{ depot, pkgs, ... }:
let
  inherit (pkgs) prometheus-snmp-exporter curl cacert unzip p7zip;

  hpMibs = pkgs.stdenvNoCC.mkDerivation rec {
    pname = "hp-mibs";
    version = "11.50";

    src = pkgs.fetchurl {
      url = "https://downloads.hpe.com/pub/softlib2/software1/pubsw-linux/p1580676047/v188074/upd11.50mib.tar.gz";
      hash = "sha256:0jxxcirbvhlqrflj0j2vzddqaq7wl7v3g7xi0gcjmxlj6rfkk7i9";
    };
    sourceRoot = ".";

    buildPhase = ":";
    installPhase = ''
      mkdir $out
      cp $(ls | grep -i '\.mib$') $out
    '';
  };

  mibsDrv = pkgs.stdenvNoCC.mkDerivation {
    pname = "prometheus-snmp-mibs";
    version = "lukegb-${prometheus-snmp-exporter.version}";

    outputHashMode = "recursive";
    outputHash = "sha256:1bkp1jlfv9xb9912q58n1x3mvl1xja2ii1jiadykphh64n1d8pvd";

    buildInputs = [
      curl
      p7zip
      prometheus-snmp-exporter
      unzip
    ];
    passthru.hp = hpMibs;

    CURL_OPTS = "--retry 3 --retry-delay 3 --compressed --location --fail";
    SSL_CERT_FILE = "${cacert}/etc/ssl/certs/ca-bundle.crt";

    src = prometheus-snmp-exporter.src;

    unpackPhase = ''
      mkdir $NIX_BUILD_TOP/build
      cp $src/generator/Makefile $NIX_BUILD_TOP/build/Makefile
    '';

    patchPhase = ''
      sed -i $NIX_BUILD_TOP/build/Makefile -e 's,powernet446,powernet451,g' -e 's,POWERNETMIB_446,POWERNETMIB_451,g'
      cat $NIX_BUILD_TOP/build/Makefile
    '';

    buildPhase = ''
      pushd $NIX_BUILD_TOP/build
      mkdir mibs
      make CURL_OPTS="$CURL_OPTS"

      # Additional mibs...
      cp ${hpMibs}/cpqhost.mib ./mibs/
      awk 'BEGIN { p=1 } /INDEX\s+{.+cpqRackServerBladeRack,/ { print "        INDEX { cpqRackServerBladeIndex }"; p=0 } /}/ { if (p==0) { p=2 } } { if (p==1) { print } if (p==2) { p=1 } }' ${hpMibs}/cpqrack.mib > ./mibs/cpqrack.mib
    '';

    installPhase = ''
      cp -R $NIX_BUILD_TOP/build/mibs $out
    '';
  };
in
pkgs.stdenvNoCC.mkDerivation {
  pname = "prometheus-snmp-config";
  version = "lukegb";

  src = prometheus-snmp-exporter.src;
  passthru.mibs = mibsDrv;

  buildInputs = [ prometheus-snmp-exporter ];
  MIBDIRS = mibsDrv;

  unpackPhase = ''
    mkdir $NIX_BUILD_TOP/build
    cat $src/generator/generator.yml ${./generator.yml} > $NIX_BUILD_TOP/build/generator.yml
  '';

  buildPhase = ''
    pushd $NIX_BUILD_TOP/build
    generator generate
  '';

  installPhase = ''
    cp $NIX_BUILD_TOP/build/snmp.yml $out
  '';
}