#!/usr/bin/env bash
set -euo pipefail
umask 077

ROOT=$(CDPATH='' cd -- "$(dirname -- "$0")/.." && pwd)
BASE_ENV=${WNH_LOAD_BASE_ENV_FILE:-"$ROOT/.env.load"}
LABEL=${1:-"cycle-$(date -u +%Y%m%dT%H%M%SZ)"}
MODE=${2:-load}

if [[ ! "$LABEL" =~ ^[A-Za-z0-9._-]+$ ]]; then
  echo "Run label may contain only letters, numbers, dot, underscore, and dash." >&2
  exit 1
fi

case "$MODE" in
  load | resilience | both) ;;
  *)
    echo "Mode must be load, resilience, or both." >&2
    exit 1
    ;;
esac

WNH_LOAD_ENV_FILE="$BASE_ENV" "$ROOT/scripts/ensure-local-load-env.sh"

if [[ ! -f "$BASE_ENV" ]]; then
  echo "Missing base load environment: $BASE_ENV." >&2
  exit 1
fi

run_id="$(date -u +%Y%m%d%H%M%S)-$$"
safe_id=$(printf '%s' "$run_id" | tr -cd 'A-Za-z0-9')
project="who_need_help_load_$safe_id"
temporary_env=$(mktemp "${TMPDIR:-/tmp}/wnh-load-cycle.XXXXXX.env")
export WNH_LOAD_ENV_FILE=$temporary_env
export WNH_LOAD_TOOLS_IMAGE="who-need-help:load-tools-$safe_id"

cp "$BASE_ENV" "$temporary_env"
chmod 600 "$temporary_env"

set_env_value() {
  local name=$1
  local value=$2
  local replacement="$name=$value"

  if grep -q "^${name}=" "$temporary_env"; then
    sed -i "s|^${name}=.*|$replacement|" "$temporary_env"
  else
    printf '%s\n' "$replacement" >>"$temporary_env"
  fi
}

set_env_value LOAD_PROJECT "$project"
set_env_value COMPOSE_PROJECT_NAME "$project"
set_env_value TRAEFIK_PROJECT_CONSTRAINT "$project"
set_env_value TRAEFIK_DOCKER_NETWORK "${project}_ingress"
set_env_value APP_IMAGE "who-need-help:load-$safe_id"
set_env_value SOCKET_PROXY_IMAGE "who-need-help:socket-proxy-load-$safe_id"
set_env_value POSTGIS_IMAGE "who-need-help:postgis-load-$safe_id"

set -a
# shellcheck source=/dev/null
. "$temporary_env"
set +a

for name in APP_IMAGE SOCKET_PROXY_IMAGE POSTGIS_IMAGE; do
  if [[ -z "${!name:-}" ]]; then
    echo "$name is missing from the generated cycle environment." >&2
    exit 1
  fi
done

if [[ -n "$(docker ps -aq --filter "label=com.docker.compose.project=$project")" ]] ||
  [[ -n "$(docker network ls -q --filter "label=com.docker.compose.project=$project")" ]] ||
  [[ -n "$(docker volume ls -q --filter "label=com.docker.compose.project=$project")" ]]; then
  echo "Generated load-cycle project already owns Docker resources: $project." >&2
  exit 1
fi

started=0

cleanup() {
  local status=$?
  local cleanup_status=0
  trap - EXIT HUP INT TERM

  if [[ "$started" -eq 1 ]] ||
    [[ -n "$(docker ps -aq --filter "label=com.docker.compose.project=$project")" ]] ||
    [[ -n "$(docker network ls -q --filter "label=com.docker.compose.project=$project")" ]]; then
    "$ROOT/scripts/load-stack-stop.sh" >/dev/null 2>&1 || cleanup_status=1
  fi

  while IFS= read -r volume; do
    [[ -n "$volume" ]] || continue
    observed_project=$(docker volume inspect --format \
      '{{index .Labels "com.docker.compose.project"}}' "$volume")
    references=$(docker ps -aq --filter "volume=$volume")

    if [[ "$observed_project" != "$project" ]] || [[ -n "$references" ]]; then
      echo "Refusing unexpected or referenced load-cycle volume: $volume" >&2
      cleanup_status=1
      continue
    fi

    docker volume rm "$volume" >/dev/null || cleanup_status=1
  done < <(docker volume ls -q --filter "label=com.docker.compose.project=$project")

  for image in "$APP_IMAGE" "$SOCKET_PROXY_IMAGE" "$POSTGIS_IMAGE" \
    "$WNH_LOAD_TOOLS_IMAGE"; do
    if image_id=$(docker image inspect --format '{{.Id}}' "$image" 2>/dev/null); then
      if [[ -n "$(docker ps -aq --filter "ancestor=$image_id")" ]]; then
        echo "Refusing referenced load-cycle image: $image" >&2
        cleanup_status=1
      else
        docker image rm "$image" >/dev/null || cleanup_status=1
      fi
    fi
  done

  rm -f "$temporary_env"

  if [[ -n "$(docker ps -aq --filter "label=com.docker.compose.project=$project")" ]] ||
    [[ -n "$(docker network ls -q --filter "label=com.docker.compose.project=$project")" ]] ||
    [[ -n "$(docker volume ls -q --filter "label=com.docker.compose.project=$project")" ]]; then
    echo "Load-cycle cleanup left project resources behind: $project." >&2
    cleanup_status=1
  fi

  if [[ "$status" -eq 0 && "$cleanup_status" -ne 0 ]]; then
    status=$cleanup_status
  fi

  exit "$status"
}

trap cleanup EXIT HUP INT TERM

"$ROOT/scripts/load-stack-up.sh"
started=1

case "$MODE" in
  load)
    "$ROOT/scripts/load-run.sh" "$LABEL"
    ;;
  resilience)
    "$ROOT/scripts/load-resilience-run.sh" "$LABEL"
    ;;
  both)
    "$ROOT/scripts/load-run.sh" "$LABEL-load"
    "$ROOT/scripts/load-resilience-run.sh" "$LABEL-resilience"
    ;;
esac

echo "Load cycle completed; its project resources will now be removed: $project"