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

# Copyright (c) 2005-2006 Axelor SARL. (http://www.axelor.com)

import logging
import math
from datetime import timedelta
from werkzeug import url_encode

from odoo import api, fields, models
from odoo.exceptions import UserError, AccessError, ValidationError
from openerp.tools import float_compare
from odoo.tools.translate import _

_logger = logging.getLogger(__name__)


HOURS_PER_DAY = 8


class HolidaysType(models.Model):

    _name = "hr.holidays.status"
    _description = "Leave Type"

    name = fields.Char('Leave Type', required=True, translate=True)
    categ_id = fields.Many2one('calendar.event.type', string='Meeting Type',
        help='Once a leave is validated, Odoo will create a corresponding meeting of this type in the calendar.')
    color_name = fields.Selection([
        ('red', 'Red'),
        ('blue', 'Blue'),
        ('lightgreen', 'Light Green'),
        ('lightblue', 'Light Blue'),
        ('lightyellow', 'Light Yellow'),
        ('magenta', 'Magenta'),
        ('lightcyan', 'Light Cyan'),
        ('black', 'Black'),
        ('lightpink', 'Light Pink'),
        ('brown', 'Brown'),
        ('violet', 'Violet'),
        ('lightcoral', 'Light Coral'),
        ('lightsalmon', 'Light Salmon'),
        ('lavender', 'Lavender'),
        ('wheat', 'Wheat'),
        ('ivory', 'Ivory')], string='Color in Report', required=True, default='red',
        help='This color will be used in the leaves summary located in Reporting > Leaves by Department.')
    limit = fields.Boolean('Allow to Override Limit',
        help='If you select this check box, the system allows the employees to take more leaves '
             'than the available ones for this type and will not take them into account for the '
             '"Remaining Legal Leaves" defined on the employee form.')
    active = fields.Boolean('Active', default=True,
        help="If the active field is set to false, it will allow you to hide the leave type without removing it.")

    max_leaves = fields.Float(compute='_compute_leaves', string='Maximum Allowed',
        help='This value is given by the sum of all holidays requests with a positive value.')
    leaves_taken = fields.Float(compute='_compute_leaves', string='Leaves Already Taken',
        help='This value is given by the sum of all holidays requests with a negative value.')
    remaining_leaves = fields.Float(compute='_compute_leaves', string='Remaining Leaves',
        help='Maximum Leaves Allowed - Leaves Already Taken')
    virtual_remaining_leaves = fields.Float(compute='_compute_leaves', string='Virtual Remaining Leaves',
        help='Maximum Leaves Allowed - Leaves Already Taken - Leaves Waiting Approval')

    double_validation = fields.Boolean(string='Apply Double Validation',
        help="When selected, the Allocation/Leave Requests for this type require a second validation to be approved.")
    company_id = fields.Many2one('res.company', string='Company')

    @api.multi
    def get_days(self, employee_id):
        # need to use `dict` constructor to create a dict per id
        result = dict((id, dict(max_leaves=0, leaves_taken=0, remaining_leaves=0, virtual_remaining_leaves=0)) for id in self.ids)

        holidays = self.env['hr.holidays'].search([
            ('employee_id', '=', employee_id),
            ('state', 'in', ['confirm', 'validate1', 'validate']),
            ('holiday_status_id', 'in', self.ids)
        ])

        for holiday in holidays:
            status_dict = result[holiday.holiday_status_id.id]
            if holiday.type == 'add':
                if holiday.state == 'validate':
                    # note: add only validated allocation even for the virtual
                    # count; otherwise pending then refused allocation allow
                    # the employee to create more leaves than possible
                    status_dict['virtual_remaining_leaves'] += holiday.number_of_days_temp
                    status_dict['max_leaves'] += holiday.number_of_days_temp
                    status_dict['remaining_leaves'] += holiday.number_of_days_temp
            elif holiday.type == 'remove':  # number of days is negative
                status_dict['virtual_remaining_leaves'] -= holiday.number_of_days_temp
                if holiday.state == 'validate':
                    status_dict['leaves_taken'] += holiday.number_of_days_temp
                    status_dict['remaining_leaves'] -= holiday.number_of_days_temp
        return result

    @api.multi
    def _compute_leaves(self):
        data_days = {}
        if 'employee_id' in self._context:
            employee_id = self._context['employee_id']
        else:
            employee_id = self.env['hr.employee'].search([('user_id', '=', self.env.user.id)], limit=1).id

        if employee_id:
            data_days = self.get_days(employee_id)

        for holiday_status in self:
            result = data_days.get(holiday_status.id, {})
            holiday_status.max_leaves = result.get('max_leaves', 0)
            holiday_status.leaves_taken = result.get('leaves_taken', 0)
            holiday_status.remaining_leaves = result.get('remaining_leaves', 0)
            holiday_status.virtual_remaining_leaves = result.get('virtual_remaining_leaves', 0)

    @api.multi
    def name_get(self):
        if not self._context.get('employee_id'):
            # leave counts is based on employee_id, would be inaccurate if not based on correct employee
            return super(HolidaysType, self).name_get()
        res = []
        for record in self:
            name = record.name
            if not record.limit:
                name = "%(name)s (%(count)s)" % {
                    'name': name,
                    'count': _('%g remaining out of %g') % (record.virtual_remaining_leaves or 0.0, record.max_leaves or 0.0)
                }
            res.append((record.id, name))
        return res

    @api.model
    def _search(self, args, offset=0, limit=None, order=None, count=False, access_rights_uid=None):
        """ Override _search to order the results, according to some employee.
        The order is the following

         - limit (limited leaves first, such as Legal Leaves)
         - virtual remaining leaves (higher the better, so using reverse on sorted)

        This override is necessary because those fields are not stored and depends
        on an employee_id given in context. This sort will be done when there
        is an employee_id in context and that no other order has been given
        to the method.
        """
        leave_ids = super(HolidaysType, self)._search(args, offset=offset, limit=limit, order=order, count=count, access_rights_uid=access_rights_uid)
        if not count and not order and self._context.get('employee_id'):
            leaves = self.browse(leave_ids)
            sort_key = lambda l: (not l.limit, l.virtual_remaining_leaves)
            return map(int, leaves.sorted(key=sort_key, reverse=True))
        return leave_ids


class Holidays(models.Model):

    _name = "hr.holidays"
    _description = "Leave"
    _order = "type desc, date_from desc"
    _inherit = ['mail.thread', 'ir.needaction_mixin']

    def _default_employee(self):
        return self.env.context.get('default_employee_id') or self.env['hr.employee'].search([('user_id', '=', self.env.uid)], limit=1)

    name = fields.Char('Description')
    state = fields.Selection([
        ('draft', 'To Submit'),
        ('cancel', 'Cancelled'),
        ('confirm', 'To Approve'),
        ('refuse', 'Refused'),
        ('validate1', 'Second Approval'),
        ('validate', 'Approved')
        ], string='Status', readonly=True, track_visibility='onchange', copy=False, default='confirm',
            help="The status is set to 'To Submit', when a holiday request is created." +
            "\nThe status is 'To Approve', when holiday request is confirmed by user." +
            "\nThe status is 'Refused', when holiday request is refused by manager." +
            "\nThe status is 'Approved', when holiday request is approved by manager.")
    payslip_status = fields.Boolean('Reported in last payslips',
        help='Green this button when the leave has been taken into account in the payslip.')
    report_note = fields.Text('HR Comments')
    user_id = fields.Many2one('res.users', string='User', related='employee_id.user_id', related_sudo=True, store=True, default=lambda self: self.env.uid, readonly=True)
    date_from = fields.Datetime('Start Date', readonly=True, index=True, copy=False,
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]})
    date_to = fields.Datetime('End Date', readonly=True, copy=False,
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]})
    holiday_status_id = fields.Many2one("hr.holidays.status", string="Leave Type", required=True, readonly=True,
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]})
    employee_id = fields.Many2one('hr.employee', string='Employee', index=True, readonly=True,
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]}, default=_default_employee)
    manager_id = fields.Many2one('hr.employee', string='First Approval', readonly=True, copy=False,
        help='This area is automatically filled by the user who validate the leave')
    notes = fields.Text('Reasons', readonly=True, states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]})
    number_of_days_temp = fields.Float('Allocation', readonly=True, copy=False,
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]})
    number_of_days = fields.Float('Number of Days', compute='_compute_number_of_days', store=True)
    meeting_id = fields.Many2one('calendar.event', string='Meeting')
    type = fields.Selection([
            ('remove', 'Leave Request'),
            ('add', 'Allocation Request')
        ], string='Request Type', required=True, readonly=True, index=True, default='remove',
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]},
        help="Choose 'Leave Request' if someone wants to take an off-day. "
             "\nChoose 'Allocation Request' if you want to increase the number of leaves available for someone")
    parent_id = fields.Many2one('hr.holidays', string='Parent')
    linked_request_ids = fields.One2many('hr.holidays', 'parent_id', string='Linked Requests')
    department_id = fields.Many2one('hr.department', related='employee_id.department_id', string='Department', readonly=True, store=True)
    category_id = fields.Many2one('hr.employee.category', string='Employee Tag', readonly=True,
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]}, help='Category of Employee')
    holiday_type = fields.Selection([
        ('employee', 'By Employee'),
        ('category', 'By Employee Tag')
    ], string='Allocation Mode', readonly=True, required=True, default='employee',
        states={'draft': [('readonly', False)], 'confirm': [('readonly', False)]},
        help='By Employee: Allocation/Request for individual Employee, By Employee Tag: Allocation/Request for group of employees in category')
    manager_id2 = fields.Many2one('hr.employee', string='Second Approval', readonly=True, copy=False,
        help='This area is automaticly filled by the user who validate the leave with second level (If Leave type need second validation)')
    double_validation = fields.Boolean('Apply Double Validation', related='holiday_status_id.double_validation')
    can_reset = fields.Boolean('Can reset', compute='_compute_can_reset')

    @api.multi
    @api.depends('number_of_days_temp', 'type')
    def _compute_number_of_days(self):
        for holiday in self:
            if holiday.type == 'remove':
                holiday.number_of_days = -holiday.number_of_days_temp
            else:
                holiday.number_of_days = holiday.number_of_days_temp

    @api.multi
    def _compute_can_reset(self):
        """ User can reset a leave request if it is its own leave request
            or if he is an Hr Manager.
        """
        user = self.env.user
        group_hr_manager = self.env.ref('hr_holidays.group_hr_holidays_manager')
        for holiday in self:
            if group_hr_manager in user.groups_id or holiday.employee_id and holiday.employee_id.user_id == user:
                holiday.can_reset = True

    @api.constrains('date_from', 'date_to')
    def _check_date(self):
        for holiday in self:
            domain = [
                ('date_from', '<=', holiday.date_to),
                ('date_to', '>=', holiday.date_from),
                ('employee_id', '=', holiday.employee_id.id),
                ('id', '!=', holiday.id),
                ('type', '=', holiday.type),
                ('state', 'not in', ['cancel', 'refuse']),
            ]
            nholidays = self.search_count(domain)
            if nholidays:
                raise ValidationError(_('You can not have 2 leaves that overlaps on same day!'))

    @api.constrains('state', 'number_of_days_temp', 'holiday_status_id')
    def _check_holidays(self):
        for holiday in self:
            if holiday.holiday_type != 'employee' or holiday.type != 'remove' or not holiday.employee_id or holiday.holiday_status_id.limit:
                continue
            leave_days = holiday.holiday_status_id.get_days(holiday.employee_id.id)[holiday.holiday_status_id.id]
            if float_compare(leave_days['remaining_leaves'], 0, precision_digits=2) == -1 or \
              float_compare(leave_days['virtual_remaining_leaves'], 0, precision_digits=2) == -1:
                raise ValidationError(_('The number of remaining leaves is not sufficient for this leave type.\n'
                                        'Please verify also the leaves waiting for validation.'))

    _sql_constraints = [
        ('type_value', "CHECK( (holiday_type='employee' AND employee_id IS NOT NULL) or (holiday_type='category' AND category_id IS NOT NULL))",
         "The employee or employee category of this request is missing. Please make sure that your user login is linked to an employee."),
        ('date_check2', "CHECK ( (type='add') OR (date_from <= date_to))", "The start date must be anterior to the end date."),
        ('date_check', "CHECK ( number_of_days_temp >= 0 )", "The number of days must be greater than 0."),
    ]

    @api.onchange('holiday_type')
    def _onchange_type(self):
        if self.holiday_type == 'employee' and not self.employee_id:
            self.employee_id = self.env['hr.employee'].search([('user_id', '=', self.env.uid)], limit=1)
        elif self.holiday_type != 'employee':
            self.employee_id = None

    @api.onchange('employee_id')
    def _onchange_employee(self):
        self.department_id = self.employee_id.department_id

    def _get_number_of_days(self, date_from, date_to, employee_id):
        """ Returns a float equals to the timedelta between two dates given as string."""
        from_dt = fields.Datetime.from_string(date_from)
        to_dt = fields.Datetime.from_string(date_to)

        if employee_id:
            employee = self.env['hr.employee'].browse(employee_id)
            resource = employee.resource_id.sudo()
            if resource and resource.calendar_id:
                hours = resource.calendar_id.get_working_hours(from_dt, to_dt, resource_id=resource.id, compute_leaves=True)
                uom_hour = resource.calendar_id.uom_id
                uom_day = self.env.ref('product.product_uom_day')
                if uom_hour and uom_day:
                    return uom_hour._compute_quantity(hours, uom_day)

        time_delta = to_dt - from_dt
        return math.ceil(time_delta.days + float(time_delta.seconds) / 86400)

    @api.onchange('date_from')
    def _onchange_date_from(self):
        """ If there are no date set for date_to, automatically set one 8 hours later than
            the date_from. Also update the number_of_days.
        """
        date_from = self.date_from
        date_to = self.date_to

        # No date_to set so far: automatically compute one 8 hours later
        if date_from and not date_to:
            date_to_with_delta = fields.Datetime.from_string(date_from) + timedelta(hours=HOURS_PER_DAY)
            self.date_to = str(date_to_with_delta)

        # Compute and update the number of days
        if (date_to and date_from) and (date_from <= date_to):
            self.number_of_days_temp = self._get_number_of_days(date_from, date_to, self.employee_id.id)
        else:
            self.number_of_days_temp = 0

    @api.onchange('date_to')
    def _onchange_date_to(self):
        """ Update the number_of_days. """
        date_from = self.date_from
        date_to = self.date_to

        # Compute and update the number of days
        if (date_to and date_from) and (date_from <= date_to):
            self.number_of_days_temp = self._get_number_of_days(date_from, date_to, self.employee_id.id)
        else:
            self.number_of_days_temp = 0

    ####################################################
    # ORM Overrides methods
    ####################################################

    @api.multi
    def name_get(self):
        res = []
        for leave in self:
            res.append((leave.id, _("%s on %s : %.2f day(s)") % (leave.employee_id.name or leave.category_id.name, leave.holiday_status_id.name, leave.number_of_days_temp)))
        return res

    def _check_state_access_right(self, vals):
        if vals.get('state') and vals['state'] not in ['draft', 'confirm', 'cancel'] and not self.env['res.users'].has_group('hr_holidays.group_hr_holidays_user'):
            return False
        return True

    @api.multi
    def add_follower(self, employee_id):
        employee = self.env['hr.employee'].browse(employee_id)
        if employee.user_id:
            self.message_subscribe_users(user_ids=employee.user_id.ids)

    @api.model
    def create(self, values):
        """ Override to avoid automatic logging of creation """
        employee_id = values.get('employee_id', False)
        if not self._check_state_access_right(values):
            raise AccessError(_('You cannot set a leave request as \'%s\'. Contact a human resource manager.') % values.get('state'))
        if not values.get('department_id'):
            values.update({'department_id': self.env['hr.employee'].browse(employee_id).department_id.id})
        holiday = super(Holidays, self.with_context(mail_create_nolog=True, mail_create_nosubscribe=True)).create(values)
        holiday.add_follower(employee_id)
        return holiday

    @api.multi
    def write(self, values):
        employee_id = values.get('employee_id', False)
        if not self._check_state_access_right(values):
            raise AccessError(_('You cannot set a leave request as \'%s\'. Contact a human resource manager.') % values.get('state'))
        result = super(Holidays, self).write(values)
        self.add_follower(employee_id)
        return result

    @api.multi
    def unlink(self):
        for holiday in self.filtered(lambda holiday: holiday.state not in ['draft', 'cancel', 'confirm']):
            raise UserError(_('You cannot delete a leave which is in %s state.') % (holiday.state,))
        return super(Holidays, self).unlink()

    ####################################################
    # Business methods
    ####################################################

    @api.multi
    def _create_resource_leave(self):
        """ This method will create entry in resource calendar leave object at the time of holidays validated """
        for leave in self:
            self.env['resource.calendar.leaves'].create({
                'name': leave.name,
                'date_from': leave.date_from,
                'holiday_id': leave.id,
                'date_to': leave.date_to,
                'resource_id': leave.employee_id.resource_id.id,
                'calendar_id': leave.employee_id.resource_id.calendar_id.id
            })
        return True

    @api.multi
    def _remove_resource_leave(self):
        """ This method will create entry in resource calendar leave object at the time of holidays cancel/removed """
        return self.env['resource.calendar.leaves'].search([('holiday_id', 'in', self.ids)]).unlink()

    @api.multi
    def action_draft(self):
        for holiday in self:
            if not holiday.can_reset:
                raise UserError(_('Only an HR Manager or the concerned employee can reset to draft.'))
            if holiday.state not in ['confirm', 'refuse']:
                raise UserError(_('Leave request state must be "Refused" or "To Approve" in order to reset to Draft.'))
            holiday.write({
                'state': 'draft',
                'manager_id': False,
                'manager_id2': False,
            })
            linked_requests = holiday.mapped('linked_request_ids')
            for linked_request in linked_requests:
                linked_request.action_draft()
            linked_requests.unlink()
        return True

    @api.multi
    def action_confirm(self):
        if self.filtered(lambda holiday: holiday.state != 'draft'):
            raise UserError(_('Leave request must be in Draft state ("To Submit") in order to confirm it.'))
        return self.write({'state': 'confirm'})

    @api.multi
    def action_approve(self):
        # if double_validation: this method is the first approval approval
        # if not double_validation: this method calls action_validate() below
        if not self.env.user.has_group('hr_holidays.group_hr_holidays_user'):
            raise UserError(_('Only an HR Officer or Manager can approve leave requests.'))

        manager = self.env['hr.employee'].search([('user_id', '=', self.env.uid)], limit=1)
        for holiday in self:
            if holiday.state != 'confirm':
                raise UserError(_('Leave request must be confirmed ("To Approve") in order to approve it.'))

            if holiday.double_validation:
                return holiday.write({'state': 'validate1', 'manager_id': manager.id if manager else False})
            else:
                holiday.action_validate()

    @api.multi
    def _prepare_create_by_category(self, employee):
        self.ensure_one()
        values = {
            'name': self.name,
            'type': self.type,
            'holiday_type': 'employee',
            'holiday_status_id': self.holiday_status_id.id,
            'date_from': self.date_from,
            'date_to': self.date_to,
            'notes': self.notes,
            'number_of_days_temp': self.number_of_days_temp,
            'parent_id': self.id,
            'employee_id': employee.id
        }
        return values

    @api.multi
    def action_validate(self):
        if not self.env.user.has_group('hr_holidays.group_hr_holidays_user'):
            raise UserError(_('Only an HR Officer or Manager can approve leave requests.'))

        manager = self.env['hr.employee'].search([('user_id', '=', self.env.uid)], limit=1)
        for holiday in self:
            if holiday.state not in ['confirm', 'validate1']:
                raise UserError(_('Leave request must be confirmed in order to approve it.'))
            if holiday.state == 'validate1' and not holiday.env.user.has_group('hr_holidays.group_hr_holidays_manager'):
                raise UserError(_('Only an HR Manager can apply the second approval on leave requests.'))

            holiday.write({'state': 'validate'})
            if holiday.double_validation:
                holiday.write({'manager_id2': manager.id})
            else:
                holiday.write({'manager_id': manager.id})
            if holiday.holiday_type == 'employee' and holiday.type == 'remove':
                meeting_values = {
                    'name': holiday.display_name,
                    'categ_ids': [(6, 0, [holiday.holiday_status_id.categ_id.id])] if holiday.holiday_status_id.categ_id else [],
                    'duration': holiday.number_of_days_temp * HOURS_PER_DAY,
                    'description': holiday.notes,
                    'user_id': holiday.user_id.id,
                    'start': holiday.date_from,
                    'stop': holiday.date_to,
                    'allday': False,
                    'state': 'open',            # to block that meeting date in the calendar
                    'privacy': 'confidential'
                }
                #Add the partner_id (if exist) as an attendee
                if holiday.user_id and holiday.user_id.partner_id:
                    meeting_values['partner_ids'] = [(4, holiday.user_id.partner_id.id)]

                meeting = self.env['calendar.event'].with_context(no_mail_to_attendees=True).create(meeting_values)
                holiday._create_resource_leave()
                holiday.write({'meeting_id': meeting.id})
            elif holiday.holiday_type == 'category':
                leaves = self.env['hr.holidays']
                for employee in holiday.category_id.employee_ids:
                    values = holiday._prepare_create_by_category(employee)
                    leaves += self.with_context(mail_notify_force_send=False).create(values)
                # TODO is it necessary to interleave the calls?
                leaves.action_approve()
                if leaves and leaves[0].double_validation:
                    leaves.action_validate()
        return True

    @api.multi
    def action_refuse(self):
        if not self.env.user.has_group('hr_holidays.group_hr_holidays_user'):
            raise UserError(_('Only an HR Officer or Manager can refuse leave requests.'))

        manager = self.env['hr.employee'].search([('user_id', '=', self.env.uid)], limit=1)
        for holiday in self:
            if holiday.state not in ['confirm', 'validate', 'validate1']:
                raise UserError(_('Leave request must be confirmed or validated in order to refuse it.'))

            if holiday.state == 'validate1':
                holiday.write({'state': 'refuse', 'manager_id': manager.id})
            else:
                holiday.write({'state': 'refuse', 'manager_id2': manager.id})
            # Delete the meeting
            if holiday.meeting_id:
                holiday.meeting_id.unlink()
            # If a category that created several holidays, cancel all related
            holiday.linked_request_ids.action_refuse()
        self._remove_resource_leave()
        return True

    @api.multi
    def toggle_payslip_status(self):
        record_to_set_true = self.search([('id', 'in', self.ids), ('payslip_status', '=', False)])
        record_to_set_false = self - record_to_set_true
        return record_to_set_true.write({'payslip_status': True}) and record_to_set_false.write({'payslip_status': False})

    ####################################################
    # Messaging methods
    ####################################################

    @api.multi
    def _track_subtype(self, init_values):
        if 'state' in init_values and self.state == 'validate':
            return 'hr_holidays.mt_holidays_approved'
        elif 'state' in init_values and self.state == 'validate1':
            return 'hr_holidays.mt_holidays_first_validated'
        elif 'state' in init_values and self.state == 'confirm':
            return 'hr_holidays.mt_holidays_confirmed'
        elif 'state' in init_values and self.state == 'refuse':
            return 'hr_holidays.mt_holidays_refused'
        return super(Holidays, self)._track_subtype(init_values)

    @api.multi
    def _notification_recipients(self, message, groups):
        """ Handle HR users and officers recipients that can validate or refuse holidays
        directly from email. """
        groups = super(Holidays, self)._notification_recipients(message, groups)

        self.ensure_one()
        hr_actions = []
        if self.state == 'confirm':
            app_action = self._notification_link_helper('controller', controller='/hr_holidays/validate')
            hr_actions += [{'url': app_action, 'title': _('Approve')}]
        if self.state in ['confirm', 'validate', 'validate1']:
            ref_action = self._notification_link_helper('controller', controller='/hr_holidays/refuse')
            hr_actions += [{'url': ref_action, 'title': _('Refuse')}]

        new_group = (
            'group_hr_holidays_user', lambda partner: bool(partner.user_ids) and any(user.has_group('hr_holidays.group_hr_holidays_user') for user in partner.user_ids), {
                'actions': hr_actions,
            })

        return [new_group] + groups