import { useMemo, useState } from 'react'
import { useTranslation } from 'react-i18next'
import type { IngressSample, IngressRouteStats } from '../ingress-insights'
import { summarizeIngress } from '../ingress-insights'

type Mode = 'traffic' | 'errors' | 'slow' | 'detail'
type ErrorClass = 'all' | '5xx' | '4xx'
const modeIds: Mode[] = ['traffic', 'errors', 'slow', 'detail']
const modeLabelKeys: Record<Mode, string> = {
  traffic: 'ingress.modeTraffic',
  errors: 'ingress.modeErrors',
  slow: 'ingress.modeSlow',
  detail: 'ingress.modeDetail',
}
const heading = 'px-3 py-2 text-left font-medium whitespace-nowrap'
const cell = 'px-3 py-2 tabular-nums'
const formatSeconds = (seconds: number | null) => seconds === null ? '—' : `${seconds.toFixed(3)} s`
const routeKey = (route: IngressRouteStats) => `${route.domain}\u0000${route.path}`

function Route({ route }: { route: IngressRouteStats }) {
  return <><td className={`${cell} max-w-48 truncate`} title={route.domain}>{route.domain}</td>
    <td className={`${cell} max-w-96 truncate font-mono`} title={route.path}>{route.path}</td></>
}

export function IngressInsightsTable({ samples, loadedCount }: { samples: IngressSample[]; loadedCount: number }) {
  const { t } = useTranslation('logs')
  const [mode, setMode] = useState<Mode>('traffic')
  const [errorClass, setErrorClass] = useState<ErrorClass>('all')
  const [slowThreshold, setSlowThreshold] = useState(1)
  const summary = useMemo(() => summarizeIngress(samples, slowThreshold), [samples, slowThreshold])
  const traffic = useMemo(() => [...summary.routes].sort((a, b) => b.pv - a.pv || b.error5xx - a.error5xx).slice(0, 10), [summary.routes])
  const errors = useMemo(() => [...summary.routes]
    .filter(route => errorClass === '5xx' ? route.error5xx : errorClass === '4xx' ? route.error4xx : route.error4xx + route.error5xx)
    .sort((a, b) => {
      const count = (route: IngressRouteStats) => errorClass === '5xx' ? route.error5xx : errorClass === '4xx' ? route.error4xx : route.error4xx + route.error5xx
      return count(b) - count(a) || b.error5xx - a.error5xx
    }).slice(0, 10), [summary.routes, errorClass])
  const slow = useMemo(() => [...summary.routes].filter(route => route.slow || route.timeoutSignals)
    .sort((a, b) => b.slow - a.slow || b.timeoutSignals - a.timeoutSignals || (b.maxSeconds ?? 0) - (a.maxSeconds ?? 0)).slice(0, 10), [summary.routes])
  const modes = useMemo(() => modeIds.map(id => ({ id, label: t(modeLabelKeys[id]) })), [t])

  return <div className="space-y-3">
    <p className="text-xs text-muted-foreground">{t('ingress.summary', { loaded: loadedCount, parsed: samples.length })}</p>
    <div className="grid grid-cols-2 gap-2 sm:grid-cols-4">
      {[
        [t('ingress.statPv'), summary.pv], [t('ingress.statUv'), summary.uv], [t('ingress.statErrors'), summary.errors], [t('ingress.statSlow', { threshold: slowThreshold }), summary.slow],
      ].map(([label, value]) => <div key={label} className="rounded-lg border bg-muted/20 px-3 py-2"><div className="text-xs text-muted-foreground">{label}</div><div className="text-lg font-semibold tabular-nums">{value}</div></div>)}
    </div>
    <div className="flex flex-wrap items-center gap-2">
      <div role="tablist" aria-label={t('ingress.modesAria')} className="flex flex-wrap gap-1 rounded-md bg-muted/60 p-1">
        {modes.map(item => <button key={item.id} type="button" role="tab" aria-selected={mode === item.id} onClick={() => setMode(item.id)} className={`rounded px-2.5 py-1.5 text-xs ${mode === item.id ? 'bg-card font-medium shadow-sm' : 'text-muted-foreground hover:text-foreground'}`}>{item.label}</button>)}
      </div>
      {mode === 'errors' && <select aria-label={t('ingress.errorClassAria')} value={errorClass} onChange={event => setErrorClass(event.target.value as ErrorClass)} className="h-8 rounded border bg-background px-2 text-xs"><option value="all">{t('ingress.errorAll')}</option><option value="5xx">{t('ingress.error5xx')}</option><option value="4xx">{t('ingress.error4xx')}</option></select>}
      {mode === 'slow' && <label className="flex items-center gap-1 text-xs text-muted-foreground">{t('ingress.slowThreshold')} <select aria-label={t('ingress.slowThreshold')} value={slowThreshold} onChange={event => setSlowThreshold(Number(event.target.value))} className="h-8 rounded border bg-background px-2 text-foreground"><option value={0.5}>{t('ingress.seconds', { count: 0.5 })}</option><option value={1}>{t('ingress.seconds', { count: 1 })}</option><option value={3}>{t('ingress.seconds', { count: 3 })}</option><option value={5}>{t('ingress.seconds', { count: 5 })}</option><option value={10}>{t('ingress.seconds', { count: 10 })}</option></select></label>}
    </div>
    {mode === 'slow' && <p className="text-xs text-muted-foreground">{t('ingress.slowHint')}{summary.timed < summary.pv && ` ${t('ingress.slowMissing', { count: summary.pv - summary.timed })}`}</p>}
    {mode === 'traffic' && <p className="text-xs text-muted-foreground">{t('ingress.trafficHint')}</p>}
    <div className="max-h-[60vh] overflow-auto rounded-lg border">
      {mode === 'traffic' && <table className="w-full min-w-[680px] text-xs"><thead className="sticky top-0 bg-muted text-muted-foreground"><tr>{[t('ingress.thHost'), t('ingress.thPath'), 'PV', t('ingress.statUv'), t('ingress.thSuccess'), '4xx', '5xx'].map(title => <th key={title} className={heading}>{title}</th>)}</tr></thead><tbody className="divide-y">{traffic.map(route => <tr key={routeKey(route)} className="hover:bg-muted/40"><Route route={route} /><td className={cell}>{route.pv}</td><td className={cell}>{route.uv}</td><td className={cell}>{(route.success / route.pv * 100).toFixed(1)}%</td><td className={cell}>{route.error4xx}</td><td className={cell}>{route.error5xx}</td></tr>)}</tbody></table>}
      {mode === 'errors' && <table className="w-full min-w-[700px] text-xs"><thead className="sticky top-0 bg-muted text-muted-foreground"><tr>{[t('ingress.thHost'), t('ingress.thPath'), '4xx', '5xx', t('ingress.thErrorRate'), t('ingress.thStatus')].map(title => <th key={title} className={heading}>{title}</th>)}</tr></thead><tbody className="divide-y">{errors.map(route => <tr key={routeKey(route)} className="hover:bg-muted/40"><Route route={route} /><td className={cell}>{route.error4xx}</td><td className={cell}>{route.error5xx}</td><td className={cell}>{((route.error4xx + route.error5xx) / route.pv * 100).toFixed(1)}%</td><td className={cell}>{route.statusCodes}</td></tr>)}</tbody></table>}
      {mode === 'slow' && <table className="w-full min-w-[700px] text-xs"><thead className="sticky top-0 bg-muted text-muted-foreground"><tr>{[t('ingress.thHost'), t('ingress.thPath'), t('ingress.thSlow'), t('ingress.thMaxLatency'), t('ingress.thAvgLatency'), t('ingress.thTimeout')].map(title => <th key={title} className={heading}>{title}</th>)}</tr></thead><tbody className="divide-y">{slow.map(route => <tr key={routeKey(route)} className="hover:bg-muted/40"><Route route={route} /><td className={cell}>{route.slow}</td><td className={cell}>{formatSeconds(route.maxSeconds)}</td><td className={cell}>{formatSeconds(route.averageSeconds)}</td><td className={cell}>{route.timeoutSignals}</td></tr>)}</tbody></table>}
      {mode === 'detail' && <table className="w-full min-w-[800px] text-xs"><thead className="sticky top-0 bg-muted text-muted-foreground"><tr>{[t('ingress.thTime'), t('ingress.thHost'), t('ingress.thPath'), t('ingress.thClientIp'), t('ingress.thStatusShort'), t('ingress.thLatency')].map(title => <th key={title} className={heading}>{title}</th>)}</tr></thead><tbody className="divide-y">{samples.map(({ access, timestamp }, index) => <tr key={`${timestamp}-${index}`} className="hover:bg-muted/40"><td className={`${cell} whitespace-nowrap`}>{new Date(timestamp).toLocaleString()}</td><td className={`${cell} max-w-48 truncate`}>{access.domain || '—'}</td><td className={`${cell} max-w-96 truncate font-mono`} title={`${access.method} ${access.path}`}>{access.method} {access.path}</td><td className={cell}>{access.clientIp || '—'}</td><td className={cell}>{access.status}</td><td className={cell}>{access.requestTime ? `${access.requestTime} s` : '—'}</td></tr>)}</tbody></table>}
      {((mode === 'traffic' && !traffic.length) || (mode === 'errors' && !errors.length) || (mode === 'slow' && !slow.length)) && <p className="px-3 py-10 text-center text-sm text-muted-foreground">{t('ingress.empty')}</p>}
    </div>
  </div>
}