// Package realtimedata define real time data operation functions
package realtimedata

import (
	"context"
	"encoding/json"
	"fmt"
	"time"

	"modelRT/config"
	"modelRT/constants"
	"modelRT/diagram"
	"modelRT/logger"
	"modelRT/network"
	"modelRT/orm"
	"modelRT/pool"
	"modelRT/util"

	"github.com/confluentinc/confluent-kafka-go/kafka"
)

var (
	// RealTimeDataChan define channel of real time data receive
	RealTimeDataChan   chan network.RealTimeDataReceiveRequest
	globalComputeState *MeasComputeState
)

func init() {
	RealTimeDataChan = make(chan network.RealTimeDataReceiveRequest, 100)
	globalComputeState = NewMeasComputeState()
}

// StartRealTimeDataComputing define func to start real time data process goroutines by measurement info
func StartRealTimeDataComputing(ctx context.Context, measurements []orm.Measurement) {
	for _, measurement := range measurements {
		enableValue, exist := measurement.EventPlan["enable"]
		enable, ok := enableValue.(bool)
		if !exist || !enable {
			logger.Info(ctx, "measurement object do not need real time data computing", "measurement_uuid", measurement.ComponentUUID)
			continue
		}

		if !ok {
			logger.Error(ctx, "covert enable variable to boolean type failed", "measurement_uuid", measurement.ComponentUUID, "enable", enableValue)
			continue
		}

		// TODO 启动协程准备查询 redis 数据进行计算
	}
}

// ReceiveChan define func to real time data receive and process
func ReceiveChan(ctx context.Context, consumerConfig *kafka.ConfigMap, topics []string, duration float32) {
	consumer, err := kafka.NewConsumer(consumerConfig)
	if err != nil {
		logger.Error(ctx, "create kafka consumer failed", "error", err)
		return
	}
	defer consumer.Close()

	err = consumer.SubscribeTopics(topics, nil)
	if err != nil {
		logger.Error(ctx, "subscribe kafka topics failed", "topic", topics, "error", err)
		return
	}

	batchSize := 100
	batchTimeout := util.SecondsToDuration(duration)
	messages := make([]*kafka.Message, 0, batchSize)
	lastCommit := time.Now()
	logger.Info(ctx, "start consuming from kafka", "topic", topics)
	for {
		select {
		case <-ctx.Done():
			logger.Info(ctx, "stop real time data computing by context cancel")
			return
		case realTimeData := <-RealTimeDataChan:
			componentUUID := realTimeData.PayLoad.ComponentUUID
			component, err := diagram.GetComponentMap(componentUUID)
			if err != nil {
				logger.Error(ctx, "query component info from diagram map by componet id failed", "component_uuid", componentUUID, "error", err)
				continue
			}

			componentType := component.Type
			if componentType != constants.DemoType {
				logger.Error(ctx, "can not process real time data of component type not equal DemoType", "component_uuid", componentUUID)
				continue
			}

			var anchorName string
			var compareValUpperLimit, compareValLowerLimit float64
			var anchorRealTimeData []float64
			var calculateFunc func(archorValue float64, args ...float64) float64

			// calculateFunc, params := config.SelectAnchorCalculateFuncAndParams(componentType, anchorName, componentData)

			for _, param := range realTimeData.PayLoad.Values {
				anchorRealTimeData = append(anchorRealTimeData, param.Value)
			}

			anchorConfig := config.AnchorParamConfig{
				AnchorParamBaseConfig: config.AnchorParamBaseConfig{
					ComponentUUID:        componentUUID,
					AnchorName:           anchorName,
					CompareValUpperLimit: compareValUpperLimit,
					CompareValLowerLimit: compareValLowerLimit,
					AnchorRealTimeData:   anchorRealTimeData,
				},
				CalculateFunc:   calculateFunc,
				CalculateParams: []float64{},
			}
			anchorChan, err := pool.GetAnchorParamChan(ctx, componentUUID)
			if err != nil {
				logger.Error(ctx, "get anchor param chan failed", "component_uuid", componentUUID, "error", err)
				continue
			}
			anchorChan <- anchorConfig
		default:
			msg, err := consumer.ReadMessage(batchTimeout)
			if err != nil {
				if err.(kafka.Error).Code() == kafka.ErrTimedOut {
					// process accumulated messages when timeout
					if len(messages) > 0 {
						processMessageBatch(ctx, messages)
						consumer.Commit()
						messages = messages[:0]
					}
					continue
				}
				logger.Error(ctx, "read message from kafka failed", "error", err, "msg", msg)
				continue
			}

			messages = append(messages, msg)
			// process messages when batch size or timeout period is reached
			if len(messages) >= batchSize || time.Since(lastCommit) >= batchTimeout {
				processMessageBatch(ctx, messages)
				consumer.Commit()
				messages = messages[:0]
				lastCommit = time.Now()
			}
		}
	}
}

type RealTimeDataPayload struct {
	ComponentUUID string
	Values        []float64
}

type RealTimeData struct {
	Payload RealTimeDataPayload
}

func parseKafkaMessage(msgValue []byte) (*RealTimeData, error) {
	var realTimeData RealTimeData
	err := json.Unmarshal(msgValue, &realTimeData)
	if err != nil {
		return nil, fmt.Errorf("unmarshal real time data failed: %w", err)
	}
	return &realTimeData, nil
}

func processRealTimeData(ctx context.Context, realTimeData *RealTimeData) {
	componentUUID := realTimeData.Payload.ComponentUUID
	component, err := diagram.GetComponentMap(componentUUID)
	if err != nil {
		logger.Error(ctx, "query component info from diagram map by component id failed",
			"component_uuid", componentUUID, "error", err)
		return
	}

	componentType := component.Type
	if componentType != constants.DemoType {
		logger.Error(ctx, "can not process real time data of component type not equal DemoType",
			"component_uuid", componentUUID)
		return
	}

	var anchorName string
	var compareValUpperLimit, compareValLowerLimit float64
	var anchorRealTimeData []float64
	var calculateFunc func(archorValue float64, args ...float64) float64

	// 收集实时数据
	for _, param := range realTimeData.Payload.Values {
		anchorRealTimeData = append(anchorRealTimeData, param)
	}

	anchorConfig := config.AnchorParamConfig{
		AnchorParamBaseConfig: config.AnchorParamBaseConfig{
			ComponentUUID:        componentUUID,
			AnchorName:           anchorName,
			CompareValUpperLimit: compareValUpperLimit,
			CompareValLowerLimit: compareValLowerLimit,
			AnchorRealTimeData:   anchorRealTimeData,
		},
		CalculateFunc:   calculateFunc,
		CalculateParams: []float64{},
	}

	anchorChan, err := pool.GetAnchorParamChan(ctx, componentUUID)
	if err != nil {
		logger.Error(ctx, "get anchor param chan failed",
			"component_uuid", componentUUID, "error", err)
		return
	}

	// TODO 使用select避免channel阻塞
	select {
	case anchorChan <- anchorConfig:
		// 成功发送
	case <-ctx.Done():
		logger.Info(ctx, "context done while sending to anchor chan")
	case <-time.After(5 * time.Second):
		logger.Error(ctx, "timeout sending to anchor chan", "component_uuid", componentUUID)
	}
}

// processMessageBatch define func to bathc process kafka message
func processMessageBatch(ctx context.Context, messages []*kafka.Message) {
	for _, msg := range messages {
		realTimeData, err := parseKafkaMessage(msg.Value)
		if err != nil {
			logger.Error(ctx, "parse kafka message failed", "error", err, "msg", msg)
			continue
		}
		go processRealTimeData(ctx, realTimeData)
	}
}