#!/usr/bin/env bash
# compile-gate.sh — the generator's primary acceptance gate.
#
# Generates the selected tier's monorepo from regression/tierN/config.toml, then requires the
# generated package to `swift build` with ZERO errors. Pass/fail only: error
# counts are not a metric. Also diffs each module's skip report against the
# committed baseline in regression/tierN/ (JSON files only) so that new
# skips in supported categories fail loudly.
#
# Usage:
#   scripts/compile-gate.sh <tier|all> [--fresh]
#
#   <tier>   1..6 (tier1 = GLib+GObject ... tier6 = full stack), or 'all'
#            'all' is the full-stack tier-6 alias and only generates tier 6
#   --fresh  remove the selected tier's output directory before generating
#            (use when the generated file set shrinks and stale files would linger)
#
# Output goes to ${TMPDIR:-/tmp}/gobject-generator-gate/tier-N; a stable path so
# incremental swift builds stay fast between runs.


set -euo pipefail

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
GATE_ROOT="${TMPDIR:-/tmp}/gobject-generator-gate"

TIER_ARG="${1:-}"
FRESH=0
[[ "${2:-}" == "--fresh" ]] && FRESH=1

if [[ -z "$TIER_ARG" ]]; then
	echo "usage: $0 <tier|all> [--fresh]" >&2
	exit 2
fi

if [[ "$TIER_ARG" == "all" ]]; then
	TIERS=(6)
else
	TIERS=("$TIER_ARG")
fi

echo "==> Building generator"
swift build --package-path "$ROOT"
BIN="$(swift build --package-path "$ROOT" --show-bin-path)/generator"

FAILED=0

run_tier() {
	local tier="$1"
	local config="$ROOT/regression/tier${tier}/config.toml"
	local out="$GATE_ROOT/tier-${tier}"

	if [[ ! -f "$config" ]]; then
		echo "!! tier $tier: missing $config" >&2
		return 1
	fi

	if [[ "$FRESH" == 1 ]]; then
		rm -rf "$out"
	fi
	mkdir -p "$out"

	echo "==> Tier $tier: generating into $out"
	if ! "$BIN" --monorepo-config "$config" --output "$out" --skip-report --format-config "$ROOT/.swift-format" >"$out/generate.log" 2>&1; then
		echo "!! tier $tier: GENERATION FAILED (see $out/generate.log)" >&2
		tail -n 20 "$out/generate.log" >&2
		return 1
	fi

	echo "==> Tier $tier: swift build"
	if ! swift build --package-path "$out" >"$out/build.log" 2>&1; then
		echo "!! tier $tier: BUILD FAILED (see $out/build.log)" >&2
		grep -m 10 'error:' "$out/build.log" >&2 || tail -n 20 "$out/build.log" >&2
		return 1
	fi

	echo "==> Tier $tier: swift format lint"
	if ! swift format lint --strict --configuration "$ROOT/.swift-format" --recursive --parallel "$out/Sources" >"$out/lint.log" 2>&1; then
		echo "!! tier $tier: LINT FAILED (see $out/lint.log)" >&2
		head -n 40 "$out/lint.log" >&2
		return 1
	fi

	local baseline="$ROOT/regression/tier${tier}"
	if [[ -d "$baseline" ]]; then
		echo "==> Tier $tier: diffing skip reports against $baseline"
		local tmp_baseline
		tmp_baseline="$(mktemp -d)"
		cp "$baseline"/*.json "$tmp_baseline/" 2>/dev/null || true
		if ! diff -ru "$tmp_baseline" "$out/skip-reports" >"$out/skip-diff.log" 2>&1; then
			rm -rf "$tmp_baseline"
			echo "!! tier $tier: SKIP REPORT CHANGED (see $out/skip-diff.log)" >&2
			head -n 40 "$out/skip-diff.log" >&2
			echo "   If the change is intentional (coverage grew), refresh the baseline:" >&2
			echo "   cp -r $out/skip-reports/*.json $baseline/" >&2
			return 1
		fi
		rm -rf "$tmp_baseline"
	else
		echo "==> Tier $tier: no skip baseline at $baseline (skipping diff)"
	fi

	echo "==> Tier $tier: PASS"
}

for tier in "${TIERS[@]}"; do
	if ! run_tier "$tier"; then
		FAILED=1
	fi
done

exit "$FAILED"