# Mnemosyne memory provider for Hermes on mars — packaged for real (Nix).
#
# Why derivations instead of a runtime side-venv: the official Hermes image
# vendors its own Python and stays off-limits to pip (no pip module, PEP 668),
# and a runtime venv built host-side breaks twice over inside the container:
# the venv's pyvenv.cfg records a /nix/store python home the container never
# mounts, and a plugins symlink with an absolute host path points nowhere
# from /opt/data. Building here means nothing is fetched at boot, nothing
# under the provider's control is writable from inside the container, and
# the closure is as reproducible as the rest of the host.
#
# Package set (one shared site-packages — the plugin wrapper imports its
# sibling `mnemosyne` core package, so withPackages, not separate envs):
#
#   mnemosyne-memory  core engine: SQLite/FTS5 storage, recall, tools.
#                     Base deps only (PyYAML); the optional extras (llm,
#                     embeddings via fastembed/onnxruntime, mcp, sync) are
#                     deliberately NOT pulled — recall uses the bundled FTS5
#                     lexical path, and the heavyweight ML stack (~hundreds of
#                     MB, live network on first vector use) buys nothing for
#                     a first deployment. Adding the embeddings extra later
#                     is pinning fastembed + sqlite-vec here.
#   mnemosyne-hermes  the wrapper Hermes discovers under $HERMES_HOME/plugins
#                     (installs itself as package `hermes_memory_provider`).
#                     Hard dependency: mnemosyne-memory, PyYAML.
#
# Platform note: both sdists are pure Python (build no C extensions), so
# nothing here constrains the host arch beyond the interpreter itself.
{
  python3,
  fetchPypi,
}:

let
  python = python3;

  mnemosyneMemory = python.pkgs.buildPythonPackage rec {
    pname = "mnemosyne-memory";
    version = "3.15.1";
    pyproject = true;

    src = fetchPypi {
      inherit pname version;
      sha256 = "sha256-lspUMxc0pUSkhSUrNdiiO5OJ1NMC/S853EYSanXtXKM=";
    };

    build-system = with python.pkgs; [ setuptools ];

    # Base dependency set — everything else in the upstream metadata is an
    # optional extra (llm / embeddings / mcp / sync / test / dev) and is not
    # installed; see the file-level comment.
    dependencies = with python.pkgs; [ pyyaml ];

    doCheck = false; # upstream tests want a live Hermes + LLM key present
    pythonImportsCheck = [ "mnemosyne" ];
  };

  mnemosyneHermes = python.pkgs.buildPythonPackage rec {
    pname = "mnemosyne-hermes";
    version = "0.5.0";
    pyproject = true;

    src = fetchPypi {
      inherit pname version;
      sha256 = "sha256-CzEvnUw5oPFtT5bHQQ/GBdy2C/E7qShQn32irIRYKqw=";
    };

    build-system = with python.pkgs; [ setuptools ];

    # The wrapper declares `mnemosyne-memory[embeddings]>=3.11.1` on PyPI, but
    # the embeddings extra is only consulted when vector recall is enabled
    # (see above) — pass the core dependency explicitly rather than dragging
    # in onnxruntime for nothing.
    dependencies = [ mnemosyneMemory ] ++ (with python.pkgs; [ pyyaml ]);

    doCheck = false;
    pythonImportsCheck = [ "hermes_memory_provider" ];
  };

  # The exposed value is the python env itself (a store path mounted :ro).
  # Hermes only needs the site-packages dir inside it; `sitePackages` is a
  # passthru the python interpreter derivation (and hence withPackages envs)
  # exposes, so the caller uses `${env.sitePackages}` instead of guessing
  # the python version in a path literal.
in
python.withPackages (_: [ mnemosyneMemory mnemosyneHermes ])