{ pkgs
, lib
, stdenv
, fetchFromGitHub
, makeWrapper
, gawk
, gnum4
, gnused
, libxml2
, libxslt
, ncurses
, openssl
, perl
, runtimeShell
, autoconf
, openjdk11 ? null # javacSupport
, unixODBC ? null # odbcSupport
, libGL ? null
, libGLU ? null
, wxGTK ? null
, xorg ? null
, ex_doc ? null
, parallelBuild ? false
, systemd
, wxSupport ? true
, ex_docSupport ? false
, systemdSupport ? lib.meta.availableOn stdenv.hostPlatform systemd # systemd support in epmd
  # updateScript deps
, writeScript
, common-updater-scripts
, coreutils
, git
, wrapGAppsHook3
}:
{ baseName ? "erlang"
, version
, sha256 ? null
, rev ? "OTP-${version}"
, src ? fetchFromGitHub { inherit rev sha256; owner = "erlang"; repo = "otp"; }
, enableHipe ? true
, enableDebugInfo ? false
, enableThreads ? true
, enableSmpSupport ? true
, enableKernelPoll ? true
, javacSupport ? false
, javacPackages ? [ openjdk11 ]
, odbcSupport ? false
, odbcPackages ? [ unixODBC ]
, opensslPackage ? openssl
, wxPackages ? [ libGL libGLU wxGTK xorg.libX11 wrapGAppsHook3 ]
, preUnpack ? ""
, postUnpack ? ""
, patches ? [ ]
, patchPhase ? ""
, prePatch ? ""
, postPatch ? ""
, configureFlags ? [ ]
, configurePhase ? ""
, preConfigure ? ""
, postConfigure ? ""
, buildPhase ? ""
, preBuild ? ""
, postBuild ? ""
, installPhase ? ""
, preInstall ? ""
, postInstall ? ""
, installTargets ? if ((lib.versionOlder version "27.0") || ex_docSupport) then [ "install" "install-docs" ] else [ "install" ]
, checkPhase ? ""
, preCheck ? ""
, postCheck ? ""
, fixupPhase ? ""
, preFixup ? ""
, postFixup ? ""
, meta ? { }
}:

assert wxSupport -> (if stdenv.hostPlatform.isDarwin
then wxGTK != null
else libGL != null && libGLU != null && wxGTK != null && xorg != null);

assert odbcSupport -> unixODBC != null;
assert javacSupport -> openjdk11 != null;
assert ex_docSupport -> ex_doc != null;

let
  inherit (lib) optional optionals optionalAttrs optionalString;
  wxPackages2 = if stdenv.hostPlatform.isDarwin then [ wxGTK ] else wxPackages;

in
stdenv.mkDerivation ({
  # name is used instead of pname to
  # - not have to pass pnames as argument
  # - have a separate pname for erlang (main module)
  name = "${baseName}"
    + optionalString javacSupport "_javac"
    + optionalString odbcSupport "_odbc"
    + "-${version}";

  inherit src version;

  LANG = "C.UTF-8";

  nativeBuildInputs = [ autoconf makeWrapper perl gnum4 libxslt libxml2 ];

  buildInputs = [ ncurses opensslPackage ]
    ++ optionals wxSupport wxPackages2
    ++ optionals odbcSupport odbcPackages
    ++ optionals javacSupport javacPackages
    ++ optional systemdSupport systemd
    ++ optionals stdenv.hostPlatform.isDarwin (with pkgs.darwin.apple_sdk.frameworks; [ AGL Carbon Cocoa WebKit ]);

  debugInfo = enableDebugInfo;

  # On some machines, parallel build reliably crashes on `GEN    asn1ct_eval_ext.erl` step
  enableParallelBuilding = parallelBuild;

  postPatch = ''
    patchShebangs make

    ${postPatch}
  '' + optionalString (lib.versionOlder "25" version) ''
    substituteInPlace lib/os_mon/src/disksup.erl \
      --replace-fail '"sh ' '"${runtimeShell} '
  '';

  # For OTP 27+ we need ex_doc to build the documentation
  # When ex_docSupport is enabled, grab the raw ex_doc executable from the ex_doc
  # derivation. Next, patch the first line to use the escript that will be
  # built during the build phase of this derivation. Finally, building the
  # documentation requires the erlang-logo.png asset.
  preConfigure = ''
    ./otp_build autoconf
  '' + optionalString ex_docSupport ''
    mkdir -p $out/bin
    cp ${ex_doc}/bin/.ex_doc-wrapped $out/bin/ex_doc
    sed -i "1 s:^.*$:#!$out/bin/escript:" $out/bin/ex_doc
    export EX_DOC=$out/bin/ex_doc

    mkdir -p $out/lib/erlang/system/doc/assets
    cp $src/system/doc/assets/erlang-logo.png $out/lib/erlang/system/doc/assets
  '';

  configureFlags = [ "--with-ssl=${lib.getOutput "out" opensslPackage}" ]
    ++ [ "--with-ssl-incl=${lib.getDev opensslPackage}" ] # This flag was introduced in R24
    ++ optional enableThreads "--enable-threads"
    ++ optional enableSmpSupport "--enable-smp-support"
    ++ optional enableKernelPoll "--enable-kernel-poll"
    ++ optional enableHipe "--enable-hipe"
    ++ optional javacSupport "--with-javac"
    ++ optional odbcSupport "--with-odbc=${unixODBC}"
    ++ optional wxSupport "--enable-wx"
    ++ optional systemdSupport "--enable-systemd"
    ++ optional stdenv.hostPlatform.isDarwin "--enable-darwin-64bit"
    # make[3]: *** [yecc.beam] Segmentation fault: 11
    ++ optional (stdenv.hostPlatform.isDarwin && stdenv.hostPlatform.isx86_64) "--disable-jit"
    ++ configureFlags;

  # install-docs will generate and install manpages and html docs
  # (PDFs are generated only when fop is available).

  postInstall = ''
    ln -s $out/lib/erlang/lib/erl_interface*/bin/erl_call $out/bin/erl_call

    ${postInstall}
  '';

  # Some erlang bin/ scripts run sed and awk
  postFixup = ''
    wrapProgram $out/lib/erlang/bin/erl --prefix PATH ":" "${gnused}/bin/"
    wrapProgram $out/lib/erlang/bin/start_erl --prefix PATH ":" "${lib.makeBinPath [ gnused gawk ]}"
  '';

  passthru = {
    updateScript =
      let major = builtins.head (builtins.splitVersion version);
      in
      writeScript "update.sh" ''
        #!${stdenv.shell}
        set -ox errexit
        PATH=${lib.makeBinPath [ common-updater-scripts coreutils git gnused ]}
        latest=$(list-git-tags --url=https://github.com/erlang/otp.git | sed -n 's/^OTP-${major}/${major}/p' | sort -V | tail -1)
        if [ "$latest" != "${version}" ]; then
          nixpkgs="$(git rev-parse --show-toplevel)"
          nix_file="$nixpkgs/pkgs/development/interpreters/erlang/${major}.nix"
          update-source-version ${baseName}R${major} "$latest" --version-key=version --print-changes --file="$nix_file"
        else
          echo "${baseName}R${major} is already up-to-date"
        fi
      '';
  };

  meta = with lib; ({
    homepage = "https://www.erlang.org/";
    downloadPage = "https://www.erlang.org/download.html";
    description = "Programming language used for massively scalable soft real-time systems";

    longDescription = ''
      Erlang is a programming language used to build massively scalable
      soft real-time systems with requirements on high availability.
      Some of its uses are in telecoms, banking, e-commerce, computer
      telephony and instant messaging. Erlang's runtime system has
      built-in support for concurrency, distribution and fault
      tolerance.
    '';

    platforms = platforms.unix;
    maintainers = teams.beam.members;
    license = licenses.asl20;
  } // meta);
}
// optionalAttrs (preUnpack != "") { inherit preUnpack; }
// optionalAttrs (postUnpack != "") { inherit postUnpack; }
// optionalAttrs (patches != [ ]) { inherit patches; }
// optionalAttrs (prePatch != "") { inherit prePatch; }
// optionalAttrs (patchPhase != "") { inherit patchPhase; }
// optionalAttrs (configurePhase != "") { inherit configurePhase; }
// optionalAttrs (preConfigure != "") { inherit preConfigure; }
// optionalAttrs (postConfigure != "") { inherit postConfigure; }
// optionalAttrs (buildPhase != "") { inherit buildPhase; }
// optionalAttrs (preBuild != "") { inherit preBuild; }
// optionalAttrs (postBuild != "") { inherit postBuild; }
// optionalAttrs (checkPhase != "") { inherit checkPhase; }
// optionalAttrs (preCheck != "") { inherit preCheck; }
// optionalAttrs (postCheck != "") { inherit postCheck; }
// optionalAttrs (installPhase != "") { inherit installPhase; }
// optionalAttrs (installTargets != [ ]) { inherit installTargets; }
// optionalAttrs (preInstall != "") { inherit preInstall; }
// optionalAttrs (fixupPhase != "") { inherit fixupPhase; }
// optionalAttrs (preFixup != "") { inherit preFixup; }
// optionalAttrs (postFixup != "") { inherit postFixup; }
)