#!/usr/bin/env bash
# Apply candidate image digests from a promotion receipt to test|main.
# Retags local images and writes configs/.env.<env>.images for pinned compose.
#
# Usage:
#   ./scripts/candidate-images-apply.sh <test|main> [--commit SHA]
set -euo pipefail

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
cd "${ROOT}"

ENV_NAME="${1:-}"
shift || true
COMMIT=""

while [[ $# -gt 0 ]]; do
  case "$1" in
    --commit) COMMIT="${2:-}"; shift 2 ;;
    -h|--help)
      sed -n '2,8p' "$0" | sed 's/^# \{0,1\}//'
      exit 0
      ;;
    *) echo "unknown arg: $1" >&2; exit 1 ;;
  esac
done

case "${ENV_NAME}" in
  test|main) ;;
  *) echo "usage: $0 <test|main> [--commit SHA]" >&2; exit 1 ;;
esac

if [[ -z "${COMMIT}" ]]; then
  if [[ "${ENV_NAME}" == "test" ]]; then
    COMMIT="$(git rev-parse dev)"
  else
    COMMIT="$(git rev-parse test)"
  fi
fi
COMMIT="$(git rev-parse --verify "${COMMIT}^{commit}" 2>/dev/null || echo "${COMMIT}")"
COMMIT="$(echo "${COMMIT}" | tr 'A-F' 'a-f')"

RECEIPT_DIR="${ROOT}/.doc/test-reports/assets/promotion-receipts"
RECEIPT=""
if [[ -f "${RECEIPT_DIR}/${COMMIT}.json" ]]; then
  RECEIPT="${RECEIPT_DIR}/${COMMIT}.json"
else
  shopt -s nullglob
  for f in "${RECEIPT_DIR}"/*.json; do
    base="$(basename "${f}" .json)"
    [[ "${base}" == *.waiver ]] && continue
    [[ "${base}" == *.images ]] && continue
    if [[ "${COMMIT}" == "${base}"* || "${base}" == "${COMMIT}"* ]]; then
      RECEIPT="${f}"
      break
    fi
  done
fi

if [[ -z "${RECEIPT}" || ! -f "${RECEIPT}" ]]; then
  echo "error: no promotion receipt for ${COMMIT}" >&2
  exit 1
fi

export RECEIPT ENV_NAME ROOT
python3 <<'PY'
import json, os, subprocess, sys

receipt_path = os.environ["RECEIPT"]
env_name = os.environ["ENV_NAME"]
root = os.environ["ROOT"]

with open(receipt_path, encoding="utf-8") as f:
    receipt = json.load(f)

verdict = receipt.get("verdict")
if verdict != "pass":
    # allow apply when digests present on a pass-only path; still warn
    print(f"warning: receipt verdict={verdict!r} (expected pass)", file=sys.stderr)

digests = receipt.get("image_digests") or {}
app_d = digests.get("app") or ""
events_d = digests.get("events") or ""
pi_d = digests.get("pi-agent") or ""
missing = [k for k, v in (("app", app_d), ("events", events_d), ("pi-agent", pi_d)) if not v]
if missing:
    print(f"error: receipt missing image_digests: {', '.join(missing)}", file=sys.stderr)
    sys.exit(1)

def resolve_local_id(ref: str) -> str:
    # ref may be sha256:ID, name@sha256:..., or full image id
    candidates = [ref]
    if ref.startswith("sha256:"):
        candidates.append(ref)
    elif "@sha256:" in ref:
        candidates.append(ref.split("@", 1)[1])
    for c in candidates:
        try:
            out = subprocess.check_output(
                ["docker", "image", "inspect", "--format", "{{.Id}}", c],
                stderr=subprocess.DEVNULL,
                text=True,
            ).strip()
            if out:
                return out
        except subprocess.CalledProcessError:
            continue
    print(f"error: image not found locally for digest/ref: {ref}", file=sys.stderr)
    print("hint: run scripts/candidate-images-build.sh for this commit first", file=sys.stderr)
    sys.exit(1)

app_id = resolve_local_id(app_d)
events_id = resolve_local_id(events_d)
pi_id = resolve_local_id(pi_d)

tags = {
    "app": f"shuimu-agent-app:{env_name}",
    "events": f"shuimu-agent-events:{env_name}",
    "pi-agent": f"shuimu-pi-agent:{env_name}",
}
for img_id, tag in ((app_id, tags["app"]), (events_id, tags["events"]), (pi_id, tags["pi-agent"])):
    subprocess.check_call(["docker", "tag", img_id, tag])
    got = subprocess.check_output(
        ["docker", "image", "inspect", "--format", "{{.Id}}", tag], text=True
    ).strip()
    if got != img_id:
        print(f"error: retag mismatch for {tag}: want {img_id} got {got}", file=sys.stderr)
        sys.exit(1)
    print(f"tagged {tag} -> {got}")

# Pin compose to retagged tags (same IDs as receipt).
env_path = os.path.join(root, f"configs/.env.{env_name}.images")
lines = [
    f"# generated by candidate-images-apply.sh from {os.path.basename(receipt_path)}",
    f"APP_IMAGE={tags['app']}",
    f"EVENTS_IMAGE={tags['events']}",
    f"PI_AGENT_IMAGE={tags['pi-agent']}",
    f"PINNED_IMAGE_MODE=1",
    f"PINNED_COMMIT={receipt.get('commit') or ''}",
    f"PINNED_APP_DIGEST={app_d}",
    f"PINNED_EVENTS_DIGEST={events_d}",
    f"PINNED_PI_AGENT_DIGEST={pi_d}",
    "",
]
with open(env_path, "w", encoding="utf-8") as f:
    f.write("\n".join(lines))
print(f"wrote {env_path}")
PY