Refactor DmfsTask to use Entity for task data

Author: sunkup

lib/src/main/kotlin/at/bitfire/ical4android/DmfsTask.kt

@@ -8,6 +8,7 @@ package at.bitfire.ical4android
 
 import android.content.ContentUris
 import android.content.ContentValues
+import android.content.Entity
 import android.net.Uri
 import android.os.RemoteException
 import at.bitfire.synctools.mapping.tasks.DmfsTaskBuilder
@@ -20,47 +21,44 @@ import at.bitfire.synctools.storage.toContentValues
 import net.fortuna.ical4j.model.Parameter
 import net.fortuna.ical4j.model.parameter.RelType
 import net.fortuna.ical4j.model.property.RelatedTo
+import org.dmfs.tasks.contract.TaskContract
 import org.dmfs.tasks.contract.TaskContract.Properties
 import org.dmfs.tasks.contract.TaskContract.Tasks
 import java.io.FileNotFoundException
 import java.util.logging.Level
 import java.util.logging.Logger
 
 /**
- * Stores and retrieves VTODO iCalendar objects (represented as [Task]s) to/from the
- * tasks.org-content provider (currently tasks.org and OpenTasks).
+ * Stores and retrieves tasks to/from the tasks.org-content provider (currently tasks.org and
+ * OpenTasks).
  *
- * Extend this class to process specific fields of the task.
+ * A task in the context of this class is one row in the [TaskContract.Tasks] table,
+ * plus associated data rows (like alarms and reminders).
+ *
+ * Exceptions (of recurring tasks) have their own entries in the [TaskContract.Tasks] table and thus
+ * are separate.
  *
  * The SEQUENCE field is stored in [Tasks.SYNC_VERSION], so don't use [Tasks.SYNC_VERSION]
  * for anything else.
+ *
+ * @param taskList  task list where the task is stored
+ * @param values    entity with all columns, as returned by the calendar provider; [TaskContract.Tasks._ID] must be set to a non-null value
  */
+
 class DmfsTask(
-    val taskList: DmfsTaskList
+    val taskList: DmfsTaskList,
+    val values: Entity
 ) {
 
     private val logger = Logger.getLogger(javaClass.name)
 
-    var id: Long? = null
-    var syncId: String? = null
-    var eTag: String? = null
-    var flags: Int = 0
-
-
-    constructor(taskList: DmfsTaskList, values: ContentValues): this(taskList) {
-        id = values.getAsLong(Tasks._ID)
-        syncId = values.getAsString(Tasks._SYNC_ID)
-        eTag = values.getAsString(COLUMN_ETAG)
-        flags = values.getAsInteger(COLUMN_FLAGS) ?: 0
-    }
-
-    constructor(taskList: DmfsTaskList, task: Task, syncId: String?, eTag: String?, flags: Int): this(taskList) {
-        this.task = task
-        this.syncId = syncId
-        this.eTag = eTag
-        this.flags = flags
-    }
+    private val mainValues
+        get() = values.entityValues
 
+    var id: Long = mainValues.getAsLong(Tasks._ID)
+    var syncId: String? = mainValues.getAsString(Tasks._SYNC_ID)
+    var eTag: String? = mainValues.getAsString(COLUMN_ETAG)
+    var flags: Int = mainValues.getAsInteger(COLUMN_FLAGS) ?: 0
 
     var task: Task? = null
         /**

lib/src/main/kotlin/at/bitfire/synctools/storage/tasks/DmfsTaskList.kt

@@ -8,6 +8,7 @@ package at.bitfire.synctools.storage.tasks
 
 import android.content.ContentUris
 import android.content.ContentValues
+import android.content.Entity
 import android.net.Uri
 import android.os.RemoteException
 import at.bitfire.ical4android.DmfsTask
@@ -21,7 +22,7 @@ import java.util.LinkedList
 import java.util.logging.Logger
 
 /**
- * Represents a locally stored task list, containing [at.bitfire.ical4android.DmfsTask]s (tasks).
+ * Represents a locally stored task list, containing [DmfsTask]s (tasks).
  * Communicates with tasks.org-compatible content providers (currently tasks.org and OpenTasks) to store the tasks.
  */
 class DmfsTaskList(
@@ -59,25 +60,65 @@ class DmfsTaskList(
      * @param where selection
      * @param whereArgs arguments for selection
      *
-     * @return events from this task list which match the selection
+     * @return tasks from this task list which match the selection
      */
     fun findTasks(where: String? = null, whereArgs: Array<String>? = null): List<DmfsTask> {
         val tasks = LinkedList<DmfsTask>()
         try {
             val (protectedWhere, protectedWhereArgs) = whereWithTaskListId(where, whereArgs)
-            client.query(tasksUri(), null, protectedWhere, protectedWhereArgs, null)?.use { cursor ->
-                while (cursor.moveToNext())
-                    tasks += DmfsTask(this, cursor.toContentValues())
+            client.query(tasksUri(), arrayOf(TaskContract.Tasks._ID), protectedWhere, protectedWhereArgs, null)?.use { cursor ->
+                while (cursor.moveToNext()) {
+                    val taskId = cursor.getLong(0)
+                    val entity = getTaskEntity(taskId)
+                    if (entity != null)
+                        tasks += DmfsTask(this, entity)
+                }
             }
         } catch (e: RemoteException) {
             throw LocalStorageException("Couldn't query ${providerName.authority} tasks", e)
         }
         return tasks
     }
 
-    fun getTask(id: Long) = findTasks("${TaskContract.Tasks._ID}=?", arrayOf(id.toString())).firstOrNull()
-        ?: throw LocalStorageException("Couldn't query ${providerName.authority} tasks")
-    
+    /**
+     * Gets a task from this task list by given id.
+     *
+     * @return task from this task list which matches the selection
+     */
+    fun getTask(id: Long): DmfsTask? {
+        val values = getTaskEntity(id) ?: return null
+        return DmfsTask(this, values)
+    }
+
+    /**
+     * Retrieves a task as entity from this task list by given id and selection.
+     *
+     * @param where selection
+     * @param whereArgs arguments for selection
+     *
+     * @return task from this task list which matches the selection
+     */
+    fun getTaskEntity(id: Long, where: String? = null, whereArgs: Array<String>? = null): Entity? {
+        try {
+            client.query(taskUri(id, true), null, where, whereArgs, null)?.use { cursor ->
+                if (cursor.moveToFirst()) {
+                    // first row holds entity main values
+                    val entity = Entity(cursor.toContentValues())
+                    // remaining rows hold entity subvalues (extended properties)
+                    while (cursor.moveToNext()) {
+                        val cv = cursor.toContentValues()
+                        val mimetype = cv.getAsString(TaskContract.PropertyColumns.MIMETYPE) // CONTENT_ITEM_TYPE of extended property
+                        entity.addSubValue(tasksPropertyUri(mimetype), cv)
+                    }
+                    return entity
+                }
+            }
+        } catch (e: RemoteException) {
+            throw LocalStorageException("Couldn't query task entity", e)
+        }
+        return null
+    }
+
     /**
      * Updates tasks in this task list.
      *
@@ -155,6 +196,9 @@ class DmfsTaskList(
     fun tasksPropertiesUri() =
         TaskContract.Properties.getContentUri(providerName.authority).asSyncAdapter(account)
 
+    fun tasksPropertyUri(mimetype: String): Uri =
+        tasksPropertiesUri().buildUpon().appendPath(mimetype).build()!!
+
     /**
      * Restricts a given selection/where clause to this task list ID.
      *