create some helper functions for handling operation items in the database

app/src/main/kotlin/com/simplemobiletools/calendar/helpers/Constants.kt

@@ -124,3 +124,6 @@ val SOURCE_IMPORTED_ICS = 2
 // Google Sync
 val PRIMARY = "primary"
 val POPUP = "popup"
+val OPERATION_INSERT = 1
+val OPERATION_UPDATE = 2
+val OPERATION_DELETE = 3

app/src/main/kotlin/com/simplemobiletools/calendar/helpers/GoogleSyncQueueDB.kt

@@ -1,20 +1,20 @@
 package com.simplemobiletools.calendar.helpers
 
+import android.content.ContentValues
 import android.content.Context
+import android.database.Cursor
 import android.database.sqlite.SQLiteDatabase
 import android.database.sqlite.SQLiteOpenHelper
+import com.simplemobiletools.calendar.models.GoogleOperation
+import com.simplemobiletools.commons.extensions.getIntValue
 
 // database for storing operations performed on google events locally, while the user was offline
 class GoogleSyncQueueDB private constructor(val context: Context) : SQLiteOpenHelper(context, DB_NAME, null, DB_VERSION) {
-    private val MAIN_TABLE_NAME = "operations"
+    private val OPERATIONS_TABLE_NAME = "operations"
     private val COL_ID = "id"
     private val COL_EVENT_ID = "event_id"
     private val COL_OPERATION = "operation"
 
-    private val OPERATION_INSERT = 1
-    private val OPERATION_UPDATE = 2
-    private val OPERATION_DELETE = 3
-
     private val mDb: SQLiteDatabase = writableDatabase
 
     companion object {
@@ -31,10 +31,42 @@ class GoogleSyncQueueDB private constructor(val context: Context) : SQLiteOpenHe
     }
 
     override fun onCreate(db: SQLiteDatabase) {
-        db.execSQL("CREATE TABLE $MAIN_TABLE_NAME ($COL_ID INTEGER PRIMARY KEY, $COL_EVENT_ID INTEGER, $COL_OPERATION INTEGER)")
+        db.execSQL("CREATE TABLE $OPERATIONS_TABLE_NAME ($COL_ID INTEGER PRIMARY KEY, $COL_EVENT_ID INTEGER, $COL_OPERATION INTEGER)")
     }
 
     override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
 
     }
+
+    fun insert(operation: Int, eventId: Int) {
+        val contentValues = ContentValues().apply {
+            put(COL_OPERATION, operation)
+            put(COL_EVENT_ID, eventId)
+        }
+        mDb.insert(OPERATIONS_TABLE_NAME, null, contentValues)
+    }
+
+    fun getOperations(): ArrayList<GoogleOperation> {
+        val operations = ArrayList<GoogleOperation>()
+        val projection = arrayOf(COL_EVENT_ID, COL_OPERATION)
+        var cursor: Cursor? = null
+        try {
+            cursor = mDb.query(OPERATIONS_TABLE_NAME, projection, null, null, null, null, null)
+            if (cursor?.moveToFirst() == true) {
+                do {
+                    val eventId = cursor.getIntValue(COL_EVENT_ID)
+                    val operation = cursor.getIntValue(COL_OPERATION)
+                    operations.add(GoogleOperation(eventId, operation))
+                } while (cursor.moveToNext())
+            }
+        } finally {
+            cursor?.close()
+        }
+        return operations
+    }
+
+    fun delete(eventId: Int) {
+        val selection = "$COL_EVENT_ID = $eventId"
+        mDb.delete(OPERATIONS_TABLE_NAME, selection, null)
+    }
 }

app/src/main/kotlin/com/simplemobiletools/calendar/models/GoogleOperation.kt

@@ -0,0 +1,3 @@
+package com.simplemobiletools.calendar.models
+
+data class GoogleOperation(val eventId: Int, val operation: Int)