revamped left menus entirely to a new menu definition system

ui/menus.go

@@ -0,0 +1,80 @@
+/*
+ * Amsterdam Web Communities System
+ * Copyright (c) 2025 Erbosoft Metaverse Design Solutions, All Rights Reserved
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+// Package ui holds the support for the Amsterdam user interface, wrapping Echo and Jet templates.
+package ui
+
+import (
+	_ "embed"
+
+	"git.erbosoft.com/amy/amsterdam/database"
+	"gopkg.in/yaml.v3"
+)
+
+// MenuItem represents an itrem within a menu definition.
+type MenuItem struct {
+	Text       string `yaml:"text"`
+	Link       string `yaml:"link"`
+	Disabled   bool   `yaml:"disabled"`
+	Permission string `yaml:"permission"`
+	P          *MenuDefinition
+}
+
+func (mi *MenuItem) Show(ctxt AmContext) bool {
+	if mi.Permission == "" {
+		return true
+	}
+	u := ctxt.CurrentUser()
+	var eperm uint16
+	switch mi.P.PermSet {
+	case "user":
+		eperm = u.BaseLevel
+	default:
+		eperm = database.AmRole("NotInList").Level()
+	}
+	return database.AmTestPermission(mi.Permission, eperm)
+}
+
+// MenuDefinition represents a full menu definition.
+type MenuDefinition struct {
+	ID      string     `yaml:"id"`
+	Title   string     `yaml:"title"`
+	PermSet string     `yaml:"permSet"`
+	Items   []MenuItem `yaml:"items"`
+}
+
+// MenuDefs represents the set of all menu definitions.
+type MenuDefs struct {
+	D     []MenuDefinition `yaml:"menudefs"`
+	table map[string]*MenuDefinition
+}
+
+//go:embed menudefs.yaml
+var initMenuData []byte
+
+// menuDefinitions gives the menu definitions.
+var menuDefinitions MenuDefs
+
+// init loads the menu definitions.
+func init() {
+	if err := yaml.Unmarshal(initMenuData, &menuDefinitions); err != nil {
+		panic(err) // can't happen
+	}
+	menuDefinitions.table = make(map[string]*MenuDefinition)
+	for i, d := range menuDefinitions.D {
+		menuDefinitions.table[d.ID] = &(menuDefinitions.D[i])
+		for j := range menuDefinitions.D[i].Items {
+			menuDefinitions.D[i].Items[j].P = &(menuDefinitions.D[i])
+		}
+	}
+}
+
+// AmMenu returns a menu definition.
+func AmMenu(name string) *MenuDefinition {
+	return menuDefinitions.table[name]
+}