1 files changed, 44 insertions, 3 deletions

diff --git a/internal/web/handlers_design.go b/internal/web/handlers_design.go
index 601ba34..0db66c2 100644
--- a/internal/web/handlers_design.go
+++ b/internal/web/handlers_design.go
@@ -2,12 +2,14 @@ package web
 
 import (
 	"bytes"
+	"encoding/json"
 	"errors"
 	"io"
 	"mime/multipart"
 	"net/http"
 	"path/filepath"
 	"strconv"
+	"strings"
 
 	"github.com/google/uuid"
 	"github.com/gramanas/blogspace/internal/store"
@@ -89,6 +91,24 @@ func (s *Server) storeUpload(r *http.Request, fh *multipart.FileHeader) (*store.
 	return s.st.CreateImage(r.Context(), currentBlog(r).ID, name, ct, buf.Bytes())
 }
 
+// imageMarkdown is the line the editor inserts for an uploaded image.
+func imageMarkdown(img *store.Image) string {
+	return "![" + strings.NewReplacer("]", "", "\n", " ").Replace(img.Filename) + "](/media/" + img.ID.String() + ")"
+}
+
+// appendImageMD is the no-JavaScript path of "Insert image": the file arrives
+// with the form itself and is appended to the end of the text on save.
+func appendImageMD(md string, img *store.Image) string {
+	if img == nil {
+		return md
+	}
+	md = strings.TrimRight(md, "\n")
+	if md != "" {
+		md += "\n\n"
+	}
+	return md + imageMarkdown(img) + "\n"
+}
+
 func kbString(n int64) string {
 	if n >= 1<<20 {
 		return strconv.FormatInt(n>>20, 10) + " MB"
@@ -107,24 +127,45 @@ func (s *Server) handleImages(w http.ResponseWriter, r *http.Request) {
 	s.render(w, r, "dashboard/images.html", map[string]any{"images": images})
 }
 
+// handleImageUpload serves the Images page form and, when the client asks for
+// JSON, the editor's "Insert image" script.
 func (s *Server) handleImageUpload(w http.ResponseWriter, r *http.Request) {
 	blog := currentBlog(r)
+	wantJSON := strings.Contains(r.Header.Get("Accept"), "application/json")
+	fail := func(msg string) {
+		if wantJSON {
+			writeJSON(w, http.StatusBadRequest, map[string]string{"error": msg})
+			return
+		}
+		s.plainError(w, http.StatusBadRequest, msg)
+	}
 	if err := r.ParseMultipartForm(1 << 20); err != nil {
-		s.plainError(w, http.StatusBadRequest, "Upload too large or malformed form.")
+		fail("Upload too large or malformed form.")
 		return
 	}
 	img, err := s.readUpload(r, "file")
 	if err != nil {
-		s.plainError(w, http.StatusBadRequest, err.Error())
+		fail(err.Error())
 		return
 	}
 	if img == nil {
-		s.plainError(w, http.StatusBadRequest, "Choose a file first.")
+		fail("Choose a file first.")
+		return
+	}
+	if wantJSON {
+		writeJSON(w, http.StatusOK, map[string]string{"id": img.ID.String(), "filename": img.Filename, "markdown": imageMarkdown(img)})
 		return
 	}
 	redirectOK(w, r, "/b/"+blog.Subdomain+"/images", "Uploaded "+img.Filename+".")
 }
 
+func writeJSON(w http.ResponseWriter, status int, v any) {
+	w.Header().Set("Content-Type", "application/json")
+	w.Header().Set("X-Content-Type-Options", "nosniff")
+	w.WriteHeader(status)
+	_ = json.NewEncoder(w).Encode(v)
+}
+
 func (s *Server) handleImageDelete(w http.ResponseWriter, r *http.Request) {
 	blog := currentBlog(r)
 	id, err := uuid.Parse(r.PathValue("id"))