Add new Android event builder logic (#65)

* Split legacy Android event builder logic into separate builders

- Introduce `AndroidEventFieldBuilder` interface
- Create `TitleBuilder` for handling event titles
- Refactor `LegacyAndroidEventBuilder2` to use both new and legacy builders

* KDoc

* KDoc: null

Author: rfc2822

lib/src/main/kotlin/at/bitfire/synctools/mapping/calendar/LegacyAndroidEventBuilder2.kt

@@ -28,6 +28,8 @@ import at.bitfire.ical4android.util.TimeApiExtensions.toLocalTime
 import at.bitfire.ical4android.util.TimeApiExtensions.toRfc5545Duration
 import at.bitfire.ical4android.util.TimeApiExtensions.toZonedDateTime
 import at.bitfire.synctools.exception.InvalidLocalResourceException
+import at.bitfire.synctools.mapping.calendar.builder.AndroidEventFieldBuilder
+import at.bitfire.synctools.mapping.calendar.builder.TitleBuilder
 import at.bitfire.synctools.storage.calendar.AndroidCalendar
 import at.bitfire.synctools.storage.calendar.AndroidEvent2
 import at.bitfire.synctools.storage.calendar.EventAndExceptions
@@ -59,6 +61,9 @@ import java.util.logging.Logger
  *
  * Important: To use recurrence exceptions, you MUST set _SYNC_ID and ORIGINAL_SYNC_ID
  * in populateEvent() / buildEvent. Setting _ID and ORIGINAL_ID is not sufficient.
+ *
+ * Note: "Legacy" will be removed from the class name as soon as the [Event] dependency is
+ * replaced by [at.bitfire.synctools.icalendar.AssociatedEvents].
  */
 class LegacyAndroidEventBuilder2(
     private val calendar: AndroidCalendar,
@@ -92,6 +97,13 @@ class LegacyAndroidEventBuilder2(
         val entity = Entity(row)
         val from = recurrence ?: event
 
+        // new builders
+
+        for (builder in fieldBuilders())
+            builder.build(from = from, main = event, to = entity)
+
+        // legacy fields
+
         for (reminder in from.alarms)
             entity.addSubValue(Reminders.CONTENT_URI, buildReminder(reminder))
 
@@ -328,7 +340,6 @@ class LegacyAndroidEventBuilder2(
         }
 
         // text fields
-        row.put(Events.TITLE, from.summary)
         row.put(Events.EVENT_LOCATION, from.location)
         row.put(Events.DESCRIPTION, from.description)
 
@@ -498,4 +509,9 @@ class LegacyAndroidEventBuilder2(
         ExtendedProperties.VALUE to url
     )
 
+
+    private fun fieldBuilders(): Array<AndroidEventFieldBuilder> = arrayOf(
+        TitleBuilder()
+    )
+
 }

lib/src/main/kotlin/at/bitfire/synctools/mapping/calendar/builder/AndroidEventFieldBuilder.kt

@@ -0,0 +1,36 @@
+/*
+ * This file is part of bitfireAT/synctools which is released under GPLv3.
+ * Copyright © All Contributors. See the LICENSE and AUTHOR files in the root directory for details.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package at.bitfire.synctools.mapping.calendar.builder
+
+import android.content.Entity
+import at.bitfire.ical4android.Event
+
+interface AndroidEventFieldBuilder {
+
+    /**
+     * Maps the given event into the provided [Entity].
+     *
+     * If [from] references the same object as [main], this method is called for a main event (not an exception).
+     * If [from] references another object as [main], this method is called for an exception (not a main event).
+     *
+     * So you can use (note the referential equality operator):
+     *
+     * ```
+     * val buildsMainEvent = from === main
+     * ```
+     *
+     * Note: The result of the mapping is used to either create or update the event row in the content provider.
+     * For updates, explicit `null` values are required for fields that should be `null` (otherwise the value
+     * wouldn't be updated to `null` in case of an event update).
+     *
+     * @param from  event to map
+     * @param main  main event
+     * @param to    destination object where built values are stored (set `null` values, see note)
+     */
+    fun build(from: Event, main: Event, to: Entity)
+
+}

lib/src/main/kotlin/at/bitfire/synctools/mapping/calendar/builder/TitleBuilder.kt

@@ -0,0 +1,20 @@
+/*
+ * This file is part of bitfireAT/synctools which is released under GPLv3.
+ * Copyright © All Contributors. See the LICENSE and AUTHOR files in the root directory for details.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package at.bitfire.synctools.mapping.calendar.builder
+
+import android.content.Entity
+import android.provider.CalendarContract.Events
+import at.bitfire.ical4android.Event
+import at.bitfire.vcard4android.Utils.trimToNull
+
+class TitleBuilder: AndroidEventFieldBuilder {
+
+    override fun build(from: Event, main: Event, to: Entity) {
+        to.entityValues.put(Events.TITLE, from.summary.trimToNull())
+    }
+
+}

lib/src/test/kotlin/at/bitfire/synctools/mapping/calendar/builder/TitleBuilderTest.kt

@@ -0,0 +1,60 @@
+/*
+ * This file is part of bitfireAT/synctools which is released under GPLv3.
+ * Copyright © All Contributors. See the LICENSE and AUTHOR files in the root directory for details.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package at.bitfire.synctools.mapping.calendar.builder
+
+import android.content.ContentValues
+import android.content.Entity
+import android.provider.CalendarContract.Events
+import at.bitfire.ical4android.Event
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+
+@RunWith(RobolectricTestRunner::class)
+class TitleBuilderTest {
+
+    private val builder = TitleBuilder()
+
+    @Test
+    fun `No SUMMARY`() {
+        val result = Entity(ContentValues())
+        builder.build(
+            from = Event(),
+            main = Event(),
+            to = result
+        )
+        assertTrue(result.entityValues.containsKey(Events.TITLE))
+        assertNull(result.entityValues.get(Events.TITLE))
+    }
+
+    @Test
+    fun `SUMMARY is blank`() {
+        val result = Entity(ContentValues())
+        builder.build(
+            from = Event(summary = ""),
+            main = Event(),
+            to = result
+        )
+        assertTrue(result.entityValues.containsKey(Events.TITLE))
+        assertNull(result.entityValues.get(Events.TITLE))
+    }
+
+    @Test
+    fun `SUMMARY is text`() {
+        val result = Entity(ContentValues())
+        builder.build(
+            from = Event(summary = "Event Summary"),
+            main = Event(),
+            to = result
+        )
+        assertEquals("Event Summary", result.entityValues.getAsString(Events.TITLE))
+    }
+
+}