WIP [VOL-2811] - Incorporate preliminary onu-adapter-go code into opencord repo

- functionality: reason "initial-mib-downloaded" reached
- omciAgent removed, object relation restructured
- adapter code restructuring + internal lib interface update

Change-Id: Ie53450a5e2c093aaaf68fe652f95e7b4c4a014c7
Signed-off-by: Holger Hildebrandt <holger.hildebrandt@adtran.com>
diff --git a/internal/pkg/onuadaptercore/mib_sync.go b/internal/pkg/onuadaptercore/mib_sync.go
new file mode 100644
index 0000000..45c771b
--- /dev/null
+++ b/internal/pkg/onuadaptercore/mib_sync.go
@@ -0,0 +1,216 @@
+/*
+ * Copyright 2020-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//Package adaptercoreonu provides the utility for onu devices, flows and statistics
+package adaptercoreonu
+
+import (
+	"context"
+	"errors"
+
+	"github.com/looplab/fsm"
+
+	//"sync"
+	//"time"
+
+	//"github.com/opencord/voltha-lib-go/v3/pkg/kafka"
+	"github.com/opencord/omci-lib-go"
+	me "github.com/opencord/omci-lib-go/generated"
+	"github.com/opencord/voltha-lib-go/v3/pkg/log"
+	//ic "github.com/opencord/voltha-protos/v3/go/inter_container"
+	//"github.com/opencord/voltha-protos/v3/go/openflow_13"
+	//"github.com/opencord/voltha-protos/v3/go/voltha"
+)
+
+func (onuDeviceEntry *OnuDeviceEntry) logStateChange(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"event name": string(e.Event), "src state": string(e.Src), "dst state": string(e.Dst), "device-id": onuDeviceEntry.deviceID})
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterStartingState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"Start processing MibSync-msgs in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+
+	// create channel and start go routine for processing of MibSync messages
+	onuDeviceEntry.MibSyncChan = make(chan Message, 2048)
+	go onuDeviceEntry.ProcessMibSyncMessages()
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterLoadingMibTemplateState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"Start MibTemplate processing in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+	logger.Debug("function not implemented yet")
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterUploadingState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"send mibReset in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+	onuDeviceEntry.PDevOmciCC.sendMibReset(context.TODO(), ConstDefaultOmciTimeout, true)
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterInSyncState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"send notification to core in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+	onuDeviceEntry.transferSystemEvent(MibDatabaseSync)
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterExaminingMdsState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"Start GetMds processing in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+	logger.Debug("function not implemented yet")
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterResynchronizingState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"Start MibResync processing in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+	logger.Debug("function not implemented yet")
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterAuditingState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"Start MibResync processing in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+	logger.Debug("function not implemented yet")
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) enterOutOfSyncState(e *fsm.Event) {
+	logger.Debugw("MibSync FSM", log.Fields{"Start  MibReconcile processing in State": e.FSM.Current(), "device-id": onuDeviceEntry.deviceID})
+	logger.Debug("function not implemented yet")
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) ProcessMibSyncMessages( /*ctx context.Context*/ ) {
+	logger.Debugw("MibSync Msg", log.Fields{"Start routine to process OMCI-messages for device-id": onuDeviceEntry.deviceID})
+loop:
+	for {
+		select {
+		// case <-ctx.Done():
+		// 	logger.Info("MibSync Msg", log.Fields{"Message handling canceled via context for device-id": onuDeviceEntry.deviceID})
+		// 	break loop
+		case message, ok := <-onuDeviceEntry.MibSyncChan:
+			if !ok {
+				logger.Info("MibSync Msg", log.Fields{"Message couldn't be read from channel for device-id": onuDeviceEntry.deviceID})
+				break loop
+			}
+			logger.Debugw("MibSync Msg", log.Fields{"Received message on ONU MibSyncChan for device-id": onuDeviceEntry.deviceID})
+
+			switch message.Type {
+			case TestMsg:
+				msg, _ := message.Data.(TestMessage)
+				onuDeviceEntry.handleTestMsg(msg)
+			case OMCI:
+				msg, _ := message.Data.(OmciMessage)
+				onuDeviceEntry.handleOmciMessage(msg)
+			default:
+				logger.Warn("MibSync Msg", log.Fields{"Unknown message type received for device-id": onuDeviceEntry.deviceID, "message.Type": message.Type})
+			}
+		}
+	}
+	logger.Info("MibSync Msg", log.Fields{"Stopped handling of MibSyncChan for device-id": onuDeviceEntry.deviceID})
+	// TODO: only this action?
+	onuDeviceEntry.MibSyncFsm.Event("stop")
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) handleTestMsg(msg TestMessage) {
+
+	logger.Debugw("MibSync Msg", log.Fields{"TestMessage received for device-id": onuDeviceEntry.deviceID, "msg.TestMessageVal": msg.TestMessageVal})
+
+	switch msg.TestMessageVal {
+	case AnyTriggerForMibSyncUploadMib:
+		onuDeviceEntry.MibSyncFsm.Event("upload_mib")
+		logger.Debugw("MibSync Msg", log.Fields{"state": string(onuDeviceEntry.MibSyncFsm.Current())})
+	default:
+		logger.Warn("MibSync Msg", log.Fields{"Unknown message type received for device-id": onuDeviceEntry.deviceID, "msg.TestMessageVal": msg.TestMessageVal})
+	}
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) handleOmciMessage(msg OmciMessage) {
+
+	logger.Debugw("MibSync Msg", log.Fields{"OmciMessage received for device-id": onuDeviceEntry.deviceID,
+		"msgType": msg.OmciMsg.MessageType})
+
+	//further analysis could be done here based on msg.OmciMsg.Payload, e.g. verification of error code ...
+	switch msg.OmciMsg.MessageType {
+	case omci.MibResetResponseType:
+		msgLayer := (*msg.OmciPacket).Layer(omci.LayerTypeMibResetResponse)
+		if msgLayer == nil {
+			logger.Error("Omci Msg layer could not be detected")
+			return
+		}
+		msgObj, msgOk := msgLayer.(*omci.MibResetResponse)
+		if !msgOk {
+			logger.Error("Omci Msg layer could not be assigned")
+			return
+		}
+		logger.Debugw("MibResetResponse Data", log.Fields{"data-fields": msgObj})
+		if msgObj.Result != me.Success {
+			logger.Errorw("Omci MibResetResponse Error - strange - what to do?", log.Fields{"Error": msgObj.Result})
+			return
+		}
+		onuDeviceEntry.PDevOmciCC.sendMibUpload(context.TODO(), ConstDefaultOmciTimeout, true)
+	case omci.MibUploadResponseType:
+		msgLayer := (*msg.OmciPacket).Layer(omci.LayerTypeMibUploadResponse)
+		if msgLayer == nil {
+			logger.Error("Omci Msg layer could not be detected")
+			return
+		}
+		msgObj, msgOk := msgLayer.(*omci.MibUploadResponse)
+		if !msgOk {
+			logger.Error("Omci Msg layer could not be assigned")
+			return
+		}
+		logger.Debugw("MibUploadResponse Data for:", log.Fields{"deviceId": onuDeviceEntry.PDevOmciCC.deviceID, "data-fields": msgObj})
+		/* to be verified / reworked !!! */
+		onuDeviceEntry.PDevOmciCC.uploadNoOfCmds = msgObj.NumberOfCommands
+		if onuDeviceEntry.PDevOmciCC.uploadSequNo < onuDeviceEntry.PDevOmciCC.uploadNoOfCmds {
+			onuDeviceEntry.PDevOmciCC.sendMibUploadNext(context.TODO(), ConstDefaultOmciTimeout, true)
+		} else {
+			logger.Error("Invalid number of commands received for:", log.Fields{"deviceId": onuDeviceEntry.PDevOmciCC.deviceID, "uploadNoOfCmds": onuDeviceEntry.PDevOmciCC.uploadNoOfCmds})
+			//TODO right action?
+			onuDeviceEntry.MibSyncFsm.Event("timeout")
+		}
+	case omci.MibUploadNextResponseType:
+		msgLayer := (*msg.OmciPacket).Layer(omci.LayerTypeMibUploadNextResponse)
+		if msgLayer == nil {
+			logger.Error("Omci Msg layer could not be detected")
+			return
+		}
+		msgObj, msgOk := msgLayer.(*omci.MibUploadNextResponse)
+		if !msgOk {
+			logger.Error("Omci Msg layer could not be assigned")
+			return
+		}
+		logger.Debugw("MibUploadNextResponse Data for:", log.Fields{"deviceId": onuDeviceEntry.PDevOmciCC.deviceID, "data-fields": msgObj})
+		// TODO !!! content evaluation ?????
+		if onuDeviceEntry.PDevOmciCC.uploadSequNo < onuDeviceEntry.PDevOmciCC.uploadNoOfCmds {
+			onuDeviceEntry.PDevOmciCC.sendMibUploadNext(context.TODO(), ConstDefaultOmciTimeout, true)
+		} else {
+			//TODO
+			onuDeviceEntry.MibSyncFsm.Event("success")
+		}
+	}
+}
+
+func (onuDeviceEntry *OnuDeviceEntry) MibDbVolatileDict() error {
+	logger.Debug("MibVolatileDict- running from default Entry code")
+	return errors.New("not_implemented")
+}
+
+// func (onuDeviceEntry *OnuDeviceEntry) MibTemplateTask() error {
+// 	return errors.New("not_implemented")
+// }
+// func (onuDeviceEntry *OnuDeviceEntry) MibUploadTask() error {
+// 	return errors.New("not_implemented")
+// }
+// func (onuDeviceEntry *OnuDeviceEntry) GetMdsTask() error {
+// 	return errors.New("not_implemented")
+// }
+// func (onuDeviceEntry *OnuDeviceEntry) MibResyncTask() error {
+// 	return errors.New("not_implemented")
+// }
+// func (onuDeviceEntry *OnuDeviceEntry) MibReconcileTask() error {
+// 	return errors.New("not_implemented")
+// }