View switching feature

main.go

@@ -256,9 +256,10 @@ func (h *handler) serveDir(w http.ResponseWriter, r *http.Request, urlPath, fsPa
 		rendered = renderMarkdown(rawMD)
 	}
 
+	view, sortKey, order := readPageSettings(fsPath).viewSettings()
 	var entries []entry
 	if !editMode && (special == nil || !special.SuppressListing) {
-		entries = listEntries(fsPath, urlPath)
+		entries = listEntries(fsPath, urlPath, sortKey, order)
 	}
 
 	title := pageTitle(urlPath)
@@ -312,6 +313,9 @@ func (h *handler) serveDir(w http.ResponseWriter, r *http.Request, urlPath, fsPa
 		RawContent:     rawContent,
 		Content:        rendered,
 		Entries:        entries,
+		View:           view,
+		Sort:           sortKey,
+		Order:          order,
 		SpecialContent: specialContent,
 		SidebarWidget:  sidebarWidget,
 		SuppressTOC:    suppressTOC,
@@ -354,6 +358,10 @@ func (h *handler) handlePost(w http.ResponseWriter, r *http.Request, urlPath, fs
 		h.handleAddTask(w, r, urlPath, fsPath)
 		return
 	}
+	if query.Has("settings") {
+		h.handleSettings(w, r, urlPath, fsPath)
+		return
+	}
 
 	if err := r.ParseForm(); err != nil {
 		http.Error(w, "bad request", http.StatusBadRequest)
@@ -447,7 +455,8 @@ func readPageSettings(dir string) *pageSettings {
 	if err != nil {
 		return nil
 	}
-	s := &pageSettings{}
+	// Defaults; overridden only by valid values present in the file.
+	s := &pageSettings{View: viewList, Sort: sortName, Order: orderAsc}
 	for _, line := range strings.Split(string(data), "\n") {
 		line = strings.TrimSpace(line)
 		if line == "" || strings.HasPrefix(line, "#") {
@@ -457,9 +466,16 @@ func readPageSettings(dir string) *pageSettings {
 		if len(parts) != 2 {
 			continue
 		}
+		value := strings.TrimSpace(parts[1])
 		switch strings.TrimSpace(parts[0]) {
 		case "type":
-			s.Type = strings.TrimSpace(parts[1])
+			s.Type = value
+		case "view":
+			s.View = validateView(value)
+		case "sort":
+			s.Sort = validateSort(value)
+		case "order":
+			s.Order = validateOrder(value)
 		}
 	}
 	return s