# SPDX-FileCopyrightText: © 2026 Jeffrey C. Ollie <jeff@ocjtech.us>
# SPDX-License-Identifier: MIT

{
  lib,
  stdenv,
  callPackage,
  zig_0_16,
}:
let
  # Generated by zon2nix from build.zig.zon; regenerate with:
  #   nix run github:jcollie/zon2nix#zon2nix -- --nix=build.zig.zon.nix --16 build.zig.zon
  zigDeps = callPackage ./build.zig.zon.nix { };
in
stdenv.mkDerivation (finalAttrs: {
  pname = "zsmtp";
  # Keep in step with `.version` in build.zig.zon.
  version = "0.0.0";

  # Only what `zig build` actually reads. Narrowing the source this way keeps
  # a stray .zig-cache out of the store, and means edits to the flake, the
  # README or the license texts do not invalidate the derivation.
  src = lib.fileset.toSource {
    root = ./.;
    fileset = lib.fileset.unions [
      ./build.zig
      ./build.zig.zon
      ./src
    ];
  };

  # Provides the configure/build/check/install phases for a `zig build`
  # project, including a writable ZIG_GLOBAL_CACHE_DIR. It passes
  # `-Dcpu=baseline --release=safe`, so the result is a portable ReleaseSafe
  # binary rather than the Debug one `zig build` produces by default.
  nativeBuildInputs = [ zig_0_16 ];

  # All Zig dependencies come from nix, so the sandboxed build never
  # fetches over the network.
  zigBuildFlags = [
    "--system"
    "${zigDeps}"
  ];
  zigCheckFlags = finalAttrs.zigBuildFlags;

  # `zig build test` is fully hermetic: scripted sessions over in-memory
  # readers and writers. Interoperability against real MTAs is covered by
  # the NixOS VM check instead.
  doCheck = true;

  meta = {
    description = "SMTP client and server library for Zig";
    longDescription = ''
      zsmtp is an SMTP client and server library (RFC 5321) for Zig. Both
      sides run over plain std.Io.Reader/std.Io.Writer pairs, making them
      transport-agnostic, and support STARTTLS and implicit TLS, AUTH,
      streamed message bodies, and the SIZE, 8BITMIME, CHUNKING and
      SMTPUTF8 extensions. A small demo CLI for sending and receiving is
      included.
    '';
    homepage = "https://git.jcollie.dev/jeff/zsmtp";
    license = lib.licenses.mit;
    mainProgram = "zsmtp";
    platforms = lib.platforms.unix;
  };
})