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

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

env_file="${repo_root}/.env.devprod"
compose_file=""
output_mode="json"

usage() {
  cat <<USAGE
Usage: ./scripts/topology/discover-cloud-topology.sh [options]

Detect running cloud topology and print install profile recommendation.

Options:
  --repo-root <path>       Repository root (default: auto)
  --env-file <path>        Env file to inspect (default: .env.devprod)
  --compose-file <path>    Compose file override
  --json                   JSON output (default)
  --text                   Human-readable output
  -h, --help               Show this help
USAGE
}

json_escape() {
  local input="${1:-}"
  input="${input//\\/\\\\}"
  input="${input//\"/\\\"}"
  input="${input//$'\n'/\\n}"
  input="${input//$'\r'/}"
  input="${input//$'\t'/\\t}"
  printf '%s' "${input}"
}

bool_json() {
  if [[ "${1:-0}" == "1" ]]; then
    printf 'true'
  else
    printf 'false'
  fi
}

run_timeout_cmd() {
  if command -v timeout >/dev/null 2>&1; then
    timeout 20 "$@"
  else
    "$@"
  fi
}

host_occ_runner() {
  if [[ -z "${host_occ_path:-}" || ! -f "${host_occ_path:-}" ]]; then
    return 1
  fi
  if [[ -z "$(command -v php || true)" ]]; then
    return 1
  fi
  if [[ "${EUID:-$(id -u)}" -eq 0 ]]; then
    if command -v sudo >/dev/null 2>&1; then
      run_timeout_cmd sudo -u www-data php "${host_occ_path}" "$@"
      return $?
    fi
    if command -v runuser >/dev/null 2>&1; then
      run_timeout_cmd runuser -u www-data -- php "${host_occ_path}" "$@"
      return $?
    fi
  fi
  run_timeout_cmd php "${host_occ_path}" "$@"
}

read_kv() {
  local key="$1"
  local file="$2"
  local line
  line="$(grep -m1 -E "^${key}=" "${file}" 2>/dev/null || true)"
  if [[ -z "${line}" ]]; then
    return 1
  fi
  printf '%s' "${line#*=}"
}

while [[ $# -gt 0 ]]; do
  case "$1" in
    --repo-root)
      repo_root="${2:-}"
      shift 2
      ;;
    --repo-root=*)
      repo_root="${1#*=}"
      shift
      ;;
    --env-file)
      env_file="${2:-}"
      shift 2
      ;;
    --env-file=*)
      env_file="${1#*=}"
      shift
      ;;
    --compose-file)
      compose_file="${2:-}"
      shift 2
      ;;
    --compose-file=*)
      compose_file="${1#*=}"
      shift
      ;;
    --json)
      output_mode="json"
      shift
      ;;
    --text)
      output_mode="text"
      shift
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      echo "Unknown option: $1"
      usage
      exit 1
      ;;
  esac
done

if [[ "${repo_root}" != /* ]]; then
  repo_root="$(cd "${repo_root}" 2>/dev/null && pwd)"
fi

if [[ "${env_file}" != /* ]]; then
  env_file="${repo_root}/${env_file}"
fi

if [[ -z "${compose_file}" ]]; then
  if [[ -f "${repo_root}/docker-compose.devprod.nossl.yml" ]]; then
    compose_file="${repo_root}/docker-compose.devprod.nossl.yml"
  elif [[ -f "${repo_root}/docker-compose.devprod.yml" ]]; then
    compose_file="${repo_root}/docker-compose.devprod.yml"
  else
    compose_file="${repo_root}/docker-compose.devprod.nossl.yml"
  fi
fi

if [[ "${compose_file}" != /* ]]; then
  compose_file="${repo_root}/${compose_file}"
fi

has_docker_cli="0"
has_compose_plugin="0"
docker_daemon_reachable="0"
env_exists="0"
compose_exists="0"
compose_config_ok="0"
compose_has_app_service="0"
compose_occ_ok="0"
compose_services_count="0"
host_occ_exists="0"
host_occ_status_ok="0"
host_occ_path=""

if command -v docker >/dev/null 2>&1; then
  has_docker_cli="1"
  if docker compose version >/dev/null 2>&1; then
    has_compose_plugin="1"
  fi
  if docker info >/dev/null 2>&1; then
    docker_daemon_reachable="1"
  fi
fi

if [[ -f "${env_file}" ]]; then
  env_exists="1"
fi

if [[ -f "${compose_file}" ]]; then
  compose_exists="1"
fi

services_list=""
if [[ "${has_compose_plugin}" == "1" && "${compose_exists}" == "1" && "${env_exists}" == "1" ]]; then
  if services_list="$(docker compose -f "${compose_file}" --env-file "${env_file}" config --services 2>/dev/null || true)"; then
    if [[ -n "${services_list}" ]]; then
      compose_config_ok="1"
      compose_services_count="$(printf '%s\n' "${services_list}" | sed '/^$/d' | wc -l | awk '{print $1}')"
      if printf '%s\n' "${services_list}" | grep -q '^app$'; then
        compose_has_app_service="1"
      fi
    fi
  fi
fi

if [[ "${compose_has_app_service}" == "1" && "${docker_daemon_reachable}" == "1" ]]; then
  if docker compose -f "${compose_file}" --env-file "${env_file}" exec -T app php occ status >/dev/null 2>&1; then
    compose_occ_ok="1"
  fi
fi

occ_candidates=(
  "/var/www/nextcloud/occ"
  "/var/www/html/nextcloud/occ"
  "/var/www/html/occ"
  "/srv/www/nextcloud/occ"
  "/var/lib/nextcloud/occ"
)

for candidate in "${occ_candidates[@]}"; do
  if [[ -f "${candidate}" ]]; then
    host_occ_exists="1"
    host_occ_path="${candidate}"
    break
  fi
done

if [[ "${host_occ_exists}" == "1" && -n "${host_occ_path}" && -x "$(command -v php || true)" ]]; then
  if host_occ_runner status >/dev/null 2>&1; then
    host_occ_status_ok="1"
  fi
fi

topology_id="unknown"
topology_confidence="low"
topology_reason="No known Nextcloud runtime detected."
recommended_profile="manual"
recommended_command=""
recommended_notes=()

if [[ "${compose_occ_ok}" == "1" ]]; then
  topology_id="repo_docker_devprod"
  topology_confidence="high"
  topology_reason="Detected Docker Compose stack with working Nextcloud OCC in app container."
  recommended_profile="repo-devprod-bootstrap"
  recommended_command="./scripts/topology/apply-topology-profile.sh --profile repo-devprod-bootstrap --repo-root \"${repo_root}\" --env-file \"${env_file}\" --compose-file \"${compose_file}\""
  recommended_notes+=("Best path for this topology: run recreate + finish setup using repository scripts.")
elif [[ "${compose_config_ok}" == "1" && "${has_docker_cli}" == "1" ]]; then
  topology_id="docker_compose_generic"
  topology_confidence="medium"
  topology_reason="Detected Docker Compose config, but Nextcloud OCC in app container is not currently healthy."
  recommended_profile="repo-devprod-bootstrap"
  recommended_command="./scripts/topology/apply-topology-profile.sh --profile repo-devprod-bootstrap --repo-root \"${repo_root}\" --env-file \"${env_file}\" --compose-file \"${compose_file}\""
  recommended_notes+=("Run profile apply to attempt full container recreate and repair.")
elif [[ "${host_occ_exists}" == "1" ]]; then
  if [[ "${host_occ_status_ok}" == "1" && "${docker_daemon_reachable}" == "1" ]]; then
    topology_id="host_nextcloud_plus_docker"
    topology_confidence="high"
    topology_reason="Detected host-level Nextcloud OCC with working status check and a reachable Docker daemon."
    recommended_notes+=("This is the primary existing-instance adoption target: keep host Nextcloud in place and add NuQloud sidecars around it.")
    recommended_notes+=("The host-hybrid installer now handles bootstrap, app wiring, and lifecycle helpers for this topology.")
    recommended_notes+=("If Talk/Office/notify_push are already configured on the host, prefer reusing them instead of replacing them.")
  else
    topology_id="host_nextcloud"
    topology_confidence="medium"
    topology_reason="Detected host-level Nextcloud OCC path outside repository Docker stack."
  fi
  recommended_profile="host-nextcloud-hybrid"
  recommended_command="./scripts/install-host-nextcloud-hybrid.sh --repo-root \"${repo_root}\" --occ-path \"${host_occ_path}\""
  recommended_notes+=("Host-level integration now has a dedicated installer plus restart/stop/update wrappers.")
fi

if [[ "${output_mode}" == "text" ]]; then
  echo "Topology ID: ${topology_id}"
  echo "Confidence: ${topology_confidence}"
  echo "Reason: ${topology_reason}"
  echo
  echo "Capabilities:"
  echo "  docker_cli: ${has_docker_cli}"
  echo "  docker_compose_plugin: ${has_compose_plugin}"
  echo "  docker_daemon_reachable: ${docker_daemon_reachable}"
  echo "  env_file_exists: ${env_exists}"
  echo "  compose_file_exists: ${compose_exists}"
  echo "  compose_config_ok: ${compose_config_ok}"
  echo "  compose_has_app_service: ${compose_has_app_service}"
  echo "  compose_occ_ok: ${compose_occ_ok}"
  echo "  host_occ_exists: ${host_occ_exists}"
  echo "  host_occ_status_ok: ${host_occ_status_ok}"
  echo
  echo "Recommendation:"
  echo "  profile: ${recommended_profile}"
  if [[ -n "${recommended_command}" ]]; then
    echo "  command: ${recommended_command}"
  fi
  if [[ "${#recommended_notes[@]}" -gt 0 ]]; then
    echo "  notes:"
    for note in "${recommended_notes[@]}"; do
      echo "    - ${note}"
    done
  fi
  exit 0
fi

notes_json=""
if [[ "${#recommended_notes[@]}" -gt 0 ]]; then
  note_first="1"
  for note in "${recommended_notes[@]}"; do
    if [[ "${note_first}" == "1" ]]; then
      notes_json="${notes_json}\"$(json_escape "${note}")\""
      note_first="0"
    else
      notes_json="${notes_json},\"$(json_escape "${note}")\""
    fi
  done
fi

generated_at="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
printf '{\n'
printf '  "ok": true,\n'
printf '  "generatedAt": "%s",\n' "$(json_escape "${generated_at}")"
printf '  "topology": {\n'
printf '    "id": "%s",\n' "$(json_escape "${topology_id}")"
printf '    "confidence": "%s",\n' "$(json_escape "${topology_confidence}")"
printf '    "reason": "%s"\n' "$(json_escape "${topology_reason}")"
printf '  },\n'
printf '  "paths": {\n'
printf '    "repoRoot": "%s",\n' "$(json_escape "${repo_root}")"
printf '    "envFile": "%s",\n' "$(json_escape "${env_file}")"
printf '    "composeFile": "%s",\n' "$(json_escape "${compose_file}")"
printf '    "hostOccPath": "%s"\n' "$(json_escape "${host_occ_path}")"
printf '  },\n'
printf '  "capabilities": {\n'
printf '    "dockerCli": %s,\n' "$(bool_json "${has_docker_cli}")"
printf '    "dockerComposePlugin": %s,\n' "$(bool_json "${has_compose_plugin}")"
printf '    "dockerDaemonReachable": %s,\n' "$(bool_json "${docker_daemon_reachable}")"
printf '    "envFileExists": %s,\n' "$(bool_json "${env_exists}")"
printf '    "composeFileExists": %s,\n' "$(bool_json "${compose_exists}")"
printf '    "composeConfigOk": %s,\n' "$(bool_json "${compose_config_ok}")"
printf '    "composeHasAppService": %s,\n' "$(bool_json "${compose_has_app_service}")"
printf '    "composeOccOk": %s,\n' "$(bool_json "${compose_occ_ok}")"
printf '    "composeServicesCount": %s,\n' "$(json_escape "${compose_services_count}")"
printf '    "hostOccExists": %s,\n' "$(bool_json "${host_occ_exists}")"
printf '    "hostOccStatusOk": %s\n' "$(bool_json "${host_occ_status_ok}")"
printf '  },\n'
printf '  "recommendation": {\n'
printf '    "profile": "%s",\n' "$(json_escape "${recommended_profile}")"
printf '    "command": "%s",\n' "$(json_escape "${recommended_command}")"
printf '    "notes": [%s]\n' "${notes_json}"
printf '  }\n'
printf '}\n'