# SPDX-License-Identifier: CC0-1.0

{ nixpkgs, mkDhallManifest }:

let

  inherit (nixpkgs) buildPackages llvmPackages;

  sourceForgeToolchain = nixpkgs.buildPackages.callPackage ./toolchain.nix { };

  stdenvLlvm = let inherit (nixpkgs) stdenv;
  in assert stdenv.cc.isClang; stdenv;

  stdenvGcc = let
    env = nixpkgs.stdenvAdapters.overrideCC nixpkgs.stdenv sourceForgeToolchain;
  in assert env.cc.isGNU; env;

  inherit (stdenvLlvm) lib targetPlatform;
  specs = with targetPlatform;
    [ ]

    ++ lib.optional is32bit "32bit"

    ++ lib.optional is64bit "64bit"

    ++ lib.optional isAarch32 "arm"

    ++ lib.optional isAarch64 "arm_64"

    ++ lib.optional isRiscV "riscv"

    ++ lib.optional isx86 "x86"

    ++ lib.optional isx86_32 "x86_32"

    ++ lib.optional isx86_64 "x86_64";

  toTupConfig = env: attrs:
    let
      tupArch = with env.targetPlatform;

        if isAarch32 then
          "arm"
        else

        if isAarch64 then
          "arm64"
        else

        if isx86_32 then
          "i386"
        else

        if isx86_64 then
          "x86_64"
        else

          abort "unhandled targetPlatform";

      attrs' = with env; { TUP_ARCH = tupArch; } // attrs;

    in with builtins;
    env.mkDerivation {
      name = "tup.config";
      nativeBuildInputs = with nixpkgs.buildPackages; [
        binutils
        pkgconfig
        which
      ];
      text = let
        op = config: name: ''
          ${config}CONFIG_${name}=${getAttr name attrs}
        '';
      in foldl' op "" (attrNames attrs);
      passAsFile = [ "text" ];
      preferLocalBuild = true;
      buildCommand = let
        subst = let
          vars = [ "AR" "NM" ];
          f = other: var:
            other + ''
              echo CONFIG_${var}=`which ''$${var}` >> $out
            '';
        in foldl' f "" vars;
        utils = let
          vars = [ "pkg-config" "objcopy" ];
          f = other: var:
            other + ''
              echo CONFIG_${var}=`which ${var}` >> $out
            '';
        in foldl' f "" vars;
      in ''
        cp $textPath $out
        ${subst}
        ${utils}
      '';
    };

  tupConfigGcc = let
    f = env:
      let prefix = bin: env.cc.targetPrefix + bin;
      in {
        CC = prefix "gcc";
        CXX = prefix "g++";
        LD = prefix "ld";
        OBJCOPY = prefix "objcopy";
        RANLIB = prefix "ranlib";
        READELF = prefix "readelf";
        STRIP = prefix "strip";
        PKGCONFIG = "${nixpkgs.buildPackages.pkgconfig}/bin/pkg-config";

        IS_GCC = "";
        LINUX_HEADERS = buildPackages.glibc.dev;
      };
  in toTupConfig stdenvGcc (f stdenvGcc);

  tupConfigLlvm = let
    f = env:
      let prefix = bin: "${env.cc}/bin/${env.cc.targetPrefix}${bin}";
      in {
        CC = prefix "cc";
        CXX = prefix "c++";
        LD = prefix "ld";
        OBJCOPY = prefix "objcopy";
        OBJDUMP = prefix "objdump";
        RANLIB = prefix "ranlib";
        READELF = prefix "readelf";
        STRIP = prefix "strip";
        PKGCONFIG = "${nixpkgs.buildPackages.pkgconfig}/bin/pkg-config";

        IS_LLVM = "";
        LIBCXXABI = llvmPackages.libcxxabi;
        LIBCXX = llvmPackages.libcxx;
        LIBUNWIND_BAREMETAL =
          llvmPackages.libunwind.override { isBaremetal = true; };
        LIBUNWIND = llvmPackages.libunwind;
        LINUX_HEADERS = buildPackages.glibc.dev;
      };
  in toTupConfig stdenvLlvm (f stdenvLlvm);

  src = nixpkgs.fetchgit {
    url = "https://git.sr.ht/~ehmry/genode";
    rev = "f91c4824977ef907a86c6a5980d3cb556f6b8af3";
    sha256 = "18hmklnw092myr1yza0v1k7zi3dnc4x64kwlg46pf2rgnijxyhqr";
  };

  buildRepo = { env, repo, repoInputs }:
    env.mkDerivation {
      pname = repo;
      version = "19.11";
      inherit repo specs src;

      nativeBuildInputs = repoInputs;
      # This is wrong, why does pkg-config not collect buildInputs?

      propagatedNativeBuildInputs = repoInputs;

      depsBuildBuild = with buildPackages; [ llvm pkgconfig tup ];

      tupConfig = if env.cc.isGNU then
        tupConfigGcc
      else if env.cc.isClang then
        tupConfigLlvm
      else
        throw "no Tup config for this stdenv";

      configurePhase = ''
        # Configure Tup
        set -v
        install -m666 $tupConfig tup.config
        echo CONFIG_NIX_OUTPUTS_OUT=$out >> tup.config
        echo CONFIG_NIX_OUTPUTS_DEV=$out >> tup.config

        # Disable other repos
        for R in repos/*; do
          [ "$R" != "repos/$repo" ] && find $R -name Tupfile -delete
        done

        # Scan repository and generate script
        tup init
        tup generate buildPhase.sh

        # Redirect artifacts to Nix store
        mkdir -p $out/lib $out/include
        ln -s $out out
        ln -s $out dev
      '';

      buildPhase = ''
        test -d repos/$repo/src/ld && cp -rv repos/$repo/src/ld $out/
        pushd .
        set -v
        source buildPhase.sh
        set +v
        popd
      '';

      installPhase = ''
        # Populate the "dev" headers
        if [ -d "repos/$repo/include" ]; then
          for DIR in repos/$repo/include; do
            for SPEC in $specs; do
              if [ -d $DIR/spec/$SPEC ]; then
                cp -r $DIR/spec/$SPEC/* $out/include
                rm -r $DIR/spec/$SPEC
              fi
            done
            rm -rf $DIR/spec
            cp -r $DIR $out/
          done
        fi

        touch $out/.genode
        for pc in $out/lib/pkgconfig/*.pc; do
          sed -e "s|^Libs: |Libs: -L$out/lib |" -i $pc
        done
      '';

      meta = with env.lib; {
        description =
          "The Genode operation system framework (${repo} repository).";
        homepage = "https://genode.org/";
        license = licenses.agpl3;
        maintainers = [ maintainers.ehmry ];
      };

    };

  buildRepo' = { ... }@args:
    let drv = buildRepo ({ env = stdenvGcc; } // args);
    in { manifest = mkDhallManifest drv; } // drv;

  drvs = rec {

    base = buildRepo' {
      repo = "base";
      repoInputs = [ ];
    };

    base-linux = buildRepo' {
      repo = "base-linux";
      repoInputs = [ base ];
    };

    base-nova = buildRepo' {
      repo = "base-nova";
      repoInputs = [ base ];
    };

    os = buildRepo' {
      repo = "os";
      repoInputs = [ base ];
    };

    gems = buildRepo' {
      repo = "gems";
      repoInputs = [ base os ];
    };

    inherit stdenvGcc stdenvLlvm tupConfigGcc tupConfigLlvm;

  };

  manifest = with builtins;
    let
      repoDrvs = filter (drv: typeOf drv == "set" && hasAttr "repo" drv && hasAttr "manifest" drv)
        (attrValues drvs);
      records = map (drv: "${drv.repo}=${drv.manifest}") repoDrvs;
      text = "{" + builtins.concatStringsSep "," records + "}";
    in nixpkgs.writeTextFile {
      name = "genode.manifest.dhall";
      inherit text;
    };

in drvs // manifest