package mail

import (
	"fmt"
	"log"
	"net/smtp"
	"strings"

	"wedding-server/internal/config"
	"wedding-server/internal/store"
)

type Mailer struct {
	cfg config.EmailConfig
}

func New(cfg config.EmailConfig) *Mailer {
	return &Mailer{cfg: cfg}
}

func (m *Mailer) send(subject, body string) error {
	if m.cfg.SMTPHost == "" {
		log.Printf("mail: SMTP not configured, skipping email %q", subject)
		return nil
	}

	addr := fmt.Sprintf("%s:%d", m.cfg.SMTPHost, m.cfg.SMTPPort)
	auth := smtp.PlainAuth("", m.cfg.SMTPUser, m.cfg.SMTPPass, m.cfg.SMTPHost)

	msg := fmt.Sprintf(
		"From: %s\r\nTo: %s\r\nSubject: %s\r\nContent-Type: text/plain; charset=UTF-8\r\n\r\n%s",
		m.cfg.From, m.cfg.To, subject, body,
	)

	return smtp.SendMail(addr, auth, m.cfg.From, []string{m.cfg.To}, []byte(msg))
}

func (m *Mailer) SendRSVP(r store.RSVP) error {
	names := make([]string, len(r.Guests))
	adults, children := 0, 0
	for i, g := range r.Guests {
		if g.IsChild {
			names[i] = g.Name + " (child)"
			children++
		} else {
			names[i] = g.Name
			adults++
		}
	}
	joined := strings.Join(names, ", ")

	var b strings.Builder
	fmt.Fprintf(&b, "New RSVP for %d guest(s) — %d adult(s), %d child(ren): %s\n", len(r.Guests), adults, children, joined)
	if r.Message != "" {
		fmt.Fprintf(&b, "\nMessage:\n%s\n", r.Message)
	}
	return m.send(fmt.Sprintf("RSVP from %s", joined), b.String())
}

func (m *Mailer) SendPhotoUpload(u store.PhotoUpload, files []store.PhotoFile) error {
	var b strings.Builder
	fmt.Fprintf(&b, "%s uploaded %d photo(s)\n\n", u.Name, len(files))
	if u.Email != "" {
		fmt.Fprintf(&b, "Email: %s\n", u.Email)
	}
	if u.Phone != "" {
		fmt.Fprintf(&b, "Phone: %s\n", u.Phone)
	}
	if u.Message != "" {
		fmt.Fprintf(&b, "\nMessage:\n%s\n", u.Message)
	}
	b.WriteString("\nPhotos:\n")
	for _, f := range files {
		fmt.Fprintf(&b, "- %s\n", f.URL)
	}
	return m.send(fmt.Sprintf("%s uploaded photos", u.Name), b.String())
}