chore(tvix): Add doc build infrastructure

Change-Id: I2cf67df085d0c008b5ff5efff2235a670207024a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2711
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
Reviewed-by: tazjin <mail@tazj.in>

third_party/nixpkgs-exposed/exposed/default.nix

@@ -106,6 +106,7 @@
     parallel
     pkgconfig
     pkgsCross
+    plantuml
     postgresql
     pounce
     pulseaudio

tvix/doc/.gitignore

@@ -0,0 +1,2 @@
+*.svg
+*.html

tvix/doc/Makefile

@@ -0,0 +1,12 @@
+all: build
+
+puml:
+	plantuml *.puml -tsvg
+
+html:
+	pandoc *.md -f markdown --self-contained -t html -s -o tvix.html --csl=${CSL}
+
+build: puml html
+
+clean:
+	rm -f *.tex *.pdf *.png *.svg

tvix/doc/default.nix

@@ -0,0 +1,39 @@
+{ pkgs, lib, ... }:
+
+let
+
+  tl = pkgs.texlive.combine {
+    inherit (pkgs.texlive) scheme-medium wrapfig ulem capt-of
+    titlesec preprint enumitem paralist ctex environ svg
+    beamer trimspaces zhnumber changepage framed pdfpages
+    fvextra minted upquote ifplatform xstring;
+  };
+
+  csl = pkgs.fetchurl {
+    name = "numeric.csl";
+    url = "https://gist.githubusercontent.com/bwiernik/8c6f39cf51ceb3a03107/raw/1d75c2d62113ffbba6ed03a47ad99bde86934f2b/APA%2520Numeric";
+    sha256 = "1yfhhnhbzvhrv93baz98frmgsx5y442nzhb0l956l4j35fb0cc3h";
+  };
+
+in pkgs.stdenv.mkDerivation {
+  pname = "tvix-doc";
+  version = "0.1";
+
+  src = lib.cleanSource ./.;
+
+  CSL = csl;
+
+  nativeBuildInputs = [
+    pkgs.pandoc
+    pkgs.plantuml
+    tl
+  ];
+
+  installPhase = ''
+    runHook preInstall
+    mkdir -p $out
+    cp -v *.html $out/
+    runHook postSubmit
+  '';
+
+}