====== WvdS.DokuWiki.If Plugin ======

**Plugin:** wvdsif\\
**Version:** 1.0.0\\
**Namespace:** ''lib/plugins/wvdsif/''\\
**Author:** Wolfgang van der Stille <zeljko.petrusic@outlook.de>\\
**License:** GPL 2

----

===== Definition =====

The **wvdsif** plugin enables conditional content display based on user groups or browser language. It provides two tag types: ''<ifgroup>'' for group-based display and ''<iflang>'' for language-based display.

===== Use Cases =====

  * **Permission-based Content** - Different content for guests, users, admins
  * **Multilingual Landing Pages** - Language-specific greetings and content
  * **Admin Sections** - Hidden links visible only to administrators
  * **Fallback Content** - Default content when no language matches
  * **VIP Areas** - Exclusive content for specific groups

----

===== Syntax =====

==== ifgroup - By User Group ====

<code>
<ifgroup groupname>Content for this group</ifgroup>
<ifgroup group1,group2>Content for multiple groups</ifgroup>
</code>

==== iflang - By Browser Language ====

<code>
<iflang languagecode>Content for this language</iflang>
<iflang code1,code2>Content for multiple languages</iflang>
<iflang *>Fallback content (always displayed)</iflang>
</code>

----

===== Parameters =====

==== ifgroup Parameters ====

^ Parameter ^ Type ^ Description ^
| ''guest'' | predefined | Not logged-in visitors |
| ''user'' | predefined | All logged-in users |
| ''admin'' | predefined | Administrators |
| ''[groupname]'' | custom | Any group defined in DokuWiki |

==== iflang Parameters ====

^ Parameter ^ Type ^ Description ^
| ''de'' | ISO 639-1 | German |
| ''en'' | ISO 639-1 | English |
| ''sl'' | ISO 639-1 | Slovenian |
| ''fr'' | ISO 639-1 | French |
| ''es'' | ISO 639-1 | Spanish |
| ''it'' | ISO 639-1 | Italian |
| ''*'' | Wildcard | All languages (fallback) |

----

===== Examples =====

==== Example 1: Guests vs. Logged-in ====

**Requirement:** Different greeting for guests and logged-in users.

<code>
<ifgroup guest>
===== Welcome! =====
Please [[?do=login|log in]] for full access.
</ifgroup>

<ifgroup user>
===== Welcome Back! =====
You have access to all documentation.
</ifgroup>
</code>

**Result:**
  * Not logged in: Shows login prompt
  * Logged in: Shows welcome message

==== Example 2: Admin Section ====

**Requirement:** Admin links visible only to administrators.

<code>
<ifgroup admin>
===== Administration =====
  * [[admin:dashboard|Dashboard]]
  * [[admin:users|Manage Users]]
  * [[admin:plugins|Manage Plugins]]
  * [[admin:config|Configuration]]
</ifgroup>
</code>

**Result:**
  * Admin: Sees all admin links
  * Other users: Block is invisible

==== Example 3: Multilingual Landing Page ====

**Requirement:** Greeting in the visitor's browser language.

<code>
<iflang de>
===== Willkommen =====
Dies ist unsere Wissensdatenbank auf Deutsch.
</iflang>

<iflang en>
===== Welcome =====
This is our knowledge base in English.
</iflang>

<iflang sl>
===== Dobrodošli =====
To je naša baza znanja v slovenščini.
</iflang>

<iflang *>
===== Welcome =====
Please select your language above.
</iflang>
</code>

**Result:**
  * Browser set to German: Shows German block
  * Browser set to English: Shows English block
  * Browser set to Slovenian: Shows Slovenian block
  * Other languages: Shows fallback block

==== Example 4: Multilingual Error Page ====

**Requirement:** 404 page in the visitor's language.

<code>
<iflang de>
===== Seite nicht gefunden =====
Die angeforderte Seite existiert nicht.
[[start|Zurück zur Startseite]]
</iflang>

<iflang en>
===== Page Not Found =====
The requested page does not exist.
[[start|Back to homepage]]
</iflang>

<iflang *>
===== Error 404 =====
Page not found.
[[start|Home]]
</iflang>
</code>

==== Example 5: VIP Content ====

**Requirement:** Premium content only for VIP members.

<code>
<ifgroup vip,premium>
===== Exclusive Area =====
Here you'll find premium documentation and advanced tutorials.
  * [[premium:advanced|Advanced Features]]
  * [[premium:tutorials|Exclusive Tutorials]]
</ifgroup>

<ifgroup guest,user>
===== Premium Area =====
This area is reserved for VIP members.
[[contact|Request Upgrade]]
</ifgroup>
</code>

==== Example 6: Combined Conditions ====

**Requirement:** Multiple groups in a sidebar.

<code>
~~NOCACHE~~
===== Navigation =====
  * [[start|Home]]
  * [[docs:index|Documentation]]

<ifgroup user,admin>
  * [[internal:index|Internal Area]]
</ifgroup>

<ifgroup admin>
  * [[admin:index|Administration]]
</ifgroup>

<ifgroup guest>
  * [[?do=login|Log In]]
</ifgroup>
</code>

----

===== How It Works =====

==== Processing Pipeline ====

<code>
1. Tag Detection
   └── Finds all <ifgroup>...</ifgroup> and <iflang>...</iflang> tags

2. Condition Check
   ├── ifgroup: Checks $_SERVER['REMOTE_USER'] and group membership
   └── iflang: Checks Accept-Language header

3. Content Filtering
   ├── Condition met: Content is displayed
   └── Condition not met: Content is removed

4. Wildcard Processing
   └── <iflang *> is checked last (only if no other language matches)
</code>

==== Language Detection ====

The language is detected from the ''Accept-Language'' HTTP header:

<code>
Accept-Language: de-DE,de;q=0.9,en;q=0.8
                 ^^
                 Primary language: "de"
</code>

^ Header Example ^ Detected Language ^
| ''de-DE,de;q=0.9'' | de |
| ''en-US,en;q=0.9'' | en |
| ''sl-SI,sl;q=0.9'' | sl |
| ''fr-FR,en;q=0.5'' | fr |

----

===== Configuration =====

The plugin requires no special configuration. Group detection uses standard DokuWiki ACL groups.

==== Important Note ====

<note important>
Pages with ''<ifgroup>'' or ''<iflang>'' tags should use ''~~NOCACHE~~'' so content is re-rendered on each request.
</note>

----

===== Error Handling =====

^ Scenario ^ Behavior ^
| Unknown group | Block is not displayed |
| Invalid language code | Block is not displayed |
| No Accept-Language header | Only ''*'' wildcard is displayed |
| Nested tags | Outer tag takes priority |

----

===== Best Practices =====

  * **~~NOCACHE~~** always use when ifgroup/iflang is used
  * **Fallback with *** provide for iflang
  * **Define groups clearly** in DokuWiki ACL
  * **Don't nest** - tags should not be nested inside each other

==== Correct ====

<code>
<ifgroup admin>Admin content</ifgroup>
<ifgroup user>User content</ifgroup>
</code>

==== Incorrect ====

<code>
<ifgroup admin>
  <ifgroup user>Nested content</ifgroup>
</ifgroup>
</code>

----

===== Version History =====

^ Version ^ Date ^ Changes ^
| 1.0.0 | 2025-01-06 | Initial release |

----

===== See Also =====

  * [[wvdslang]] - Multilingual translations
  * [[wvdschunk]] - Reusable HTML components
  * [[flat]] - Template with language switcher

----

===== Technical Reference =====

==== Class: syntax_plugin_wvdsif ====

**File:** ''lib/plugins/wvdsif/syntax.php''

^ Method ^ Description ^
| ''getType()'' | Returns ''substition'' |
| ''getSort()'' | Returns ''100'' |
| ''connectTo($mode)'' | Registers ifgroup and iflang patterns |
| ''handle($match, ...)'' | Parses tag and extracts condition |
| ''render($mode, ...)'' | Returns content or empty |

==== Helper Functions ====

^ Function ^ Description ^
| ''_checkGroup($groups)'' | Checks group membership |
| ''_checkLang($langs)'' | Checks language match |
| ''_getBrowserLang()'' | Extracts language from Accept-Language |

==== Variables Used ====

^ Variable ^ Source ^ Description ^
| ''$_SERVER['REMOTE_USER']'' | PHP | Logged-in username |
| ''$USERINFO['grps']'' | DokuWiki | User groups array |
| ''$_SERVER['HTTP_ACCEPT_LANGUAGE']'' | HTTP | Browser language setting |

----

{{wvds:snippet>wvds_audit_badge}}

~~DISCUSSION~~