#!/usr/bin/env bash
# ci/gate.sh — the merge-gate decision. Runs every stage in order and applies the
# R-TEST-03 rule: a merge is allowed only when the touched-requirement subset is
# GREEN. Honestly distinguishes three outcomes per stage:
#   pass (0)  green
#   fail (1)  BLOCKS the merge
#   skip (3)  not run (cluster-gated stage w/ no cluster, or unwired seam) —
#             NOT counted as green (HARD RULE 4: don't fake green)
#
# Phase 0 policy (no cluster): L0/L1 stages (lint, schema, kyverno, L1 render)
# MUST be green. L2/L3 SKIP. If the touched subset needs L2/L3 and no cluster is
# available, the gate reports those requirements UNVERIFIED and — unless
# REQUIRE_CLUSTER_TESTS=true — does not hard-block Phase-0 bootstrap work, while
# making the gap loud. Set REQUIRE_CLUSTER_TESTS=true (Phase 1+) to make any
# skipped, cluster-needing touched requirement a hard block.
set -uo pipefail   # NOTE: no -e; we want to run all stages and aggregate.
CI_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck disable=SC1091
source "${CI_DIR}/lib.sh"
set +e   # lib.sh enables -e; the gate must run ALL stages and aggregate, not abort.

: "${REQUIRE_CLUSTER_TESTS:=false}"

declare -A OUTCOME
run_stage() {
  local name="$1"; shift
  log "==== stage: ${name} ===="
  "$@"
  local rc=$?
  case "$rc" in
    0) OUTCOME[$name]="pass"; ok  "stage ${name}: pass" ;;
    3) OUTCOME[$name]="skip"; skip "stage ${name}: SKIPPED (not run)" ;;
    *) OUTCOME[$name]="fail"; err "stage ${name}: FAIL" ;;
  esac
}

summary "## Merge gate (R-TEST-03)"
summary ""

run_stage spec-immutability "${CI_DIR}/spec-immutability.sh"
run_stage lint        "${CI_DIR}/lint.sh"
run_stage l0          "${CI_DIR}/l0.sh"
run_stage l1          "${CI_DIR}/l1.sh"
run_stage conformance "${CI_DIR}/conformance.sh"

echo >&2
log "==== gate decision ===="
BLOCK=0

# spec-immutability (R-TEST-06): a FAIL always blocks (the spec was modified/drifted).
# A skip means the spec repo wasn't available to verify — surfaced, not green.
case "${OUTCOME[spec-immutability]}" in
  fail) err  "spec-immutability: FAILED -> blocks merge (R-TEST-06)"; BLOCK=1 ;;
  skip) warn "spec-immutability: skipped (spec repo unavailable) — not verified" ;;
  pass) ok   "spec-immutability: green" ;;
esac

# L0/L1 stages: any failure blocks. A SKIP here means a seam is unwired — in
# Phase 0 that is tolerated (placeholders), but surfaced.
for s in lint l0 l1; do
  case "${OUTCOME[$s]}" in
    fail) err  "${s}: FAILED -> blocks merge"; BLOCK=1 ;;
    skip) warn "${s}: skipped (unwired seam / missing tool) — not green" ;;
    pass) ok   "${s}: green" ;;
  esac
done

# L2/L3 conformance: cluster-gated.
case "${OUTCOME[conformance]}" in
  fail)
    err "conformance (L2/L3): FAILED -> blocks merge"; BLOCK=1 ;;
  pass)
    ok  "conformance (L2/L3): green" ;;
  skip)
    if cluster_available; then
      err "conformance: skipped despite CLUSTER_AVAILABLE=true -> blocks merge"; BLOCK=1
    else
      mapfile -t reqs < <("${CI_DIR}/touched-requirements.sh" || true)
      if [ "${#reqs[@]}" -gt 0 ]; then
        warn "conformance L2/L3 UNVERIFIED for touched requirements: ${reqs[*]}"
        warn "  (no cluster — Phase 0). These are NOT certified green."
        summary "- **UNVERIFIED (no cluster):** ${reqs[*]}"
        if [ "$REQUIRE_CLUSTER_TESTS" = "true" ]; then
          err "REQUIRE_CLUSTER_TESTS=true and cluster-needing requirements are unverified -> blocks merge"
          BLOCK=1
        fi
      else
        skip "conformance L2/L3 skipped; no cluster-needing requirements touched"
      fi
    fi ;;
esac

echo >&2
if [ "$BLOCK" -eq 0 ]; then
  ok "MERGE GATE: PASS (touched-requirement subset green for the layers that can run)"
  summary ""
  summary "**Result: PASS** — L0/L1 green. L2/L3 status per cluster availability above."
  exit 0
else
  err "MERGE GATE: BLOCKED"
  summary ""
  summary "**Result: BLOCKED** — see failures above."
  exit 1
fi