#!/usr/bin/env python3
"""
热点趋势感知模块
- LLM 生成当前领域热点话题
- 可扩展接入外部热搜 API
"""

import json, datetime, logging, sys
from pathlib import Path
from typing import List, Dict

PROJECT_ROOT = Path(__file__).parent.parent
sys.path.insert(0, str(PROJECT_ROOT))
sys.path.insert(0, str(PROJECT_ROOT / "platform" / "backend"))

from app.core.nvidia_client import call_llm

DATA_DIR = PROJECT_ROOT / "automation" / "data"
TRENDS_FILE = DATA_DIR / "trends.json"
LOGS_DIR = PROJECT_ROOT / "automation" / "logs"
TODAY = datetime.datetime.now().strftime("%Y-%m-%d")

logging.basicConfig(
    level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s',
    handlers=[logging.FileHandler(LOGS_DIR / f"trends_{TODAY}.log"), logging.StreamHandler()]
)
logger = logging.getLogger(__name__)

DOMAINS = ["远程工作", "AI工具", "可持续生活", "知识管理", "数字生活", "科技人文"]

def fetch_llm_trends() -> List[Dict]:
    prompt = f"""你是中文互联网趋势分析师，擅长发现真正有价值、能出爆款的热点话题。请列出今天（2026年5月）中文互联网上最值得创作的10个话题。

要求：
1. 覆盖领域：{', '.join(DOMAINS)}
2. 每个话题必须从「真实用户」角度出发——不是学术热门，而是普通人正在搜、在讨论的
3. 判断依据：知乎有高赞讨论？小红书有爆款笔记趋势？微信有刷屏文章？
4. SEO价值：这个话题是否有持续搜索量，还是纯短期流量？
5. 每个话题需包含：
   - "domain": 领域
   - "topic": 话题名称（老百姓能听懂的说法）
   - "reason": 为什么现在讨论这个（1句话，说人话，有具体事件/数据支撑）
   - "hot_keywords": 用户真实搜索时会用的词（3-5个，包含1-2个长尾词）
   - "platform": 最适合分发此话题的平台（知乎/小红书/微信/多平台）
   - "seo_angle": 从什么角度切入能获得搜索流量（1句话）
   - "engagement": 预估互动潜力（高/中/低）

输出 JSON 数组：
[{{"domain": "领域", "topic": "话题名", "reason": "热度原因", "hot_keywords": ["词1","词2","词3"], "platform": "知乎/小红书/微信/多平台", "seo_angle": "SEO切入点", "engagement": "高/中/低"}}]

只输出 JSON，不要其他文字。"""
    try:
        resp = call_llm(prompt, temperature=0.4)
        resp = resp.strip()
        if resp.startswith("```"):
            resp = resp.split("\n", 1)[1].rsplit("\n", 1)[0]
        trends = json.loads(resp)
        if isinstance(trends, list):
            return trends
    except Exception as e:
        logger.warning(f"LLM 趋势获取失败: {e}")
    return []

def save_trends(trends: List[Dict]):
    data = {
        "date": TODAY,
        "updated_at": datetime.datetime.now().isoformat(),
        "trends": trends
    }
    DATA_DIR.mkdir(parents=True, exist_ok=True)
    TRENDS_FILE.write_text(json.dumps(data, ensure_ascii=False, indent=2), encoding='utf-8')
    logger.info(f"趋势数据已保存: {len(trends)} 条")

def load_trends() -> List[Dict]:
    if TRENDS_FILE.exists():
        try:
            data = json.loads(TRENDS_FILE.read_text(encoding='utf-8'))
            if data.get("date") == TODAY:
                return data.get("trends", [])
        except:
            pass
    return []

def get_trending_topics(domain: str = None, top_k: int = 5) -> List[Dict]:
    trends = load_trends()
    if domain:
        trends = [t for t in trends if domain in t.get("domain", "") or t.get("domain", "") in domain]
    return trends[:top_k]

def get_trend_context(domain: str = None) -> str:
    trends = get_trending_topics(domain, top_k=3)
    if not trends:
        return "暂无趋势数据"
    lines = ["## 当前热点趋势", ""]
    for t in trends:
        keywords = ", ".join(t.get("hot_keywords", []))
        lines.append(f"- **{t['topic']}**（{t.get('platform','')}）：{t.get('reason','')}")
        if keywords:
            lines.append(f"  热搜词：{keywords}")
    return "\n".join(lines)

def main():
    logger.info("开始获取热点趋势...")
    trends = fetch_llm_trends()
    if trends:
        save_trends(trends)
        for t in trends:
            print(f"  [{t.get('domain','?')}] {t['topic']} — {t.get('platform','')}")
    else:
        print("未获取到趋势数据")
    print(f"完成，共 {len(trends)} 条")

if __name__ == "__main__":
    main()