feat(mail) Introduce option SOGoVacationAllowZeroDays to allow a sieve vacation days value of 0

Documentation/SOGoInstallationGuide.asciidoc

@@ -2443,6 +2443,16 @@ appended to the user's vacation message. For example:
 
 See `SOGoVacationHeaderTemplateFile` for available template variables.
 
+|D |SOGoVacationAllowZeroDays
+|Parameter used to enable an option of 0 for the vacation days setting.
+A value of 0 means that auto response mails are sent for every incoming mail.
+
+This option has to be supported by the IMAP host
+(see https://doc.dovecot.org/2.3/settings/pigeonhole-ext/vacation/#pigeonhole_setting-sieve_vacation_min_period
+for instructions regarding Dovecot/Pigeonhole).
+
+Defaults to `NO` when unset.
+
 |D |SOGoForwardEnabled
 |Parameter used to activate the edition from the preferences window of a
 forwarding email address. Requires Sieve script support on the IMAP

SoObjects/SOGo/SOGoDomainDefaults.h

@@ -60,6 +60,7 @@
 - (NSString *) vacationDefaultSubject;
 - (NSString *) vacationHeaderTemplateFile;
 - (NSString *) vacationFooterTemplateFile;
+- (BOOL) vacationAllowZeroDays;
 - (NSString *) mailingMechanism;
 - (NSString *) smtpServer;
 - (BOOL)smtpMasterUserEnabled;

SoObjects/SOGo/SOGoDomainDefaults.m

@@ -277,6 +277,18 @@
   return [self stringForKey: @"SOGoVacationFooterTemplateFile"];
 }
 
+- (BOOL) vacationAllowZeroDays
+{
+  id o;
+
+  o = [self stringForKey: @"SOGoVacationAllowZeroDays"];
+
+  if (o)
+    return [o boolValue];
+
+  return NO;
+}
+
 - (NSString *) mailingMechanism
 {
   NSString *mailingMechanism;

SoObjects/SOGo/SOGoSieveManager.m

@@ -1016,8 +1016,8 @@ static NSString *sieveScriptName = @"sogo";
             text = [NSString stringWithFormat: @"%@%@", text, [templateFile textForUser: user]];
         }
 
-      if (days == 0)
-        days = 7;
+      if (days <= 0)
+        days = [dd vacationAllowZeroDays] ? 0 : 7;
 
       vacation_script = [NSMutableString string];
 

UI/PreferencesUI/UIxPreferences.m

@@ -1000,12 +1000,16 @@ static NSArray *reminderValues = nil;
 //
 - (NSArray *) daysBetweenResponsesList
 {
-  static NSArray *daysBetweenResponses = nil;
+  static NSMutableArray *daysBetweenResponses = nil;
 
   if (!daysBetweenResponses)
     {
-      daysBetweenResponses = [NSArray arrayWithObjects: @"1", @"2", @"3",
+      daysBetweenResponses = [NSMutableArray arrayWithObjects: @"1", @"2", @"3",
                                       @"5", @"7", @"14", @"21", @"30", nil];
+      if ([[user domainDefaults] vacationAllowZeroDays])
+        {
+          [daysBetweenResponses insertObject:@"0" atIndex:0];
+        }
       [daysBetweenResponses retain];
     }
 

UI/Templates/PreferencesUI/UIxPreferences.wox

@@ -1175,7 +1175,12 @@
                                ng-model="app.preferences.defaults.Vacation.daysBetweenResponse">
                       <var:foreach list="daysBetweenResponsesList" item="item">
                         <md-option var:value="item">
-                          <var:string value="item"/>
+                          <var:if condition="item" const:value="0">
+                             <i><var:string label:value="Always send vacation message response"/></i>
+                          </var:if>
+                          <var:if condition="item" const:value="0" const:negate="YES">
+                             <var:string value="item"/>
+                          </var:if>
                         </md-option>
                       </var:foreach>
                     </md-select>
@@ -1499,4 +1504,4 @@
   </script>
 
 
-</var:component>
+</var:component>