#!/usr/bin/env bash
set -euo pipefail

ROOT=$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)
HELPER="$ROOT/tools/in-dev-shell"
REAL_JUST=$(command -v just)
TMP=$(mktemp -d)
trap 'rm -rf "$TMP"' EXIT

fail() {
    echo "FAIL: $*" >&2
    exit 1
}

assert_args() {
    local actual=$1
    shift
    printf '%s\0' "$@" > "$TMP/expected.args"
    cmp "$TMP/expected.args" "$actual" || fail "unexpected argv in $actual"
}

mkdir -p "$TMP/bin" "$TMP/no-nix" "$TMP/ldraw" "$TMP/runtime"
ln -s "$(command -v bash)" "$TMP/bin/bash"
ln -s "$(command -v jj)" "$TMP/bin/jj"
ln -s "$(command -v tar)" "$TMP/bin/tar"
ln -s "$(command -v bash)" "$TMP/no-nix/bash"

cat > "$TMP/bin/just" <<'EOF'
#!/usr/bin/env bash
set -euo pipefail
if [[ "${1:-}" == _child && -n "${FAKE_JUST_NESTED_ARGS:-}" ]]; then
    printf '%s\0' "$@" > "$FAKE_JUST_NESTED_ARGS"
elif (($#)); then
    printf '%s\0' "$@" > "$FAKE_JUST_ARGS"
else
    : > "$FAKE_JUST_ARGS"
fi
if [[ "${1:-}" == _environment ]]; then
    [[ "${POLYMODEL_NIX_SHELL:-}" == 1 ]]
    [[ -d "${LDRAWDIR:-}" ]]
    [[ "${LD_LIBRARY_PATH:-}" == *"$FAKE_RUNTIME"* ]]
    [[ "${DISPLAY:-}" == :77 ]]
    [[ "${WAYLAND_DISPLAY:-}" == wayland-test ]]
fi
if [[ "${1:-}" == _nested ]]; then
    exec "$HELPER" _child 'nested value; $HOME'
fi
exit "${FAKE_JUST_EXIT:-0}"
EOF
chmod +x "$TMP/bin/just"
ln -s "$TMP/bin/just" "$TMP/no-nix/just"

cat > "$TMP/bin/nix" <<'EOF'
#!/usr/bin/env bash
set -euo pipefail
printf '%s\0' "$@" > "$FAKE_NIX_ARGS"
[[ ${1:-} == develop && -n ${2:-} && ${3:-} == --command ]] || exit 64
shift 3
export POLYMODEL_NIX_SHELL=1
export LDRAWDIR="$FAKE_LDRAWDIR"
export LD_LIBRARY_PATH="${LD_LIBRARY_PATH:-}:$FAKE_RUNTIME"
exec "$@"
EOF
chmod +x "$TMP/bin/nix"

run_outside() {
    : > "$TMP/nix.args"
    : > "$TMP/just.args"
    : > "$TMP/nested.args"
    env -u POLYMODEL_NIX_SHELL -u LDRAWDIR -u LD_LIBRARY_PATH \
        PATH="$TMP/bin:$PATH" \
        DISPLAY=:77 \
        WAYLAND_DISPLAY=wayland-test \
        FAKE_NIX_ARGS="$TMP/nix.args" \
        FAKE_JUST_ARGS="$TMP/just.args" \
        FAKE_JUST_NESTED_ARGS="$TMP/nested.args" \
        FAKE_JUST="$TMP/bin/just" \
        FAKE_LDRAWDIR="$TMP/ldraw" \
        FAKE_RUNTIME="$TMP/runtime" \
        HELPER="$HELPER" \
        "$HELPER" "$@"
}

run_outside _demo 'path with spaces; $(printf injected)' '--flag=value'
mapfile -d '' -t nix_args < "$TMP/nix.args"
[[ ${nix_args[0]} == develop && -n ${nix_args[1]} && ${nix_args[2]} == --command ]] || fail 'outside Nix dispatch prefix changed'
printf '%s\0' "$TMP/bin/just" _demo 'path with spaces; $(printf injected)' '--flag=value' > "$TMP/expected.args"
printf '%s\0' "${nix_args[@]:3}" > "$TMP/actual-command.args"
cmp "$TMP/expected.args" "$TMP/actual-command.args" || fail 'outside Nix command argv changed'
printf '%s\0' _demo 'path with spaces; $(printf injected)' '--flag=value' > "$TMP/expected.args"
cmp "$TMP/expected.args" "$TMP/just.args" || fail 'outside Just argv changed'

run_outside _environment

set +e
env -u POLYMODEL_NIX_SHELL -u LDRAWDIR -u LD_LIBRARY_PATH \
    PATH="$TMP/bin" \
    FAKE_NIX_ARGS="$TMP/nix.args" \
    FAKE_JUST_ARGS="$TMP/just.args" \
    FAKE_JUST="$TMP/bin/just" \
    FAKE_LDRAWDIR="$TMP/ldraw" \
    FAKE_RUNTIME="$TMP/runtime" \
    HELPER="$HELPER" \
    FAKE_JUST_EXIT=37 \
    "$HELPER" _exit-test
status=$?
set -e
[[ $status -eq 37 ]] || fail "exit status was $status, expected 37"

: > "$TMP/just.args"
env POLYMODEL_NIX_SHELL=1 \
    LDRAWDIR="$TMP/ldraw" \
    PATH="$TMP/bin" \
    FAKE_JUST_ARGS="$TMP/just.args" \
    "$HELPER" _direct 'inside value'
assert_args "$TMP/just.args" _direct 'inside value'

: > "$TMP/nix.args"
: > "$TMP/just.args"
run_outside _nested
assert_args "$TMP/just.args" _nested
assert_args "$TMP/nested.args" _child 'nested value; $HOME'
[[ $(wc -c < "$TMP/nix.args") -gt 0 ]] || fail 'nested public/private dispatch skipped outer shell entry'

set +e
env -u POLYMODEL_NIX_SHELL PATH="$TMP/no-nix" "$HELPER" _missing-nix 2>"$TMP/missing.stderr"
status=$?
set -e
[[ $status -eq 127 ]] || fail "missing nix status was $status, expected 127"
grep -F 'nix is required' "$TMP/missing.stderr" >/dev/null || fail 'missing nix diagnostic missing'

TEST_JUSTFILE="$TMP/justfile"
cat > "$TEST_JUSTFILE" <<EOF
public:
    @tools/in-dev-shell _private

_private:
    @printf 'private\\n'

test-deps: _private
    @printf 'deps\\n'
EOF
list=$(cd "$ROOT" && "$REAL_JUST" --list)
[[ "$list" != *'_fix'* && "$list" == *'fix'* ]] || fail 'private recipes leaked or public recipe disappeared'
private_list=$(cd "$TMP" && "$REAL_JUST" --justfile "$TEST_JUSTFILE" --list)
[[ "$private_list" == *'public'* && "$private_list" == *'test-deps'* && "$private_list" != *'_private'* ]] || fail 'private test recipe listing is wrong'

grep -F 'direnv allow "$workspace_path"' "$ROOT/justfile" >/dev/null || fail 'workspace-create does not allow the new workspace envrc'
grep -F 'direnv exec "$workspace_path" true' "$ROOT/justfile" >/dev/null || fail 'workspace-create does not verify the new workspace envrc'

printf 'PASS: in-dev-shell dispatch boundary\n'