#!/usr/bin/env python3
"""
AWOOOI Sensor Agent - Phase 6.5 神經末梢
=========================================

極度輕量的告警採集代理，部署於各主機。
唯一職責：採集本地告警 → 無腦轉發至 188 基地 Event Bus

設計鐵律：
- 嚴禁 Incident/GraphRAG 邏輯 (防腦分裂)
- 零依賴 AWOOOI 核心資料庫
- 純 Python + Redis 即可運行

使用方式：
    # 設定環境變數
    export AWOOOI_REDIS_URL="redis://192.168.68.188:6379/0"

    # 執行代理 (發送模擬告警)
    python agent.py

    # 持續監控模式 (每 30 秒發送一次)
    python agent.py --loop --interval 30

Version: 1.0.0
Date: 2026-03-22
"""

import argparse
import json
import os
import random
import socket
import sys
import time
from datetime import datetime, timedelta, timezone

# 台北時區 (UTC+8) - 系統統一時區
TAIPEI_TZ = timezone(timedelta(hours=8))
from typing import Any
from uuid import uuid4

# ============================================================================
# 唯一外部依賴：redis-py (pip install redis)
# ============================================================================
try:
    import redis
except ImportError:
    print("[FATAL] redis-py not installed. Run: pip install redis")
    sys.exit(1)


# ============================================================================
# 常量定義
# ============================================================================
STREAM_NAME = "stream:awoooi_signals"
DEFAULT_REDIS_URL = "redis://192.168.68.188:6379/0"

# 模擬告警模板 (實際部署時會讀取 Prometheus/Alertmanager)
MOCK_ALERTS = [
    {
        "alert_name": "PodCrashLoopBackOff",
        "severity": "critical",
        "source": "prometheus",
        "namespace": "production",
        "target": "payment-service",
    },
    {
        "alert_name": "HighLatencyP99",
        "severity": "warning",
        "source": "prometheus",
        "namespace": "production",
        "target": "api-gateway",
    },
    {
        "alert_name": "HighErrorRate",
        "severity": "critical",
        "source": "prometheus",
        "namespace": "staging",
        "target": "order-service",
    },
    {
        "alert_name": "MemoryPressure",
        "severity": "warning",
        "source": "node-exporter",
        "namespace": "infra",
        "target": "k3s-worker-01",
    },
    {
        "alert_name": "FINAL_PHASE_6_TEST",
        "severity": "critical",
        "source": "sensor-agent",
        "namespace": "production",
        "target": "awoooi-brain",
    },
]


# ============================================================================
# Sensor Agent Core
# ============================================================================

class SensorAgent:
    """
    神經末梢 - 極簡告警採集代理

    職責：
    1. 採集本地告警 (或模擬生成)
    2. 格式化為標準 Signal
    3. 透過 Redis XADD 打入 188 基地 Event Bus

    嚴禁邏輯：
    - Incident 聚合 (由 188 大腦負責)
    - GraphRAG 分析 (由 188 大腦負責)
    - 任何決策邏輯 (由 188 大腦負責)
    """

    def __init__(self, redis_url: str | None = None) -> None:
        self.redis_url = redis_url or os.getenv("AWOOOI_REDIS_URL", DEFAULT_REDIS_URL)
        self.hostname = socket.gethostname()
        self.sensor_id = f"sensor-{self.hostname}"
        self._redis: redis.Redis | None = None

    def connect(self) -> bool:
        """連線至 188 基地 Redis"""
        try:
            self._redis = redis.from_url(
                self.redis_url,
                decode_responses=True,
                socket_connect_timeout=5,
            )
            # 測試連線
            self._redis.ping()
            print(f"[OK] Connected to 188 Event Bus: {self._mask_url(self.redis_url)}")
            return True
        except redis.ConnectionError as e:
            print(f"[FATAL] Cannot connect to 188 Event Bus: {e}")
            return False

    def _mask_url(self, url: str) -> str:
        """遮蔽密碼"""
        if "@" in url:
            parts = url.split("@")
            return f"redis://***@{parts[-1]}"
        return url

    def send_signal(self, alert: dict[str, Any]) -> str | None:
        """
        發送單一 Signal 至 Event Bus

        無腦轉發邏輯：
        1. 補齊必要欄位 (fingerprint, timestamp, sensor_id)
        2. 直接 XADD 到 stream:awoooi_signals
        3. 返回 message_id 或 None

        Args:
            alert: 告警字典 (至少需 alert_name, severity, source)

        Returns:
            Redis Stream message ID or None
        """
        if not self._redis:
            print("[ERROR] Not connected to Redis")
            return None

        # 建立標準 Signal 格式
        now = datetime.now(TAIPEI_TZ)
        signal = {
            "alert_name": alert.get("alert_name", "UnknownAlert"),
            "severity": alert.get("severity", "warning"),
            "source": alert.get("source", "sensor-agent"),
            "namespace": alert.get("namespace", "default"),
            "target": alert.get("target", "unknown"),
            "fingerprint": alert.get("fingerprint", f"fp_{uuid4().hex[:12]}"),
            "labels": json.dumps(alert.get("labels", {"sensor_id": self.sensor_id})),
            "annotations": json.dumps(alert.get("annotations", {})),
            "received_at": now.isoformat(),
            "sensor_id": self.sensor_id,
            "sensor_host": self.hostname,
        }

        try:
            # 無腦 XADD - 直接打入 188 基地
            message_id = self._redis.xadd(STREAM_NAME, signal)
            return message_id
        except redis.RedisError as e:
            print(f"[ERROR] XADD failed: {e}")
            return None

    def fire_mock_alert(self, alert_name: str | None = None) -> str | None:
        """
        發射模擬告警 (測試用)

        Args:
            alert_name: 指定告警名稱，或隨機選擇

        Returns:
            message_id or None
        """
        if alert_name:
            # 尋找指定告警
            alert = next(
                (a for a in MOCK_ALERTS if a["alert_name"] == alert_name),
                MOCK_ALERTS[-1],  # 預設使用 FINAL_PHASE_6_TEST
            )
        else:
            alert = random.choice(MOCK_ALERTS)

        print(f"\n[FIRE] Sending alert: {alert['alert_name']}")
        print(f"       Severity: {alert['severity']}")
        print(f"       Target: {alert['namespace']}/{alert['target']}")
        print(f"       Sensor: {self.sensor_id}")

        message_id = self.send_signal(alert)

        if message_id:
            print(f"[OK] Signal delivered to 188 Event Bus")
            print(f"     Stream: {STREAM_NAME}")
            print(f"     Message ID: {message_id}")
        else:
            print(f"[FAIL] Signal delivery failed!")

        return message_id

    def close(self) -> None:
        """關閉連線"""
        if self._redis:
            self._redis.close()
            print("[OK] Disconnected from 188 Event Bus")


# ============================================================================
# CLI Entry Point
# ============================================================================

def main() -> int:
    parser = argparse.ArgumentParser(
        description="AWOOOI Sensor Agent - 神經末梢告警採集代理"
    )
    parser.add_argument(
        "--alert",
        type=str,
        default="FINAL_PHASE_6_TEST",
        help="告警名稱 (預設: FINAL_PHASE_6_TEST)",
    )
    parser.add_argument(
        "--loop",
        action="store_true",
        help="持續監控模式",
    )
    parser.add_argument(
        "--interval",
        type=int,
        default=30,
        help="監控間隔秒數 (預設: 30)",
    )
    parser.add_argument(
        "--redis-url",
        type=str,
        help="Redis URL (預設讀取 AWOOOI_REDIS_URL 環境變數)",
    )

    args = parser.parse_args()

    print("=" * 70)
    print("AWOOOI Sensor Agent - Phase 6.5 神經末梢")
    print("=" * 70)
    print(f"Time: {datetime.now(TAIPEI_TZ).isoformat()}")
    print(f"Host: {socket.gethostname()}")
    print()

    # 初始化 Agent
    agent = SensorAgent(redis_url=args.redis_url)

    if not agent.connect():
        return 1

    try:
        if args.loop:
            # 持續監控模式
            print(f"\n[LOOP] Continuous mode: sending random alert every {args.interval}s")
            print("[LOOP] Press Ctrl+C to stop\n")
            while True:
                agent.fire_mock_alert()
                time.sleep(args.interval)
        else:
            # 單發模式
            message_id = agent.fire_mock_alert(alert_name=args.alert)
            if not message_id:
                return 1

    except KeyboardInterrupt:
        print("\n[STOP] Interrupted by user")

    finally:
        agent.close()

    print("\n" + "=" * 70)
    print("Sensor Agent terminated")
    print("=" * 70)

    return 0


if __name__ == "__main__":
    sys.exit(main())