#!/usr/bin/env bash
# Runs one VM test on a Mac, where the guest is Linux and the host is not.
#
#   scripts/linux/vm-mac NAME [driver arguments]
#
# The guest's closure is built on a Linux builder, copied back, and the test driver then runs
# on the Mac under HVF. The driver is run directly, not through `nix build`, because the nix
# sandbox on macOS cannot give QEMU the hypervisor. Artifacts (screenshots, logs) land in
# `.vm/out/NAME`.
#
# The builder is yours: set KOMOREBI_BUILDER to its store URL (for example
# `ssh-ng://builder@localhost`) and, if it needs them, NIX_SSHOPTS. docs/linux/dev/vm-tests.md
# says what a builder has to be.
set -euo pipefail

name="${1:?usage: scripts/linux/vm-mac NAME [driver arguments]}"
shift
builder="${KOMOREBI_BUILDER:?set KOMOREBI_BUILDER to the store URL of a Linux builder}"
cd "$(dirname "$0")/../.."
attr="legacyPackages.aarch64-darwin.vm.$name"
test="path:$PWD#$attr"
# a git checkout is a flake source without its untracked files (.vm, target); the repository may be
# a subdirectory of a bigger git repository, whose toplevel is not $PWD
if top=$(git rev-parse --show-toplevel 2> /dev/null); then
  if [ "$top" = "$PWD" ]; then
    test="git+file://$PWD#$attr"
  else
    test="git+file://$top?dir=${PWD#"$top"/}#$attr"
  fi
fi

echo "== building the guests on $builder"
nix eval --json "$test.nodes" --apply 'nodes: builtins.mapAttrs (_: node: node.system.build.toplevel.drvPath) nodes' |
  jq -r '.[]' |
  while read -r drv; do
    out=$(nix build "$drv^out" --eval-store auto --store "$builder" --no-link --print-out-paths)
    nix copy --from "$builder" --substitute-on-destination --no-check-sigs "$out"
  done

echo "== building the driver"
driver=$(nix build "$test.driver" --builders '' --no-link --print-out-paths)

out="$PWD/.vm/out/$name"
mkdir -p "$out"
echo "== running $name (artifacts in $out)"
cd "$out"
exec "$driver/bin/nixos-test-driver" -o . "$@"