Fediversity/website/presentation/default.nix
Valentin Gagarin 5ee1c8b006 implement sectioning semantics
this was quite a beast to tame, but it now allows putting sections anywhere
in the tree without having to redundantly specify heading levels, which
will be computed automatically from the nesting depth.

the whole thing will also blow up if the maximum section nesting depth
is exceeded, just as the spec requires - albeit with an absolutely
impenetrable error message. this could in principle be improved with
lots of additional machinery, but this is by far not low-hanging fruit.

just don't nest your sections too much.
2024-11-13 15:47:12 +01:00

128 lines
4 KiB
Nix

{ config, options, lib, pkgs, ... }:
let
inherit (lib)
mkOption
types
;
templates = import ./templates.nix { inherit lib; };
# TODO: optionally run the whole thing through the validator
# https://github.com/validator/validator
render-html = document:
let
eval = lib.evalModules {
class = "DOM";
modules = [ document (import ./dom.nix) ];
};
in
toString eval.config;
in
{
options.templates =
let
# arbitrarily nested attribute set where the leaves are of type `type`
# NOTE: due to how `either` works, the first match is significant,
# so if `type` happens to be an attrset, the typecheck will consider
# `type`, not `attrsOf`
recursiveAttrs = type: with types; attrsOf (either type (recursiveAttrs type));
in
mkOption {
description = ''
Collection of named functions to convert document contents to a string representation
Each template function takes the complete site `config` and the document's data structure.
'';
# TODO: this function should probably take a single attrs,
# otherwise it's quite inflexible.
# named parameters would also help with readability at the call site
type = recursiveAttrs (with types; functionTo (functionTo str));
};
config.templates.html =
let
commonmark = name: markdown: pkgs.runCommand "${name}.html"
{
buildInputs = [ pkgs.cmark ];
} ''
cmark ${builtins.toFile "${name}.md" markdown} > $out
'';
in
{
nav = lib.mkDefault templates.nav;
page = lib.mkDefault (config: page: render-html {
html = {
head = {
title.text = page.title;
meta.description = page.description;
link.canonical = lib.head page.locations;
};
body.content = [
(config.menus.main.outputs.html page)
{ section.heading.content = page.title; }
(builtins.readFile (commonmark page.name page.body))
];
};
});
article = lib.mkDefault (config: page: render-html {
html = {
head = {
title.text = page.title;
meta.description = page.description;
meta.authors = if lib.isList page.author then page.author else [ page.author ];
link.canonical = lib.head page.locations;
};
body.content = [
(config.menus.main.outputs.html page)
{ section.heading.content = page.title; }
(builtins.readFile (commonmark page.name page.body))
];
};
});
};
options.files = mkOption {
description = ''
Files that make up the site, mapping from output path to contents
By default, all elements in `option`{pages} are converted to files using their template or the default template.
Add more files to the output by assigning to this attribute set.
'';
type = with types; attrsOf path;
};
config.files =
# TODO: create static redirects from `tail page.locations`
let
pages = lib.attrValues config.pages;
collections = with lib; concatMap (collection: collection.entry) (attrValues config.collections);
in
with lib; foldl
(acc: elem: acc // {
# TODO: we may or may not want to enforce the mapping of file types to output file name suffixes
"${head elem.locations}.html" = builtins.toFile "${elem.name}.html" elem.outputs.html;
})
{ }
(pages ++ collections);
options.build = mkOption {
description = ''
The final output of the web site
'';
type = types.package;
default =
let
script = ''
mkdir $out
'' + lib.join "\n" copy;
copy = lib.mapAttrsToList
(
path: file: ''
mkdir -p $out/$(dirname ${path})
cp -r ${file} $out/${path}
''
)
config.files;
in
pkgs.runCommand "source" { } script;
};
}