#!/usr/bin/env bash
# Tier 2 gate: types, build, content contracts, dependency audit, tokens.
# Invoked by .husky/pre-push, and safe to run by hand at any time.
#
# Parallel-safe: takes a lock in the SHARED git dir, so ten agents pushing from
# ten worktrees queue instead of running ten concurrent Astro builds and
# thrashing the machine. Waiters block; they do not fail.
set -euo pipefail

root=$(git rev-parse --show-toplevel)
cd "$root"

# --git-common-dir resolves to the ONE shared .git across all worktrees, which
# is exactly the scope we want the lock to cover.
common=$(git rev-parse --git-common-dir)
lock="$common/af-gate.lock"

exec 9>"$lock"
if ! flock -n 9; then
  echo "gate: another worktree is running the gate — waiting for it…"
  flock 9
fi

started=$(date +%s)
step() { printf '\n\033[1m▸ %s\033[0m\n' "$1"; }

# Fail loudly rather than passing vacuously when the toolchain is not installed.
if [ ! -d node_modules ]; then
  echo "gate: node_modules missing — run 'pnpm install --frozen-lockfile' first" >&2
  exit 1
fi

# This project is pnpm-only. An agent that runs `npm install` out of habit gets
# a second, divergent dependency tree and a lockfile nobody reads — the same
# class of failure that cost two sessions during phase 0. Catch it here.
if [ -f package-lock.json ] || [ -f yarn.lock ] || [ -f bun.lock ] || [ -f bun.lockb ]; then
  echo "gate: a non-pnpm lockfile is present. This project uses pnpm only." >&2
  echo "      Delete it, then run 'pnpm install --frozen-lockfile'." >&2
  exit 1
fi

step "types"
pnpm exec astro check

step "build"
# `astro build` exits 0 even when vite fails to resolve an asset: the cutover
# left a stale `@import` in a moved stylesheet and every gate stayed green for
# it. Treat a logged error as a failed build.
build_log=$(mktemp)
if ! pnpm run build 2>&1 | tee "$build_log"; then
  rm -f "$build_log"
  exit 1
fi
if grep -q '\[ERROR\]' "$build_log"; then
  echo "gate: astro build logged an error and still exited 0. See above." >&2
  rm -f "$build_log"
  exit 1
fi
rm -f "$build_log"

step "content contracts"
pnpm run verify

# The assertion count is the thing agents are most tempted to "fix" downward.
# Compare against origin/main and refuse a silent reduction.
step "assertion coverage"
# Task 19 restored the 42 legacy facts and added ten output snapshots: 84 is the
# floor, in addition to whatever origin/main currently requires.
#
# A removal is allowed only by writing a reason into the ledger. The gate counts
# its entries and lowers the bar by exactly that many, so the bar cannot move
# without a visible diff explaining why. Deleting an entry to buy headroom is
# the same offence as deleting the assertion was.
ledger=.agents/context/assertion-removals.md
current=$(grep -c 'throw new Error' scripts/verify.mjs)
allowed=$(grep -c '^## ' "$ledger" 2>/dev/null || echo 0)
baseline=$(git show origin/main:scripts/verify.mjs 2>/dev/null | grep -c 'throw new Error' || echo 0)
if [ "$baseline" -lt 84 ]; then baseline=84; fi
baseline=$((baseline - allowed))
if [ "$current" -lt "$baseline" ]; then
  echo "gate: verify.mjs coverage fell from $baseline to $current assertions." >&2
  echo "      Only verification-engineer may reduce it, with a reason per removal." >&2
  echo "      See .agents/context/verification.md" >&2
  exit 1
fi
echo "  $current assertions (baseline $baseline)"

step "runtime dependency audit"
node scripts/audit-ui.mjs

step "design tokens"
node .agents/scripts/check-tokens.mjs

printf '\n\033[32mgate passed\033[0m in %ss\n' "$(( $(date +%s) - started ))"
