import { useCallback, useEffect, useState } from 'react'
import { Loading, ErrorState } from '../../../components/PageState.jsx'
import { dateTime } from '../../../lib/format.js'
import {
  freshnessOf, statusOf, gateLabelFor, describeRequest, leadershipOf, GATED_NOTE,
} from '../../../lib/teamAdmin.js'
import { useAuth } from '../../../contexts/AuthContext.jsx'
import { api } from '../../../api/client.js'
import TeamIntegrations from './TeamIntegrations.jsx'
import TeamVoice from './TeamVoice.jsx'

// Admin → Teams (docs/website/TEAMS.md §2.4, §2.8, §2.9).
//
// Three panels, in the order an operator needs them:
//
//   1. **Sync state**, verbatim, including the last error. The screen's first job
//      is to make "the shard has no Teams" and "core has not been able to ask for
//      two hours" impossible to confuse — they render almost identically
//      otherwise, and one is fine while the other is an outage.
//   2. **The review queue** — Teams auto-hidden because their name matched the
//      impersonation list, each showing which term matched.
//   3. **The approval queue** — what moderators have asked to publish.
//
// Everything that decides what a row SAYS lives in lib/teamAdmin.js, which is
// plain JS and has tests; this file renders it.

// Tones map onto the badge modifiers the rest of the admin panel already uses,
// rather than onto inline colours. `.badge` on its own carries no border or
// background — those live on the modifier — so a bare `className="badge"` with an
// inline `borderColor` renders borderless, which is what this screen used to do.
const TONE_BADGE = { ok: 'badge-pub', warn: 'badge-moderator', bad: 'badge-ban', idle: 'badge-draft' }

// The same three tones as text, for the places a badge would be wrong (a verbatim
// error line). House palette — the values every other admin view uses.
const TONE_TEXT = { ok: '#7fd0a4', warn: '#e0b070', bad: '#d98b84', idle: 'var(--muted)' }

const PANEL = { padding: 22, marginBottom: 22 }
const HEADING = { margin: '0 0 12px', fontSize: '1.2rem', color: 'var(--head)' }
const KV_VALUE = { margin: 0, fontSize: '0.88rem', color: 'var(--text)' }
const SCROLLER = { overflowX: 'auto' }
const BLURB = { margin: '0 0 14px', color: 'var(--muted)', fontSize: '0.85rem', lineHeight: 1.6 }

function Pill({ tone, children }) {
  return <span className={`badge ${TONE_BADGE[tone] || 'badge-draft'}`}>{children}</span>
}

// ── Sync state ─────────────────────────────────────────────────────────────

function SyncPanel({ sync, syncState, onResync, busy }) {
  const freshness = freshnessOf(sync)
  return (
    <section className="panel" style={PANEL}>
      <div style={{ display: 'flex', alignItems: 'center', gap: 12, flexWrap: 'wrap', marginBottom: 12 }}>
        <h2 className="display" style={{ ...HEADING, margin: 0 }}>Sync</h2>
        <Pill tone={freshness.tone}>{freshness.label}</Pill>
        <button
          type="button"
          className="btn btn-ghost btn-sq"
          onClick={onResync}
          disabled={busy || !sync.configured}
        >
          {busy ? 'Resyncing…' : 'Resync now'}
        </button>
      </div>
      <p className="sans" style={{ margin: 0, color: 'var(--muted)', fontSize: '0.85rem' }}>{freshness.detail}</p>

      {syncState && (
        <dl
          style={{
            display: 'grid', gridTemplateColumns: 'auto minmax(0, 1fr)', gap: '9px 20px',
            margin: '16px 0 0', alignItems: 'baseline',
          }}
        >
          <dt className="field-label" style={{ margin: 0 }}>Module</dt>
          <dd className="sans" style={KV_VALUE}>{syncState.moduleId}</dd>
          <dt className="field-label" style={{ margin: 0 }}>Last attempt</dt>
          <dd className="sans" style={KV_VALUE}>{dateTime(syncState.lastAttemptAt) || 'never'}</dd>
          <dt className="field-label" style={{ margin: 0 }}>Last success</dt>
          <dd className="sans" style={KV_VALUE}>{dateTime(syncState.lastSuccessAt) || 'never'}</dd>
          <dt className="field-label" style={{ margin: 0 }}>Consecutive failures</dt>
          <dd className="sans" style={KV_VALUE}>{syncState.consecutiveFailures}</dd>
          {syncState.lastError && (
            <>
              {/* Verbatim. An operator debugging a stale projection needs what the
                  provider actually said, not a friendlier paraphrase of it. */}
              <dt className="field-label" style={{ margin: 0 }}>Last error</dt>
              <dd className="sans" style={{ ...KV_VALUE, color: TONE_TEXT.bad }}>{syncState.lastError}</dd>
            </>
          )}
          {syncState.pendingEmptySince && (
            <>
              <dt className="field-label" style={{ margin: 0 }}>Empty answer held</dt>
              <dd className="sans" style={KV_VALUE}>
                since {dateTime(syncState.pendingEmptySince)} — an authoritative but empty list is
                applied only if the next answer agrees.
              </dd>
            </>
          )}
        </dl>
      )}
    </section>
  )
}

// ── The reserved-name review queue ─────────────────────────────────────────

function ReviewQueue({ rows, role, onAct, busy }) {
  if (!rows.length) return null
  return (
    <section className="panel" style={PANEL}>
      <h2 className="display" style={HEADING}>Names to review</h2>
      <p className="sans" style={BLURB}>
        These Teams are hidden from every public surface because their name matched a reserved term.
        They work normally for their own members. {GATED_NOTE}
      </p>
      <div className="panel-flat" style={SCROLLER}>
        <table className="adm-table">
          <thead>
            <tr>
              <th className="adm-th">Name</th>
              <th className="adm-th">Matched</th>
              <th className="adm-th">Members</th>
              <th className="adm-th">Created</th>
              <th className="adm-th" />
            </tr>
          </thead>
          <tbody>
            {rows.map((row) => (
              <tr key={row.id}>
                <td className="adm-td" style={{ color: 'var(--head)' }}>{row.name}</td>
                <td className="adm-td"><Pill tone="bad">{row.hidden_term}</Pill></td>
                <td className="adm-td">{row.member_count}</td>
                <td className="adm-td dim">{dateTime(row.created_at)}</td>
                <td className="adm-td" style={{ textAlign: 'right' }}>
                  <button
                    type="button"
                    className="btn btn-primary btn-sq"
                    disabled={busy}
                    onClick={() => onAct(row.id, 'unhide')}
                  >
                    {gateLabelFor(role, 'Publish')}
                  </button>
                </td>
              </tr>
            ))}
          </tbody>
        </table>
      </div>
    </section>
  )
}

// ── The approval queue ─────────────────────────────────────────────────────

function RequestQueue({ rows, role, onDecide, busy }) {
  if (!rows.length) return null
  const canDecide = role === 'admin'
  return (
    <section className="panel" style={PANEL}>
      <h2 className="display" style={HEADING}>Awaiting approval</h2>
      <p className="sans" style={BLURB}>
        {canDecide
          ? 'Approving publishes the name; rejecting keeps the record and changes nothing.'
          : 'Only an admin can decide these. Your own requests stay here until one does.'}
      </p>
      <div className="panel-flat" style={SCROLLER}>
        <table className="adm-table">
          <thead>
            <tr>
              <th className="adm-th">Request</th>
              <th className="adm-th">Requested</th>
              <th className="adm-th">Reason</th>
              {canDecide && <th className="adm-th" />}
            </tr>
          </thead>
          <tbody>
            {rows.map((row) => (
              <tr key={row.id}>
                <td className="adm-td" style={{ color: 'var(--head)' }}>{describeRequest(row)}</td>
                <td className="adm-td dim">{dateTime(row.requested_at)}</td>
                <td className="adm-td dim">{row.reason ? `“${row.reason}”` : '—'}</td>
                {canDecide && (
                  <td className="adm-td" style={{ textAlign: 'right', whiteSpace: 'nowrap' }}>
                    <button
                      type="button"
                      className="btn btn-primary btn-sq"
                      disabled={busy}
                      onClick={() => onDecide(row.id, 'approved')}
                    >
                      Approve
                    </button>
                    <button
                      type="button"
                      className="btn btn-ghost btn-sq"
                      style={{ marginLeft: 8 }}
                      disabled={busy}
                      onClick={() => onDecide(row.id, 'rejected')}
                    >
                      Reject
                    </button>
                  </td>
                )}
              </tr>
            ))}
          </tbody>
        </table>
      </div>
    </section>
  )
}

// ── One Team ───────────────────────────────────────────────────────────────

function TeamRow({ team, role, onAct, busy, onLedger }) {
  const status = statusOf(team)
  return (
    <tr>
      <td className="adm-td" style={{ color: 'var(--head)' }}>
        {team.displayName}
        {team.displayNameOverride && (
          <div className="dim" style={{ fontSize: '0.78rem', marginTop: 3 }}>
            shown instead of “{team.name}”
          </div>
        )}
      </td>
      <td className="adm-td"><Pill tone={status.tone}>{status.label}</Pill></td>
      <td className="adm-td">{team.memberCount}</td>
      <td className="adm-td">{team.linkedCount}</td>
      <td className="adm-td">{team.onlineCount}</td>
      <td className="adm-td dim">{dateTime(team.rosterSyncedAt) || 'never'}</td>
      <td className="adm-td" style={{ textAlign: 'right', whiteSpace: 'nowrap' }}>
        {team.status === 'active' && (team.hidden
          ? (
            <button
              type="button"
              className="btn btn-primary btn-sq"
              disabled={busy}
              onClick={() => onAct(team.id, 'unhide')}
            >
              {gateLabelFor(role, 'Publish')}
            </button>
          )
          : (
            <button
              type="button"
              className="btn btn-ghost btn-sq"
              disabled={busy}
              onClick={() => onAct(team.id, 'hide')}
            >
              Hide
            </button>
          ))}
        <button
          type="button"
          className="btn btn-ghost btn-sq"
          onClick={() => onLedger(team)}
          style={{ marginLeft: 8 }}
        >
          Forum log
        </button>
      </td>
    </tr>
  )
}

/**
 * One Team's forum moderation ledger (TEAMS.md §5.3).
 *
 * The route and the API method have existed since phase 4 and nothing rendered
 * them, which made the ledger a table only a DB client could read. The column
 * that earns the screen is `actorRole`: it records WHICH authority was exercised,
 * so a leader's ordinary housekeeping stays distinguishable from a staff
 * intervention after the fact.
 *
 * **This is deliberately not merged with the site's mod_actions/appeals pair.**
 * That one is Discord-sanction-shaped and bot-owned; routing a guild leader
 * locking a thread through it would make ordinary housekeeping an appealable
 * sanction with a reversal path into the bot. Every STAFF-exercised action here
 * additionally writes activity_log, so the site's accountability trail sees it —
 * the two are cross-referenced, not merged.
 */
function ForumLedger({ team, onClose }) {
  const [rows, setRows] = useState(null)
  const [error, setError] = useState('')

  useEffect(() => {
    let active = true
    api.admin.teamForumModeration(team.id)
      // `{ entries }`, and the rows are the ledger table's own snake_case
      // columns — this endpoint serves them unmapped, unlike the Team payloads
      // above it. Reading them as they are, rather than accepting three possible
      // shapes, is what makes a change to that endpoint fail here instead of
      // rendering an empty table.
      .then((res) => { if (active) setRows(res.entries) })
      .catch((err) => { if (active) setError(err.message || 'Could not load the forum log.') })
    return () => { active = false }
  }, [team.id])

  return (
    <section className="panel" style={PANEL}>
      <header
        style={{
          display: 'flex', justifyContent: 'space-between', alignItems: 'center',
          gap: 14, flexWrap: 'wrap', marginBottom: 12,
        }}
      >
        <h2 className="display" style={{ ...HEADING, margin: 0 }}>Forum log — {team.displayName}</h2>
        <button type="button" className="btn btn-ghost btn-sq" onClick={onClose}>Close</button>
      </header>
      {error && <ErrorState message={error} />}
      {!rows && !error && <Loading />}
      {rows && rows.length === 0 && (
        <p className="sans" style={{ ...BLURB, margin: 0 }}>Nothing has been moderated in this forum.</p>
      )}
      {rows && rows.length > 0 && (
        <div className="panel-flat" style={SCROLLER}>
          <table className="adm-table">
            <thead>
              <tr>
                <th className="adm-th">When</th>
                <th className="adm-th">Action</th>
                <th className="adm-th">Target</th>
                <th className="adm-th">By</th>
                <th className="adm-th">As</th>
                <th className="adm-th">Reason</th>
              </tr>
            </thead>
            <tbody>
              {rows.map((r) => (
                <tr key={r.id}>
                  <td className="adm-td dim">{dateTime(r.created_at)}</td>
                  <td className="adm-td" style={{ color: 'var(--head)' }}>{r.action}</td>
                  <td className="adm-td dim">{r.target_type} #{r.target_id}</td>
                  <td className="adm-td">{r.actor_username || '—'}</td>
                  <td className="adm-td">
                    {/* The distinction the whole ledger exists to preserve. */}
                    <Pill tone={r.actor_role === 'staff' ? 'warn' : 'ok'}>{r.actor_role}</Pill>
                  </td>
                  <td className="adm-td dim">{r.reason || '—'}</td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      )}
    </section>
  )
}

// ── The screen ─────────────────────────────────────────────────────────────

export default function TeamsAdmin() {
  const { user } = useAuth()
  const role = user ? user.role : null

  const [data, setData] = useState(null)
  const [review, setReview] = useState([])
  const [requests, setRequests] = useState([])
  const [error, setError] = useState('')
  const [notice, setNotice] = useState('')
  const [busy, setBusy] = useState(false)
  const [ledgerTeam, setLedgerTeam] = useState(null)

  const load = useCallback(async () => {
    setError('')
    try {
      const [teams, reviewQueue, requestQueue] = await Promise.all([
        api.admin.listTeams(),
        api.admin.teamReviewQueue(),
        api.admin.teamRequests('pending'),
      ])
      setData(teams)
      setReview(reviewQueue.teams || [])
      setRequests(requestQueue.requests || [])
    } catch (err) {
      setError(err.message || 'Could not load Teams.')
    }
  }, [])

  useEffect(() => { load() }, [load])

  async function run(fn, pendingMessage) {
    setBusy(true)
    setNotice('')
    setError('')
    try {
      const result = await fn()
      // The server decides whether an action applied or was filed, from the
      // caller's live role. Saying so plainly is what stops a moderator thinking
      // nothing happened.
      if (result && result.pending) setNotice(pendingMessage)
      await load()
    } catch (err) {
      setError(err.message || 'That did not work.')
    } finally {
      setBusy(false)
    }
  }

  const act = (id, action) => run(
    () => (action === 'hide' ? api.admin.hideTeam(id) : api.admin.unhideTeam(id)),
    'Filed for approval. Nothing has changed publicly until an admin approves it.',
  )

  const decide = (id, status) => run(
    () => api.admin.decideTeamRequest(id, status),
    '',
  )

  const resync = () => run(async () => {
    const result = await api.admin.resyncTeams()
    // A refusal is the normal, designed outcome when the provider cannot answer,
    // so it is reported as a result rather than thrown as an error.
    if (!result.ok) setError(`Resync refused: ${result.reason}. Nothing was changed.`)
    else if (result.quarantined) {
      setNotice('The provider answered with an empty list. It is being held for confirmation, not applied.')
    }
    return null
  }, '')

  if (error && !data) return <ErrorState message={error} />
  if (!data) return <Loading />

  return (
    <div>
      {/* No page <h1>: AdminLayout's topbar already titles the page, as it does for
          every other admin screen. This one used to render its own, which is why
          "Teams" appeared twice — once in Cinzel in the bar and once in the body
          in whatever the UA picked for an unstyled heading. */}
      {error && <ErrorState message={error} />}
      {notice && (
        <div className="note sans" style={{ fontSize: '0.85rem', marginBottom: 22 }}>{notice}</div>
      )}

      {ledgerTeam && <ForumLedger team={ledgerTeam} onClose={() => setLedgerTeam(null)} />}

      {/* Admin-only, matching the server (§7.2). Rendered for a moderator it would
          be a panel every action in fails 403 — the role gate is the server's, and
          this is only how the screen agrees with it. */}
      {role === 'admin' && <TeamIntegrations />}
      {role === 'admin' && <TeamVoice />}

      <SyncPanel sync={data} syncState={data.syncState} onResync={resync} busy={busy} />
      <ReviewQueue rows={review} role={role} onAct={act} busy={busy} />
      <RequestQueue rows={requests} role={role} onDecide={decide} busy={busy} />

      <section className="panel" style={PANEL}>
        <h2 className="display" style={HEADING}>All Teams</h2>
        {!data.teams.length && (
          <p className="sans" style={{ ...BLURB, margin: 0 }}>
            {data.configured
              ? 'No Teams in the projection yet.'
              : 'No installed module supplies Teams, so there is nothing to show.'}
          </p>
        )}
        {data.teams.length > 0 && (
          <div className="panel-flat" style={SCROLLER}>
            <table className="adm-table">
              <thead>
                <tr>
                  <th className="adm-th">Name</th>
                  <th className="adm-th">Status</th>
                  <th className="adm-th">Members</th>
                  <th className="adm-th">Linked</th>
                  <th className="adm-th">Online</th>
                  <th className="adm-th">Roster confirmed</th>
                  <th className="adm-th" />
                </tr>
              </thead>
              <tbody>
                {data.teams.map((team) => (
                  <TeamRow
                    key={team.id}
                    team={team}
                    role={role}
                    onAct={act}
                    busy={busy}
                    onLedger={setLedgerTeam}
                  />
                ))}
              </tbody>
            </table>
          </div>
        )}
      </section>
    </div>
  )
}

export { leadershipOf }