bitspire/nix/mkAtmApp.nix

# Pure Nix derivation for the Lamassu ATM Electron app.
#
# Uses fetchPnpmDeps + pnpmConfigHook to build entirely inside the Nix sandbox,
# eliminating the need for --impure or a local pnpm install.
#
# Usage (from flake.nix):
#   mkAtmApp = import ./nix/mkAtmApp.nix { inherit pkgs pkgs-unstable; src = self; };
#   atm-app-douro = mkAtmApp { model = "douro"; fiatCode = "GTQ"; };

{ pkgs, pkgs-unstable, src }:

{ model, fiatCode }:

let
  nodejs = pkgs-unstable.nodejs_22;
  pnpm = pkgs-unstable.pnpm_9;
  electron = pkgs-unstable.electron;

  # Electron's Node.js headers — needed to compile native addons (better-sqlite3)
  # that use V8 C++ API (not N-API). Must match the Electron version exactly.
  electronHeaders = pkgs.fetchurl {
    url = "https://electronjs.org/headers/v${electron.version}/node-v${electron.version}-headers.tar.gz";
    hash = "sha256-xtGHm/2Sb0ILU4yUVAqXTRLwzf8yiXxD0zIIrBk8NDw=";
  };
in
pkgs.stdenv.mkDerivation (finalAttrs: {
  pname = "bitspire-atm-app";
  version = "0.1.0";

  inherit src;

  # Filter to only the workspace packages needed for @bitSpire/machine
  pnpmWorkspaces = [
    "@bitSpire/machine..." # "..." suffix = include transitive workspace deps
  ];

  pnpmDeps = pkgs-unstable.fetchPnpmDeps {
    inherit (finalAttrs) pname version src pnpmWorkspaces;
    inherit pnpm;
    fetcherVersion = 3;
    hash = "sha256-Jv5p62E40DtCSZvN/+LTzkhRYJBTyyUOVSBlQyxzcEw=";
  };

  nativeBuildInputs = [
    nodejs
    pnpm
    pkgs-unstable.pnpmConfigHook
    # node-gyp@9.4.1 (pulled in by better-sqlite3) imports distutils, which
    # Python 3.12 removed. pkgs.python3 became 3.12 in nixpkgs 24.11. Pin
    # 3.11 here until pnpm-lock bumps better-sqlite3 to a node-gyp@10+ build.
    pkgs.python311
    pkgs.pkg-config
    pkgs.autoPatchelfHook # patch .node ELF binaries
  ];

  buildInputs = [
    pkgs.sqlite.dev # better-sqlite3
    pkgs.libudev-zero # serialport
    pkgs.stdenv.cc.cc.lib # libstdc++
  ];

  env = {
    ELECTRON_SKIP_BINARY_DOWNLOAD = "1";
    # Vite compile-time variables (baked into the frontend bundle)
    VITE_LAMASSU_MACHINE_MODEL = model;
    VITE_LAMASSU_FIAT_CODE = fiatCode;
  };

  buildPhase = ''
    runHook preBuild

    # Extract Electron's Node.js headers for native addon compilation.
    # better-sqlite3 uses the V8 C++ API (not N-API), so it MUST be compiled
    # against Electron's headers — not Node.js headers — or you get
    # "undefined symbol: _ZN2v811HandleScopeC1EPNS_7IsolateE" at runtime.
    electron_nodedir=$(mktemp -d)
    tar -xzf ${electronHeaders} -C "$electron_nodedir" --strip-components=1

    echo "=== Rebuilding better-sqlite3 against Electron ${electron.version} headers ==="
    pushd node_modules/.pnpm/better-sqlite3@*/node_modules/better-sqlite3
    HOME=$TMPDIR ${nodejs}/bin/npx --yes node-gyp rebuild \
      --nodedir="$electron_nodedir" \
      --arch=x64
    popd

    # Build the Electron app (turbo builds all workspace deps + app)
    pnpm --filter="@bitSpire/machine..." build

    runHook postBuild
  '';

  # Cherry-pick only the runtime node_modules needed by the Electron app.
  # Vite bundles most JS deps — these are native addons and dynamic imports
  # that can't be bundled.
  installPhase = ''
    runHook preInstall

    mkdir -p $out/node_modules/{@lamassu,@serialport}

    # Helper: find a package dir inside the pnpm virtual store.
    # pnpm store dirs look like: node_modules/.pnpm/<name>@<ver>[_<peer-suffix>]/node_modules/<name>
    # The glob must handle version + optional peer suffixes.
    copy_pnpm_pkg() {
      local pkg="$1"   # e.g. "debug" or "@serialport/stream"
      local dest="$2"  # e.g. "$out/node_modules/debug"
      # Convert @scope/name to @scope+name for the .pnpm dir prefix
      local store_prefix="''${pkg/\//-}"   # debug -> debug, @serialport/stream -> @serialport-stream
      store_prefix="''${store_prefix//@/@}"
      # Try globbing; sort to pick the first match deterministically
      local found=$(find node_modules/.pnpm -maxdepth 1 -name "''${store_prefix}@*" -type d | sort | head -1)
      if [ -z "$found" ]; then
        # Fallback: scoped packages use + instead of -
        store_prefix="''${pkg/\//+}"
        found=$(find node_modules/.pnpm -maxdepth 1 -name "''${store_prefix}@*" -type d | sort | head -1)
      fi
      if [ -z "$found" ]; then
        echo "ERROR: could not find pnpm store dir for $pkg" >&2
        exit 1
      fi
      cp -rL "$found/node_modules/$pkg" "$dest"
    }

    # Electron app build outputs
    cp -r apps/machine/dist $out/dist
    cp -r apps/machine/dist-electron $out/dist-electron
    cp apps/machine/package.json $out/package.json

    # --- Native modules (not bundleable by Vite) ---

    # better-sqlite3 (compiled native addon)
    copy_pnpm_pkg better-sqlite3 $out/node_modules/better-sqlite3
    copy_pnpm_pkg bindings $out/node_modules/bindings
    copy_pnpm_pkg file-uri-to-path $out/node_modules/file-uri-to-path

    # @bitSpire/hal (workspace package, dynamically imported for hardware access)
    mkdir -p $out/node_modules/@bitSpire/hal/dist
    cp -rL packages/hal/dist/* $out/node_modules/@bitSpire/hal/dist/
    cp packages/hal/package.json $out/node_modules/@bitSpire/hal/package.json

    # serialport (native RS232 driver chain)
    copy_pnpm_pkg serialport $out/node_modules/serialport
    copy_pnpm_pkg @serialport/stream $out/node_modules/@serialport/stream

    # bindings-cpp: only dist/ + prebuilds/ + package.json (build/ has broken symlinks)
    mkdir -p $out/node_modules/@serialport/bindings-cpp
    bcpp_store=$(find node_modules/.pnpm -maxdepth 1 -name "@serialport+bindings-cpp@*" -type d | sort | head -1)
    cp -rL "$bcpp_store/node_modules/@serialport/bindings-cpp/dist" $out/node_modules/@serialport/bindings-cpp/dist
    cp -rL "$bcpp_store/node_modules/@serialport/bindings-cpp/prebuilds" $out/node_modules/@serialport/bindings-cpp/prebuilds
    cp "$bcpp_store/node_modules/@serialport/bindings-cpp/package.json" $out/node_modules/@serialport/bindings-cpp/package.json

    copy_pnpm_pkg @serialport/bindings-interface $out/node_modules/@serialport/bindings-interface
    copy_pnpm_pkg @serialport/binding-mock $out/node_modules/@serialport/binding-mock

    # Transitive deps of serialport
    copy_pnpm_pkg debug $out/node_modules/debug
    copy_pnpm_pkg ms $out/node_modules/ms
    copy_pnpm_pkg node-addon-api $out/node_modules/node-addon-api
    copy_pnpm_pkg node-gyp-build $out/node_modules/node-gyp-build
    copy_pnpm_pkg lodash-es $out/node_modules/lodash-es

    # serialport parser sub-packages (barrel import requires all 10)
    for parser in \
      parser-byte-length parser-cctalk parser-delimiter \
      parser-inter-byte-timeout parser-packet-length parser-readline \
      parser-ready parser-regex parser-slip-encoder parser-spacepacket; do
      copy_pnpm_pkg "@serialport/$parser" "$out/node_modules/@serialport/$parser"
    done

    runHook postInstall
  '';

  # autoPatchelfHook will scan $out for .node ELF binaries and patch their
  # RPATH to find libstdc++, libudev, libsqlite3, etc.
  # The musl prebuild ships alongside glibc — we only use glibc on NixOS.
  autoPatchelfIgnoreMissingDeps = [ "libc.musl-x86_64.so.1" ];
})