ref: 1415efdcd838cf482072ef08e765a8ce960bfdde
dir: /navigation/menu.go/
// Copyright 2019 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package navigation
import (
"github.com/gohugoio/hugo/common/maps"
"github.com/gohugoio/hugo/common/types"
"github.com/gohugoio/hugo/compare"
"html/template"
"sort"
"strings"
"github.com/spf13/cast"
)
// MenuEntry represents a menu item defined in either Page front matter
// or in the site config.
type MenuEntry struct {
ConfiguredURL string // The URL value from front matter / config.
Page Page
Name string
Menu string
Identifier string
title string
Pre template.HTML
Post template.HTML
Weight int
Parent string
Children Menu
Params maps.Params
}
func (m *MenuEntry) URL() string {
if m.ConfiguredURL != "" {
return m.ConfiguredURL
}
if !types.IsNil(m.Page) {
return m.Page.RelPermalink()
}
return ""
}
// A narrow version of page.Page.
type Page interface {
LinkTitle() string
RelPermalink() string
Section() string
Weight() int
IsPage() bool
Params() maps.Params
}
// Menu is a collection of menu entries.
type Menu []*MenuEntry
// Menus is a dictionary of menus.
type Menus map[string]Menu
// PageMenus is a dictionary of menus defined in the Pages.
type PageMenus map[string]*MenuEntry
// HasChildren returns whether this menu item has any children.
func (m *MenuEntry) HasChildren() bool {
return m.Children != nil
}
// KeyName returns the key used to identify this menu entry.
func (m *MenuEntry) KeyName() string {
if m.Identifier != "" {
return m.Identifier
}
return m.Name
}
func (m *MenuEntry) hopefullyUniqueID() string {
if m.Identifier != "" {
return m.Identifier
} else if m.URL() != "" {
return m.URL()
} else {
return m.Name
}
}
// IsEqual returns whether the two menu entries represents the same menu entry.
func (m *MenuEntry) IsEqual(inme *MenuEntry) bool {
return m.hopefullyUniqueID() == inme.hopefullyUniqueID() && m.Parent == inme.Parent
}
// IsSameResource returns whether the two menu entries points to the same
// resource (URL).
func (m *MenuEntry) IsSameResource(inme *MenuEntry) bool {
murl, inmeurl := m.URL(), inme.URL()
return murl != "" && inmeurl != "" && murl == inmeurl
}
func (m *MenuEntry) MarshallMap(ime map[string]interface{}) {
for k, v := range ime {
loki := strings.ToLower(k)
switch loki {
case "url":
m.ConfiguredURL = cast.ToString(v)
case "weight":
m.Weight = cast.ToInt(v)
case "name":
m.Name = cast.ToString(v)
case "title":
m.title = cast.ToString(v)
case "pre":
m.Pre = template.HTML(cast.ToString(v))
case "post":
m.Post = template.HTML(cast.ToString(v))
case "identifier":
m.Identifier = cast.ToString(v)
case "parent":
m.Parent = cast.ToString(v)
case "params":
m.Params = maps.ToStringMap(v)
}
}
}
func (m Menu) Add(me *MenuEntry) Menu {
m = append(m, me)
// TODO(bep)
m.Sort()
return m
}
/*
* Implementation of a custom sorter for Menu
*/
// A type to implement the sort interface for Menu
type menuSorter struct {
menu Menu
by menuEntryBy
}
// Closure used in the Sort.Less method.
type menuEntryBy func(m1, m2 *MenuEntry) bool
func (by menuEntryBy) Sort(menu Menu) {
ms := &menuSorter{
menu: menu,
by: by, // The Sort method's receiver is the function (closure) that defines the sort order.
}
sort.Stable(ms)
}
var defaultMenuEntrySort = func(m1, m2 *MenuEntry) bool {
if m1.Weight == m2.Weight {
c := compare.Strings(m1.Name, m2.Name)
if c == 0 {
return m1.Identifier < m2.Identifier
}
return c < 0
}
if m2.Weight == 0 {
return true
}
if m1.Weight == 0 {
return false
}
return m1.Weight < m2.Weight
}
func (ms *menuSorter) Len() int { return len(ms.menu) }
func (ms *menuSorter) Swap(i, j int) { ms.menu[i], ms.menu[j] = ms.menu[j], ms.menu[i] }
// Less is part of sort.Interface. It is implemented by calling the "by" closure in the sorter.
func (ms *menuSorter) Less(i, j int) bool { return ms.by(ms.menu[i], ms.menu[j]) }
// Sort sorts the menu by weight, name and then by identifier.
func (m Menu) Sort() Menu {
menuEntryBy(defaultMenuEntrySort).Sort(m)
return m
}
// Limit limits the returned menu to n entries.
func (m Menu) Limit(n int) Menu {
if len(m) > n {
return m[0:n]
}
return m
}
// ByWeight sorts the menu by the weight defined in the menu configuration.
func (m Menu) ByWeight() Menu {
menuEntryBy(defaultMenuEntrySort).Sort(m)
return m
}
// ByName sorts the menu by the name defined in the menu configuration.
func (m Menu) ByName() Menu {
title := func(m1, m2 *MenuEntry) bool {
return compare.LessStrings(m1.Name, m2.Name)
}
menuEntryBy(title).Sort(m)
return m
}
// Reverse reverses the order of the menu entries.
func (m Menu) Reverse() Menu {
for i, j := 0, len(m)-1; i < j; i, j = i+1, j-1 {
m[i], m[j] = m[j], m[i]
}
return m
}
func (m *MenuEntry) Title() string {
if m.title != "" {
return m.title
}
if m.Page != nil {
return m.Page.LinkTitle()
}
return ""
}