/*
 * Copyright (C) 2017-2018 "IoT.bzh"
 * Author Sebastien Douheret <sebastien@iot.bzh>
 *
 * 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 xsapiv1

import (
	"encoding/json"
	"fmt"
)

// EventRegisterArgs Parameters (json format) of /events/register command
type EventRegisterArgs struct {
	Name   string `json:"name"`
	Filter string `json:"filter"`
}

// EventUnRegisterArgs Parameters of /events/unregister command
type EventUnRegisterArgs struct {
	Name string `json:"name"`
	ID   int    `json:"id"`
}

// EventMsg Message send
type EventMsg struct {
	Time          string      `json:"time"`
	FromSessionID string      `json:"sessionID"` // Session ID of client who produce this event
	Type          string      `json:"type"`
	Data          interface{} `json:"data"` // Data
}

// EventEvent Event send in WS when an internal event (eg. Syncthing event is received)
const (
	// EventTypePrefix Used as event prefix
	EventTypePrefix = "event:" // following by event type

	// Supported Events type
	EVTAll = EventTypePrefix + "all"

	EVTFolderChange      = EventTypePrefix + "folder-change"       // type EventMsg with Data type xsapiv1.FolderConfig
	EVTFolderStateChange = EventTypePrefix + "folder-state-change" // type EventMsg with Data type xsapiv1.FolderConfig

	EVTSDKAdd         = EventTypePrefix + "sdk-add"          // type EventMsg with Data type xsapiv1.SDK
	EVTSDKRemove      = EventTypePrefix + "sdk-remove"       // type EventMsg with Data type xsapiv1.SDK
	EVTSDKManagement  = EventTypePrefix + "sdk-management"   // type EventMsg with Data type xsapiv1.SDKManagementMsg
	EVTSDKStateChange = EventTypePrefix + "sdk-state-change" // type EventMsg with Data type xsapiv1.SDK

	EVTTargetAdd         = EventTypePrefix + "target-add"          // type EventMsg with Data type xsapiv1.TargetConfig
	EVTTargetRemove      = EventTypePrefix + "target-remove"       // type EventMsg with Data type xsapiv1.TargetConfig
	EVTTargetStateChange = EventTypePrefix + "target-state-change" // type EventMsg with Data type xsapiv1.TargetConfig

	EVTTargetTerminalAdd         = EventTypePrefix + "target-terminal-add"          // type EventMsg with Data type xsapiv1.TerminalConfig
	EVTTargetTerminalRemove      = EventTypePrefix + "target-terminal-remove"       // type EventMsg with Data type xsapiv1.TerminalConfig
	EVTTargetTerminalStateChange = EventTypePrefix + "target-terminal-state-change" // type EventMsg with Data type xsapiv1.TerminalConfig
)

// EVTAllList List of all supported events
var EVTAllList = []string{
	EVTFolderChange,
	EVTFolderStateChange,
	EVTSDKAdd,
	EVTSDKRemove,
	EVTSDKManagement,
	EVTSDKStateChange,
	EVTTargetAdd,
	EVTTargetRemove,
	EVTTargetStateChange,
	EVTTargetTerminalAdd,
	EVTTargetTerminalRemove,
	EVTTargetTerminalStateChange,
}

// DecodeFolderConfig Helper to decode Data field type FolderConfig
func (e *EventMsg) DecodeFolderConfig() (FolderConfig, error) {
	var err error
	f := FolderConfig{}
	switch e.Type {
	case EVTFolderChange, EVTFolderStateChange:
		d := []byte{}
		d, err = json.Marshal(e.Data)
		if err == nil {
			err = json.Unmarshal(d, &f)
		}
	default:
		err = fmt.Errorf("Invalid type")
	}
	return f, err
}

// DecodeSDKEvent Helper to decode Data field type SDK
func (e *EventMsg) DecodeSDKEvent() (SDK, error) {
	var err error
	s := SDK{}
	switch e.Type {
	case EVTSDKAdd, EVTSDKRemove, EVTSDKStateChange:
		d := []byte{}
		d, err = json.Marshal(e.Data)
		if err == nil {
			err = json.Unmarshal(d, &s)
		}
	default:
		err = fmt.Errorf("Invalid type")
	}
	return s, err
}

// DecodeTargetEvent Helper to decode Data field type TargetConfig
func (e *EventMsg) DecodeTargetEvent() (TargetConfig, error) {
	var err error
	p := TargetConfig{}
	switch e.Type {
	case EVTTargetAdd, EVTTargetRemove, EVTTargetStateChange:
		d := []byte{}
		d, err = json.Marshal(e.Data)
		if err == nil {
			err = json.Unmarshal(d, &p)
		}
	default:
		err = fmt.Errorf("Invalid type")
	}
	return p, err
}

// DecodeTerminalEvent Helper to decode Data field type TerminalConfig
func (e *EventMsg) DecodeTerminalEvent() (TerminalConfig, error) {
	var err error
	p := TerminalConfig{}
	switch e.Type {
	case EVTTargetTerminalAdd, EVTTargetTerminalRemove, EVTTargetTerminalStateChange:
		d := []byte{}
		d, err = json.Marshal(e.Data)
		if err == nil {
			err = json.Unmarshal(d, &p)
		}
	default:
		err = fmt.Errorf("Invalid type")
	}
	return p, err
}