Doc: sync from Wiki, generate HTML

Closes #291
Fixes #227

Modifications
 - HTML content: match the new Wiki structure
 - Makefile
   - generate a custom HTML sidebar
   - include the sidebar on all pages
   - infer and prepend page titles
   - handle relative links
   - add title metadata, e.g. Shaarli - <Page Name>

Signed-off-by: VirtualTam <virtualtam@flibidi.net>

1 files changed, 590 insertions, 0 deletions

diff --git a/doc/Plugin-System.md b/doc/Plugin-System.md
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+#Plugin System
+> Note: Plugin current status - in developpement (not merged into master).
+
+[**I am a user.** Plugin User Guide.](#plugin-user-guide)[](.html)
+
+[**I am a developper.** Developper API.](#developper-api)[](.html)
+
+[**I am a template designer.** Guide for template designer.](#guide-for-template-designer)[](.html)
+
+## Plugin User Guide
+
+### Manage plugins
+
+In `config.php`, change $GLOBALS['config'['ENABLED_PLUGINS'] array:]('ENABLED_PLUGINS']-array:.html)
+
+```php
+$GLOBALS['config'['ENABLED_PLUGINS']]('ENABLED_PLUGINS'].html)
+```
+
+Full list:
+
+```php
+$GLOBALS['config'['ENABLED_PLUGINS'] = array(]('ENABLED_PLUGINS']-=-array(.html)
+    'qrcode', 'archiveorg', 'readityourself', 'playvideos',
+    'wallabag', 'markdown', 'addlink_toolbar',
+);
+```
+
+### List of plugins
+
+Plugin maintained by the community:
+
+  * Archive.org - add a clickable icon to every link to archive.org.
+  * Addlink in toolbar - add a field to paste new links URL in toolbar.
+  * Markdown - write and display Shaare in Markdown.
+  * Play videos - popup to play all videos displayed in linklist.
+  * QRCode - add a clickable icon generating a QRCode for every link.
+  * ReadItYourself - add a clickable icon for ReadItYourself.
+  * Wallabag - add a clickable icon for Wallabag.
+
+## Developper API
+
+### What can I do with plugins?
+
+The plugin system let you:
+
+  * insert content into specific places across templates.
+  * alter data before templates rendering.
+  * alter data before saving new links.
+
+### How can I create a plugin for Shaarli?
+
+First, chose a plugin name, such as `demo_plugin`.
+
+Under `plugin` folder, create a folder named with your plugin name. Then create a <plugin_name>.php file in that folder.
+
+You should have the following tree view:
+
+```
+| index.php
+| plugins/
+|---| demo_plugin/
+|   |---| demo_plugin.php
+```
+
+### Understanding hooks
+
+A plugin is a set of functions. Each function will be triggered by the plugin system at certain point in Shaarli execution.
+
+These functions need to be named with this pattern:
+
+```
+hook_<plugin_name>_<hook_name>
+```
+
+For exemple, if my plugin want to add data to the header, this function is needed:
+
+    hook_demo_plugin_render_header()
+
+If this function is declared, and the plugin enabled, it will be called every time Shaarli is rendering the header.
+
+### Plugin's data
+
+#### Parameters
+
+Every hook function has a `$data` parameter. Its content differs for each hooks.
+
+**This parameter needs to be returned every time**, otherwise data is lost.
+
+    return $data;
+
+#### Filling templates placeholder
+
+Template placeholders are displayed in template in specific places.
+
+RainTPL displays every element contained in the placeholder's array. These element can be added by plugins.
+
+For example, let's add a value in the placeholder `top_placeholder` which is displayed at the top of my page:
+
+```php
+$data['top_placeholder'[] = 'My content';](]-=-'My-content';.html)
+# OR
+array_push($data['top_placeholder'], 'My', 'content');[](.html)
+
+return $data;
+```
+
+#### Data manipulation
+
+When a page is displayed, every variable send to the template engine is passed to plugins before that in `$data`.
+
+The data contained by this array can be altered before template rendering.
+
+For exemple, in linklist, it is possible to alter every title:
+
+```php
+// mind the reference if you want $data to be altered
+foreach ($data['links'] as &$value) {[](.html)
+    // String reverse every title.
+    $value['title'] = strrev($value['title']);[](.html)
+}
+
+return $data;
+```
+
+### It's not working!
+
+Use `demo_plugin` as a functional example. It covers most of the plugin system features.
+
+If it's still not working, please [open an issue](https://github.com/shaarli/Shaarli/issues/new).[](.html)
+
+### Hooks
+
+| Hooks         | Description   |
+| ------------- |:-------------:|
+| [render_header](#render_header) | Allow plugin to add content in page headers. |[](.html)
+| [render_includes](#render_includes) | Allow plugin to include their own CSS files. |[](.html)
+| [render_footer](#render_footer) | Allow plugin to add content in page footer and include their own JS files. | [](.html)
+| [render_linklist](#render_linklist) | It allows to add content at the begining and end of the page, after every link displayed and to alter link data. |[](.html)
+| [render_editlink](#render_editlink) |  Allow to add fields in the form, or display elements. |[](.html)
+| [render_tools](#render_tools) |  Allow to add content at the end of the page. |[](.html)
+| [render_picwall](#render_picwall) |  Allow to add content at the top and bottom of the page. |[](.html)
+| [render_tagcloud](#render_tagcloud) |  Allow to add content at the top and bottom of the page. |[](.html)
+| [render_daily](#render_daily) |  Allow to add content at the top and bottom of the page, the bottom of each link and to alter data. |[](.html)
+| [savelink](#savelink) | Allow to alter the link being saved in the datastore. |[](.html)
+
+
+#### render_header
+
+Triggered on every page.
+
+Allow plugin to add content in page headers.
+
+##### Data
+
+`$data` is an array containing:
+
+  * `_PAGE_`: current target page (eg: `linklist`, `picwall`, etc.).
+  * `_LOGGEDIN_`: true if user is logged in, false otherwise.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `buttons_toolbar`: after the list of buttons in the header.
+
+![buttons_toolbar_example](http://i.imgur.com/ssJUOrt.png)[](.html)
+
+  * `fields_toolbar`: after search fields in the header.
+
+> Note: This will only be called in linklist.
+
+![fields_toolbar_example](http://i.imgur.com/3GMifI2.png)[](.html)
+
+#### render_includes
+
+Triggered on every page.
+
+Allow plugin to include their own CSS files.
+
+##### Data
+
+`$data` is an array containing:
+
+  * `_PAGE_`: current target page (eg: `linklist`, `picwall`, etc.).
+  * `_LOGGEDIN_`: true if user is logged in, false otherwise.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `css_files`: called after loading default CSS.
+
+> Note: only add the path of the CSS file. E.g: `plugins/demo_plugin/custom_demo.css`.
+
+#### render_footer
+
+Triggered on every page.
+
+Allow plugin to add content in page footer and include their own JS files.
+
+##### Data
+
+`$data` is an array containing:
+
+  * `_PAGE_`: current target page (eg: `linklist`, `picwall`, etc.).
+  * `_LOGGEDIN_`: true if user is logged in, false otherwise.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `text`: called after the end of the footer text.
+
+![text_example](http://i.imgur.com/L5S2YEH.png)[](.html)
+
+  * `js_files`: called at the end of the page, to include custom JS scripts.
+
+> Note: only add the path of the JS file. E.g: `plugins/demo_plugin/custom_demo.js`.
+
+#### render_linklist
+
+Triggered when `linklist` is displayed (list of links, permalink, search, tag filtered, etc.).
+
+It allows to add content at the begining and end of the page, after every link displayed and to alter link data.
+
+##### Data
+
+`$data` is an array containing:
+
+  * `_LOGGEDIN_`: true if user is logged in, false otherwise.
+  * All templates data, including links.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `action_plugin`: next to the button "private only" at the top and bottom of the page.
+
+![action_plugin_example](http://i.imgur.com/Q12PWg0.png)[](.html)
+
+  * `link_plugin`: for every link, between permalink and link URL.
+
+![link_plugin_example](http://i.imgur.com/3oDPhWx.png)[](.html)
+
+  * `plugin_start_zone`: before displaying the template content.
+
+![plugin_start_zone_example](http://i.imgur.com/OVBkGy3.png)[](.html)
+
+  * `plugin_end_zone`: after displaying the template content.
+
+![plugin_end_zone_example](http://i.imgur.com/6IoRuop.png)[](.html)
+
+#### render_editlink
+
+Triggered when the link edition form is displayed.
+
+Allow to add fields in the form, or display elements.
+
+##### Data
+
+`$data` is an array containing:
+
+  * All templates data.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `edit_link_plugin`: after tags field.
+
+![edit_link_plugin_example](http://i.imgur.com/5u17Ens.png)[](.html)
+
+#### render_tools
+
+Triggered when the "tools" page is displayed.
+
+Allow to add content at the end of the page.
+
+##### Data
+
+`$data` is an array containing:
+
+  * All templates data.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `tools_plugin`: at the end of the page.
+
+![tools_plugin_example](http://i.imgur.com/Bqhu9oQ.png)[](.html)
+
+#### render_picwall
+
+Triggered when picwall is displayed.
+
+Allow to add content at the top and bottom of the page.
+
+##### Data
+
+`$data` is an array containing:
+
+  * `_LOGGEDIN_`: true if user is logged in, false otherwise.
+  * All templates data.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `plugin_start_zone`: before displaying the template content.
+
+  * `plugin_end_zone`: after displaying the template content.
+
+![plugin_start_end_zone_example](http://i.imgur.com/tVTQFER.png)[](.html)
+
+#### render_tagcloud
+
+Triggered when tagcloud is displayed.
+
+Allow to add content at the top and bottom of the page.
+
+##### Data
+
+`$data` is an array containing:
+
+  * `_LOGGEDIN_`: true if user is logged in, false otherwise.
+  * All templates data.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `plugin_start_zone`: before displaying the template content.
+
+  * `plugin_end_zone`: after displaying the template content.
+
+![plugin_start_end_zone_example](http://i.imgur.com/vHmyT3a.png)[](.html)
+
+#### render_daily
+
+Triggered when tagcloud is displayed.
+
+Allow to add content at the top and bottom of the page, the bottom of each link and to alter data.
+
+##### Data
+
+`$data` is an array containing:
+
+  * `_LOGGEDIN_`: true if user is logged in, false otherwise.
+  * All templates data, including links.
+
+##### Template placeholders
+
+Items can be displayed in templates by adding an entry in `$data['<placeholder>']` array.[](.html)
+
+List of placeholders:
+
+  * `link_plugin`: used at bottom of each link.
+
+![link_plugin_example](http://i.imgur.com/hzhMfSZ.png)[](.html)
+
+  * `plugin_start_zone`: before displaying the template content.
+
+  * `plugin_end_zone`: after displaying the template content.
+
+#### savelink
+
+Triggered when a link is save (new link or edit).
+
+Allow to alter the link being saved in the datastore.
+
+##### Data
+
+`$data` is an array containing the link being saved:
+
+  * title
+  * url
+  * description
+  * linkdate
+  * private
+  * tags
+
+## Guide for template designer
+
+### Placeholder system
+
+In order to make plugins work with every custom themes, you need to add variable placeholder in your templates. 
+
+It's a RainTPL loop like this:
+
+    {loop="$plugin_variable"}
+        {$value}
+    {/loop}
+
+You should enable `demo_plugin` for testing purpose, since it uses every placeholder available.
+
+### List of placeholders
+
+**page.header.html**
+
+At the end of the menu:
+
+    {loop="$plugins_header.buttons_toolbar"}
+        {$value}
+    {/loop}
+
+**includes.html**
+
+At the end of the file:
+
+```html
+{loop="$plugins_includes.css_files"}
+<link type="text/css" rel="stylesheet" href="{$value}#"/>
+{/loop}
+```
+
+**page.footer.html**
+
+At the end of your footer notes:
+
+```html
+{loop="$plugins_footer.text"}
+     {$value}
+{/loop}
+```
+
+At the end of file:
+
+```html
+{loop="$plugins_footer.js_files"}
+     <script src="{$value}#"></script>
+{/loop}
+```
+
+**linklist.html**
+
+After search fields:
+
+```html
+{loop="$plugins_header.fields_toolbar"}
+     {$value}
+{/loop}
+```
+
+Before displaying the link list (after paging):
+
+```html
+{loop="$plugin_start_zone"}
+     {$value}
+{/loop}
+```
+
+For every links (icons):
+
+```html
+{loop="$value.link_plugin"}
+    <span>{$value}</span>
+{/loop}
+```
+
+Before end paging:
+
+```html
+{loop="$plugin_end_zone"}
+     {$value}
+{/loop}
+```
+
+**linklist.paging.html**
+
+After the "private only" icon:
+
+```html
+{loop="$action_plugin"}
+     {$value}
+{/loop}
+```
+
+**editlink.html**
+
+After tags field:
+
+```html
+{loop="$edit_link_plugin"}
+     {$value}
+{/loop}
+```
+
+**tools.html**
+
+After the last tool:
+
+```html
+{loop="$tools_plugin"}
+     {$value}
+{/loop}
+```
+
+**picwall.html**
+
+Top:
+
+```html
+<div id="plugin_zone_start_picwall" class="plugin_zone">
+    {loop="$plugin_start_zone"}
+        {$value}
+    {/loop}
+</div>
+```
+
+Bottom:
+
+```html
+<div id="plugin_zone_end_picwall" class="plugin_zone">
+    {loop="$plugin_end_zone"}
+        {$value}
+    {/loop}
+</div>
+```
+
+**tagcloud.html**
+
+Top:
+
+```html
+   <div id="plugin_zone_start_tagcloud" class="plugin_zone">
+        {loop="$plugin_start_zone"}
+            {$value}
+        {/loop}
+    </div>
+```
+
+Bottom:
+
+```html
+    <div id="plugin_zone_end_tagcloud" class="plugin_zone">
+        {loop="$plugin_end_zone"}
+            {$value}
+        {/loop}
+    </div>
+```
+
+**daily.html**
+
+Top:
+
+```html
+<div id="plugin_zone_start_picwall" class="plugin_zone">
+     {loop="$plugin_start_zone"}
+         {$value}
+     {/loop}
+</div>
+```
+
+After every link:
+
+```html
+<div class="dailyEntryFooter">
+     {loop="$link.link_plugin"}
+          {$value}
+     {/loop}
+</div>
+```
+
+Bottom:
+
+```html
+<div id="plugin_zone_end_picwall" class="plugin_zone">
+    {loop="$plugin_end_zone"}
+        {$value}
+    {/loop}
+</div>
+```