#!/usr/bin/env sh
# Copy-by-digest зеркало базовых образов в Gitea Container Registry (без rebuild).
# Требует: docker login в REGISTRY host, docker buildx.
# REGISTRY=git.shx.one/<owner>  (без суффикса /evofw-buildcache)
#
# Источник library-образов — Docker Hub (docker.io).
# Если тег уже есть в Gitea — skip (без повторного pull).
# Копируем только linux/amd64 — bake platforms совпадает.
# Шаг CD не должен падать: неуспешный copy оставляет bake на Docker Hub FROM.
set -eu
REGISTRY="${REGISTRY:?REGISTRY required (git.shx.one/<owner>)}"
CACHE_REPO="${REGISTRY}/evofw-buildcache"
ENV_FILE="${MIRROR_ENV_FILE:-}"
PLATFORM="${MIRROR_PLATFORM:-linux/amd64}"
RETRIES="${MIRROR_RETRIES:-4}"

tmp="$(mktemp)"
cleanup() { rm -f "$tmp"; }
trap cleanup EXIT

dest_exists() {
  docker buildx imagetools inspect "$1" >/dev/null 2>&1
}

copy_retry() {
  src="$1"
  dest="$2"
  n=0
  while [ "$n" -lt "$RETRIES" ]; do
    n=$((n + 1))
    if docker buildx imagetools create --platform "$PLATFORM" --tag "$dest" "$src"; then
      return 0
    fi
    delay=$((n * 25))
    echo "mirror retry ${n}/${RETRIES}, sleep ${delay}s: ${dest}"
    sleep "$delay"
  done
  return 1
}

mirror() {
  src="$1"
  tag="$2"
  var="$3"
  dest="${CACHE_REPO}:${tag}"
  if dest_exists "$dest"; then
    echo "skip (already in registry): ${dest}"
    printf '%s=%s\n' "$var" "$dest" >>"$tmp"
    return 0
  fi
  echo "mirror ${src} -> ${dest} (${PLATFORM})"
  if copy_retry "$src" "$dest"; then
    printf '%s=%s\n' "$var" "$dest" >>"$tmp"
    return 0
  fi
  echo "warn: ${dest} not mirrored — bake uses Docker Hub FROM for ${var}"
  return 0
}

mirror "docker.io/library/node:22-alpine" "base-node-22-alpine" BASE_NODE

echo "----- mirrored BASE_* -----"
cat "$tmp"
if [ -n "$ENV_FILE" ]; then
  env_dir="$(dirname "$ENV_FILE")"
  if [ -d "$env_dir" ]; then
    cp "$tmp" "$ENV_FILE"
    echo "wrote ${ENV_FILE}"
  else
    echo "warn: MIRROR_ENV_FILE dir missing (${env_dir}) — skip write"
  fi
fi