// Copyright 2021-2023 EMQ Technologies Co., Ltd.
//
// 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.

// 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.

//go:build plugins
// +build plugins

package main

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

	_ "github.com/influxdata/influxdb1-client/v2"
	client "github.com/influxdata/influxdb1-client/v2"

	"github.com/lf-edge/ekuiper/internal/topo/transform"
	"github.com/lf-edge/ekuiper/pkg/api"
)

type influxSink struct {
	addr         string
	username     string
	password     string
	measurement  string
	databaseName string
	tagKey       string
	tagValue     string
	dataField    string
	fields       []string
	cli          client.Client
	fieldMap     map[string]interface{}
	hasTransform bool
}

func (m *influxSink) Configure(props map[string]interface{}) error {
	if i, ok := props["addr"]; ok {
		if i, ok := i.(string); ok {
			m.addr = i
		}
	}
	if i, ok := props["username"]; ok {
		if i, ok := i.(string); ok {
			m.username = i
		}
	}
	if i, ok := props["password"]; ok {
		if i, ok := i.(string); ok {
			m.password = i
		}
	}
	if i, ok := props["measurement"]; ok {
		if i, ok := i.(string); ok {
			m.measurement = i
		}
	}
	if i, ok := props["databasename"]; ok {
		if i, ok := i.(string); ok {
			m.databaseName = i
		}
	}
	if i, ok := props["tagkey"]; ok {
		if i, ok := i.(string); ok {
			m.tagKey = i
		}
	}
	if i, ok := props["tagvalue"]; ok {
		if i, ok := i.(string); ok {
			m.tagValue = i
		}
	}
	if i, ok := props["dataField"]; ok {
		if i, ok := i.(string); ok {
			m.dataField = i
		}
	}
	if i, ok := props["fields"]; ok {
		if i, ok := i.([]interface{}); ok {
			for _, v := range i {
				if v, ok := v.(string); ok {
					m.fields = append(m.fields, v)
				}
			}
		}
	}
	if i, ok := props["dataTemplate"]; ok {
		if i, ok := i.(string); ok && i != "" {
			m.hasTransform = true
		}
	}
	return nil
}

func (m *influxSink) Open(ctx api.StreamContext) (err error) {
	logger := ctx.GetLogger()
	logger.Debug("Opening influx sink")
	m.cli, err = client.NewHTTPClient(client.HTTPConfig{
		Addr:     m.addr,
		Username: m.username,
		Password: m.password,
	})
	if err != nil {
		logger.Debug(err)
		return err
	}
	return nil
}

func (m *influxSink) Collect(ctx api.StreamContext, data interface{}) error {
	logger := ctx.GetLogger()
	if m.hasTransform {
		jsonBytes, _, err := ctx.TransformOutput(data)
		if err != nil {
			return err
		}
		m := make(map[string]interface{})
		err = json.Unmarshal(jsonBytes, &m)
		if err != nil {
			return fmt.Errorf("fail to decode data %s after applying dataTemplate for error %v", string(jsonBytes), err)
		}
		data = m
	} else {
		d, _, err := transform.TransItem(data, m.dataField, m.fields)
		if err != nil {
			return fmt.Errorf("fail to select fields %v for data %v", m.fields, data)
		}
		data = d
	}
	var output map[string]interface{}
	switch v := data.(type) {
	case map[string]interface{}:
		output = v
	case []map[string]interface{}:
		if len(v) > 0 {
			output = v[0]
		} else {
			ctx.GetLogger().Warnf("Get empty data %v, just return", data)
			return nil
		}
	}

	bp, err := client.NewBatchPoints(client.BatchPointsConfig{
		Database:  m.databaseName,
		Precision: "ns",
	})
	if err != nil {
		logger.Debug(err)
		return err
	}
	tags := map[string]string{m.tagKey: m.tagValue}
	m.fieldMap = output

	pt, err := client.NewPoint(m.measurement, tags, m.fieldMap, time.Now())
	if err != nil {
		logger.Debug(err)
		return err
	}
	bp.AddPoint(pt)
	err = m.cli.Write(bp)
	if err != nil {
		logger.Debug(err)
		return err
	}
	logger.Debug("insert success")

	return nil
}

func (m *influxSink) Close(ctx api.StreamContext) error {
	m.cli.Close()
	return nil
}

func Influx() api.Sink {
	return &influxSink{}
}