package main
  
import (
	//"reflect"
    "bytes"
    "fmt"
    "text/template"
)

//----------------------------------------------
// params: class, bucket, varname=default _DATA
// %s => bucket tmplate value
// %s => ifcond
// %s => bucket value
//----------------------------------------------

//https://stackoverflow.com/questions/22367337/last-item-in-a-template-range

type RuleStru struct{

    Class 			string
    Bucket 			string
	VarName			string
	
	NickName		string
	PrintID			string
	PrintAtTime		string
	SnmpResult		[]string   // snmpResult0, ...
	TmplIndex		[]string   // {{index .value 0}} , ...
}


//-------------------------------------------------------------------------------------------------
// bucket2rule -class "class1, class2" -tmpl "myrule.tmpl" -type "etcd"/"file"  -out "/opt/syslog"
//-------------------------------------------------------------------------------------------------

func main() {

	myrule := `{{$VAR := .VarName}}
--class = {{.Class}}
--parser = json
--fields = {{.VarName}}
--mqltmpl= insert into {{.Class}} (id, {{.Bucket}}) values ('{{.PrintID}}', [{{range $i, $e := .TmplIndex}} {{if $i}},{{end}} {{.}} {{end}}]) at '{{.PrintAtTime}}'
--ignore = false

log.info("{{.Bucket}}_{{.NickName}} start...")

if {{range  $i, $e := .SnmpResult}} {{if $i}} AND {{end}} {{$VAR}}["{{.}}"] ~= nil {{end}} then
	_id	= "{{.NickName}}:" ..{{.VarName}}["IPaddress"]
	_values = { {{range  $i, $e := .SnmpResult}} {{if $i}}, {{end}} {{$VAR}}["{{.}}"] {{end}} }
	_attime = {{.VarName}}["tasktime"]
else
	_IGNORE = true
end
`

    rs := RuleStru{Class: "/matrix/devops/node", Bucket: "cpu_perf", VarName: "_DATA", NickName: "node", PrintID: `{{.id}}`, PrintAtTime:`{{.attime}}`, SnmpResult: []string{"snmpResult0", "snmpResult1"} , TmplIndex: []string{`{{index .value 0}}`, `{{index .value 1}}`}}
    
	t := template.Must(template.New("abc").Parse(myrule))
      
    buf := &bytes.Buffer{}
    if err := t.Execute(buf, rs) ; err != nil {
		fmt.Println(err)
	}else{
		fmt.Println( buf.String() )
	}
}