// Package cssl provides functionality.
package cssl

import (
	"log"
	"net/http"
	"net/url"
	"time"

	"github.com/pkg/errors"

	"rocketgit.ru/rsmon/worker/app/models"
)

var client *http.Client

func init() {
	client = &http.Client{
		Timeout: time.Second * 60,
		CheckRedirect: func(_ *http.Request, _ []*http.Request) error {
			return http.ErrUseLastResponse
		},
	}
}

// Perform provides functionality.
func Perform(c *models.Check) *Result {
	result := &Result{}
	result.State = "OK"

	var ur string
	if c.URL != nil && *c.URL != "" {
		ur = *c.URL

		u, err := url.Parse(ur)
		if err != nil {
			result.State = "FAIL"
			result.Error = errors.Wrap(err, "bad url")
			return result
		}
		u.Scheme = "https"
		ur = u.String()
	} else {
		ur = "https://" + c.Monitor.Host
	}
	log.Println("URL:", ur)
	reqest, err := http.NewRequest("GET", ur, http.NoBody)
	if err != nil {
		result.State = "FAIL"
		result.Error = err
		return result
	}

	reqest.Header.Set("Cache-Control", "max-age=0")
	reqest.Header.Set("Connection", "close")
	resp, err := client.Do(reqest)
	if err != nil {
		result.State = "ERR"
		result.Error = errors.Wrap(err, "https request error")
		return result
	}
	defer resp.Body.Close() //nolint:errcheck

	if resp.TLS == nil {
		result.State = "ERR"
		result.Error = errors.New("bad SSL cert CN")
	} else {
		cert := resp.TLS.VerifiedChains[0][0]
		result.Expires = &cert.NotAfter
		exp := time.Until(*result.Expires).Hours() / 24

		if exp < 2 {
			result.State = "WARN"
			result.Warnings = append(result.Warnings, "Certificate expires soon")
		}
	}

	return result
}