Recurrent monthly event, add possibility to specify the week day #149 (#155)

* added a new event generator
* added support for dynamic monthly recurrence
* refactored JS
* added translations
* added comments
* added hint for frequency

Author: ChiuchiuSorin

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/AbstractRecurrentEventGenerator.java

@@ -61,7 +61,7 @@ public abstract class AbstractRecurrentEventGenerator implements RecurrentEventG
      * E.g. in case of weekly events increment it by one week.
      * @param cal the calendar to increment; should never be null
      */
-    protected abstract void incrementCalendarByOnePeriod(Calendar cal);
+    protected abstract void incrementCalendarByOnePeriod(Calendar cal, int... pos);
 
     /**
      * generate a list of event instances for the given date range
@@ -117,7 +117,7 @@ public List<EventInstance> generate(final XWikiDocument event, final Date dateFr
 
     // separate helper method to actually create the events
     // to keep checkstyle from complaining
-    private List<EventInstance> createEventInstances(final XWikiDocument event, final Date startDate,
+    protected List<EventInstance> createEventInstances(final XWikiDocument event, final Date startDate,
         final long duration, final Date dateFrom, final Date dateTo)
     {
         Calendar cal = Calendar.getInstance();

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/BiWeeklyEventGenerator.java

@@ -40,7 +40,7 @@ public class BiWeeklyEventGenerator extends AbstractRecurrentEventGenerator
     /**
      * increment the calendar by two weeks.
      */
-    protected void incrementCalendarByOnePeriod(Calendar cal)
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... pos)
     {
         cal.add(Calendar.WEEK_OF_YEAR, 2);
     }

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/DailyEventGenerator.java

@@ -40,7 +40,7 @@ public class DailyEventGenerator extends AbstractRecurrentEventGenerator
     /**
      * increment the calendar by one day.
      */
-    protected void incrementCalendarByOnePeriod(Calendar cal)
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... pos)
     {
         cal.add(Calendar.DAY_OF_YEAR, 1);
     }

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/MonthlyEventGenerator.java

@@ -41,7 +41,7 @@ public class MonthlyEventGenerator extends AbstractRecurrentEventGenerator
     /**
      * increment the calendar by one month.
      */
-    protected void incrementCalendarByOnePeriod(Calendar cal)
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... pos)
     {
         cal.add(Calendar.MONTH, 1);
     }

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/MonthlySpecificEventGenerator.java

@@ -0,0 +1,126 @@
+/*
+ * See the NOTICE file distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this software; if not, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
+ */
+package org.xwiki.contrib.moccacalendar.internal.generators;
+
+import java.util.ArrayList;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.List;
+
+import javax.inject.Named;
+import javax.inject.Singleton;
+
+import org.joda.time.DateTime;
+import org.xwiki.component.annotation.Component;
+import org.xwiki.contrib.moccacalendar.EventInstance;
+
+import com.xpn.xwiki.doc.XWikiDocument;
+
+/**
+ * A generator for monthly events that take place on a specific day.
+ *
+ * @version $Id: $
+ * @since 2.16
+ */
+@Component
+@Singleton
+@Named("monthlySpecific")
+public class MonthlySpecificEventGenerator extends AbstractRecurrentEventGenerator
+{
+    /**
+     * Increment the calendar by one month, to a specific day.
+     */
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... occurrence)
+    {
+        int originalDayOfWeek = cal.get(Calendar.DAY_OF_WEEK);
+
+        cal.set(Calendar.DAY_OF_MONTH, 1);
+        cal.add(Calendar.MONTH, 1);
+        int nextMonth = cal.get(Calendar.MONTH);
+
+        int weekdayCount = 0;
+        int lastOccurrenceDay = 1;
+        while (cal.get(Calendar.MONTH) == nextMonth) {
+            if (cal.get(Calendar.DAY_OF_WEEK) == originalDayOfWeek) {
+                lastOccurrenceDay = cal.get(Calendar.DAY_OF_MONTH);
+                weekdayCount++;
+                if (weekdayCount == occurrence[0]) {
+                    return;
+                }
+            }
+            cal.add(Calendar.DAY_OF_MONTH, 1);
+        }
+
+        cal.add(Calendar.DAY_OF_MONTH, -1);
+        cal.set(Calendar.DAY_OF_MONTH, lastOccurrenceDay);
+    }
+
+    @Override
+    protected List<EventInstance> createEventInstances(final XWikiDocument event, final Date startDate,
+        final long duration, final Date dateFrom, final Date dateTo)
+    {
+        Calendar cal = Calendar.getInstance();
+        cal.setTime(startDate);
+        int occurrence = getOccurrence(cal);
+        while (cal.getTimeInMillis() + duration < dateFrom.getTime()) {
+            incrementCalendarByOnePeriod(cal, occurrence);
+        }
+        List<EventInstance> eventInstances = new ArrayList<>();
+        while (cal.getTime().compareTo(dateTo) <= 0) {
+            EventInstance instance = new EventInstance();
+            instance.setStartDate(new DateTime(cal.getTimeInMillis()));
+            instance.setEndDate(new DateTime(cal.getTimeInMillis() + duration));
+
+            eventInstances.add(instance);
+
+            if (eventInstances.size() >= MAX_INSTANCES) {
+                break;
+            }
+
+            incrementCalendarByOnePeriod(cal, occurrence);
+        }
+
+        return eventInstances;
+    }
+
+    /**
+     * Calculates the occurrence index of the day of the week for the date set in calendar.
+     *
+     * @param cal the {@link Calendar} instance representing the target date
+     * @return the number of times the day of the week set in calendar occurred in the month
+     */
+    private int getOccurrence(Calendar cal)
+    {
+        int originalDayOfWeek = cal.get(Calendar.DAY_OF_WEEK);
+        int originalDay = cal.get(Calendar.DAY_OF_MONTH);
+        int originalMonth = cal.get(Calendar.MONTH);
+
+        Calendar temp = (Calendar) cal.clone();
+        temp.set(Calendar.DAY_OF_MONTH, 1);
+        int occurrence = 0;
+        while (temp.get(Calendar.MONTH) == originalMonth && temp.get(Calendar.DAY_OF_MONTH) <= originalDay) {
+            if (temp.get(Calendar.DAY_OF_WEEK) == originalDayOfWeek) {
+                occurrence++;
+            }
+            temp.add(Calendar.DAY_OF_MONTH, 1);
+        }
+        return occurrence;
+    }
+}

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/QuarterlyEventGenerator.java

@@ -40,7 +40,7 @@ public class QuarterlyEventGenerator extends AbstractRecurrentEventGenerator
     /**
      * increment the calendar by three months.
      */
-    protected void incrementCalendarByOnePeriod(Calendar cal)
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... pos)
     {
         cal.add(Calendar.MONTH, 3);
     }

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/WeeklyEventGenerator.java

@@ -40,7 +40,7 @@ public class WeeklyEventGenerator extends AbstractRecurrentEventGenerator
     /**
      * increment the calendar by one week.
      */
-    protected void incrementCalendarByOnePeriod(Calendar cal)
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... pos)
     {
         cal.add(Calendar.WEEK_OF_YEAR, 1);
     }

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/WorkDaysEventGenerator.java

@@ -41,7 +41,7 @@ public class WorkDaysEventGenerator extends AbstractRecurrentEventGenerator
      * increment the calendar by one day, skipping weekends.
      * TODO: configure which days are weekdays
      */
-    protected void incrementCalendarByOnePeriod(Calendar cal)
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... pos)
     {
         do {
             cal.add(Calendar.DAY_OF_YEAR, 1);

application-mocca-calendar-api/src/main/java/org/xwiki/contrib/moccacalendar/internal/generators/YearlyEventGenerator.java

@@ -40,7 +40,7 @@ public class YearlyEventGenerator extends AbstractRecurrentEventGenerator
     /**
      * increment the calendar by one year.
      */
-    protected void incrementCalendarByOnePeriod(Calendar cal)
+    protected void incrementCalendarByOnePeriod(Calendar cal, int... pos)
     {
         cal.add(Calendar.YEAR, 1);
     }

application-mocca-calendar-api/src/main/resources/META-INF/components.txt

@@ -8,6 +8,7 @@ org.xwiki.contrib.moccacalendar.internal.generators.WorkDaysEventGenerator
 org.xwiki.contrib.moccacalendar.internal.generators.WeeklyEventGenerator
 org.xwiki.contrib.moccacalendar.internal.generators.BiWeeklyEventGenerator
 org.xwiki.contrib.moccacalendar.internal.generators.MonthlyEventGenerator
+org.xwiki.contrib.moccacalendar.internal.generators.MonthlySpecificEventGenerator
 org.xwiki.contrib.moccacalendar.internal.generators.QuarterlyEventGenerator
 org.xwiki.contrib.moccacalendar.internal.generators.YearlyEventGenerator
 org.xwiki.contrib.moccacalendar.internal.meetings.MeetingEventSource