import { useCallback, useEffect, useMemo, useState } from 'react'
import { useParams, Link } from 'react-router-dom'
import { Loading, ErrorState } from '../../../components/PageState.jsx'
import { useAsync } from '../../../lib/useAsync.js'
import { dateTime, ago } from '../../../lib/format.js'
import { api } from '../../../api/client.js'
import CharacterStats from '../../../components/CharacterStats.jsx'
import GameAccounts from '../../../components/GameAccounts.jsx'
import VendorSales from '../../../components/VendorSales.jsx'

// Admin read-only view of one user's shard (uo-link) footprint: linked game
// accounts + character rosters, currently-online characters, houses (incl.
// IDOC) and recent vendor sales — everything scoped to that user's accounts.
// Reached from the Users table's "View" action; Edit stays a separate modal.

const ROLE_BADGE = {
  admin: 'badge-admin',
  editor: 'badge-editor',
  moderator: 'badge-moderator',
  player: 'badge-player',
}

function SectionTitle({ children }) {
  return (
    <div className="field-label" style={{ marginBottom: 12, marginTop: 4 }}>
      {children}
    </div>
  )
}

// Currently-online characters on the user's accounts, with where they are. The
// per-character Online/Offline badge lives in the roster; this adds location.
function OnlineNow({ scope }) {
  const { data } = useAsync(() => scope.online(), [scope])
  if (!data) return null
  return (
    <section style={{ borderTop: '1px solid var(--line-soft)', marginTop: 30, paddingTop: 22 }}>
      <SectionTitle>Online now</SectionTitle>
      {data.length === 0 ? (
        <p className="sans dim" style={{ margin: 0, fontSize: '0.86rem' }}>No characters online right now.</p>
      ) : (
        <ul style={{ listStyle: 'none', margin: 0, padding: 0, display: 'flex', flexDirection: 'column', gap: 8 }}>
          {data.map((c) => (
            <li key={c.serial} className="sans" style={{ display: 'flex', justifyContent: 'space-between', gap: 12, fontSize: '0.9rem', color: 'var(--ink)' }}>
              <span style={{ display: 'inline-flex', alignItems: 'center', gap: 8, minWidth: 0 }}>
                <span style={{ width: 8, height: 8, borderRadius: '50%', background: '#7fd0a4', boxShadow: '0 0 6px #7fd0a4', flex: 'none' }} />
                <span style={{ color: 'var(--head)' }}>{c.name || '(unnamed)'}</span>
              </span>
              <span className="dim" style={{ flex: 'none', fontSize: '0.8rem' }}>
                {c.map != null ? `map ${c.map} · ${c.x}, ${c.y}` : '—'}
              </span>
            </li>
          ))}
        </ul>
      )}
    </section>
  )
}

// Shard "standing": city governorships held and guilds led by this user's
// accounts (both reliable current-state lookups). Renders nothing when empty.
function Standing({ scope }) {
  const { data } = useAsync(() => scope.standing(), [scope])
  if (!data) return null
  const govs = data.governorOf || []
  const guilds = data.guildsLed || []
  if (govs.length === 0 && guilds.length === 0) return null
  return (
    <section style={{ borderTop: '1px solid var(--line-soft)', marginTop: 30, paddingTop: 22 }}>
      <SectionTitle>Standing</SectionTitle>
      <div style={{ display: 'flex', flexWrap: 'wrap', gap: 8 }}>
        {govs.map((g) => (
          <span key={`gov-${g.city}`} className="sans" style={{ fontSize: '0.78rem', padding: '4px 10px', borderRadius: 999, border: '1px solid #c9a24b55', color: '#c9a24b' }}>
            Governor of {g.city}
          </span>
        ))}
        {guilds.map((g) => (
          <span key={`guild-${g.id}`} className="sans" style={{ fontSize: '0.78rem', padding: '4px 10px', borderRadius: 999, border: '1px solid var(--accent)', color: 'var(--accent)' }}>
            Guildmaster{g.abbr ? `, [${g.abbr}]` : ''} {g.name}
          </span>
        ))}
      </div>
    </section>
  )
}

// One house row — the many optional detail fields are gathered here so the
// Houses list stays a simple map.
function HouseRow({ house: h }) {
  const location = h.region || (h.map != null ? `map ${h.map}` : 'unknown')
  const coords = h.x != null ? ` · ${h.x}, ${h.y}` : ''
  const owner = h.ownerAcct ? ` · ${h.ownerAcct}` : ''
  const shares = h.coOwners || h.friends ? ` · ${h.coOwners || 0} co-owners, ${h.friends || 0} friends` : ''
  return (
    <li
      style={{ display: 'flex', justifyContent: 'space-between', gap: 12, alignItems: 'baseline', padding: '12px 14px', border: '1px solid var(--line)', borderRadius: 10, background: 'rgba(255,255,255,0.02)' }}
    >
      <div style={{ minWidth: 0 }}>
        <div className="sans" style={{ color: 'var(--head)', fontSize: '0.95rem' }}>
          {h.name || 'Unnamed house'}
          {h.isIdoc && <span className="badge" style={{ marginLeft: 8, background: '#5b2020', color: '#f0c8c2' }}>IDOC</span>}
        </div>
        <div className="sans dim" style={{ fontSize: '0.78rem', marginTop: 2 }}>
          {location}
          {coords}
          {owner}
          {shares}
        </div>
      </div>
      <div className="sans dim" style={{ flex: 'none', fontSize: '0.78rem', textAlign: 'right' }}>
        {(h.decay || h.stage) ? <div style={{ color: h.isIdoc ? '#e0928a' : 'var(--muted)' }}>{h.decay || h.stage}</div> : null}
        {h.price != null ? <div style={{ fontVariantNumeric: 'tabular-nums' }}>{Number(h.price).toLocaleString()} gp</div> : null}
        {h.lastRefreshed ? <div>refreshed {ago(h.lastRefreshed)}</div> : null}
      </div>
    </li>
  )
}

// Houses owned by the user's accounts, IDOC first (flagged).
function Houses({ scope }) {
  const { data } = useAsync(() => scope.houses(), [scope])
  if (!data) return null
  return (
    <section style={{ borderTop: '1px solid var(--line-soft)', marginTop: 30, paddingTop: 22 }}>
      <SectionTitle>Houses</SectionTitle>
      {data.length === 0 ? (
        <p className="sans dim" style={{ margin: 0, fontSize: '0.86rem' }}>No houses recorded for this user’s accounts.</p>
      ) : (
        <ul style={{ listStyle: 'none', margin: 0, padding: 0, display: 'flex', flexDirection: 'column', gap: 10 }}>
          {data.map((h) => (
            <HouseRow key={h.serial} house={h} />
          ))}
        </ul>
      )}
    </section>
  )
}

// Admin security controls for one user: their trusted devices (view + revoke) and
// an MFA reset for a locked-out user. Every action is audit-logged server-side.
function SecurityAdmin({ userId }) {
  const [devices, setDevices] = useState(null)
  const [error, setError] = useState('')
  const [busy, setBusy] = useState(false)
  const [msg, setMsg] = useState('')

  const load = useCallback(async () => {
    try {
      setDevices(await api.admin.userTrustedDevices(userId))
    } catch {
      setError('Could not load trusted devices.')
    }
  }, [userId])
  useEffect(() => {
    load()
  }, [load])

  async function revoke(deviceId) {
    setBusy(true); setMsg(''); setError('')
    try {
      await api.admin.revokeUserTrustedDevice(userId, deviceId)
      await load()
    } catch {
      setError('Could not revoke that device.')
    } finally {
      setBusy(false)
    }
  }

  async function revokeAll() {
    if (!window.confirm('Revoke ALL of this user’s trusted devices?')) return
    setBusy(true); setMsg(''); setError('')
    try {
      await api.admin.revokeAllUserTrustedDevices(userId)
      setMsg('All trusted devices revoked.')
      await load()
    } catch {
      setError('Could not revoke devices.')
    } finally {
      setBusy(false)
    }
  }

  async function resetMfa() {
    if (!window.confirm('Reset this user’s two-factor? This turns TOTP off, revokes their trusted devices, and clears their recovery codes so they can sign in with their password.')) return
    setBusy(true); setMsg(''); setError('')
    try {
      await api.admin.resetUserMfa(userId)
      setMsg('Two-factor has been reset for this user.')
      await load()
    } catch {
      setError('Could not reset two-factor.')
    } finally {
      setBusy(false)
    }
  }

  const fmt = (d) => {
    const t = d ? new Date(d) : null
    return t && !Number.isNaN(t.getTime()) ? t.toLocaleDateString() : '—'
  }

  return (
    <section style={{ borderTop: '1px solid var(--line-soft)', marginTop: 30, paddingTop: 22 }}>
      <SectionTitle>Security &amp; two-factor</SectionTitle>
      {devices == null ? (
        <p className="sans dim" style={{ margin: 0, fontSize: '0.86rem' }}>Loading…</p>
      ) : devices.length === 0 ? (
        <p className="sans dim" style={{ margin: 0, fontSize: '0.86rem' }}>No trusted devices.</p>
      ) : (
        <ul style={{ listStyle: 'none', margin: '0 0 14px', padding: 0, display: 'flex', flexDirection: 'column', gap: 8 }}>
          {devices.map((d) => (
            <li key={d.id} style={{ display: 'flex', alignItems: 'center', gap: 12, padding: '10px 14px', border: '1px solid var(--line)', borderRadius: 8 }}>
              <div style={{ flex: 1, minWidth: 0 }}>
                <div className="sans" style={{ color: 'var(--head)', fontSize: '0.9rem' }}>
                  {d.deviceName || (d.platform === 'mobile' ? 'Mobile app' : 'Browser')}
                </div>
                <div className="sans dim" style={{ fontSize: '0.76rem', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>
                  {d.userAgent || '—'} · last used {fmt(d.lastUsedAt)} · expires {fmt(d.expiresAt)}
                </div>
              </div>
              <button onClick={() => revoke(d.id)} disabled={busy} className="pill" style={{ color: '#d98b84', borderColor: '#d98b84' }}>
                Revoke
              </button>
            </li>
          ))}
        </ul>
      )}

      <div style={{ display: 'flex', gap: 10, alignItems: 'center', flexWrap: 'wrap' }}>
        {devices && devices.length > 0 && (
          <button onClick={revokeAll} disabled={busy} className="pill" style={{ color: '#d98b84', borderColor: '#d98b84' }}>
            Revoke all trusted devices
          </button>
        )}
        <button onClick={resetMfa} disabled={busy} className="btn btn-sq" style={{ borderColor: '#d98b84', color: '#d98b84' }}>
          Reset two-factor
        </button>
      </div>

      {msg && <p className="sans" style={{ marginTop: 12, color: '#7fd0a4', fontSize: '0.86rem' }}>{msg}</p>}
      {error && <p className="sans" style={{ marginTop: 12, color: '#d98b84', fontSize: '0.86rem' }}>{error}</p>}
    </section>
  )
}

function ShardSections({ scope }) {
  return (
    <>
      <CharacterStats scope={scope} />
      <SectionTitle>Linked accounts &amp; characters</SectionTitle>
      <GameAccounts scope={scope} readOnly moderation onUnlink={scope.unlink} charTo={(serial) => `/admin/characters/${serial}`} />
      <Standing scope={scope} />
      <OnlineNow scope={scope} />
      <Houses scope={scope} />
      <VendorSales fetchSales={scope.sales} />
    </>
  )
}

export default function UserDetail() {
  const { id } = useParams()
  // Memoize so the child components' effects (keyed on `scope`) don't refetch
  // on every render.
  const scope = useMemo(() => api.admin.userShard(id), [id])
  const { loading, error, data: user } = useAsync(() => api.admin.getUser(id), [id])

  if (loading) return <Loading />
  if (error) return <ErrorState message="Could not load this user." />

  return (
    <section>
      <Link to="/admin/users" className="link-accent" style={{ fontSize: '0.85rem' }}>
        ← Back to users
      </Link>

      {/* Header */}
      <div style={{ padding: 22, border: '1px solid var(--line)', borderRadius: 12, background: 'var(--panel-grad)', margin: '12px 0 24px' }}>
        <div style={{ display: 'flex', alignItems: 'baseline', gap: 12, flexWrap: 'wrap' }}>
          <span className="display" style={{ fontSize: '1.5rem', color: 'var(--head)' }}>
            {user.username}
          </span>
          <span className={`badge ${ROLE_BADGE[user.role] || 'badge-editor'}`}>{user.role}</span>
          <span
            className="sans"
            style={{ fontSize: '0.82rem', color: user.status && user.status !== 'active' ? '#d98b84' : 'var(--muted)' }}
          >
            {user.status || 'active'}
          </span>
        </div>
        <div className="sans dim" style={{ display: 'flex', gap: 18, marginTop: 10, flexWrap: 'wrap', fontSize: '0.8rem' }}>
          {user.email && <span>{user.email}</span>}
          <span>Last login: {user.last_login_at ? dateTime(user.last_login_at) : 'never'}</span>
          {user.created_at && <span>Joined: {dateTime(user.created_at)}</span>}
        </div>
      </div>

      <SecurityAdmin userId={id} />
      <ShardSections scope={scope} />
    </section>
  )
}