package clients

import (
	"bytes"
	"fmt"
	"gitea.pena/PenaSide/notifier/internal/initialize"
	"github.com/gofiber/fiber/v2"
	"go.uber.org/zap"
	"html/template"
	"mime/multipart"
)

type MailClient struct {
	smtpApiUrl  string
	smtpSender  string
	apiKey      string
	fiberClient *fiber.Client
	logger      *zap.Logger
}

func NewMailClient(deps initialize.MailClientCfg) *MailClient {
	if deps.FiberClient == nil {
		deps.FiberClient = fiber.AcquireClient()
	}
	return &MailClient{
		smtpApiUrl:  deps.ApiURL,
		smtpSender:  deps.Sender,
		apiKey:      deps.ApiKey,
		fiberClient: deps.FiberClient,
		logger:      deps.Logger,
	}
}

type SenderDeps struct {
	Subject string
	Email   string
	Tmpl    string
}

func (m *MailClient) MailSender(data SenderDeps) error {
	tmpl, err := template.New("email").Parse(data.Tmpl)
	if err != nil {
		m.logger.Error("Error parsing HTML template:", zap.Error(err))
		return err
	}

	var buf bytes.Buffer
	if err = tmpl.Execute(&buf, nil); err != nil {
		m.logger.Error("Error executing template:", zap.Error(err))
		return err
	}

	htmlBody := buf.String()

	form := new(bytes.Buffer)
	writer := multipart.NewWriter(form)

	fields := map[string]string{
		"from":    m.smtpSender,
		"to":      data.Email,
		"subject": data.Subject,
		"html":    htmlBody,
	}

	for key, value := range fields {
		if err = writer.WriteField(key, value); err != nil {
			return err
		}
	}

	if err = writer.Close(); err != nil {
		return err
	}

	req := m.fiberClient.Post(m.smtpApiUrl).Body(form.Bytes()).ContentType(writer.FormDataContentType())
	if m.apiKey != "" {
		req.Set("Authorization", m.apiKey)
	}

	statusCode, body, errs := req.Bytes()
	if errs != nil {
		m.logger.Error("Error sending request:", zap.Error(errs[0]))
		return errs[0]
	}

	if statusCode != fiber.StatusOK {
		err = fmt.Errorf("the SMTP service returned an error: %s Response body: %s", statusCode, body)
		m.logger.Error("Error sending email:", zap.Error(err))
		return err
	}

	return nil
}