{ pkgs }:

with pkgs;

# emscripten toolchain abstraction for nix
# https://github.com/NixOS/nixpkgs/pull/16208

rec {
  json_c =
    (pkgs.json_c.override {
      stdenv = pkgs.emscriptenStdenv;
    }).overrideAttrs
      (old: {
        nativeBuildInputs = [
          pkg-config
          cmake
        ];
        propagatedBuildInputs = [ zlib ];
        configurePhase = ''
          HOME=$TMPDIR
          mkdir -p .emscriptencache
          export EM_CACHE=$(pwd)/.emscriptencache
          emcmake cmake . $cmakeFlags -DCMAKE_INSTALL_PREFIX=$out -DCMAKE_INSTALL_INCLUDEDIR=$dev/include
        '';
        checkPhase = ''
          echo "================= testing json_c using node ================="

          echo "Compiling a custom test"
          set -x
          emcc -O2 -s EMULATE_FUNCTION_POINTER_CASTS=1 tests/test1.c \
            `pkg-config zlib --cflags` \
            `pkg-config zlib --libs` \
            -I . \
            libjson-c.a \
            -o ./test1.js

          echo "Using node to execute the test which basically outputs an error on stderr which we grep for"
          ${pkgs.lib.getExe pkgs.nodejs-slim} ./test1.js

          set +x
          if [ $? -ne 0 ]; then
            echo "test1.js execution failed -> unit test failed, please fix"
            exit 1;
          else
            echo "test1.js execution seems to work! very good."
          fi
          echo "================= /testing json_c using node ================="
        '';
      });

  libxml2 =
    (pkgs.libxml2.override {
      stdenv = emscriptenStdenv;
      pythonSupport = false;
    }).overrideAttrs
      (old: {
        propagatedBuildInputs = [ zlib ];
        nativeBuildInputs = (old.nativeBuildInputs or [ ]) ++ [ pkg-config ];

        # just override it with nothing so it does not fail
        autoreconfPhase = "echo autoreconfPhase not used...";
        configurePhase = ''
          HOME=$TMPDIR
          mkdir -p .emscriptencache
          export EM_CACHE=$(pwd)/.emscriptencache
          emconfigure ./configure --prefix=$out --without-python
        '';
        checkPhase = ''
          echo "================= testing libxml2 using node ================="

          echo "Compiling a custom test"
          set -x
          emcc -O2 -s EMULATE_FUNCTION_POINTER_CASTS=1 xmllint.o \
          ./.libs/${
            if pkgs.stdenv.hostPlatform.isDarwin then "libxml2.dylib" else "libxml2.a"
          } `pkg-config zlib --cflags` `pkg-config zlib --libs` -o ./xmllint.test.js \
          --embed-file ./test/xmlid/id_err1.xml

          echo "Using node to execute the test which basically outputs an error on stderr which we grep for"
          ${pkgs.lib.getExe pkgs.nodejs-slim} ./xmllint.test.js --noout test/xmlid/id_err1.xml 2>&1 | grep 0bar

          set +x
          if [ $? -ne 0 ]; then
            echo "xmllint unit test failed, please fix this package"
            exit 1;
          else
            echo "since there is no stupid text containing 'foo xml:id' it seems to work! very good."
          fi
          echo "================= /testing libxml2 using node ================="
        '';
      });

  xmlmirror = pkgs.buildEmscriptenPackage rec {
    pname = "xmlmirror";
    version = "0-unstable-2016-06-05";

    buildInputs = [
      libtool
      gnumake
      libxml2
      nodejs
      openjdk
      json_c
    ];
    nativeBuildInputs = [
      pkg-config
      zlib
      autoconf
      automake
    ];

    src = pkgs.fetchFromGitLab {
      owner = "odfplugfest";
      repo = "xmlmirror";
      rev = "4fd7e86f7c9526b8f4c1733e5c8b45175860a8fd";
      hash = "sha256-i+QgY+5PYVg5pwhzcDnkfXAznBg3e8sWH2jZtixuWsk=";
    };

    configurePhase = ''
      rm -f fastXmlLint.js*
      # a fix for ERROR:root:For asm.js, TOTAL_MEMORY must be a multiple of 16MB, was 234217728
      # https://gitlab.com/odfplugfest/xmlmirror/issues/8
      sed -e "s/TOTAL_MEMORY=234217728/TOTAL_MEMORY=268435456/g" -i Makefile.emEnv
      # https://github.com/kripken/emscripten/issues/6344
      # https://gitlab.com/odfplugfest/xmlmirror/issues/9
      sed -e "s/\$(JSONC_LDFLAGS) \$(ZLIB_LDFLAGS) \$(LIBXML20_LDFLAGS)/\$(JSONC_LDFLAGS) \$(LIBXML20_LDFLAGS) \$(ZLIB_LDFLAGS) /g" -i Makefile.emEnv
      # https://gitlab.com/odfplugfest/xmlmirror/issues/11
      sed -e "s/-o fastXmlLint.js/-s EXTRA_EXPORTED_RUNTIME_METHODS='[\"ccall\", \"cwrap\"]' -o fastXmlLint.js/g" -i Makefile.emEnv
      mkdir -p .emscriptencache
      export EM_CACHE=$(pwd)/.emscriptencache
    '';

    buildPhase = ''
      HOME=$TMPDIR
      make -f Makefile.emEnv
    '';

    outputs = [
      "out"
      "doc"
    ];

    installPhase = ''
      mkdir -p $out/share
      mkdir -p $doc/share/${pname}

      cp Demo* $out/share
      cp -R codemirror-5.12 $out/share
      cp fastXmlLint.js* $out/share
      cp *.xsd $out/share
      cp *.js $out/share
      cp *.xhtml $out/share
      cp *.html $out/share
      cp *.json $out/share
      cp *.rng $out/share
      cp README.md $doc/share/${pname}
    '';
    checkPhase = "";

    meta = {
      homepage = "https://gitlab.com/odfplugfest/xmlmirror";
    };
  };

  zlib =
    (pkgs.zlib.override {
      stdenv = pkgs.emscriptenStdenv;
    }).overrideAttrs
      (old: {
        nativeBuildInputs = (old.nativeBuildInputs or [ ]) ++ [ pkg-config ];
        # we need to reset this setting!
        env = (old.env or { }) // {
          NIX_CFLAGS_COMPILE = "";
        };
        dontStrip = true;
        outputs = [ "out" ];
        buildPhase = ''
          emmake make
        '';
        installPhase = ''
          emmake make install
        '';
        checkPhase = ''
          echo "================= testing zlib using node ================="

          echo "Compiling a custom test"
          set -x
          emcc -O2 -s EMULATE_FUNCTION_POINTER_CASTS=1 test/example.c -DZ_SOLO \
          -L. libz.a -I . -o example.js

          echo "Using node to execute the test"
          ${pkgs.lib.getExe pkgs.nodejs-slim} ./example.js

          set +x
          if [ $? -ne 0 ]; then
            echo "test failed for some reason"
            exit 1;
          else
            echo "it seems to work! very good."
          fi
          echo "================= /testing zlib using node ================="
        '';

        postPatch = pkgs.lib.optionalString pkgs.stdenv.hostPlatform.isDarwin ''
          substituteInPlace configure \
            --replace '/usr/bin/libtool' 'ar' \
            --replace 'AR="libtool"' 'AR="ar"' \
            --replace 'ARFLAGS="-o"' 'ARFLAGS="-r"'
        '';
      });

}