#!/usr/bin/env bash
#
# clawmates rolling deploy — polls the fleet registry for :latest of the three
# prod images (broker, server, frontend). On drift, pulls the new image, retags
# it under the un-prefixed name the running compose file uses, and rolls the
# affected services with `docker compose up -d`.
#
# Install:
#   sudo install -m 0755 clawmates-deploy.sh /usr/local/bin/clawmates-deploy.sh
#   sudo install -m 0644 clawmates-deploy.service /etc/systemd/system/
#   sudo install -m 0644 clawmates-deploy.timer   /etc/systemd/system/
#   sudo systemctl daemon-reload
#   sudo systemctl enable --now clawmates-deploy.timer
#
# Verify:
#   systemctl list-timers clawmates-deploy.timer
#   tail -f /var/log/clawmates-deploy.log
#
# The retag step (registry/clawmates/<svc>:latest → clawmates/<svc>:latest)
# keeps the current /root/clawmates/docker-compose.yml working unchanged until
# we're ready to migrate the compose file to registry-prefixed image names.

set -euo pipefail

REGISTRY="${REGISTRY:-100.94.185.103:5000}"
NAMESPACE="${NAMESPACE:-clawmates}"
COMPOSE_DIR="${COMPOSE_DIR:-/root/clawmates}"
LOG="${LOG:-/var/log/clawmates-deploy.log}"
SERVICES=(broker server frontend)

log() { printf '%s %s\n' "$(date -Iseconds)" "$*" | tee -a "$LOG" >/dev/null; }

changed=()
for svc in "${SERVICES[@]}"; do
  ref="${REGISTRY}/${NAMESPACE}/${svc}:latest"
  local_ref="${NAMESPACE}/${svc}:latest"

  if ! docker pull -q "$ref" >/dev/null 2>&1; then
    log "pull failed: $ref"
    continue
  fi

  # Keep the un-prefixed tag pointing at the fresh image so the compose file
  # (which references clawmates/<svc>:latest) picks up the new image on `up`.
  docker tag "$ref" "$local_ref"

  # True drift check: is the running container's image ID the same as what
  # `clawmates/<svc>:latest` now points to? Comparing pre/post pull digests
  # only catches new pulls — if a previous roll failed after the retag but
  # before `up`, the tag was updated but the container wasn't. This catches
  # that case on the next run.
  target=$(docker inspect --format '{{.Id}}' "$local_ref")
  cid=$(docker ps -q --filter "name=clawmates_${svc}_1")
  running=""
  [ -n "$cid" ] && running=$(docker inspect --format '{{.Image}}' "$cid")

  if [[ "$running" != "$target" ]]; then
    log "$svc drift: running=${running:-<none>} target=$target"
    changed+=("$svc")
  fi
done

if [[ ${#changed[@]} -eq 0 ]]; then
  exit 0
fi

log "rolling: ${changed[*]}"
cd "$COMPOSE_DIR"
# Prefer `docker compose` (v2 plugin); fall back to legacy `docker-compose`
# (v1). GW-04 currently ships v1 only; this makes the script portable if we
# ever move the stack to a host with the plugin.
if docker compose version >/dev/null 2>&1; then
  docker compose up -d "${changed[@]}"
else
  docker-compose up -d "${changed[@]}"
fi
log "roll complete: ${changed[*]}"