import { useRef, useState, type MouseEvent } from 'react'
import { api } from '@shared/api/client'
import type { SeriesDto } from '@shared/api/types'
import { fmtMs, fmtPct } from '@shared/format'
import { useQuery } from '@shared/hooks'

/** 总览卡片可以看的时长，以及每一格的长度（格数约 36～48，太多就挤了）。 */
export const OVERVIEW_RANGES = [
  { value: '3h', label: '近 3 小时', hours: 3, step: '5m', stepMin: 5 },
  { value: '6h', label: '近 6 小时', hours: 6, step: '10m', stepMin: 10 },
  { value: '12h', label: '近 12 小时', hours: 12, step: '15m', stepMin: 15 },
  { value: '24h', label: '近 24 小时', hours: 24, step: '30m', stepMin: 30 },
  { value: '48h', label: '近 48 小时', hours: 48, step: '1h', stepMin: 60 },
  { value: '96h', label: '近 96 小时', hours: 96, step: '2h', stepMin: 120 },
] as const

export type OverviewRange = (typeof OVERVIEW_RANGES)[number]['value']

type Level = 'ok' | 'warn' | 'bad' | 'none'

const levelOf = (loss: number | null | undefined): Level => (loss === null || loss === undefined ? 'none' : loss <= 0.5 ? 'ok' : loss < 3 ? 'warn' : 'bad')

const clock = (ms: number, showDate: boolean) => new Date(ms).toLocaleString('zh-CN', { ...(showDate ? { month: '2-digit', day: '2-digit' } : {}), hour: '2-digit', minute: '2-digit', hour12: false })

interface Props {
  lineId: string
  range: OverviewRange
  /** 所选时间范围的汇总（左上、右上的数字）。 */
  m: Record<string, number | null | undefined>
}

/** 一条线路的 QUIC/TCP 双行摘要，各自显示时延、质量点阵和丢包/重传率。 */
export function LineStrips({ lineId, range, m }: Props) {
  const info = OVERVIEW_RANGES.find((r) => r.value === range) ?? OVERVIEW_RANGES[0]
  const series = useQuery(
    () => api.get<SeriesDto>(`/api/public/lines/${encodeURIComponent(lineId)}/series`, { range: info.value, anchor: 'now', step: info.step, preset: 'quic,tcp', metrics: 'loss.up,loss.down,loss.total,rtt.p50,rtt.p95,rtt.p99,tcp.retrans,tcp.rtt.p50' }),
    [lineId, info.value],
    30_000,
  )
  const s = series.data
  const t = s?.t ?? []
  const col = (key: string): (number | null)[] => s?.values[key] ?? []
  // 悬停的那一格：QUIC 上下行和 TCP 共用时间轴。
  const [hover, setHover] = useState<number | null>(null)
  const last = useRef<number | null>(null) // 提示收回去的动画期间，内容还要留着
  if (hover !== null) last.current = hover
  const shown = hover ?? last.current
  // 整块线路区域都能触发：按鼠标横向位置对应到采样格，不用精确指到小格上。
  const box = useRef<HTMLDivElement>(null)
  const onMove = (e: MouseEvent<HTMLDivElement>) => {
    const bars = box.current?.querySelector('.bars')
    if (!s || t.length < 1 || !bars) return
    const r = bars.getBoundingClientRect()
    setHover(Math.min(t.length - 1, Math.max(0, Math.floor(((e.clientX - r.left) / r.width) * t.length))))
  }
  const common = { t, ready: Boolean(s), cells: Math.round((info.hours * 60) / info.stepMin), stepText: info.stepMin >= 60 ? `${info.stepMin / 60} 小时` : `${info.stepMin} 分钟`, hoursText: `${info.hours} 小时`, hover }
  const at = shown !== null && t[shown] !== undefined ? shown : null
  const lossUp = col('loss.up')
  const lossDown = col('loss.down')
  const retrans = col('tcp.retrans')
  const up = m['loss.up']
  const down = m['loss.down']
  const upText = up === null || up === undefined ? '丢包 —' : `${fmtPct(up)} 丢包`
  const downText = down === null || down === undefined ? '丢包 —' : `${fmtPct(down)} 丢包`
  const retransValue = m['tcp.retrans']
  const retransTone = levelOf(retransValue)
  const retransText = retransValue === null || retransValue === undefined ? '重传 —' : `${fmtPct(retransValue)} 重传`
  return (
    <div className="strips" ref={box} onMouseMove={onMove} onMouseLeave={() => setHover(null)}>
      <div className="line-mini-stack">
        <div className="line-mini-quic-head" title={`QUIC RTT p50 ${fmtMs(m['rtt.p50'])} · p95 ${fmtMs(m['rtt.p95'])} · p99 ${fmtMs(m['rtt.p99'])}`}>
          <span>QUIC</span><strong className="num">{fmtMs(m['rtt.p50'])}</strong><small>悬停看 p95 / p99</small>
          {series.error ? <span className="line-mini-badge bad" title={`上一次取数失败：${series.error.message}`}>数据未更新</span> : null}
        </div>
        <div className="line-mini-direction">
          <div className="line-mini-direction-head" title={`去程 Probe → Agent 丢包 ${fmtPct(up)}`}>
            <span>去程</span>
            <span className={`line-mini-badge ${levelOf(up)}`}>{upText}</span>
          </div>
          <div className="bars" role="img" aria-label={`近 ${common.hoursText}每 ${common.stepText}的去程丢包`}>
            {(s ? lossUp : Array.from({ length: common.cells }, () => null)).map((value, i) => (
              <span key={`up-${t[i] ?? i}`} className={`bar ${s ? levelOf(value) : 'none'}${hover === i ? ' on' : ''}`} />
            ))}
          </div>
        </div>
        <div className="line-mini-direction">
          <div className="line-mini-direction-head" title={`回程 Agent → Probe 丢包 ${fmtPct(down)}`}>
            <span>回程</span>
            <span className={`line-mini-badge ${levelOf(down)}`}>{downText}</span>
          </div>
          <div className="bars" role="img" aria-label={`近 ${common.hoursText}每 ${common.stepText}的回程丢包`}>
            {(s ? lossDown : Array.from({ length: common.cells }, () => null)).map((value, i) => (
              <span key={`down-${t[i] ?? i}`} className={`bar ${s ? levelOf(value) : 'none'}${hover === i ? ' on' : ''}`} />
            ))}
          </div>
        </div>
        <div className="line-mini-tcp">
          <div className="line-mini-tcp-head" title={`TCP RTT p50 ${fmtMs(m['tcp.rtt.p50'])}`}>
            <span>TCP</span><strong className="num">{fmtMs(m['tcp.rtt.p50'])}</strong>
            <span className={`line-mini-badge ${retransTone}`}>{retransText}</span>
          </div>
          <div className="bars" role="img" aria-label={`近 ${common.hoursText}每 ${common.stepText}的 TCP 重传`}>
            {(s ? retrans : Array.from({ length: common.cells }, () => null)).map((value, i) => (
              <span key={`retrans-${t[i] ?? i}`} className={`bar ${s ? levelOf(value) : 'none'}${hover === i ? ' on' : ''}`} />
            ))}
          </div>
        </div>
      </div>
      <div className={`pop num${hover !== null && at !== null ? ' open' : ''}`} role="tooltip" aria-hidden={hover === null}>
        {at !== null ? (
          <>
            <b className="pop-time">
              {clock(t[at], info.hours >= 24)}–{clock(t[at] + info.stepMin * 60_000, info.hours >= 24)}
            </b>
            <div className="pop-group">
              <span className="pop-name">QUIC Datagram</span>
              <span>RTT p50 <em>{fmtMs(col('rtt.p50')[at])}</em></span>
              <span>RTT p95 <em>{fmtMs(col('rtt.p95')[at])}</em></span>
              <span>RTT p99 <em>{fmtMs(col('rtt.p99')[at])}</em></span>
              <span>
                去程丢包 <em className={levelOf(col('loss.up')[at])}>{fmtPct(col('loss.up')[at])}</em>
              </span>
              <span>
                回程丢包 <em className={levelOf(col('loss.down')[at])}>{fmtPct(col('loss.down')[at])}</em>
              </span>
            </div>
            <div className="pop-group">
              <span className="pop-name">TCP</span>
              <span>
                重传 <em className={levelOf(col('tcp.retrans')[at])}>{fmtPct(col('tcp.retrans')[at])}</em>
              </span>
              <span>
                RTT p50 <em>{fmtMs(col('tcp.rtt.p50')[at])}</em>
              </span>
            </div>
          </>
        ) : null}
      </div>
    </div>
  )
}