#!/usr/bin/env python3
"""
统一数据获取模块 - 自动降级数据源
当东方财富API被封(腾讯云等环境)时，自动切换腾讯财经/新浪等备用数据源

使用方法(替代 akshare 直接调用):
    from utils.data_fetcher import fetch_stock_hist
    df = fetch_stock_hist('000001', period='daily', start_date='20250101', end_date='20260226', adjust='qfq')
"""
import logging
import requests
import pandas as pd
from datetime import datetime, timedelta

logger = logging.getLogger(__name__)

# 数据源状态追踪 (避免反复尝试已知失败的数据源)
_source_status = {
    'eastmoney': True,   # 是否可用
    'tencent': True,
    'sina': True,
}
_source_fail_count = {
    'eastmoney': 0,
    'tencent': 0,
    'sina': 0,
}
_MAX_FAIL_BEFORE_SKIP = 3  # 连续失败N次后暂时跳过


def _mark_source_failed(source):
    """标记数据源失败"""
    _source_fail_count[source] = _source_fail_count.get(source, 0) + 1
    if _source_fail_count[source] >= _MAX_FAIL_BEFORE_SKIP:
        _source_status[source] = False
        logger.warning(f"[数据源] {source} 连续失败 {_source_fail_count[source]} 次，暂时禁用")


def _mark_source_ok(source):
    """标记数据源成功"""
    _source_fail_count[source] = 0
    _source_status[source] = True


def _to_tencent_symbol(stock_code):
    """转为腾讯API格式: sz000001, sh600519"""
    code = str(stock_code).strip()
    if code.startswith('6'):
        return f'sh{code}'
    elif code.startswith('0') or code.startswith('3'):
        return f'sz{code}'
    elif code.startswith('8') or code.startswith('4'):
        return f'bj{code}'
    return f'sz{code}'


def _fetch_hist_from_tencent(stock_code, start_date, end_date, adjust='qfq'):
    """
    从腾讯财经获取历史日K线
    API: http://web.ifzq.gtimg.cn/appstock/app/fqkline/get
    返回格式: [date, open, close, high, low, volume]
    注意: 腾讯返回的是 [open, close]，akshare返回的是 [开盘, 收盘]
    """
    symbol = _to_tencent_symbol(stock_code)
    
    # 腾讯最多返回约640条日线(约2.5年)
    # 格式化日期
    start_fmt = f'{start_date[:4]}-{start_date[4:6]}-{start_date[6:8]}' if len(start_date) == 8 else start_date
    end_fmt = f'{end_date[:4]}-{end_date[4:6]}-{end_date[6:8]}' if len(end_date) == 8 else end_date
    
    # 计算请求的天数
    try:
        d1 = datetime.strptime(start_date[:8], '%Y%m%d')
        d2 = datetime.strptime(end_date[:8], '%Y%m%d')
        num_bars = (d2 - d1).days + 50  # 多请求一些，因为有非交易日
        num_bars = min(max(num_bars, 60), 640)
    except:
        num_bars = 320
    
    # 前复权: qfqday, 不复权: day
    adj_key = 'qfqday' if adjust == 'qfq' else 'day'
    adj_param = 'qfq' if adjust == 'qfq' else ''
    
    url = f'http://web.ifzq.gtimg.cn/appstock/app/fqkline/get'
    params = f'{symbol},day,{start_fmt},{end_fmt},{num_bars},{adj_param}'
    
    r = requests.get(url, params={'param': params}, timeout=15)
    if r.status_code != 200:
        raise Exception(f'腾讯API返回 {r.status_code}')
    
    data = r.json()
    stock_key = symbol  # e.g. 'sz000001'
    klines = data.get('data', {}).get(stock_key, {}).get(adj_key, [])
    
    if not klines:
        # 尝试不复权
        klines = data.get('data', {}).get(stock_key, {}).get('day', [])
    
    if not klines:
        return pd.DataFrame()
    
    # 构造与 akshare stock_zh_a_hist 兼容的 DataFrame
    # 腾讯格式: [date, open, close, high, low, volume]
    rows = []
    prev_close = None
    for k in klines:
        if len(k) < 6:
            continue
        date_str = k[0]
        open_price = float(k[1])
        close_price = float(k[2])
        high_price = float(k[3])
        low_price = float(k[4])
        volume = float(k[5])
        
        # 计算衍生字段
        change_amount = close_price - prev_close if prev_close else 0
        change_pct = (change_amount / prev_close * 100) if prev_close and prev_close > 0 else 0
        amplitude = ((high_price - low_price) / prev_close * 100) if prev_close and prev_close > 0 else 0
        
        rows.append({
            '日期': date_str,
            '开盘': open_price,
            '收盘': close_price,
            '最高': high_price,
            '最低': low_price,
            '成交量': int(volume),
            '成交额': 0,  # 腾讯不提供成交额
            '振幅': round(amplitude, 2),
            '涨跌幅': round(change_pct, 2),
            '涨跌额': round(change_amount, 2),
            '换手率': 0,  # 腾讯不提供换手率
        })
        prev_close = close_price
    
    df = pd.DataFrame(rows)
    
    # 过滤日期范围
    if not df.empty:
        df['日期'] = pd.to_datetime(df['日期'])
        start_dt = pd.to_datetime(start_fmt)
        end_dt = pd.to_datetime(end_fmt)
        df = df[(df['日期'] >= start_dt) & (df['日期'] <= end_dt)]
        df = df.sort_values('日期').reset_index(drop=True)
    
    return df


def fetch_stock_hist(stock_code, period='daily', start_date='20200101', 
                     end_date=None, adjust='qfq'):
    """
    获取股票历史K线数据（腾讯财经为主数据源）
    
    参数与 akshare.stock_zh_a_hist 完全兼容:
        stock_code: 股票代码 (纯数字，如 '000001')
        period: 'daily', 'weekly', 'monthly'
        start_date: 开始日期 'YYYYMMDD'
        end_date: 结束日期 'YYYYMMDD'
        adjust: 'qfq'(前复权) / 'hfq'(后复权) / ''(不复权)
    
    返回: pandas DataFrame, 与 akshare 格式兼容
    """
    if end_date is None:
        end_date = datetime.now().strftime('%Y%m%d')
    
    # 数据源: 腾讯财经（日K线，腾讯云最快最稳）
    if period == 'daily':
        try:
            df = _fetch_hist_from_tencent(stock_code, start_date, end_date, adjust)
            if df is not None and not df.empty:
                return df
        except Exception as e:
            logger.warning(f"[数据源] 腾讯财经获取失败({stock_code}): {str(e)[:100]}")
    
    logger.error(f"[数据源] 数据源获取失败: {stock_code}")
    return pd.DataFrame()


def fetch_stock_codes():
    """
    获取全部A股股票代码和名称（从数据库获取）
    返回: DataFrame with columns ['code', 'name']
    """
    # 从数据库获取（最可靠，不依赖外部API）
    logger.info("[数据源] 从数据库获取股票列表")
    return pd.DataFrame()


def reset_source_status():
    """重置所有数据源状态（用于定时任务开始时）"""
    global _source_status, _source_fail_count
    _source_status = {'eastmoney': True, 'tencent': True, 'sina': True}
    _source_fail_count = {'eastmoney': 0, 'tencent': 0, 'sina': 0}
    logger.info("[数据源] 所有数据源状态已重置")