#!/usr/bin/env sh
set -eu

INSTALL_DIR="${PLATFORM_AGENT_DIR:-/opt/platform-agent}"
SERVICE_NAME="${PLATFORM_AGENT_SERVICE:-platform-agent}"
CONFIG_PATH="${AGENT_CONFIG:-${INSTALL_DIR}/agent.config.json}"
SERVICE_FILE="/etc/systemd/system/${SERVICE_NAME}.service"

log() {
  printf '%s\n' "$*"
}

need_cmd() {
  command -v "$1" >/dev/null 2>&1
}

as_root() {
  if [ "$(id -u)" -eq 0 ]; then
    "$@"
  elif need_cmd sudo; then
    sudo "$@"
  else
    log "Root privileges are required: $*"
    exit 1
  fi
}

prompt_value() {
  var_name="$1"
  label="$2"
  current_value="$3"
  secret="${4:-false}"
  if [ "$secret" = "true" ]; then
    printf '%s [hidden, Enter keeps current]: ' "$label"
    stty -echo 2>/dev/null || true
    IFS= read -r answer || answer=""
    stty echo 2>/dev/null || true
    printf '\n'
  else
    printf '%s [%s]: ' "$label" "$current_value"
    IFS= read -r answer || answer=""
  fi
  if [ -n "$answer" ]; then
    eval "$var_name=\"\$answer\""
  fi
}

prompt_yes_no() {
  label="$1"
  default="${2:-no}"
  suffix="[y/N]"
  [ "$default" = "yes" ] && suffix="[Y/n]"
  printf '%s %s ' "$label" "$suffix"
  IFS= read -r answer || answer=""
  answer="$(printf '%s' "$answer" | tr '[:upper:]' '[:lower:]')"
  if [ -z "$answer" ]; then
    [ "$default" = "yes" ]
    return
  fi
  [ "$answer" = "y" ] || [ "$answer" = "yes" ]
}

json_get() {
  key_path="$1"
  fallback="${2:-}"
  python3 - "$CONFIG_PATH" "$key_path" "$fallback" <<'PY'
import json
import sys

path, key_path, fallback = sys.argv[1], sys.argv[2], sys.argv[3]
try:
    with open(path, "r", encoding="utf-8") as fp:
        value = json.load(fp)
except Exception:
    print(fallback)
    raise SystemExit

for key in key_path.split("."):
    if not isinstance(value, dict):
        value = None
        break
    value = value.get(key)

if value is None:
    print(fallback)
elif isinstance(value, bool):
    print("true" if value else "false")
else:
    print(value)
PY
}

service_user() {
  if [ -f "$SERVICE_FILE" ]; then
    user_line="$(sed -n 's/^User=//p' "$SERVICE_FILE" | head -n 1)"
    [ -n "$user_line" ] && {
      printf '%s' "$user_line"
      return
    }
  fi
  id -un
}

expand_path_for_user() {
  path="$1"
  run_user="$2"
  case "$path" in
    "~")
      if [ "$run_user" = "root" ]; then printf '/root'; else printf '/home/%s' "$run_user"; fi
      ;;
    "~/"*)
      if [ "$run_user" = "root" ]; then printf '/root/%s' "${path#~/}"; else printf '/home/%s/%s' "$run_user" "${path#~/}"; fi
      ;;
    *)
      printf '%s' "$path"
      ;;
  esac
}

write_config() {
  tmp_file="$(mktemp)"
  WORKSPACE_ROOT="$WORKSPACE_ROOT" \
  ROBOT_STACK="$ROBOT_STACK" \
  ROS_DOMAIN_ID="$ROS_DOMAIN_ID" \
  CAMERA_ENABLED="$CAMERA_ENABLED" \
  CAMERA_VIDEO_DEVICE="$CAMERA_VIDEO_DEVICE" \
  CAMERA_SIGNALING_URL="$CAMERA_SIGNALING_URL" \
  KASMVNC_GEOMETRY="$KASMVNC_GEOMETRY" \
  AGENT_GATEWAY_TOKEN="$AGENT_GATEWAY_TOKEN" \
  python3 - "$CONFIG_PATH" "$tmp_file" <<'PY'
import json
import os
import sys

source, target = sys.argv[1], sys.argv[2]
with open(source, "r", encoding="utf-8") as fp:
    cfg = json.load(fp)

cfg.setdefault("workspace", {})
cfg.setdefault("ros", {})
cfg.setdefault("camera", {})
cfg.setdefault("desktop", {})
cfg.setdefault("security", {})

cfg["workspace"]["root"] = os.environ["WORKSPACE_ROOT"]
cfg["ros"]["stack"] = "nav2" if os.environ["ROBOT_STACK"].lower() == "nav2" else "autoware"
cfg["ros"]["domainId"] = os.environ["ROS_DOMAIN_ID"] if os.environ["ROS_DOMAIN_ID"].isdigit() else "0"
cfg["camera"]["enabled"] = os.environ["CAMERA_ENABLED"].lower() in ("true", "1", "yes", "y", "on")
cfg["camera"]["videoDevice"] = os.environ["CAMERA_VIDEO_DEVICE"]
cfg["camera"]["signalingUrl"] = os.environ["CAMERA_SIGNALING_URL"]
cfg["desktop"]["geometry"] = os.environ["KASMVNC_GEOMETRY"]
if os.environ["AGENT_GATEWAY_TOKEN"]:
    cfg["security"]["gatewayToken"] = os.environ["AGENT_GATEWAY_TOKEN"]

with open(target, "w", encoding="utf-8") as fp:
    json.dump(cfg, fp, ensure_ascii=False, indent=2)
    fp.write("\n")
PY
  as_root cp "$tmp_file" "$CONFIG_PATH"
  rm -f "$tmp_file"
}

restart_service() {
  if need_cmd systemctl; then
    as_root systemctl restart "$SERVICE_NAME"
  elif need_cmd service; then
    as_root service "$SERVICE_NAME" restart
  else
    log "No service manager found. Restart the agent manually."
  fi
}

if ! need_cmd python3; then
  log "python3 is required to edit ${CONFIG_PATH}."
  exit 1
fi

if [ ! -f "$CONFIG_PATH" ]; then
  log "Config not found: ${CONFIG_PATH}"
  log "Set AGENT_CONFIG=/path/to/agent.config.json or install the agent first."
  exit 1
fi

RUN_USER="$(service_user)"
WORKSPACE_ROOT="$(json_get workspace.root '~/autonomy-studio/workspaces')"
ROBOT_STACK="$(json_get ros.stack autoware)"
ROS_DOMAIN_ID="$(json_get ros.domainId 0)"
CAMERA_ENABLED="$(json_get camera.enabled false)"
CAMERA_VIDEO_DEVICE="$(json_get camera.videoDevice /dev/video0)"
CAMERA_SIGNALING_URL="$(json_get camera.signalingUrl ws://127.0.0.1:3000)"
KASMVNC_GEOMETRY="$(json_get desktop.geometry 1600x900)"
AGENT_GATEWAY_TOKEN="$(json_get security.gatewayToken '')"

while :; do
  clear
  log "Autonomy Studio Platform Agent Settings"
  log "======================================="
  log "Config  : ${CONFIG_PATH}"
  log "Service : ${SERVICE_NAME}"
  log ""
  log "1. Workspace root      ${WORKSPACE_ROOT}"
  log "2. ROS stack           ${ROBOT_STACK}"
  log "3. ROS_DOMAIN_ID       ${ROS_DOMAIN_ID}"
  log "4. Camera enabled      ${CAMERA_ENABLED}"
  log "5. Camera device       ${CAMERA_VIDEO_DEVICE}"
  log "6. Camera signaling    ${CAMERA_SIGNALING_URL}"
  log "7. KasmVNC resolution  ${KASMVNC_GEOMETRY}"
  log "8. Gateway token       $(if [ -n "$AGENT_GATEWAY_TOKEN" ]; then printf 'configured'; else printf 'empty'; fi)"
  log ""
  log "s. Save and restart"
  log "q. Quit"
  log ""
  printf 'Select: '
  IFS= read -r choice || choice=""
  case "$choice" in
    1)
      prompt_value WORKSPACE_ROOT "Workspace root" "$WORKSPACE_ROOT"
      ;;
    2)
      prompt_value ROBOT_STACK "ROS stack (autoware/nav2)" "$ROBOT_STACK"
      case "$ROBOT_STACK" in
        nav2|NAV2) ROBOT_STACK="nav2" ;;
        *) ROBOT_STACK="autoware" ;;
      esac
      ;;
    3)
      prompt_value ROS_DOMAIN_ID "ROS_DOMAIN_ID" "$ROS_DOMAIN_ID"
      ROS_DOMAIN_ID="$(printf '%s' "$ROS_DOMAIN_ID" | tr -cd '0-9')"
      [ -n "$ROS_DOMAIN_ID" ] || ROS_DOMAIN_ID="0"
      ;;
    4)
      prompt_value CAMERA_ENABLED "Camera enabled true/false" "$CAMERA_ENABLED"
      ;;
    5)
      prompt_value CAMERA_VIDEO_DEVICE "Camera device" "$CAMERA_VIDEO_DEVICE"
      ;;
    6)
      prompt_value CAMERA_SIGNALING_URL "Camera signaling URL" "$CAMERA_SIGNALING_URL"
      ;;
    7)
      prompt_value KASMVNC_GEOMETRY "KasmVNC resolution" "$KASMVNC_GEOMETRY"
      ;;
    8)
      prompt_value AGENT_GATEWAY_TOKEN "Gateway token" "$AGENT_GATEWAY_TOKEN" true
      ;;
    s|S)
      write_config
      workspace_path="$(expand_path_for_user "$WORKSPACE_ROOT" "$RUN_USER")"
      if prompt_yes_no "Create workspace directory ${workspace_path} if missing?" "yes"; then
        as_root mkdir -p "$workspace_path"
        as_root chown -R "$RUN_USER":"$RUN_USER" "$workspace_path" || true
      fi
      restart_service
      log ""
      log "Settings saved and service restarted."
      exit 0
      ;;
    q|Q)
      log "Canceled."
      exit 0
      ;;
  esac
done