#!/bin/sh
set -eu

guix_source_dir=${GUIX_SOURCE_DIR:-"$HOME/repos/guix"}
hello_version=${HELLO_VERSION:-2.12.3}
expected_nix_base32=${HELLO_NIX_BASE32:-183a6rxnhixiyykd7qis0y9g9cfqhpkk872a245y3zl28can0pqd}
source_url=${HELLO_SOURCE_URL:-"https://ftp.gnu.org/gnu/hello/hello-$hello_version.tar.gz"}
prefix=${PREFIX:-/usr/local}
cc_bin=${CC_BIN:-cc}
make_bin=${MAKE_BIN:-make}

if [ ! -d "$guix_source_dir/guix" ]; then
  echo "Guix source tree not found at $guix_source_dir" >&2
  exit 1
fi

if [ -n "${GUILE_BIN:-}" ]; then
  guile_bin=$GUILE_BIN
elif command -v guile3 >/dev/null 2>&1; then
  guile_bin=$(command -v guile3)
elif command -v guile-3.0 >/dev/null 2>&1; then
  guile_bin=$(command -v guile-3.0)
else
  echo "Unable to find GUILE_BIN, guile3, or guile-3.0 in PATH" >&2
  exit 1
fi

if [ ! -x "$guile_bin" ]; then
  echo "Guile binary is not executable: $guile_bin" >&2
  exit 1
fi

if ! command -v fetch >/dev/null 2>&1; then
  echo "fetch not found in PATH" >&2
  exit 1
fi
if ! command -v sha256 >/dev/null 2>&1; then
  echo "sha256 not found in PATH" >&2
  exit 1
fi
if ! command -v bsdtar >/dev/null 2>&1; then
  echo "bsdtar not found in PATH" >&2
  exit 1
fi
if ! command -v "$cc_bin" >/dev/null 2>&1; then
  echo "C compiler not found: $cc_bin" >&2
  exit 1
fi
if ! command -v "$make_bin" >/dev/null 2>&1; then
  echo "make tool not found: $make_bin" >&2
  exit 1
fi

jobs=${JOBS:-$(sysctl -n hw.ncpu 2>/dev/null || echo 1)}
guile_prefix=$(CDPATH= cd -- "$(dirname "$guile_bin")/.." && pwd)
guile_lib_dir=$guile_prefix/lib
if [ -e "$guile_lib_dir/libguile-3.0.so.1" ]; then
  if [ -n "${LD_LIBRARY_PATH:-}" ]; then
    export LD_LIBRARY_PATH="$guile_lib_dir:$LD_LIBRARY_PATH"
  else
    export LD_LIBRARY_PATH="$guile_lib_dir"
  fi
fi

cleanup=0
if [ -n "${WORKDIR:-}" ]; then
  workdir=$WORKDIR
  mkdir -p "$workdir"
else
  workdir=$(mktemp -d /tmp/fruix-gnu-hello.XXXXXX)
  cleanup=1
fi

if [ "${KEEP_WORKDIR:-0}" -eq 1 ]; then
  cleanup=0
fi

cleanup_workdir() {
  if [ "$cleanup" -eq 1 ]; then
    rm -rf "$workdir"
  fi
}
trap cleanup_workdir EXIT INT TERM

expected_sha256_hex=$(GUILE_AUTO_COMPILE=0 \
  GUILE_LOAD_PATH="$guix_source_dir${GUILE_LOAD_PATH:+:$GUILE_LOAD_PATH}" \
  "$guile_bin" -c "(use-modules (guix base32) (rnrs bytevectors) (ice-9 format)) (for-each (lambda (b) (format #t \"~2,'0x\" b)) (bytevector->u8-list (nix-base32-string->bytevector (cadr (command-line))))) (newline)" \
  "$expected_nix_base32")

src_tarball=$workdir/hello-$hello_version.tar.gz
src_dir=$workdir/hello-$hello_version
build_dir=$workdir/build
stage_dir=$workdir/stage
metadata_file=$workdir/gnu-hello-build-metadata.txt
configure_log=$workdir/configure.log
build_log=$workdir/build.log
install_log=$workdir/install.log

printf 'Using Guile: %s\n' "$guile_bin"
printf 'Using LD_LIBRARY_PATH: %s\n' "${LD_LIBRARY_PATH:-<unset>}"
printf 'Working directory: %s\n' "$workdir"
printf 'Fetching: %s\n' "$source_url"
fetch -o "$src_tarball" "$source_url"

actual_sha256_hex=$(sha256 -q "$src_tarball")
if [ "$actual_sha256_hex" != "$expected_sha256_hex" ]; then
  echo "sha256 mismatch for $src_tarball" >&2
  echo "expected: $expected_sha256_hex" >&2
  echo "actual:   $actual_sha256_hex" >&2
  exit 1
fi

bsdtar -xf "$src_tarball" -C "$workdir"
mkdir -p "$build_dir" "$stage_dir"

host_triplet=$(sh "$src_dir/build-aux/config.guess")
configure_cmd="CC=$cc_bin $src_dir/configure --prefix=$prefix"

(
  cd "$build_dir"
  env CC="$cc_bin" "$src_dir/configure" --prefix="$prefix"
) >"$configure_log" 2>&1

(
  cd "$build_dir"
  env CC="$cc_bin" "$make_bin" -j"$jobs"
) >"$build_log" 2>&1

(
  cd "$build_dir"
  env CC="$cc_bin" "$make_bin" DESTDIR="$stage_dir" install
) >"$install_log" 2>&1

installed_binary=$stage_dir$prefix/bin/hello
if [ ! -x "$installed_binary" ]; then
  echo "installed hello binary not found: $installed_binary" >&2
  exit 1
fi

hello_output=$(env LC_ALL=C "$installed_binary")
if [ "$hello_output" != "Hello, world!" ]; then
  echo "unexpected hello output: $hello_output" >&2
  exit 1
fi

binary_file=$(file "$installed_binary")
runtime_deps=$(ldd "$installed_binary")
cc_version=$($cc_bin --version | sed -n '1p')
make_version=$($make_bin -V MAKE_VERSION 2>/dev/null || $make_bin --version 2>/dev/null | sed -n '1p' || echo unknown)
uname_string=$(uname -a)

cat >"$metadata_file" <<EOF
hello_version=$hello_version
source_url=$source_url
expected_nix_base32=$expected_nix_base32
expected_sha256_hex=$expected_sha256_hex
actual_sha256_hex=$actual_sha256_hex
guix_source_dir=$guix_source_dir
guile_bin=$guile_bin
cc_bin=$cc_bin
cc_version=$cc_version
make_bin=$make_bin
make_version=$make_version
host_triplet=$host_triplet
configure_command=$configure_cmd
workdir=$workdir
source_dir=$src_dir
build_dir=$build_dir
stage_dir=$stage_dir
installed_binary=$installed_binary
hello_output=$hello_output
binary_file=$binary_file
configure_log=$configure_log
build_log=$build_log
install_log=$install_log
uname=$uname_string
runtime_deps_begin
$runtime_deps
runtime_deps_end
EOF

if [ -n "${METADATA_OUT:-}" ]; then
  mkdir -p "$(dirname "$METADATA_OUT")"
  cp "$metadata_file" "$METADATA_OUT"
fi

printf 'PASS gnu-hello-native-build\n'
printf 'Hello output: %s\n' "$hello_output"
if [ "$cleanup" -eq 0 ]; then
  printf 'Installed binary: %s\n' "$installed_binary"
  printf 'Metadata file: %s\n' "$metadata_file"
else
  printf '%s\n' 'Work directory will be removed on exit (set KEEP_WORKDIR=1 to preserve it).'
fi
if [ -n "${METADATA_OUT:-}" ]; then
  printf 'Copied metadata to: %s\n' "$METADATA_OUT"
fi
printf '%s\n' '--- metadata ---'
cat "$metadata_file"