{ pkgs, blog-source, web-files, resume }:

with pkgs;
with lib;

let
  protocol = ssl: if ssl then "https://" else "http://";
  gems = settings: bundlerEnv {
    inherit ruby;

    name = "blog-static-flake";
    gemfile = "${settings.src}/Gemfile";
    lockfile = "${settings.src}/Gemfile.lock";
    gemset = ./gemset.nix;
  };

  # --- Building Agda HTML ---
  agdaEnv = agda.withPackages [ agdaPackages.standard-library ];
  agdaHtml = settings:
    let
      # Create content-addresed versions of the scripts in the Nix store to
      # avoid throwing off memoization for unrelated changes.
      agdaBuildScript = builtins.toFile "build-agda-html.rb" (builtins.readFile "${settings.src}/build-agda-html.rb");
      submoduleDataFile = builtins.toFile "submodules.json" (builtins.readFile "${settings.src}/data/submodules.json");
      codeRoot = pkgs.lib.cleanSource "${settings.src}/code";
      agdaCommand = pkgs.lib.escapeShellArg "agda -l standard-library -i . ";
    in
      stdenv.mkDerivation {
        name = "blog-static-agda-html";
        buildInputs = [ ruby agdaEnv ];
        builder = builtins.toFile "builder.sh" "
        source $stdenv/setup
        mkdir -p code $out
        cp -r ${codeRoot}/* code/
        chmod -R u+w code
        ruby ${agdaBuildScript} --data-file=${submoduleDataFile} --target-dir=$out ${agdaCommand}
        ";
      };

  website = settings: stdenv.mkDerivation {
    inherit (settings) src ssl host;
    inherit resume ruby;
    name = "blog-static";
    version = settings.src.rev or "dirty";
    publicPath = settings.path;
    hugoFlags = concatStringsSep " " (
      optionals settings.drafts (singleton "-D") ++
      [ "--baseURL=${protocol settings.ssl + settings.host}" ]
    );
    builder = ./build/builder.sh;
    webFiles = web-files;
    gems = gems settings;
    agdaHtml = agdaHtml settings;
    buildInputs = [
      hugo ruby stork agdaEnv
    ];
  };
in
  {
    english = settings: website {
      inherit (settings) host;
      ssl = settings.ssl or false;
      drafts = settings.drafts or false;
      src = blog-source;
      path = ".";
    };
    virtualHostFor = package:
      {
        "${package.host}" = mkMerge [
          {
            root = package;
          }
          (mkIf (package.ssl) {
            forceSSL = true;
            enableACME = true;
          })
        ];
      };
  }