// Package database define database operation functions
package database

import (
	"fmt"
	"strings"
)

// QueryPara define struct of influxdb query parameters
type InfluxDBQueryPara struct {
	Bucket      string `json:"bucket"`
	Measurement string `json:"measurement"`
	Start       string `json:"start"`
	Stop        string `json:"stop"`
	Field       string `json:"field"`
	// Value       float64 `json:"value"`
}

type QueryPara interface {
	apply(string) string
}

type BucketQueryPara string

func (b BucketQueryPara) apply(query string) string {
	template := " from(bucket:\"{bucketId}\") "
	template = strings.Replace(template, "{bucketId}", string(b), -1)
	return query + template
}

func WithBucket(bucketID string) BucketQueryPara {
	return BucketQueryPara(bucketID)
}

type MeasurementQueryPara string

func (m MeasurementQueryPara) apply(query string) string {
	template := " |> filter(fn: (r) => r[\"_measurement\"] == \"{measurement}\") "
	template = strings.Replace(template, "{measurement}", string(m), -1)
	return query + template
}

func WithMeasurement(measurement string) MeasurementQueryPara {
	return MeasurementQueryPara(measurement)
}

type StartTimeQueryPara string

func (s StartTimeQueryPara) apply(query string) string {
	template := " |> range(start: {start}) "
	template = strings.Replace(template, "{start}", string(s), -1)
	return query + template
}

func WithStartTime(measurement string) StartTimeQueryPara {
	return StartTimeQueryPara(measurement)
}

func InitQueryByPara(paras ...QueryPara) (queryCmd string) {
	for _, para := range paras {
		queryCmd = para.apply(queryCmd)
	}
	fmt.Printf("queryCmd:%v\n", queryCmd)
	return
}