package prospector

import (
	"fmt"

	"github.com/elastic/beats/filebeat/harvester"
	"github.com/elastic/beats/filebeat/input/file"
	"github.com/elastic/beats/libbeat/logp"
)

type ProspectorStdin struct {
	harvester *harvester.Harvester
	started   bool
}

// NewProspectorStdin creates a new stdin prospector
// This prospector contains one harvester which is reading from stdin
func NewProspectorStdin(p *Prospector) (*ProspectorStdin, error) {

	prospectorer := &ProspectorStdin{
		started: false,
	}

	var err error

	prospectorer.harvester, err = p.createHarvester(file.State{Source: "-"})
	if err != nil {
		return nil, fmt.Errorf("Error initializing stdin harvester: %v", err)
	}

	return prospectorer, nil
}

func (p *ProspectorStdin) LoadStates(states []file.State) error {
	return nil
}

func (p *ProspectorStdin) Run() {

	// Make sure stdin harvester is only started once
	if !p.started {
		reader, err := p.harvester.Setup()
		if err != nil {
			logp.Err("Error starting stdin harvester: %s", err)
			return
		}
		go p.harvester.Harvest(reader)
		p.started = true
	}
}