============
A language is chosen as the "master" one, and any other supported
-language is a "slave" one. A page written in the "master" language is
-a "master" page, and is written in any supported format but PO.
+language is a "slave" one.
+
+A page written in the "master" language is a "master" page, and is
+written in any supported format but PO. It does not have to be named
+a special way: migration from/to this plugin does not imply heavy
+renaming work.
Example: `bla/page.mdwn` is a "master" Markdown page written in
English; if `usedirs` is enabled, it is rendered as
'de' => { 'name' => 'Deutsch', }
}
+Decide which pages are translatable
+-----------------------------------
+
+The `po_translatable_pages` setting configures what pages are
+translatable. It is a [[ikiwiki/PageSpec]], so you have lots of
+control over what kind of pages are translatable.
+
+The `*.LL.po` translations files are anyway not considered as being
+translatable, so you don't need to worry about excluding them manually
+from this [[ikiwiki/PageSpec]].
+
+Internal links
+--------------
+
+One can use the `po_link_to_` option in `ikiwiki.setup` to choose how
+internal links should be generated, depending on web server features
+and site-specific preferences.
+
+### Default linking behavior
+
+If `po_link_to` is unset, or set to `default`, ikiwiki's default
+linking behavior is preserved: `[[page]]` links to the master
+language's page.
+
+### Link to negotiated language
+
+If `po_link_to` is set to `negotiated`, `[[page]]` links to the
+negotiated preferred language, *i.e.* `foo/page/`.
+
+(In)compatibility notes:
+
+- `po_link_to => negotiated` provides no useful behavior if `usedirs`
+ is disabled; this option combination is neither implemented nor
+ allowed
+- `po_link_to => negotiated` provides no useful behavior if the web
+ server does not support Content Negotiation
+
+### Link to current language
+
+If `po_link_to` is set to `current` and the destination page is either
+a translatable page or a translation, `[[page]]` links to the current
+page's language, *i.e.*:
+
+- `foo/page/index.LL.html` if `usedirs` is enabled
+- `foo/page.LL.html` if `usedirs` is disabled
+
Server support
==============
TODO
====
-Links
------
-
-Choice between two behaviors must be possible in `ikiwiki.setup`;
-a `po_link_to_current_language` option must allow switching
-between them.
-
-If `po_link_to_current_language` is disabled, `[[page]]` links to the
-negotiated preferred language, i.e.:
+Optimization
+------------
-- `usedirs` enabled: `bla/page/`
-- `usedirs` disabled: `bla/page`
+Pre-compute what can be early in the build process:
-This obviously does not work in case Content Negotiation is not
-supported by the web server, hence one can enable
-`po_link_to_current_language` to make `[[page]]` link to the current
-page's language, i.e.:
+- the list of translatable (master) pages
+- for every translatable page, the list of slave pages
-- `usedirs` enabled: `bla/page/index.LL.html`
-- `usedirs` disabled: `bla/page.LL.html`
-
-**FIXME**: should `po_link_to_current_language` be enabled by default?
+... and/or memoize `istranslation`/`istranslatable` function calls.
Display available translations
------------------------------
loop, a page using it should depend on any "master" and "slave" pages
whose status is being displayed.
-Decide which pages are translatable
------------------------------------
-
-The subset of "master" pages subject to translation must be
-configurable:
-
-- a `[[!translatable ]]` directive, when put on a page, makes it
- translatable
-- to set at once a bunch of pages as being translatable, use this
- [[ikiwiki/directive]] with the `match=PageSpec` argument.
-
Automatic PO files update
-------------------------