creating the structure of contact exporting

app/src/main/kotlin/com/simplemobiletools/contacts/helpers/VcfExporter.kt

@@ -0,0 +1,37 @@
+package com.simplemobiletools.contacts.helpers
+
+import com.simplemobiletools.commons.activities.BaseSimpleActivity
+import com.simplemobiletools.commons.extensions.getFileOutputStream
+import com.simplemobiletools.contacts.helpers.VcfExporter.ExportResult.*
+import com.simplemobiletools.contacts.models.Contact
+import java.io.File
+
+class VcfExporter() {
+    enum class ExportResult {
+        EXPORT_FAIL, EXPORT_OK, EXPORT_PARTIAL
+    }
+
+    private var contactsExported = 0
+    private var contactsFailed = 0
+
+    fun exportContacts(activity: BaseSimpleActivity, file: File, contacts: ArrayList<Contact>, callback: (result: ExportResult) -> Unit) {
+        activity.getFileOutputStream(file) {
+            if (it == null) {
+                callback(EXPORT_FAIL)
+                return@getFileOutputStream
+            }
+
+            it.bufferedWriter().use { out ->
+                for (contact in contacts) {
+
+                }
+            }
+        }
+
+        callback(when {
+            contactsExported == 0 -> EXPORT_FAIL
+            contactsFailed > 0 -> EXPORT_PARTIAL
+            else -> EXPORT_OK
+        })
+    }
+}