appview: state: validate pasted patch

appview/state/pull.go

···
 		sourceBranch := r.FormValue("sourceBranch")
 		patch := r.FormValue("patch")
 
-		// Validate required fields for all PR types
-		if title == "" || body == "" || targetBranch == "" {
-			s.pages.Notice(w, "pull", "Title, body and target branch are required.")
+		if targetBranch == "" {
+			s.pages.Notice(w, "pull", "Target branch is required.")
 			return
 		}
 
 		us, err := NewUnsignedClient(f.Knot, s.config.Dev)
 		if err != nil {
-			log.Println("failed to create unsigned client to %s: %v", f.Knot, err)
+			log.Printf("failed to create unsigned client to %s: %v", f.Knot, err)
 			s.pages.Notice(w, "pull", "Failed to create a pull request. Try again later.")
 			return
 		}
···
 	}
 
 	s.pages.HxLocation(w, fmt.Sprintf("/%s/pulls/%d", f.OwnerSlashRepo(), pullId))
+}
+
+func (s *State) ValidatePatch(w http.ResponseWriter, r *http.Request) {
+	_, err := fullyResolvedRepo(r)
+	if err != nil {
+		log.Println("failed to get repo and knot", err)
+		return
+	}
+
+	patch := r.FormValue("patch")
+	if patch == "" {
+		s.pages.Notice(w, "patch-error", "Patch is required.")
+		return
+	}
+
+	if patch == "" || !patchutil.IsPatchValid(patch) {
+		s.pages.Notice(w, "patch-error", "Invalid patch format. Please provide a valid git diff or format-patch.")
+		return
+	}
+
+	if patchutil.IsFormatPatch(patch) {
+		s.pages.Notice(w, "patch-preview", "Format patch detected. Title and description are optional; if left out, they will be extracted from the first commit.")
+	} else {
+		s.pages.Notice(w, "patch-preview", "Regular diff detected. Please provide a title and description.")
+	}
 }
 
 func (s *State) PatchUploadFragment(w http.ResponseWriter, r *http.Request) {

appview/state/router.go

···
 				r.With(AuthMiddleware(s)).Route("/new", func(r chi.Router) {
 					r.Get("/", s.NewPull)
 					r.Get("/patch-upload", s.PatchUploadFragment)
+					r.Post("/validate-patch", s.ValidatePatch)
 					r.Get("/compare-branches", s.CompareBranchesFragment)
 					r.Get("/compare-forks", s.CompareForksFragment)
 					r.Get("/fork-branches", s.CompareForksBranchesFragment)

input.css

···
             font-size: 15px;
         }
         @supports (font-variation-settings: normal) {
-          html {
-            font-feature-settings: 'ss01' 1, 'kern' 1, 'liga' 1, 'cv05' 1, 'tnum' 1;
-          }
+            html {
+                font-feature-settings:
+                    "ss01" 1,
+                    "kern" 1,
+                    "liga" 1,
+                    "cv05" 1,
+                    "tnum" 1;
+            }
         }
 
         a {
···
             @apply block mb-2 text-gray-900 text-sm font-bold py-2 uppercase dark:text-gray-100;
         }
         input {
-            @apply bg-white border border-gray-400 rounded-sm focus:ring-black p-3 dark:bg-gray-800 dark:border-gray-600 dark:text-white dark:focus:ring-gray-400;
+            @apply border border-gray-400 block rounded bg-gray-50 focus:ring-black p-3 dark:bg-gray-800 dark:border-gray-600 dark:text-white dark:focus:ring-gray-400;
         }
         textarea {
-            @apply bg-white border border-gray-400 rounded-sm focus:ring-black p-3 dark:bg-gray-800 dark:border-gray-600 dark:text-white dark:focus:ring-gray-400;
+            @apply border border-gray-400 block rounded bg-gray-50 focus:ring-black p-3 dark:bg-gray-800 dark:border-gray-600 dark:text-white dark:focus:ring-gray-400;
         }
         details summary::-webkit-details-marker {
             display: none;

patchutil/patchutil.go

···
 			strings.HasPrefix(line, "commit ") {
 			headerCount++
 		}
-		if strings.HasPrefix(line, "diff --git ") {
-			return true
-		}
 	}
 
 	return headerCount >= 2