import { useEffect, useState } from 'react'
import { RefreshCw, KeyRound, Ban, Trash2, Copy, Download } from 'lucide-react'
import { fetchTerminals, createTerminal, revokeTerminal, deleteTerminal, extensionDownloadUrl } from '../api'
import type { Terminal } from '../types'

export default function Terminals() {
  const [terminals, setTerminals] = useState<Terminal[]>([])
  const [loading, setLoading] = useState(true)
  const [error, setError] = useState('')
  const [newName, setNewName] = useState('')
  const [creating, setCreating] = useState(false)
  const [revealedKey, setRevealedKey] = useState<{ name: string; key: string } | null>(null)

  function load() {
    setLoading(true)
    fetchTerminals()
      .then(setTerminals)
      .catch(e => setError(e instanceof Error ? e.message : 'Failed to load terminals'))
      .finally(() => setLoading(false))
  }

  useEffect(load, [])

  async function handleCreate(e: React.FormEvent) {
    e.preventDefault()
    if (!newName.trim()) return
    setCreating(true); setError('')
    try {
      const t = await createTerminal(newName.trim())
      setRevealedKey({ name: t.name, key: t.api_key })
      setNewName('')
      load()
    } catch (e) {
      setError(e instanceof Error ? e.message : 'Create failed')
    } finally {
      setCreating(false)
    }
  }

  async function handleRevoke(id: string) {
    if (!confirm('Revoke this terminal key? The Chrome extension using it will stop working immediately.')) return
    try {
      await revokeTerminal(id)
      load()
    } catch (e) {
      setError(e instanceof Error ? e.message : 'Revoke failed')
    }
  }

  async function handleDelete(id: string) {
    if (!confirm('Delete this terminal permanently?')) return
    try {
      await deleteTerminal(id)
      load()
    } catch (e) {
      setError(e instanceof Error ? e.message : 'Delete failed')
    }
  }

  return (
    <div className="page">
      <div className="page-header">
        <h1>Terminals</h1>
        <button className="btn" onClick={load}><RefreshCw size={14} strokeWidth={1.75} /> Refresh</button>
      </div>
      <p className="field-hint" style={{ marginBottom: 14 }}>
        API keys for the standalone "Send to Check-in Tablet" Chrome extension — one per reception PC.
        The extension calls this app's push endpoint using a terminal key instead of a staff login
        (hotel-owned hardware gets a device credential, same trust tier as the tablets themselves).
      </p>

      <div className="card" style={{ marginBottom: 20 }}>
        <div style={{ fontWeight: 600, marginBottom: 6 }}>Chrome Extension</div>
        <p className="field-hint" style={{ marginBottom: 10 }}>
          Not published anywhere yet, so it needs installing manually on each reception PC: download,
          unzip, then <code>chrome://extensions</code> → enable Developer mode → Load unpacked →
          select the unzipped folder. It'll need a terminal key from below to actually authorize
          pushes — create one first if you haven't already.
        </p>
        <a className="btn" href={extensionDownloadUrl()} style={{ display: 'inline-flex', alignItems: 'center', gap: 6, textDecoration: 'none' }}>
          <Download size={16} strokeWidth={1.75} /> Download Extension (.zip)
        </a>
      </div>

      {error && <div className="error-banner">{error}</div>}

      {revealedKey && (
        <div className="card" style={{ borderColor: 'var(--gold)', marginBottom: 16 }}>
          <div style={{ fontWeight: 600, marginBottom: 6 }}>
            <KeyRound size={14} strokeWidth={1.75} style={{ verticalAlign: '-2px' }} /> Key for "{revealedKey.name}"
          </div>
          <p className="field-hint" style={{ marginBottom: 8 }}>
            Copy this now and paste it into the extension's settings popup — it will never be shown again.
          </p>
          <div style={{ display: 'flex', gap: 8, alignItems: 'center' }}>
            <code style={{ flex: 1, wordBreak: 'break-all', fontSize: 12, background: 'var(--body-bg)', padding: '6px 8px', borderRadius: 6 }}>
              {revealedKey.key}
            </code>
            <button className="btn btn-sm" onClick={() => navigator.clipboard.writeText(revealedKey.key)}>
              <Copy size={12} strokeWidth={1.75} /> Copy
            </button>
          </div>
          <button className="btn btn-sm" style={{ marginTop: 10 }} onClick={() => setRevealedKey(null)}>Done</button>
        </div>
      )}

      <form onSubmit={handleCreate} style={{ display: 'flex', gap: 8, marginBottom: 20 }}>
        <input
          type="text" placeholder="e.g. Reception PC 1" value={newName}
          onChange={e => setNewName(e.target.value)}
          style={{ flex: 1, border: '1px solid var(--card-border)', borderRadius: 8, padding: '8px 10px' }}
        />
        <button className="btn btn-primary" type="submit" disabled={creating}>
          {creating ? 'Creating…' : 'Create Terminal'}
        </button>
      </form>

      {loading ? <p className="muted">Loading…</p> : terminals.length === 0 ? (
        <div className="empty-state">No terminals yet.</div>
      ) : (
        <div className="table-wrap">
          <table className="data">
            <thead><tr><th>Name</th><th>Created</th><th>Last Used</th><th>Status</th><th></th></tr></thead>
            <tbody>
              {terminals.map(t => (
                <tr key={t.terminal_id}>
                  <td>{t.name}</td>
                  <td>{new Date(t.created_at).toLocaleDateString('en-GB')}</td>
                  <td>{t.last_used_at ? new Date(t.last_used_at).toLocaleString('en-GB') : 'never'}</td>
                  <td>
                    {t.revoked_at
                      ? <span className="badge badge-health-unresponsive">Revoked</span>
                      : <span className="badge badge-health-healthy">Active</span>}
                  </td>
                  <td style={{ display: 'flex', gap: 6 }}>
                    {!t.revoked_at && (
                      <button className="btn btn-sm" onClick={() => handleRevoke(t.terminal_id)}>
                        <Ban size={12} strokeWidth={1.75} /> Revoke
                      </button>
                    )}
                    <button className="btn btn-sm btn-danger" onClick={() => handleDelete(t.terminal_id)}>
                      <Trash2 size={12} strokeWidth={1.75} />
                    </button>
                  </td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      )}
    </div>
  )
}