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

usage() {
  cat >&2 <<'EOF'
用法:
  jenkins-inbound-agent-start <agent-name>

说明:
  该脚本由 systemd 调用，读取 /etc/jenkins-agent/<agent-name>.env，
  下载 Jenkins agent.jar，并通过 inbound WebSocket 连接 Jenkins controller。
EOF
}

AGENT_INSTANCE="${1:-}"
if [[ -z "${AGENT_INSTANCE}" ]]; then
  usage
  exit 2
fi

CONFIG_FILE="${JENKINS_AGENT_CONFIG_FILE:-/etc/jenkins-agent/${AGENT_INSTANCE}.env}"
if [[ ! -r "${CONFIG_FILE}" ]]; then
  echo "[jenkins-agent] 配置文件不可读: ${CONFIG_FILE}" >&2
  exit 1
fi

set -a
# shellcheck disable=SC1090
source "${CONFIG_FILE}"
set +a

JENKINS_AGENT_NAME="${JENKINS_AGENT_NAME:-${AGENT_INSTANCE}}"
JENKINS_AGENT_WORKDIR="${JENKINS_AGENT_WORKDIR:-/var/lib/jenkins/agent/${JENKINS_AGENT_NAME}}"
JENKINS_AGENT_JAR="${JENKINS_AGENT_JAR:-/opt/jenkins-agent/agent.jar}"
JENKINS_AGENT_SECRET_FILE="${JENKINS_AGENT_SECRET_FILE:-/etc/jenkins-agent/${JENKINS_AGENT_NAME}.secret}"
JENKINS_AGENT_USE_WEBSOCKET="${JENKINS_AGENT_USE_WEBSOCKET:-true}"
JENKINS_AGENT_JAVA_BIN="${JENKINS_AGENT_JAVA_BIN:-java}"

if [[ -z "${JENKINS_URL:-}" ]]; then
  echo "[jenkins-agent] JENKINS_URL 不能为空。" >&2
  exit 1
fi

if [[ -z "${JENKINS_AGENT_SECRET:-}" ]]; then
  if [[ ! -r "${JENKINS_AGENT_SECRET_FILE}" ]]; then
    echo "[jenkins-agent] 未提供 JENKINS_AGENT_SECRET，且密钥文件不可读: ${JENKINS_AGENT_SECRET_FILE}" >&2
    exit 1
  fi
  JENKINS_AGENT_SECRET="$(tr -d '\r\n' <"${JENKINS_AGENT_SECRET_FILE}")"
fi

if [[ -z "${JENKINS_AGENT_SECRET}" ]]; then
  echo "[jenkins-agent] Jenkins inbound agent secret 不能为空。" >&2
  exit 1
fi

mkdir -p "$(dirname "${JENKINS_AGENT_JAR}")" "${JENKINS_AGENT_WORKDIR}"

AGENT_JAR_URL="${JENKINS_URL%/}/jnlpJars/agent.jar"
AGENT_JAR_TMP="${JENKINS_AGENT_JAR}.tmp"

echo "[jenkins-agent] 下载 agent.jar: ${AGENT_JAR_URL}"
curl -fsSL --retry 5 --retry-delay 5 "${AGENT_JAR_URL}" -o "${AGENT_JAR_TMP}"
mv "${AGENT_JAR_TMP}" "${JENKINS_AGENT_JAR}"

agent_args=(
  "${JENKINS_AGENT_JAVA_BIN}"
  -jar "${JENKINS_AGENT_JAR}"
  -url "${JENKINS_URL}"
  -secret "${JENKINS_AGENT_SECRET}"
  -name "${JENKINS_AGENT_NAME}"
  -workDir "${JENKINS_AGENT_WORKDIR}"
)

if [[ "${JENKINS_AGENT_USE_WEBSOCKET}" == "true" ]]; then
  agent_args+=(-webSocket)
fi

echo "[jenkins-agent] 启动 inbound agent: ${JENKINS_AGENT_NAME}"
exec "${agent_args[@]}"