====== color Plugin ======

---- plugin ----
description: Opportunity to write colored text in DokuWiki
author     : Harald Hanche-Olsen
email      : harald.hanche-olsen@ntnu.no
type       : Syntax
lastupdate : 2022-10-19
compatible : Adora Belle, Weatherwax, Binky, Ponder Stibbons, Detritus, Elenor Of Tsort, Frusterick Manners, Greebo, Hogfather, Igor, Jack Jackrum, Kaos
depends    : 
conflicts  : 
similar    : fontcolor, emphasis, wrap
tags       : typography, highlight, color, text

downloadurl: https://github.com/hanche/dokuwiki_color_plugin/archive/refs/tags/2022-10-19.tar.gz
sourcerepo : https://github.com/hanche/dokuwiki_color_plugin
bugtracker : https://github.com/hanche/dokuwiki_color_plugin/issues

screenshot_img: https://folk.ntnu.no/hanche/tmp/dokuwiki_color_plugin.png
----

===== Installation =====

Please use the [[plugin:extension|extension manager]] to install the plugin, no configuration needed.

===== Usage =====

Place this code sample in your playground:

<code>
<color green>text</color>
<color blue/lightgrey>text</color>
<color #FF0000>text</color>
<color /#FFff00>text</color>
<color rgb(80%,0%,0%)/rgb(100%,80%,100%)>text</color>
<color hsl(120,100%,30%):hsl(180,50%,90%)>text</color>
</code>

and you will see something like this:

{{https://folk.ntnu.no/hanche/tmp/dokuwiki_color_plugin.png|Color plugin in action}}

The foreground or background color specification can be any valid CSS color specification. Beware that some older browsers will not recognise all color specs in the latest CSS version.

If you use a color specification that contains a slash (''/''), you must use a colon ('':'') to separate the foreground and background color specs.

The precise syntax is as follows. Square brackets (''[]'') indicate optional parts, and should //not// be included literally:
<code>
<color [⟨fg-color⟩][/⟨bg-color⟩]>⟨text⟩</color>
<color [⟨fg-color⟩]:[⟨bg-color⟩]>⟨text⟩</color>
</code>
You //must// use the second form if either color spec includes a slash.
Note that in that case, the colon separater ('':'') is mandatory.

No valid color spec including a colon is known at this time, but if you need to use one in the future, you //must// use the first form. This plugin does not provide a way to combine these.

The result is ⟨text⟩ shown with foreground color ⟨fg-color⟩ and background color ⟨bg-color⟩. If either color is omitted or empty, the foreground or background color of the surrounding text is used.

Example – note the mandatory colon here:

<code>
<color hwb(120 20% 30% / 50%):>some faded dark green semi-transparent text</color>
</code>

Harmless restriction:
This plugin now allows any color specification not containing single or double quotes or any of the symbols ''%%< > & ; %%''. It does not try to check if the specification is valid CSS. This is to accommodate the CSS 4 color specifications, as well as any future color specifications – so long as they do not use any of the “forbidden” characters.

For a reference of usable color specifications, see
[[https://developer.mozilla.org/en-US/docs/Web/CSS/color_value|the color page]] at developer.mozilla.org.
Beware that not all color specifications work on all browsers.
See the bottom of the referenced page for more information, or
check [[https://caniuse.com/|Can I Use]] if in doubt.

  * The plugin works by wrapping contents in a %%<span>%% element with a suitable %%style%% attribute. Therefore, you cannot wrap it around block level items such as headers, lists, and tables.
  * You cannot use it //inside// headers either, since [[faq:headerlinks|you can't use wiki syntax]] within a header.
  * The use of two or more separators (slashes in the first syntax, colons in the second) within %%''<color …>''%% results in undefined behaviour. 

===== Discussion =====

This source for this plugin is shown in the [[devel:Syntax Plugins#sample_plugin_2_-_color|Sample Plugin Tutorial]].

===== Development =====

**Christopher Smith** seems to have left the plugin unmaintained. User **leeyc0** provided hosting of the plugin on github, but has no time to maintain it either. **Harald Hanche-Olsen** took over in October 2018. The plugin is considered fairly stable, though, and the new maintainer does not foresee a very active maintenance schedule. New feature requests will likely be rejected.

===== Update History =====

  * 2022-10-19 Allow the use of a colon separator, so that the color specs may contain a slash
  * 2022-10-16 Removed the (too stringent) syntax checking of the color specifications, in order to be able to handle CSS 4 colors and possible future color specs
  * 2022-09-15 Removed deprecated and unnecessary (but harmless) code
  * 2018-10-12 New maintainer
  * 2018-10-10 Added support for rgb[a](…) and hsl[a](…) color specifications
  * 2018-08-09 Added code for handling metadata to the render method
  * 2016-06-25 Added ODT support based on branch "redesign"
  * 2014-01-04 hosted in github by leeyc0
  * 2008-02-06 --- Fixed a security vulnerability in the colour pattern. Any users of this plugin should apply this update.  --- //[[chris@jalakai.co.uk|Christopher Smith]] 2008-02-06 17:20//