{ pkgs, root }:
pkgs.stdenv.mkDerivation {
  name = "grimu-r-website";

  src = pkgs.lib.cleanSourceWith {
    src = root;
    filter = path: type:
      let
        baseName = baseNameOf path;
        relativePath = pkgs.lib.removePrefix (toString root + "/") (toString path);
      in
        baseName == "README.org" ||
        relativePath == "website" ||
        pkgs.lib.hasPrefix "website/" relativePath;
  };
  buildInputs = [ pkgs.pandoc ];

  buildPhase = ''
    cp $src/website/pandoc-template.html ./
    mkdir -p ./html/doc
    cp $src/website/favicon.ico ./html/
    cp $src/website/llms.txt ./html/

    if [ -d "$src/website/doc" ]; then
      echo '<nav class="sidebar"><ul>' > docs-nav.html
      
      for file in $(find $src/website/doc -name "*.org" -type f | sort); do
        basename=$(basename "$file" .org)
        title=$(grep -m1 -i "^#+TITLE:" "$file" | sed 's/^#+TITLE:[[:space:]]*//I' || echo "$basename")
        echo "<li><a href=\"$basename.html\">$title</a></li>" >> docs-nav.html
      done
      
      echo '</ul></nav>' >> docs-nav.html
    fi

    if [ -d "$src/website/doc" ]; then
      for file in $src/website/doc/*.org; do
        basename=$(basename "$file" .org)
        pandoc \
          --template=./pandoc-template.html \
          --include-before-body=./docs-nav.html \
          --shift-heading-level-by=1 \
          --section-divs \
          -M document-css=false \
          "$file" \
          -o "./html/doc/$basename.html"
      done
    fi

    pandoc \
      --template=./pandoc-template.html \
      --shift-heading-level-by=1 \
      --section-divs \
      -M document-css=false \
      $src/README.org \
      -o html/index.html

    pandoc \
      --template=./pandoc-template.html \
      --shift-heading-level-by=1 \
      --section-divs \
      -M document-css=false \
      $src/website/pitch.org \
      -o html/pitch.html
  '';

  installPhase = ''
    mkdir -p $out/html
    mkdir -p $out/bin
    cp -r ./html $out/

    cat > $out/bin/grimu-r-website <<EOF
#!/usr/bin/env bash
${pkgs.python3}/bin/python3 -m http.server --directory "$out/html"
EOF
    chmod +x $out/bin/grimu-r-website
  '';
}