import { useCallback, useEffect, useState } from 'react'
import { api } from '../../../api/client.js'
import {
  stateLabel, enableBlockedReason, roleHeadroom, removalCountdown,
  parseStaffRoles, formatStaffRoles, statusSummary,
} from '../../../lib/teamVoice.js'

// Team voice channels (TEAMS.md §7.3, phase 9).
//
// Named for the Team concern and placed under Teams beside the notification
// bridge, for the reason that panel gives: phase 10 replaces "Discord" with
// whatever the capability registry declares, and what should change then is what
// fills this panel rather than where an operator goes to find it.
//
// **The preflight is the first thing on the page, not a diagnostic.** §7.3
// assumed the bot could manage channels and roles; nothing in this project has
// ever checked, because the operator invites the bot by hand and no invite URL
// with a permission integer exists anywhere in the tree. An operator whose bot
// lacks Manage Roles otherwise has a screen full of controls that cannot work,
// and finds out one Team at a time from a column of identical errors.

const PANEL = { padding: 22, marginBottom: 22, maxWidth: 760 }
const HEADING = { margin: '0 0 6px', fontSize: '1.2rem', color: 'var(--head)' }

export default function TeamVoice() {
  const [config, setConfig] = useState(null)
  const [draft, setDraft] = useState(null)
  const [error, setError] = useState('')
  const [notice, setNotice] = useState('')
  const [busy, setBusy] = useState(false)

  const load = useCallback(async () => {
    setError('')
    try {
      const cfg = await api.admin.teamVoice()
      setConfig(cfg)
      setDraft({
        enabled: cfg.settings.enabled,
        minMembers: cfg.settings.minMembers,
        graceDays: cfg.settings.graceDays,
        staffRoles: formatStaffRoles(cfg.settings.staffRoles),
      })
    } catch (err) {
      // A moderator never reaches this panel — the admin nav does not render it —
      // so a 403 means the role changed underneath an open tab.
      setError(err.status === 403
        ? 'Only an admin can configure Team voice channels.'
        : (err.message || 'Could not load the voice configuration.'))
    }
  }, [])

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

  if (!config || !draft) {
    return (
      <section className="panel" style={PANEL}>
        <h2 className="display" style={HEADING}>Voice channels</h2>
        {error && <p className="sans" style={{ color: '#d98b84', fontSize: '0.82rem' }}>{error}</p>}
      </section>
    )
  }

  const blocked = enableBlockedReason(config.preflight)
  const headroom = roleHeadroom(config.preflight)

  async function save() {
    const { roles, invalid } = parseStaffRoles(draft.staffRoles)
    if (invalid.length > 0) {
      setError(`Not a role id: ${invalid.join(', ')}. Copy role ids from Discord with Developer Mode on.`)
      return
    }
    setBusy(true)
    setError('')
    setNotice('')
    try {
      await api.admin.saveTeamVoice({
        enabled: draft.enabled,
        minMembers: Number(draft.minMembers),
        graceDays: Number(draft.graceDays),
        staffRoles: roles,
      })
      setNotice('Saved.')
      await load()
    } catch (err) {
      setError(err.message || 'Could not save.')
    } finally {
      setBusy(false)
    }
  }

  async function runPass() {
    setBusy(true)
    setError('')
    setNotice('')
    try {
      const result = await api.admin.teamVoicePass()
      // A pass that refused says why, and that is the useful answer far more often
      // than a count is — "stale projection" and "synced 0" look identical in a
      // summary and mean completely different things.
      setNotice(result.ran
        ? `Synced ${result.synced}, created ${result.created}, scheduled ${result.scheduled}, removed ${result.removed}, failed ${result.failed}.`
        : `Nothing was done: ${result.reason}`)
      await load()
    } catch (err) {
      setError(err.message || 'Could not run a pass.')
    } finally {
      setBusy(false)
    }
  }

  async function remove(row) {
    setBusy(true)
    setError('')
    try {
      await api.admin.removeTeamVoice(row.teamId)
      setNotice('Removed.')
      await load()
    } catch (err) {
      setError(err.message || 'Could not remove.')
    } finally {
      setBusy(false)
    }
  }

  return (
    <section className="panel" style={PANEL}>
      <h2 className="display" style={HEADING}>Voice channels</h2>
      <p className="sans dim" style={{ fontSize: '0.78rem', margin: '0 0 14px' }}>
        Give each Team a {config.platform} voice channel of its own. Access is granted with a role per
        Team, so members of a Team can see and join their channel and nobody else can. Members need a
        linked {config.platform} account and must be in the guild.
      </p>

      {blocked && (
        <p className="sans" style={{ color: '#e0b070', fontSize: '0.82rem' }}>
          {blocked} Voice channels cannot be switched on until that is fixed.
        </p>
      )}

      {headroom && (
        <p className="sans dim" style={{ fontSize: '0.78rem' }}>
          {headroom.used} of {headroom.cap} {config.platform} roles used in this guild
          {headroom.exhausted
            ? ' — no room for another Team.'
            : headroom.tight
              ? ` — room for about ${headroom.free} more Teams.`
              : '.'}
        </p>
      )}

      {error && <p className="sans" style={{ color: '#d98b84', fontSize: '0.82rem' }}>{error}</p>}
      {notice && <p className="sans" style={{ color: '#7fd0a4', fontSize: '0.82rem' }}>{notice}</p>}

      <p className="sans" style={{ fontSize: '0.8rem' }}>{statusSummary(config.settings, config.rows)}</p>

      <div style={{ marginTop: 14, borderTop: '1px solid var(--line-soft)', paddingTop: 16 }}>
        <label className="sans" style={{ display: 'block', marginBottom: 12, fontSize: '0.82rem' }}>
          <input
            type="checkbox"
            checked={draft.enabled}
            disabled={busy || (!!blocked && !draft.enabled)}
            onChange={(e) => setDraft({ ...draft, enabled: e.target.checked })}
          />
          {' '}Provision voice channels for Teams
        </label>

        <label style={{ display: 'block', marginBottom: 12 }}>
          <span className="field-label">Minimum members</span>
          <input
            className="input"
            type="number"
            min="1"
            max="10000"
            value={draft.minMembers}
            disabled={busy}
            onChange={(e) => setDraft({ ...draft, minMembers: e.target.value })}
          />
          <span className="sans dim" style={{ display: 'block', fontSize: '0.74rem' }}>
            Every active member counts, whether or not they have linked an account.
          </span>
        </label>

        <label style={{ display: 'block', marginBottom: 12 }}>
          <span className="field-label">Grace window (days)</span>
          <input
            className="input"
            type="number"
            min="0"
            max="90"
            value={draft.graceDays}
            disabled={busy}
            onChange={(e) => setDraft({ ...draft, graceDays: e.target.value })}
          />
          <span className="sans dim" style={{ display: 'block', fontSize: '0.74rem' }}>
            How long a Team keeps its channel after it stops qualifying. A Team that recovers inside the
            window keeps the same channel; zero removes it on the next pass.
          </span>
        </label>

        <label style={{ display: 'block', marginBottom: 12 }}>
          <span className="field-label">Staff roles</span>
          <input
            className="input"
            type="text"
            value={draft.staffRoles}
            disabled={busy}
            placeholder="role id, role id"
            onChange={(e) => setDraft({ ...draft, staffRoles: e.target.value })}
          />
          <span className="sans dim" style={{ display: 'block', fontSize: '0.74rem' }}>
            Roles that can see and join every Team’s channel. Guild administrators already can, so this
            is for staff who are not administrators. Leave empty if there are none.
          </span>
        </label>

        <div style={{ display: 'flex', gap: 10, flexWrap: 'wrap' }}>
          <button type="button" className="btn btn-primary btn-sq" disabled={busy} onClick={save}>Save</button>
          <button type="button" className="btn btn-ghost btn-sq" disabled={busy} onClick={runPass}>Sync now</button>
        </div>
      </div>

      {config.rows.length > 0 && (
        <div className="panel-flat" style={{ marginTop: 18, overflowX: 'auto' }}>
          <table className="adm-table">
            <thead>
              <tr>
                <th className="adm-th">Team</th>
                <th className="adm-th">Members</th>
                <th className="adm-th">Channel</th>
                <th className="adm-th">State</th>
                <th className="adm-th" />
              </tr>
            </thead>
            <tbody>
              {config.rows.map((row) => (
                <tr key={row.teamId}>
                  <td className="adm-td" style={{ color: 'var(--head)' }}>{row.teamName}</td>
                  <td className="adm-td">{row.memberCount}</td>
                  <td className="adm-td dim">
                    {row.channelRef || <span className="dim">none</span>}
                  </td>
                  <td className="adm-td">
                    {stateLabel(row.state)}
                    {removalCountdown(row) && (
                      <span className="dim" style={{ display: 'block', fontSize: '0.78rem', marginTop: 3 }}>
                        {removalCountdown(row)}
                      </span>
                    )}
                    {row.lastError && (
                      <span style={{ display: 'block', color: '#d98b84', fontSize: '0.78rem', marginTop: 3 }}>
                        {row.lastError}
                      </span>
                    )}
                  </td>
                  <td className="adm-td" style={{ textAlign: 'right' }}>
                    <button type="button" className="btn btn-ghost btn-sq" disabled={busy} onClick={() => remove(row)}>Remove</button>
                  </td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      )}

      {config.lastPass && config.lastPass.at && (
        <p className="sans dim" style={{ fontSize: '0.74rem', marginTop: 10 }}>
          Last pass {new Date(config.lastPass.at).toLocaleString()}
          {config.lastPass.ran ? '' : ` — nothing was done: ${config.lastPass.reason}`}
        </p>
      )}
    </section>
  )
}