package main

import (
	"bytes"
	"io"
	"log"
	"mime"

	"github.com/emersion/go-imap/v2"
	"github.com/emersion/go-imap/v2/imapclient"
	"github.com/emersion/go-message/charset"
	"github.com/emersion/go-message/mail"
)

type MailBox struct {
	Server   string
	User     string
	Password string
	InBox    string
	Client   *imapclient.Client
}

func (mb *MailBox) ListMessages() (string, error) {
	return "", nil
}

func (mb *MailBox) Connect() error {
	options := &imapclient.Options{
		WordDecoder: &mime.WordDecoder{CharsetReader: charset.Reader},
	}
	var err error
	mb.Client, err = imapclient.DialTLS(mb.Server, options)
	if err != nil {
		log.Println("Error connnecting to", mb.Server, ":", err)
		return err
	}
	log.Println("Connected")
	err = mb.Client.Login(mb.User, mb.Password).Wait()
	if err != nil {
		log.Fatal("failed to login:", err)
	}
	log.Println("Logged in")

	mailBoxes, err := mb.Client.List("", "%", nil).Collect()
	if err != nil {
		log.Fatal("Error listing mailboxes", err)
	}
	for _, mbox := range mailBoxes {
		log.Println("mailbox:", mbox.Mailbox)
	}
	inbox, err := mb.Client.Select(mb.InBox, nil).Wait()
	if err != nil {
		log.Fatal("Error selecting mailbox:", mb.InBox, err)
	}
	log.Println("Inbox has", inbox.NumMessages, "messages")

	for i := uint32(0); i <= inbox.NumMessages; i++ {
		seqSet := imap.SeqSetNum(i)
		bodySection := &imap.FetchItemBodySection{}
		fetchOptions := &imap.FetchOptions{
			Envelope:    true,
			BodySection: []*imap.FetchItemBodySection{bodySection},
		}
		messages, err := mb.Client.Fetch(seqSet, fetchOptions).Collect()
		if err != nil {
			log.Fatal("Error fetching mails:", err)
		}
		for _, msg := range messages {
			log.Println(msg.Envelope.From)
			log.Println(msg.Envelope.To)
			log.Println(msg.Envelope.Date)
			log.Println(msg.Envelope.Subject)

			section := msg.FindBodySection(bodySection)
			ioReader := bytes.NewReader(section)
			mailReader, err := mail.CreateReader(ioReader)
			if err != nil {
				log.Fatalf("failed to create mail reader: %v", err)
			}
			for {
				part, err := mailReader.NextPart()
				if err == io.EOF {
					log.Println("------------")
					break
				} else if err != nil {
					log.Fatal("Error reading part", err)
				}
				switch header := part.Header.(type) {
				case *mail.AttachmentHeader:
					filename, _ := header.Filename()
					log.Println("Attachment:", filename)
				case *mail.InlineHeader:
					body, _ := io.ReadAll(part.Body)
					log.Println(string(body))
				}
			}
		}
	}
	return nil
}

func (mb *MailBox) Close() {
	mb.Client.Close()
}