const calculateMA = (data, period) => {
  if (!data || data.length < period) return null
  const subset = data.slice(-period)
  const sum = subset.reduce((a, b) => a + b, 0)
  return sum / period
}

const calculateTrailingMA = (data, endExclusive, period) => {
  if (!Array.isArray(data) || period <= 0) return null
  if (!Number.isInteger(endExclusive) || endExclusive < period) return null
  const subset = data.slice(endExclusive - period, endExclusive)
  if (subset.length < period) return null
  const sum = subset.reduce((a, b) => a + b, 0)
  return sum / period
}

const fetchKLine = async (axios, symbol) => {
  const url = `http://web.ifzq.gtimg.cn/appstock/app/fqkline/get?param=${symbol},day,,,300,qfq`
  try {
    const res = await axios.get(url, { timeout: 10000 })
    if (!res || !res.data || res.data.code !== 0) return null
    const d = res.data.data[symbol]
    if (!d) return null
    const rawData = d.qfqday || d.day
    if (!rawData || !Array.isArray(rawData)) return null
    return rawData.map(item => {
      const volume = parseFloat(item[5])
      return {
        date: item[0],
        close: parseFloat(item[2]),
        volume: Number.isFinite(volume) ? volume : 0
      }
    })
  } catch (e) {
    return null
  }
}

const buildAlerts = ({
  latestClose,
  prevClose,
  ma10,
  ma20,
  ma60,
  ma90,
  ma250,
  prevMA20,
  prevMA60,
  prevMA90,
  prevMA250,
  isTrendGateOpen,
  boxBreakoutConfirmed,
  boxBreakdownConfirmed
}) => {
  const alerts = []
  const addAlert = (id, title, message, level = 'warning') => {
    alerts.push({ id, title, message, level })
  }

  const isCrossDown = (prevC, prevMa, currC, currMa) => prevC >= prevMa && currC < currMa
  const isCrossUp = (prevC, prevMa, currC, currMa) => prevC <= prevMa && currC > currMa

  const isBelowMA250 = latestClose < ma250
  const isCrossDownMA250 = isCrossDown(prevClose, prevMA250, latestClose, ma250)
  const isCrossUpMA250 = isCrossUp(prevClose, prevMA250, latestClose, ma250)

  if (isCrossDownMA250) {
    addAlert('below_ma250', '中国银行跌破年线！立即停止加仓，建议减仓', '中国银行跌破年线！立即停止加仓，建议减仓', 'error')
  }
  if (isCrossUpMA250) {
    addAlert('above_ma250', '中国银行回到年线之上，可恢复加仓策略', '中国银行回到年线之上，可恢复加仓策略')
  }

  if (boxBreakoutConfirmed) {
    addAlert('box_breakout_confirmed', '箱体上沿突破已确认', '中国银行30日收盘价箱体上沿突破已连续2日确认，且突破日放量')
  }
  if (boxBreakdownConfirmed) {
    addAlert('box_breakdown_confirmed', '箱体下沿跌破已确认', '中国银行30日收盘价箱体下沿跌破已连续2日确认，建议防守', 'error')
  }

  if (isTrendGateOpen) {
    if (isCrossDown(prevClose, prevMA20, latestClose, ma20)) {
      addAlert('below_ma20', '中国银行-跌破20日线，需加仓 20%', '中国银行-跌破20日线，需加仓 20%')
    }
    if (isCrossDown(prevClose, prevMA60, latestClose, ma60)) {
      addAlert('below_ma60', '中国银行-跌破60日线，需加仓 40%', '中国银行-跌破60日线，需加仓 40%')
    }
    if (isCrossDown(prevClose, prevMA90, latestClose, ma90)) {
      addAlert('below_ma90', '中国银行-跌破90日线，需加仓剩余 40%', '中国银行-跌破90日线，需加仓剩余 40%')
    }
  }

  if (isCrossUp(prevClose, prevMA20, latestClose, ma20)) {
    addAlert('above_ma20', '中国银行-站上20日线，需卖出 20%', '中国银行-站上20日线，需卖出 20%')
  }
  if (isCrossUp(prevClose, prevMA60, latestClose, ma60)) {
    addAlert('above_ma60', '中国银行-站上60日线，需卖出 40%', '中国银行-站上60日线，需卖出 40%')
  }
  if (isCrossUp(prevClose, prevMA90, latestClose, ma90)) {
    addAlert('above_ma90', '中国银行-站上90日线，需卖出剩余 40%', '中国银行-站上90日线，需卖出剩余 40%')
  }

  if (ma10 > ma20) {
    addAlert('trend_bull', '趋势提示', '中国银行处于上涨趋势，建议持有底仓 + 已建波段仓，不做 T')
  }

  return alerts
}

module.exports = {
  run: async (context, config) => {
    const { axios, logJSON } = context
    const symbol = config.symbol
    const sourceSymbol = config.source_symbol || 'sh601988'

    const klineData = await fetchKLine(axios, sourceSymbol)
    if (!klineData || klineData.length < 250) {
      logJSON('skill.zhonghang_299.error', { message: 'Insufficient data', length: klineData ? klineData.length : 0 }, 'market_skills')
      return null
    }

    const closes = klineData.map(d => d.close)
    const volumes = klineData.map(d => d.volume)
    const latestClose = closes[closes.length - 1]
    const prevClose = closes[closes.length - 2]
    const prevPrevClose = closes[closes.length - 3]
    const latestDate = klineData[klineData.length - 1].date

    const ma10 = calculateMA(closes, 10)
    const ma20 = calculateMA(closes, 20)
    const ma60 = calculateMA(closes, 60)
    const ma90 = calculateMA(closes, 90)
    const ma250 = calculateMA(closes, 250)

    const closesPrev = closes.slice(0, -1)
    const prevMA20 = calculateMA(closesPrev, 20)
    const prevMA60 = calculateMA(closesPrev, 60)
    const prevMA90 = calculateMA(closesPrev, 90)
    const prevMA250 = calculateMA(closesPrev, 250)

    const boxWindowRaw = parseInt(String(config.box_window || 30), 10)
    const boxWindow = [20, 30, 40].includes(boxWindowRaw) ? boxWindowRaw : 30
    const confirmDaysRaw = parseInt(String(config.box_confirm_days || 2), 10)
    const confirmDays = confirmDaysRaw >= 2 ? 2 : 1
    const volumeMAWindowRaw = parseInt(String(config.box_volume_ma_window || 5), 10)
    const volumeMAWindow = volumeMAWindowRaw > 0 ? volumeMAWindowRaw : 5
    const volumeExpandRatioRaw = parseFloat(String(config.box_volume_expand_ratio || 1.2))
    const volumeExpandRatio = Number.isFinite(volumeExpandRatioRaw) && volumeExpandRatioRaw > 0 ? volumeExpandRatioRaw : 1.2

    if (!ma10 || !ma20 || !ma60 || !ma90 || !ma250 || !prevMA20 || !prevMA60 || !prevMA90 || !prevMA250) {
      logJSON('skill.zhonghang_299.error', { message: 'MA calculation failed' }, 'market_skills')
      return null
    }

    if (!Number.isFinite(prevPrevClose) || closes.length < boxWindow + 2) {
      logJSON('skill.zhonghang_299.error', { message: 'Insufficient data for box', length: closes.length, boxWindow }, 'market_skills')
      return null
    }

    const change = latestClose - prevClose
    const changePercent = (change / prevClose) * 100
    const trendText = ma10 > ma20 ? '多头排列' : '非多头'
    const yearLineText = latestClose < ma250 ? '年线下方' : '年线之上'
    const isCrossDown = (prevC, prevMa, currC, currMa) => prevC >= prevMa && currC < currMa
    const isCrossUp = (prevC, prevMa, currC, currMa) => prevC <= prevMa && currC > currMa
    const isBelowMA250 = latestClose < ma250
    const isMA250SlopeUp = ma250 >= prevMA250
    const isMA60SlopeUp = ma60 >= prevMA60
    const latestIndex = closes.length - 1
    const prevIndex = closes.length - 2
    const getBoxUpper = idx => Math.max(...closes.slice(idx - boxWindow, idx))
    const getBoxLower = idx => Math.min(...closes.slice(idx - boxWindow, idx))
    const upperPrev = getBoxUpper(prevIndex)
    const upperLatest = getBoxUpper(latestIndex)
    const lowerPrev = getBoxLower(prevIndex)
    const lowerLatest = getBoxLower(latestIndex)
    const prevVolume = volumes[prevIndex]
    const latestVolume = volumes[latestIndex]
    const prevVolumeMA = calculateTrailingMA(volumes, prevIndex, volumeMAWindow)
    const latestVolumeMA = calculateTrailingMA(volumes, latestIndex, volumeMAWindow)
    const breakoutDayPrev = prevPrevClose <= upperPrev && prevClose > upperPrev
    const breakdownDayPrev = prevPrevClose >= lowerPrev && prevClose < lowerPrev
    const breakoutVolumeOkPrev = Number.isFinite(prevVolumeMA) ? prevVolume > prevVolumeMA * volumeExpandRatio : false
    const breakoutDayLatest = prevClose <= upperLatest && latestClose > upperLatest
    const breakoutVolumeOkLatest = Number.isFinite(latestVolumeMA) ? latestVolume > latestVolumeMA * volumeExpandRatio : false
    const boxBreakoutConfirmed = confirmDays === 2
      ? breakoutDayPrev && latestClose > upperLatest && breakoutVolumeOkPrev
      : breakoutDayLatest && breakoutVolumeOkLatest
    const boxBreakdownConfirmed = confirmDays === 2
      ? breakdownDayPrev && latestClose < lowerLatest
      : prevClose >= lowerLatest && latestClose < lowerLatest
    const isTrendGateOpen = latestClose > ma250 && isMA250SlopeUp && isMA60SlopeUp && boxBreakoutConfirmed
    const crossDownMA20 = isCrossDown(prevClose, prevMA20, latestClose, ma20)
    const crossDownMA60 = isCrossDown(prevClose, prevMA60, latestClose, ma60)
    const crossDownMA90 = isCrossDown(prevClose, prevMA90, latestClose, ma90)
    const crossUpMA20 = isCrossUp(prevClose, prevMA20, latestClose, ma20)
    const crossUpMA60 = isCrossUp(prevClose, prevMA60, latestClose, ma60)
    const crossUpMA90 = isCrossUp(prevClose, prevMA90, latestClose, ma90)
    const crossUpMA250 = isCrossUp(prevClose, prevMA250, latestClose, ma250)

    const statusDownMA20 = isTrendGateOpen ? (crossDownMA20 ? '已触发(加仓20%)' : '未触发') : '暂停(未满足: 收盘>MA250 且 MA250/MA60斜率≥0 且 箱体上沿突破确认)'
    const statusDownMA60 = isTrendGateOpen ? (crossDownMA60 ? '已触发(加仓40%)' : '未触发') : '暂停(未满足: 收盘>MA250 且 MA250/MA60斜率≥0 且 箱体上沿突破确认)'
    const statusDownMA90 = isTrendGateOpen ? (crossDownMA90 ? '已触发(加仓剩余40%)' : '未触发') : '暂停(未满足: 收盘>MA250 且 MA250/MA60斜率≥0 且 箱体上沿突破确认)'
    const statusUpMA20 = crossUpMA20 ? '已触发(卖出20%)' : '未触发'
    const statusUpMA60 = crossUpMA60 ? '已触发(卖出40%)' : '未触发'
    const statusUpMA90 = crossUpMA90 ? '已触发(卖出剩余40%)' : '未触发'
    const statusTrend = ma10 > ma20 ? '已满足(上涨趋势)' : '未满足'
    const statusMA250 = isBelowMA250 ? '已触发(停止加仓/建议减仓)' : (crossUpMA250 ? '已触发(恢复加仓)' : '未触发')
    const statusBoxBreakout = boxBreakoutConfirmed ? '已确认(连续2日 + 突破日放量)' : '未确认'
    const statusBoxBreakdown = boxBreakdownConfirmed ? '已确认(连续2日)' : '未确认'
    const statusBoxRange = `上沿${upperLatest.toFixed(2)} / 下沿${lowerLatest.toFixed(2)} (N=${boxWindow})`
    const breakoutDate = confirmDays === 2
      ? (breakoutDayPrev ? klineData[prevIndex].date : '—')
      : (breakoutDayLatest ? klineData[latestIndex].date : '—')
    const breakoutConfirmDate = boxBreakoutConfirmed ? klineData[latestIndex].date : '—'
    const breakoutVolumeRatio = confirmDays === 2
      ? (Number.isFinite(prevVolumeMA) && prevVolumeMA > 0 ? prevVolume / prevVolumeMA : null)
      : (Number.isFinite(latestVolumeMA) && latestVolumeMA > 0 ? latestVolume / latestVolumeMA : null)
    const breakoutVolumeRatioText = Number.isFinite(breakoutVolumeRatio) ? `${breakoutVolumeRatio.toFixed(2)}x` : '—'
    const breakoutVolumeGateText = `${volumeExpandRatio.toFixed(2)}x`

    const htmlPayload = `
      <div class="zh299-wrap">
        <div class="zh299-price">价格：${latestClose.toFixed(2)} (${change >= 0 ? '+' : ''}${change.toFixed(2)} / ${changePercent.toFixed(2)}%)</div>
        <div class="zh299-grid">
          <div class="zh299-block">
            <div class="zh299-title">均线快照</div>
            <div class="zh299-row">MA10：${ma10.toFixed(2)} ｜ MA20：${ma20.toFixed(2)} ｜ MA60：${ma60.toFixed(2)}</div>
            <div class="zh299-row">MA90：${ma90.toFixed(2)} ｜ MA250：${ma250.toFixed(2)}</div>
            <div class="zh299-row">趋势：${trendText} ｜ 年线状态：${yearLineText}</div>
            <div class="zh299-row">箱体：${statusBoxRange}</div>
          </div>
          <div class="zh299-block">
            <div class="zh299-title">299执行面板</div>
            <div class="zh299-row">20日线跌破：${statusDownMA20} ｜ 站上：${statusUpMA20}</div>
            <div class="zh299-row">60日线跌破：${statusDownMA60} ｜ 站上：${statusUpMA60}</div>
            <div class="zh299-row">90日线跌破：${statusDownMA90} ｜ 站上：${statusUpMA90}</div>
            <div class="zh299-row">MA10＞MA20：${statusTrend} ｜ MA250：${statusMA250}</div>
            <div class="zh299-row">箱体上沿突破：${statusBoxBreakout}</div>
            <div class="zh299-row">突破日：${breakoutDate} ｜ 确认日：${breakoutConfirmDate}</div>
            <div class="zh299-row">突破日量比：${breakoutVolumeRatioText} ｜ 放量门槛：${breakoutVolumeGateText}</div>
            <div class="zh299-row">箱体下沿跌破：${statusBoxBreakdown}</div>
          </div>
        </div>
      </div>
    `

    const data = [{
      label: config.name,
      symbol: symbol,
      displaySymbol: sourceSymbol,
      isMaCard: true,
      render_type: 'zhonghang_299_html',
      html: htmlPayload,
      card_custom_class: config.card_custom_class || 'card-zhonghang-299',
      ma10: ma10.toFixed(2),
      ma20: ma20.toFixed(2),
      ma60: ma60.toFixed(2),
      ma90: ma90.toFixed(2),
      ma250: ma250.toFixed(2),
      source: config.source || 'tencent',
      name: config.name,
      price: latestClose,
      prevClose: prevClose,
      change: change,
      change_percent: changePercent,
      market_status: `${trendText} (${latestDate})`
    }]

    const alerts = buildAlerts({
      latestClose,
      prevClose,
      ma10,
      ma20,
      ma60,
      ma90,
      ma250,
      prevMA20,
      prevMA60,
      prevMA90,
      prevMA250,
      isTrendGateOpen,
      boxBreakoutConfirmed,
      boxBreakdownConfirmed
    })

    return { data, alerts }
  }
}