fields.Float(
        "Rate", digits=(16, 5), required=True,
        help="The number of hours/days that will be incremented in the specified Time Off Type for every period")
    added_value_type = fields.Selection(
        [('days', 'Days'),
         ('hours', 'Hours')],
        default='days', required=True)
    frequency = fields.Selection([
        ('daily', 'Daily'),
        ('weekly', 'Weekly'),
        ('bimonthly', 'Twice a month'),
        ('monthly', 'Monthly'),
        ('biyearly', 'Twice a year'),
        ('yearly', 'Yearly'),
    ], default='daily', required=True, string="Frequency")
    week_day = fields.Selection([
        ('mon', 'Monday'),
        ('tue', 'Tuesday'),
        ('wed', 'Wednesday'),
        ('thu', 'Thursday'),
        ('fri', 'Friday'),
        ('sat', 'Saturday'),
        ('sun', 'Sunday'),
    ], default='mon', required=True, string="Allocation on")
    first_day = fields.Integer(default=1)
    first_day_display = fields.Selection(
        _get_selection_days, compute='_compute_days_display', inverse='_inverse_first_day_display')
    second_day = fields.Integer(default=15)
    second_day_display = fields.Selection(
        _get_selection_days, compute='_compute_days_display', inverse='_inverse_second_day_display')
    first_month_day = fields.Integer(default=1)
    first_month_day_display = fields.Selection(
        _get_selection_days, compute='_compute_days_display', inverse='_inverse_first_month_day_display')
    first_month = fields.Selection([
        ('jan', 'January'),
        ('feb', 'February'),
        ('mar', 'March'),
        ('apr', 'April'),
        ('may', 'May'),
        ('jun', 'June'),
    ], default="jan")
    second_month_day = fields.Integer(default=1)
    second_month_day_display = fields.Selection(
        _get_selection_days, compute='_compute_days_display', inverse='_inverse_second_month_day_display')
    second_month = fields.Selection([
        ('jul', 'July'),
        ('aug', 'August'),
        ('sep', 'September'),
        ('oct', 'October'),
        ('nov', 'November'),
        ('dec', 'December')
    ], default="jul")
    yearly_month = fields.Selection([
        ('jan', 'January'),
        ('feb', 'February'),
        ('mar', 'March'),
        ('apr', 'April'),
        ('may', 'May'),
        ('jun', 'June'),
        ('jul', 'July'),
        ('aug', 'August'),
        ('sep', 'September'),
        ('oct', 'October'),
        ('nov', 'November'),
        ('dec', 'December')
    ], default="jan")
    yearly_day = fields.Integer(default=1)
    yearly_day_display = fields.Selection(
        _get_selection_days, compute='_compute_days_display', inverse='_inverse_yearly_day_display')
    maximum_leave = fields.Float(
        'Limit to', required=False, default=100,
        help="Choose a cap for this accrual. 0 means no cap.")
    parent_id = fields.Many2one(
        'hr.leave.accrual.level', string="Previous Level",
        help="If this field is empty, this level is the first one.")
    action_with_unused_accruals = fields.Selection(
        [('postponed', 'Transferred to the next year'),
         ('lost', 'Lost')],
        string="At the end of the calendar year, unused accruals will be",
        default='postponed', required='True')
    postpone_max_days = fields.Integer("Maximum amount of accruals to transfer",
        help="Set a maximum of days an allocation keeps at the end of the year. 0 for no limit.")

    _sql_constraints = [
        ('check_dates',
         "CHECK( (frequency = 'daily') or"
         "(week_day IS NOT NULL AND frequency = 'weekly') or "
         "(first_day > 0 AND second_day > first_day AND first_day <= 31 AND second_day <= 31 AND frequency = 'bimonthly') or "
         "(first_day > 0 AND first_day <= 31 AND frequency = 'monthly')or "
         "(first_month_day > 0 AND first_month_day <= 31 AND second_month_day > 0 AND second_month_day <= 31 AND frequency = 'biyearly') or "
         "(yearly_day > 0 AND yearly_day <= 31 AND frequency = 'yearly'))",
         "The dates you've set up aren't correct. Please check them."),
        ('start_count_check', "CHECK( start_count >= 0 )", "You can not start an accrual in the past."),
        ('added_value_greater_than_zero', 'CHECK(added_value > 0)', 'You must give a rate greater than 0 in accrual plan levels.')
    ]

    @api.depends('start_count', 'start_type')
    def _compute_sequence(self):
        # Not 100% accurate because of odd months/years, but good enough
        start_type_multipliers = {
            'day': 1,
            'month': 30,
            'year': 365,
        }
        for level in self:
            level.sequence = level.start_count * start_type_multipliers[level.start_type]

    @api.depends('first_day', 'second_day', 'first_month_day', 'second_month_day', 'yearly_day')
    def _compute_days_display(self):
        days_select = _get_selection_days(self)
        for level in self:
            level.first_day_display = days_select[min(level.first_day - 1, 28)][0]
            level.second_day_display = days_select[min(level.second_day - 1, 28)][0]
            level.first_month_day_display = days_select[min(level.first_month_day - 1, 28)][0]
            level.second_month_day_display = days_select[min(level.second_month_day - 1, 28)][0]
            level.yearly_day_display = days_select[min(level.yearly_day - 1, 28)][0]

    def _inverse_first_day_display(self):
        for level in self:
            if level.first_day_display == 'last':
                level.first_day = 31
            else:
                level.first_day = DAY_SELECT_VALUES.index(level.first_day_display) + 1

    def _inverse_second_day_display(self):
        for level in self:
            if level.second_day_display == 'last':
                level.second_day = 31
            else:
                level.second_day = DAY_SELECT_VALUES.index(level.second_day_display) + 1

    def _inverse_first_month_day_display(self):
        for level in self:
            if level.first_month_day_display == 'last':
                level.first_month_day = 31
            else:
                level.first_month_day = DAY_SELECT_VALUES.index(level.first_month_day_display) + 1

    def _inverse_second_month_day_display(self):
        for level in self:
            if level.second_month_day_display == 'last':
                level.second_month_day = 31
            else:
                level.second_month_day = DAY_SELECT_VALUES.index(level.second_month_day_display) + 1

    def _inverse_yearly_day_display(self):
        for level in self:
            if level.yearly_day_display == 'last':
                level.yearly_day = 31
            else:
                level.yearly_day = DAY_SELECT_VALUES.index(level.yearly_day_display) + 1

    def _get_next_date(self, last_call):
        """
        Returns the next date with the given last call
        """
        self.ensure_one()
        if self.frequency == 'daily':
            return last_call + relativedelta(days=1)
        elif self.frequency == 'weekly':
            daynames = ['mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun']
            weekday = daynames.index(self.week_day)
            return last_call + relativedelta(days=1, weekday=weekday)
        elif self.frequency == 'bimonthly':
            first_date = last_call + relativedelta(day=self.first_day)
            second_date = last_call + relativedelta(day=self.second_day)
            if last_call < first_date:
                return first_date
            elif last_call < second_date:
                return second_date
            else:
                return last_call + relativedelta(months=1, day=self.first_day)
        elif self.frequency == 'monthly':
            date = last_call + relativedelta(day=self.first_day)
            if last_call < date:
                return date
            else:
                return last_call + relativedelta(months=1, day=self.first_day)
        elif self.frequency == 'biyearly':
            first_month = MONTHS.index(self.first_month) + 1
            second_month = MONTHS.index(self.second_month) + 1
            first_date = last_call + relativedelta(month=first_month, day=self.first_month_day)
            second_date = last_call + relativedelta(month=second_month, day=self.second_month_day)
            if last_call < first_date:
                return first_date
            elif last_call < second_date:
                return second_date
            else:
                return last_call + relativedelta(years=1, month=first_month, day=self.first_month_day)
        elif self.frequency == 'yearly':
            month = MONTHS.index(self.yearly_month) + 1
            date = last_call + relativedelta(month=month, day=self.yearly_day)
            if last_call < date:
                return date
            else:
                return last_call + relativedelta(years=1, month=month, day=self.yearly_day)
        else:
            return False

    def _get_previous_date(self, last_call):
        """
        Returns the date a potential previous call would have been at
        For example if you have a monthly level giving 16/02 would return 01/02
        Contrary to `_get_next_date` this function will return the 01/02 if that date is given
        """
        self.ensure_one()
        if self.frequency == 'daily':
            return last_call
        elif self.frequency == 'weekly':
            daynames = ['mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun']
            weekday = daynames.index(self.week_day)
            return last_call + relativedelta(days=-6, weekday=weekday)
        elif self.frequency == 'bimonthly':
            second_date = last_call + relativedelta(day=self.second_day)
            first_date = last_call + relativedelta(day=self.first_day)
            if last_call >= second_date:
                return second_date
            elif last_call >= first_date:
                return first_date
            else:
                return last_call + relativedelta(months=-1, day=self.second_day)
        elif self.frequency == 'monthly':
            date = last_call + relativedelta(day=self.first_day)
            if last_call >= date:
                return date
            else:
                return last_call + relativedelta(months=-1, day=self.first_day)
        elif self.frequency == 'biyearly':
            first_month = MONTHS.index(self.first_month) + 1
            second_month = MONTHS.index(self.second_month) + 1
            first_date = last_call + relativedelta(month=first_month, day=self.first_month_day)
            second_date = last_call + relativedelta(month=second_month, day=self.second_month_day)
            if last_call >= second_date:
                return second_date
            elif last_call >= first_date:
                return first_date
            else:
                return last_call + relativedelta(years=-1, month=second_month, day=self.second_month_day)
        elif self.frequency == 'yearly':
            month = MONTHS.index(self.yearly_month) + 1
            year_date = last_call + relativedelta(month=month, day=self.yearly_day)
            if last_call >= year_date:
                return year_date
            else:
                return last_call + relativedelta(years=-1, month=month, day=self.yearly_day)
        else:
            return False