html.nix/pkgs-lib.nix

{
  utils,
  pkgs,
}: let
  pkgBin = name: "${pkgs.${name}}/bin/${name}";

  mkServePathScript = path:
    pkgs.writeScriptBin "serve" ''
      ${pkgs.nodePackages.http-server}/bin/http-server -c-1 ${path}
    '';

  mkSitePath = site: let
    inherit (utils) recursiveAttrPaths concatStringsSep map;
    inherit (pkgs.lib) mapAttrsRecursive init last getAttrFromPath;

    convertToPath = path: value:
      if builtins.isPath value
      then value
      else pkgs.writeText (concatStringsSep "-" path) value;
    fileAttrPaths = recursiveAttrPaths site;
    texts = mapAttrsRecursive convertToPath site;
    mkCreateFileCmd = path: value: let p = concatStringsSep "/" (init path); in "mkdir -p \"$out/${p}\" && ln -s \"${value}\" \"$out/${p}/${last path}\"";
    createFileCmds = map (path: mkCreateFileCmd path (getAttrFromPath path texts)) fileAttrPaths;
  in
    pkgs.runCommandLocal "site-path" {} ''
      mkdir -p $out
      ${concatStringsSep "\n" createFileCmds}
    '';

  parseMarkdown = name: contents:
    pkgs.runCommandLocal name {} ''
      printf ${pkgs.lib.escapeShellArg contents} | ${pkgBin "pandoc"} -f gfm > $out
    '';
in {
  inherit mkServePathScript mkSitePath parseMarkdown;

  mkServeFromSite = site: mkServePathScript (mkSitePath site);
  mkSiteFrom = {
    src,
    templater,
    local ? false,
  }: let
    inherit (utils) readDir readFile fromTOML mapAttrsToList sort elemAt;
    inherit (pkgs.lib) nameValuePair head splitString pipe removeSuffix mapAttrs';

    postsRendered = let
      path = src + "/posts";
    in
      pipe (readDir path) [
        (mapAttrsToList (
          name: _:
            nameValuePair
            (head (splitString "." name))
            (readFile (parseMarkdown name (readFile (path + "/${name}"))))
        ))
        (sort (
          p: op: let
            extractDate = name: splitString "-" (head (splitString "_" name));
            getPart = name: el: removeSuffix "0" (elemAt (extractDate name) el);
            d = getPart p.name;
            od = getPart op.name;
          in
            !(((d 0) > (od 0)) && ((d 1) > (od 1)) && ((d 2) > (od 2)))
        ))
      ];
    pagesRendered = let
      path = src + "/pages";
    in
      mapAttrs'
      (
        name: _:
          nameValuePair
          (head (splitString "." name))
          (readFile (parseMarkdown name (readFile (path + "/${name}"))))
      )
      (readDir path);
    siteConfig = fromTOML (readFile (src + "/config.toml"));
    baseurl =
      if local
      then "http://localhost:8080"
      else siteConfig.baseurl or (throw "Need baseurl");

    context = {
      inherit utils pkgs baseurl;
      config = siteConfig;
      posts = postsRendered;
      pages = pagesRendered;
      site = {
        "robots.txt" = ''
          User-agent: *
          Allow: /
        '';
      };
    };
  in
    (templater context).site;
}