package prometheusctl

import (
	"errors"
	"flag"
	"fmt"
	"time"

	"github.com/peterbourgon/ff/v3"

	"edge-infra.dev/pkg/edge/constants/api/cluster"
	"edge-infra.dev/pkg/k8s/meta"
)

type config struct {
	prometheus        meta.NamespacedObjectReference
	reconcileInterval time.Duration
	clusterProvider   string
}

// validate checks all env variable fields are present
func (cfg *config) validate() error {
	if cfg.prometheus.Name == "" {
		return errors.New("--prometheus-name must be provided")
	}
	if cfg.prometheus.Namespace == "" {
		return errors.New("--prometheus-namespace must be provided")
	}

	return nil
}

// NewConfig creates a new config and flagset from os args
func newConfig(args []string) (*config, error) {
	cfg := &config{}

	fs := flag.NewFlagSet("prometheus-stackdriver", flag.ContinueOnError)
	fs.StringVar(&cfg.prometheus.Name, "prometheus-name", "prometheus",
		"name of prometheus object to reconcile")
	fs.StringVar(&cfg.prometheus.Namespace, "prometheus-namespace", "prometheus",
		"namespace of prometheus object to reconcile")
	fs.DurationVar(&cfg.reconcileInterval, "reconcile-interval", time.Second*60,
		"how often to re-reconcile when an error occurs")
	fs.StringVar(&cfg.clusterProvider, "cluster-provider", string(cluster.Generic),
		fmt.Sprintf("K8s cluster provider: %s. Takes precedence over other provider flags.", cluster.Types))

	if err := ff.Parse(fs, args[1:], ff.WithEnvVarNoPrefix()); err != nil {
		return nil, err
	}

	if err := cfg.validate(); err != nil {
		return nil, err
	}

	return cfg, nil
}