#!/usr/bin/env bash
# GPS-Denied Onboard — pull Docker images from the parent-suite registry.
#
# Cycle-1 images:
#   * ${REGISTRY_HOST}/azaion/gps-denied-onboard-companion-tier1:<branch>-<arch>
#   * ${REGISTRY_HOST}/azaion/gps-denied-onboard-operator-orchestrator:<branch>-<arch>
#
# Cycle-2 (when docker/companion-jetson.Dockerfile lands):
#   * ${REGISTRY_HOST}/azaion/gps-denied-onboard:<branch>-<arch>  (airborne)
#
# Reads REGISTRY_HOST / REGISTRY_USER / REGISTRY_TOKEN from environment
# or .env at the project root. Supports remote execution via SSH when
# DEPLOY_HOST is set (delegates to the remote host's local docker pull).
#
# Usage:
#   scripts/pull-images.sh [--branch <branch>] [--arch <arch>]
#                          [--target dev|airborne|operator-workstation]
#                          [--verify] [--help]
#
# Defaults:
#   branch = main
#   arch   = arm        (Jetson + suite arm64 build agent)
#   target = operator-workstation
#
# Exit codes:
#   0  all images pulled (or already up-to-date)
#   64 missing prerequisite (REGISTRY_HOST, docker on PATH)
#   65 SSH unreachable when DEPLOY_HOST is set
#   66 registry login failed
#   67 image pull failed

set -euo pipefail

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

usage() {
    cat <<'EOF'
GPS-Denied Onboard — pull Docker images from the parent-suite registry.

Cycle-1 images:
  * ${REGISTRY_HOST}/azaion/gps-denied-onboard-companion-tier1:<branch>-<arch>
  * ${REGISTRY_HOST}/azaion/gps-denied-onboard-operator-orchestrator:<branch>-<arch>

Cycle-2 (when docker/companion-jetson.Dockerfile lands):
  * ${REGISTRY_HOST}/azaion/gps-denied-onboard:<branch>-<arch>  (airborne)

Reads REGISTRY_HOST / REGISTRY_USER / REGISTRY_TOKEN from environment
or .env at the project root. Supports remote execution via SSH when
DEPLOY_HOST is set (delegates to the remote host's local docker pull).

Usage:
  scripts/pull-images.sh [--branch <branch>] [--arch <arch>]
                         [--target dev|airborne|operator-workstation]
                         [--verify] [--help]

Defaults:
  branch = main
  arch   = arm        (Jetson + suite arm64 build agent)
  target = operator-workstation

Exit codes:
  0  all images pulled (or already up-to-date)
  64 missing prerequisite (REGISTRY_HOST, docker on PATH)
  65 SSH unreachable when DEPLOY_HOST is set
  66 registry login failed
  67 image pull failed
EOF
    exit 0
}

BRANCH="${BRANCH:-main}"
ARCH="${ARCH:-arm}"
TARGET="operator-workstation"
VERIFY=0

while [ $# -gt 0 ]; do
    case "$1" in
        --branch) BRANCH="$2"; shift 2 ;;
        --arch)   ARCH="$2"; shift 2 ;;
        --target) TARGET="$2"; shift 2 ;;
        --verify) VERIFY=1; shift ;;
        --help|-h) usage ;;
        *) echo "ERROR: unknown argument: $1" >&2; usage ;;
    esac
done

if [ -f "${REPO_ROOT}/.env" ]; then
    set -a
    # shellcheck disable=SC1091
    . "${REPO_ROOT}/.env"
    set +a
fi

if [ -z "${REGISTRY_HOST:-}" ]; then
    echo "ERROR: REGISTRY_HOST not set (e.g. git.azaion.com)" >&2
    echo "       Set in .env or export before invoking." >&2
    exit 64
fi

remote_exec=""
if [ -n "${DEPLOY_HOST:-}" ]; then
    if ! ssh -o BatchMode=yes -o ConnectTimeout=5 "${DEPLOY_HOST}" true 2>/dev/null; then
        echo "ERROR: cannot reach 'ssh ${DEPLOY_HOST}' non-interactively." >&2
        exit 65
    fi
    remote_exec="ssh ${DEPLOY_HOST}"
fi

case "${TARGET}" in
    dev)
        IMAGES=(
            "${REGISTRY_HOST}/azaion/gps-denied-onboard-companion-tier1:${BRANCH}-${ARCH}"
            "${REGISTRY_HOST}/azaion/gps-denied-onboard-operator-orchestrator:${BRANCH}-${ARCH}"
        )
        ;;
    airborne)
        IMAGES=(
            "${REGISTRY_HOST}/azaion/gps-denied-onboard:${BRANCH}-${ARCH}"
        )
        ;;
    operator-workstation)
        IMAGES=(
            "${REGISTRY_HOST}/azaion/gps-denied-onboard-operator-orchestrator:${BRANCH}-${ARCH}"
        )
        ;;
    *)
        echo "ERROR: invalid --target: ${TARGET}" >&2
        echo "       Must be one of: dev, airborne, operator-workstation" >&2
        exit 64
        ;;
esac

echo "[pull-images] registry: ${REGISTRY_HOST}"
echo "[pull-images] branch:   ${BRANCH}"
echo "[pull-images] arch:     ${ARCH}"
echo "[pull-images] target:   ${TARGET}"
if [ -n "${remote_exec}" ]; then
    echo "[pull-images] remote:   ${DEPLOY_HOST}"
fi

if [ -n "${REGISTRY_USER:-}" ] && [ -n "${REGISTRY_TOKEN:-}" ]; then
    echo "[pull-images] docker login → ${REGISTRY_HOST}"
    if ! echo "${REGISTRY_TOKEN}" \
        | ${remote_exec} docker login "${REGISTRY_HOST}" \
            --username "${REGISTRY_USER}" --password-stdin >/dev/null; then
        echo "ERROR: docker login failed against ${REGISTRY_HOST}" >&2
        exit 66
    fi
else
    echo "[pull-images] REGISTRY_USER / REGISTRY_TOKEN not set — assuming"
    echo "             the registry is reachable anonymously or the local"
    echo "             docker config is already authenticated."
fi

for image in "${IMAGES[@]}"; do
    echo "[pull-images] pulling ${image}"
    if ! ${remote_exec} docker pull "${image}"; then
        echo "ERROR: failed to pull ${image}" >&2
        exit 67
    fi
done

if [ "${VERIFY}" = "1" ]; then
    echo "[pull-images] verifying image digests + AZAION_REVISION env"
    for image in "${IMAGES[@]}"; do
        digest=$(${remote_exec} docker image inspect \
            --format '{{(index .RepoDigests 0)}}' "${image}" 2>/dev/null || echo "")
        revision=$(${remote_exec} docker image inspect \
            --format '{{range .Config.Env}}{{println .}}{{end}}' "${image}" 2>/dev/null \
            | grep '^AZAION_REVISION=' | head -n1 | cut -d= -f2 || echo "")
        echo "  ${image}"
        echo "    digest:   ${digest:-<missing>}"
        echo "    revision: ${revision:-<missing>}"
    done
fi

echo "[pull-images] OK"