feat: markdown for html bodies

backend/backend.go

@@ -27,7 +27,9 @@ type Provider interface {
 // EmailReader fetches emails and their content.
 type EmailReader interface {
 	FetchEmails(ctx context.Context, folder string, limit, offset uint32) ([]Email, error)
-	FetchEmailBody(ctx context.Context, folder string, uid uint32) (string, []Attachment, error)
+	// FetchEmailBody returns the chosen body, its MIME type ("text/html" or
+	// "text/plain"; empty when unknown), parsed attachments, and any error.
+	FetchEmailBody(ctx context.Context, folder string, uid uint32) (string, string, []Attachment, error)
 	FetchAttachment(ctx context.Context, folder string, uid uint32, partID, encoding string) ([]byte, error)
 }
 

backend/imap/imap.go

@@ -36,12 +36,12 @@ func (p *Provider) FetchEmails(_ context.Context, folder string, limit, offset u
 	return toBackendEmails(emails), nil
 }
 
-func (p *Provider) FetchEmailBody(_ context.Context, folder string, uid uint32) (string, []backend.Attachment, error) {
-	body, atts, err := fetcher.FetchEmailBodyFromMailbox(p.account, folder, uid)
+func (p *Provider) FetchEmailBody(_ context.Context, folder string, uid uint32) (string, string, []backend.Attachment, error) {
+	body, mimeType, atts, err := fetcher.FetchEmailBodyFromMailbox(p.account, folder, uid)
 	if err != nil {
-		return "", nil, err
+		return "", "", nil, err
 	}
-	return body, toBackendAttachments(atts), nil
+	return body, mimeType, toBackendAttachments(atts), nil
 }
 
 func (p *Provider) FetchAttachment(_ context.Context, folder string, uid uint32, partID, encoding string) ([]byte, error) {

backend/jmap/jmap.go

@@ -276,10 +276,10 @@ func searchLimit(query backend.SearchQuery) uint32 {
 	return 100
 }
 
-func (p *Provider) FetchEmailBody(_ context.Context, _ string, uid uint32) (string, []backend.Attachment, error) {
+func (p *Provider) FetchEmailBody(_ context.Context, _ string, uid uint32) (string, string, []backend.Attachment, error) {
 	jmapID, err := p.lookupJMAPID(uid)
 	if err != nil {
-		return "", nil, err
+		return "", "", nil, err
 	}
 
 	req := &jmapclient.Request{}
@@ -297,25 +297,27 @@ func (p *Provider) FetchEmailBody(_ context.Context, _ string, uid uint32) (stri
 
 	resp, err := p.client.Do(req)
 	if err != nil {
-		return "", nil, fmt.Errorf("jmap body: %w", err)
+		return "", "", nil, fmt.Errorf("jmap body: %w", err)
 	}
 
 	for _, inv := range resp.Responses {
 		if r, ok := inv.Args.(*email.GetResponse); ok && len(r.List) > 0 {
 			eml := r.List[0]
 
 			// Get body text (prefer HTML)
-			var body string
+			var body, mimeType string
 			for _, part := range eml.HTMLBody {
 				if val, ok := eml.BodyValues[part.PartID]; ok {
 					body = val.Value
+					mimeType = "text/html"
 					break
 				}
 			}
 			if body == "" {
 				for _, part := range eml.TextBody {
 					if val, ok := eml.BodyValues[part.PartID]; ok {
 						body = val.Value
+						mimeType = "text/plain"
 						break
 					}
 				}
@@ -336,11 +338,11 @@ func (p *Provider) FetchEmailBody(_ context.Context, _ string, uid uint32) (stri
 				atts = append(atts, a)
 			}
 
-			return body, atts, nil
+			return body, mimeType, atts, nil
 		}
 	}
 
-	return "", nil, fmt.Errorf("jmap: email not found")
+	return "", "", nil, fmt.Errorf("jmap: email not found")
 }
 
 func (p *Provider) FetchAttachment(_ context.Context, _ string, _ uint32, partID, _ string) ([]byte, error) {

backend/pop3/pop3.go

@@ -131,21 +131,21 @@ func (p *Provider) FetchEmails(_ context.Context, _ string, limit, offset uint32
 	return emails, nil
 }
 
-func (p *Provider) FetchEmailBody(_ context.Context, _ string, uid uint32) (string, []backend.Attachment, error) {
+func (p *Provider) FetchEmailBody(_ context.Context, _ string, uid uint32) (string, string, []backend.Attachment, error) {
 	conn, err := p.connect()
 	if err != nil {
-		return "", nil, err
+		return "", "", nil, err
 	}
 	defer conn.Quit()
 
 	msgID, err := p.findMessageByUID(conn, uid)
 	if err != nil {
-		return "", nil, err
+		return "", "", nil, err
 	}
 
 	raw, err := conn.RetrRaw(msgID)
 	if err != nil {
-		return "", nil, fmt.Errorf("pop3 retr: %w", err)
+		return "", "", nil, fmt.Errorf("pop3 retr: %w", err)
 	}
 
 	return parseMessageBody(raw)
@@ -352,15 +352,17 @@ func entityToEmail(header *message.Header, msgInfo pop3client.MessageID, account
 }
 
 // parseMessageBody extracts the body text and attachments from a raw message.
-func parseMessageBody(r io.Reader) (string, []backend.Attachment, error) {
+func parseMessageBody(r io.Reader) (string, string, []backend.Attachment, error) {
 	mr, err := gomail.CreateReader(r)
 	if err != nil {
-		// Not a multipart message — read body directly
+		// Not a multipart message — read body directly. We don't know the
+		// content type at this layer; surface empty so the renderer falls
+		// back to its legacy markdown→HTML path.
 		body, err := io.ReadAll(r)
 		if err != nil {
-			return "", nil, err
+			return "", "", nil, err
 		}
-		return string(body), nil, nil
+		return string(body), "", nil, nil
 	}
 
 	var bodyText string
@@ -411,9 +413,9 @@ func parseMessageBody(r io.Reader) (string, []backend.Attachment, error) {
 	}
 
 	if htmlBody != "" {
-		return htmlBody, attachments, nil
+		return htmlBody, "text/html", attachments, nil
 	}
-	return bodyText, attachments, nil
+	return bodyText, "text/plain", attachments, nil
 }
 
 // findAttachmentData walks a raw message to find attachment data by partID.

config/cache.go

@@ -425,6 +425,7 @@ type CachedEmailBody struct {
 	UID            uint32             `json:"uid"`
 	AccountID      string             `json:"account_id"`
 	Body           string             `json:"body"`
+	BodyMIMEType   string             `json:"body_mime_type,omitempty"` // empty for cache rows written before MIME-type tracking; renderer falls back to legacy markdown→HTML pre-pass
 	Attachments    []CachedAttachment `json:"attachments,omitempty"`
 	CachedAt       time.Time          `json:"cached_at"`
 	LastAccessedAt time.Time          `json:"last_accessed_at"`

daemon/handler.go

@@ -154,7 +154,7 @@ func (d *Daemon) handleFetchEmailBody(conn *daemonrpc.Conn, req *daemonrpc.Reque
 	ctx, cancel := context.WithTimeout(context.Background(), fetchTimeout)
 	defer cancel()
 
-	body, attachments, err := p.FetchEmailBody(ctx, params.Folder, params.UID)
+	body, mimeType, attachments, err := p.FetchEmailBody(ctx, params.Folder, params.UID)
 	if err != nil {
 		conn.SendError(req.ID, daemonrpc.ErrCodeInternal, err.Error())
 		return
@@ -172,8 +172,9 @@ func (d *Daemon) handleFetchEmailBody(conn *daemonrpc.Conn, req *daemonrpc.Reque
 	}
 
 	conn.SendResponse(req.ID, daemonrpc.FetchEmailBodyResult{
-		Body:        body,
-		Attachments: attInfos,
+		Body:         body,
+		BodyMIMEType: mimeType,
+		Attachments:  attInfos,
 	})
 }
 

daemonclient/service.go

@@ -16,7 +16,9 @@ import (
 // TUI and CLI use this interface — they don't care which mode is active.
 type Service interface {
 	FetchEmails(accountID, folder string, limit, offset uint32) ([]backend.Email, error)
-	FetchEmailBody(accountID, folder string, uid uint32) (string, []backend.Attachment, error)
+	// FetchEmailBody returns body, MIME type ("text/html"|"text/plain"|""),
+	// attachments, and any error.
+	FetchEmailBody(accountID, folder string, uid uint32) (string, string, []backend.Attachment, error)
 	DeleteEmails(accountID, folder string, uids []uint32) error
 	ArchiveEmails(accountID, folder string, uids []uint32) error
 	MoveEmails(accountID string, uids []uint32, src, dst string) error
@@ -102,15 +104,15 @@ func (s *daemonService) FetchEmails(accountID, folder string, limit, offset uint
 	return emails, err
 }
 
-func (s *daemonService) FetchEmailBody(accountID, folder string, uid uint32) (string, []backend.Attachment, error) {
+func (s *daemonService) FetchEmailBody(accountID, folder string, uid uint32) (string, string, []backend.Attachment, error) {
 	var result daemonrpc.FetchEmailBodyResult
 	err := s.client.Call(daemonrpc.MethodFetchEmailBody, daemonrpc.FetchEmailBodyParams{
 		AccountID: accountID,
 		Folder:    folder,
 		UID:       uid,
 	}, &result)
 	if err != nil {
-		return "", nil, err
+		return "", "", nil, err
 	}
 
 	var attachments []backend.Attachment
@@ -122,7 +124,7 @@ func (s *daemonService) FetchEmailBody(accountID, folder string, uid uint32) (st
 			MIMEType: a.MIMEType,
 		})
 	}
-	return result.Body, attachments, nil
+	return result.Body, result.BodyMIMEType, attachments, nil
 }
 
 func (s *daemonService) DeleteEmails(accountID, folder string, uids []uint32) error {
@@ -251,10 +253,10 @@ func (s *directService) FetchEmails(accountID, folder string, limit, offset uint
 	return p.FetchEmails(context.Background(), folder, limit, offset)
 }
 
-func (s *directService) FetchEmailBody(accountID, folder string, uid uint32) (string, []backend.Attachment, error) {
+func (s *directService) FetchEmailBody(accountID, folder string, uid uint32) (string, string, []backend.Attachment, error) {
 	p, err := s.getProvider(accountID)
 	if err != nil {
-		return "", nil, err
+		return "", "", nil, err
 	}
 	return p.FetchEmailBody(context.Background(), folder, uid)
 }

daemonrpc/protocol.go

@@ -147,8 +147,9 @@ type FetchEmailBodyParams struct {
 }
 
 type FetchEmailBodyResult struct {
-	Body        string           `json:"body"`
-	Attachments []AttachmentInfo `json:"attachments"`
+	Body         string           `json:"body"`
+	BodyMIMEType string           `json:"body_mime_type,omitempty"`
+	Attachments  []AttachmentInfo `json:"attachments"`
 }
 
 type AttachmentInfo struct {