package prospector

import (
	"fmt"
	"time"

	cfg "github.com/elastic/beats/filebeat/config"
	"github.com/elastic/beats/libbeat/common/match"
)

var (
	defaultConfig = prospectorConfig{
		Enabled:        true,
		IgnoreOlder:    0,
		ScanFrequency:  10 * time.Second,
		InputType:      cfg.DefaultInputType,
		CleanInactive:  0,
		CleanRemoved:   true,
		HarvesterLimit: 0,
		Symlinks:       false,
		TailFiles:      false,
	}
)

type prospectorConfig struct {
	Enabled        bool            `config:"enabled"`
	ExcludeFiles   []match.Matcher `config:"exclude_files"`
	IgnoreOlder    time.Duration   `config:"ignore_older"`
	Paths          []string        `config:"paths"`
	ScanFrequency  time.Duration   `config:"scan_frequency" validate:"min=0,nonzero"`
	InputType      string          `config:"input_type"`
	CleanInactive  time.Duration   `config:"clean_inactive" validate:"min=0"`
	CleanRemoved   bool            `config:"clean_removed"`
	HarvesterLimit uint64          `config:"harvester_limit" validate:"min=0"`
	Symlinks       bool            `config:"symlinks"`
	TailFiles      bool            `config:"tail_files"`
}

func (config *prospectorConfig) Validate() error {

	if config.InputType == cfg.LogInputType && len(config.Paths) == 0 {
		return fmt.Errorf("No paths were defined for prospector")
	}

	if config.CleanInactive != 0 && config.IgnoreOlder == 0 {
		return fmt.Errorf("ignore_older must be enabled when clean_inactive is used.")
	}

	if config.CleanInactive != 0 && config.CleanInactive <= config.IgnoreOlder+config.ScanFrequency {
		return fmt.Errorf("clean_inactive must be > ignore_older + scan_frequency to make sure only files which are not monitored anymore are removed.")
	}

	return nil
}