package service

import (
	"fmt"
	"log"
	"me-fit/utils"
	"net/smtp"
	"os"
)

type ServiceMail interface {
	SendMail(to string, subject string, message string) error
}

func NewServiceMail() ServiceMail {
	enabled := os.Getenv("SMTP_ENABLED") == "true"
	host := os.Getenv("SMTP_HOST")
	port := os.Getenv("SMTP_PORT")
	user := os.Getenv("SMTP_USER")
	pass := os.Getenv("SMTP_PASS")
	fromMail := os.Getenv("SMTP_FROM_MAIL")
	fromName := os.Getenv("SMTP_FROM_NAME")

	if enabled {
		if host == "" {
			log.Fatal("SMTP_HOST must be set")
		}
		if port == "" {
			log.Fatal("SMTP_PORT must be set")
		}
		if user == "" {
			log.Fatal("SMTP_USER must be set")
		}
		if pass == "" {
			log.Fatal("SMTP_PASS must be set")
		}
		if fromMail == "" {
			log.Fatal("SMTP_FROM_MAIL must be set")
		}
		if fromName == "" {
			log.Fatal("SMTP_FROM_NAME must be set")
		}

		return NewServiceMailSmtp(host, port, user, pass, fromMail, fromName)
	} else {
		if utils.Environment == "prod" {
			log.Fatal("SMTP_ENABLED must be set to true in production")
		}
		return NewServiceMailStub()
	}
}

type ServiceMailSmtp struct {
	host     string
	port     string
	auth     smtp.Auth
	fromMail string
	fromName string
}

func NewServiceMailSmtp(
	host string,
	port string,
	user string,
	pass string,
	fromMail string,
	fromName string) ServiceMailSmtp {
	return ServiceMailSmtp{
		host:     host,
		port:     port,
		auth:     smtp.PlainAuth("", user, pass, host),
		fromMail: fromMail,
		fromName: fromName,
	}
}

func (service ServiceMailSmtp) SendMail(to string, subject string, message string) error {

	msg := fmt.Sprintf("From: %v <%v>\nTo: %v\nSubject: %v\nMIME-version: 1.0;\nContent-Type: text/html; charset=\"UTF-8\";\n\n%v", service.fromName, service.fromMail, to, subject, message)

	return smtp.SendMail(service.host+":"+service.port, service.auth, service.fromMail, []string{to}, []byte(msg))
}

type ServiceMailStub struct {
}

func NewServiceMailStub() ServiceMailStub {
	return ServiceMailStub{}
}

func (service ServiceMailStub) SendMail(to string, subject string, message string) error {
	return nil
}