{ depot, pkgs, lib, ... }:

let
  # Seed a tvix-store with the tvix docs, then start a VM, ask it to list all
  # files in /nix/store, and ensure the store path is present, which acts as a
  # nice smoketest.
  mkBootTest =
    { blobServiceAddr ? "memory://"
    , directoryServiceAddr ? "memory://"
    , pathInfoServiceAddr ? "memory://"


      # The path to import.
    , path

      # Whether the path should be imported as a closure.
      # If false, importPathName must be specified.
    , isClosure ? false
    , importPathName ? null

    }:

      assert isClosure -> importPathName == null;
      assert (!isClosure) -> importPathName != null;

      pkgs.stdenv.mkDerivation {
        name = "run-vm";

        nativeBuildInputs = [
          depot.tvix.store
          depot.tvix.boot.runVM
        ] ++ lib.optionals isClosure [
          depot.tvix.nar-bridge
          pkgs.curl
          pkgs.parallel
          pkgs.xz.bin
        ];
        buildCommand = ''
          touch $out

          # Start the tvix daemon, listening on a unix socket.
          BLOB_SERVICE_ADDR=${blobServiceAddr} \
            DIRECTORY_SERVICE_ADDR=${directoryServiceAddr} \
            PATH_INFO_SERVICE_ADDR=${pathInfoServiceAddr} \
            tvix-store \
              --otlp=false \
              daemon -l $PWD/tvix-store.sock &

          # Wait for the socket to be created.
          while [ ! -e $PWD/tvix-store.sock ]; do sleep 1; done

          # Export env vars so that subsequent tvix-store commands will talk to
          # our tvix-store daemon over the unix socket.
          export BLOB_SERVICE_ADDR=grpc+unix://$PWD/tvix-store.sock
          export DIRECTORY_SERVICE_ADDR=grpc+unix://$PWD/tvix-store.sock
          export PATH_INFO_SERVICE_ADDR=grpc+unix://$PWD/tvix-store.sock
        '' + lib.optionalString (!isClosure) ''
          echo "Importing ${path} into tvix-store with name ${importPathName}…"
          cp -R ${path} ${importPathName}
          outpath=$(tvix-store import ${importPathName})

          echo "imported to $outpath"
        '' + lib.optionalString (isClosure) ''
          echo "Starting nar-bridge…"
          nar-bridge-http \
            --otlp=false \
            --store-addr=unix://$PWD/tvix-store.sock \
            --listen-addr=$PWD/nar-bridge.sock &

          # Wait for the socket to be created.
          while [ ! -e $PWD/nar-bridge.sock ]; do sleep 1; done

          # Upload. We can't use nix copy --to http://…, as it wants access to the nix db.
          # However, we can use mkBinaryCache to assemble .narinfo and .nar.xz to upload,
          # and then drive a HTTP client ourselves.
          to_upload=${pkgs.mkBinaryCache { rootPaths = [path];}}

          # Upload all NAR files (with some parallelism).
          # As mkBinaryCache produces them xz-compressed, unpack them on the fly.
          # nar-bridge doesn't care about the path we upload *to*, but a
          # subsequent .narinfo upload need to refer to its contents (by narhash).
          echo -e "Uploading NARs… "
          ls -d $to_upload/nar/*.nar.xz | parallel 'xz -d < {} | curl -s -T - --unix-socket $PWD/nar-bridge.sock http://localhost:9000/nar/$(basename {} | cut -d "." -f 1).nar'
          echo "Done."

          # Upload all NARInfo files.
          # FUTUREWORK: This doesn't upload them in order, and currently relies
          # on PathInfoService not doing any checking.
          # In the future, we might want to make this behaviour configurable,
          # and disable checking here, to keep the logic simple.
          ls -d $to_upload/*.narinfo | parallel 'curl -s -T - --unix-socket $PWD/nar-bridge.sock http://localhost:9000/$(basename {}) < {}'
        '' + ''
          # Invoke a VM using tvix as the backing store, ensure the outpath appears in its listing.

          CH_CMDLINE="tvix.find" run-tvix-vm 2>&1 | tee output.txt
          grep ${path} output.txt
        '';
        requiredSystemFeatures = [ "kvm" ];
      };
in
depot.nix.readTree.drvTargets
{
  docs-memory = (mkBootTest {
    path = ../../docs;
    importPathName = "docs";
  });
  docs-sled = (mkBootTest {
    blobServiceAddr = "sled://$PWD/blobs.sled";
    directoryServiceAddr = "sled://$PWD/directories.sled";
    pathInfoServiceAddr = "sled://$PWD/pathinfo.sled";
    path = ../../docs;
    importPathName = "docs";
  });
  docs-objectstore-local = (mkBootTest {
    blobServiceAddr = "objectstore+file://$PWD/blobs";
    path = ../../docs;
    importPathName = "docs";
  });

  closure-tvix = (mkBootTest {
    blobServiceAddr = "objectstore+file://$PWD/blobs";
    path = depot.tvix.store;
    isClosure = true;
  });
}