Implements new way of sending shift reminder

lacagette_addons/lacagette_shifts/NEW_SHIFT_REMINDER.md

+After module updates, before activated new cron
+===============================================
+
+Run the following SQL command :
+
+UPDATE shift_registration 
+SET reminder_mail_sent = true
+WHERE id IN 
+(SELECT registration_id FROM  shift_mail_registration WHERE mail_sent = true AND write_date <= now() AND write_date > now() - '14 days'::interval);
+
+* then Unactivate previous cron
+
+activate new cron task
+ 
+

lacagette_addons/lacagette_shifts/data/email_template_data.xml

@@ -28,4 +28,21 @@
             </p>
             ]]></field>
     </record>
+
+    <record id="custom_shift_email_reminder" model="mail.template">
+        <field name="name">Mail rappel service</field>
+        <field name="model_id" ref="lacagette_shifts.model_shift_registration"/>
+        <field name="email_from">${(object.partner_id.company_id.email or '')|safe}</field>
+        <field name="email_to" >${object.partner_id.email|safe}</field>
+        <field name="lang">${object.partner_id.lang}</field>
+        <field name="reply_to">${object.company_id.email|safe}</field>
+        <field name="subject">Rappel du service ${object.shift_id.name}</field>
+        <field name="body_html"><![CDATA[
+            Bonjour ${object.name},
+            Texte en rapport avec le magasin.
+            ]]></field>
+    </record>
+
+
+
 </odoo>

lacagette_addons/lacagette_shifts/data/ir_cron.xml

@@ -19,4 +19,20 @@
         <field name="active" eval="False"/>
         <field name="priority">2</field>
     </record>
-</odoo>
+
\ No newline at end of file
+    <record forcecreate="True" id="cron_shift_reminder_email" model="ir.cron">
+        <field name="name">LaCagette Shift Email Reminder</field>
+        <field name="user_id" ref="base.user_root" />
+        <field name="interval_number">1</field>
+        <field name="interval_type">days</field>
+        <field name="numbercall">-1</field>
+        <field name="nextcall" eval="(DateTime.now() + timedelta(days=1)).strftime('%Y-%m-%d 20:00:00')"/>
+        <field name="doall" eval="False"/>
+        <field name="model" eval="'shift.registration'"/>
+        <field name="function" eval="'send_shift_reminder_emails'"/>
+        <field name="args" eval="'()'"/>
+        <field name="active" eval="False"/>
+        <field name="priority">2</field>
+    </record>
+
+</odoo>

lacagette_addons/lacagette_shifts/models/lacagette_shift_registrations.py

@@ -6,17 +6,28 @@ import datetime
 class ShiftRegistration(models.Model):
     _inherit = 'shift.registration'
 
+    reminder_mail_sent = fields.Boolean("Reminder mail has been sent", default= False)
+
     @api.multi
     def send_shift_missing_email(self):
         mail_template = self.env.ref('lacagette_shifts.missing_shift_email')
         if not mail_template:
             return False
-        
+
         for reg_target in self:
             mail_template.send_mail(reg_target.id)
-        
+
         return True
 
+    @api.multi
+    def send_shift_reminder_email(self):
+        mail_template =  self.env.ref('lacagette_shifts.custom_shift_email_reminder')
+        if not mail_template:
+            return False
+        for reg_target in self:
+            mail_template.send_mail(reg_target.id)
+            self.write({'reminder_mail_sent': True})
+        return True
 
     @api.model
     def send_shift_missing_emails(self):
@@ -30,3 +41,18 @@ class ShiftRegistration(models.Model):
             ('date_begin', '<', now.strftime("%Y-%m-%d %H:%M:%S"))
         ])
         reg_targets.send_shift_missing_email()
+
+    @api.model
+    def send_shift_reminder_emails(self):
+        shift_env = self.env['shift.registration']
+        # Find out the candidate shifts (between tomorrow and after tomorrow
+        # TODO : The time window could be changed, using odoo parameters 
+        now = datetime.datetime.now()
+        tomorrow = now + datetime.timedelta(hours=24)
+        after_tomorrow = tomorrow + datetime.timedelta(hours=24)
+        reg_targets = shift_env.search([
+            ('state', '=', 'open'),
+            ('reminder_mail_sent', '=', False),
+            ('date_begin', '>=', tomorrow.strftime("%Y-%m-%d %H:%M:%S")),
+            ('date_begin', '<', after_tomorrow.strftime("%Y-%m-%d %H:%M:%S"))])
+        reg_targets.send_shift_reminder_email()