{ stdenv, lib, buildEnv, buildGoPackage, fetchFromGitHub, makeWrapper, coreutils
, runCommand, runtimeShell, writeText, terraform-providers, fetchpatch }:

let
  goPackagePath = "github.com/hashicorp/terraform";

  generic = { version, sha256, ... }@attrs:
    let attrs' = builtins.removeAttrs attrs [ "version" "sha256" ];
    in buildGoPackage ({
      name = "terraform-${version}";

      inherit goPackagePath;

      src = fetchFromGitHub {
        owner = "hashicorp";
        repo = "terraform";
        rev = "v${version}";
        inherit sha256;
      };

      postPatch = ''
        # speakeasy hardcodes /bin/stty https://github.com/bgentry/speakeasy/issues/22
        substituteInPlace vendor/github.com/bgentry/speakeasy/speakeasy_unix.go \
          --replace "/bin/stty" "${coreutils}/bin/stty"
      '';

      postInstall = ''
        # remove all plugins, they are part of the main binary now
        for i in $out/bin/*; do
          if [[ $(basename $i) != terraform ]]; then
            rm "$i"
          fi
        done
      '';

      preCheck = ''
        export HOME=$TMP
      '';

      meta = with stdenv.lib; {
        description =
          "Tool for building, changing, and versioning infrastructure";
        homepage = "https://www.terraform.io/";
        license = licenses.mpl20;
        maintainers = with maintainers; [
          Chili-Man
          babariviere
          kalbasit
          marsam
          peterhoeg
          timstott
          zimbatm
        ];
      };
    } // attrs');

  pluggable = terraform:
    let
      withPlugins = plugins:
        let
          actualPlugins = plugins terraform.plugins;

          # Make providers available in Terraform 0.13 and 0.12 search paths.
          pluginDir = lib.concatMapStrings (pl: let
            inherit (pl) repo version GOOS GOARCH;
            inherit (pl.passthru) providerSourceAddress;

            shim = writeText "shim" ''
              #!${runtimeShell}
              exec ${pl}/bin/${repo}_v${version} \$@
            '';
            in ''
              TF_0_13_PROVIDER_PATH=$out/plugins/${providerSourceAddress}/${version}/${GOOS}_${GOARCH}/${repo}_v${version}
              mkdir -p "$(dirname $TF_0_13_PROVIDER_PATH)"

              cp ${shim} "$TF_0_13_PROVIDER_PATH"
              chmod +x "$TF_0_13_PROVIDER_PATH"

              TF_0_12_PROVIDER_PATH=$out/plugins/${repo}_v${version}

              cp ${shim} "$TF_0_12_PROVIDER_PATH"
              chmod +x "$TF_0_12_PROVIDER_PATH"
          ''
          ) actualPlugins;

          # Wrap PATH of plugins propagatedBuildInputs, plugins may have runtime dependencies on external binaries
          wrapperInputs = lib.unique (lib.flatten
            (lib.catAttrs "propagatedBuildInputs"
              (builtins.filter (x: x != null) actualPlugins)));

          passthru = {
            withPlugins = newplugins:
              withPlugins (x: newplugins x ++ actualPlugins);
            full = withPlugins lib.attrValues;

            # Ouch
            overrideDerivation = f:
              (pluggable (terraform.overrideDerivation f)).withPlugins plugins;
            overrideAttrs = f:
              (pluggable (terraform.overrideAttrs f)).withPlugins plugins;
            override = x:
              (pluggable (terraform.override x)).withPlugins plugins;
          };
          # Don't bother wrapping unless we actually have plugins, since the wrapper will stop automatic downloading
          # of plugins, which might be counterintuitive if someone just wants a vanilla Terraform.
        in if actualPlugins == [ ] then
          terraform.overrideAttrs
          (orig: { passthru = orig.passthru // passthru; })
        else
          lib.appendToName "with-plugins" (stdenv.mkDerivation {
            inherit (terraform) name;
            buildInputs = [ makeWrapper ];

            buildCommand = pluginDir + ''
              mkdir -p $out/bin/
              makeWrapper "${terraform}/bin/terraform" "$out/bin/terraform" \
                --set NIX_TERRAFORM_PLUGIN_DIR $out/plugins \
                --prefix PATH : "${lib.makeBinPath wrapperInputs}"
            '';

            inherit passthru;
          });
    in withPlugins (_: [ ]);

  plugins = removeAttrs terraform-providers [
    "override"
    "overrideDerivation"
    "recurseForDerivations"
  ];
in rec {
  terraform_0_11 = pluggable (generic {
    version = "0.11.14";
    sha256 = "1bzz5wy13gh8j47mxxp6ij6yh20xmxd9n5lidaln3mf1bil19dmc";
    patches = [ ./provider-path.patch ];
    passthru = { inherit plugins; };
  });

  terraform_0_11-full = terraform_0_11.full;

  terraform_0_12 = pluggable (generic {
    version = "0.12.29";
    sha256 = "18i7vkvnvfybwzhww8d84cyh93xfbwswcnwfrgvcny1qwm8rsaj8";
    patches = [
        ./provider-path.patch
        (fetchpatch {
            name = "fix-mac-mojave-crashes.patch";
            url = "https://github.com/hashicorp/terraform/commit/cd65b28da051174a13ac76e54b7bb95d3051255c.patch";
            sha256 = "1k70kk4hli72x8gza6fy3vpckdm3sf881w61fmssrah3hgmfmbrs";
        }) ];
    passthru = { inherit plugins; };
  });

  terraform_0_13 = pluggable (generic {
    version = "0.13.4";
    sha256 = "1yvcz14q82v9jq4b9knn6wgnhlhrsz2ncvxv4lh9y1avn56chsqc";
    patches = [ ./provider-path.patch ];
    passthru = { inherit plugins; };
  });

  # Tests that the plugins are being used. Terraform looks at the specific
  # file pattern and if the plugin is not found it will try to download it
  # from the Internet. With sandboxing enable this test will fail if that is
  # the case.
  terraform_plugins_test = let
    mainTf = writeText "main.tf" ''
      resource "random_id" "test" {}
    '';
    terraform = terraform_0_11.withPlugins (p: [ p.random ]);
    test =
      runCommand "terraform-plugin-test" { buildInputs = [ terraform ]; } ''
        set -e
        # make it fail outside of sandbox
        export HTTP_PROXY=http://127.0.0.1:0 HTTPS_PROXY=https://127.0.0.1:0
        cp ${mainTf} main.tf
        terraform init
        touch $out
      '';
  in test;

}