import { useEffect, useRef, useState } from 'react';
import { AnchorButton, Button, Callout, Intent, NonIdealState, Spinner, Tab, Tabs, Tag } from '@blueprintjs/core';
import DeployWizard from '../components/wizard/DeployWizard';
import { tenantUrl, CLARITY_DOMAIN } from '../config';
import { getTenants, subscribeToTenantLogs } from '../api/tenantApi';
import type { TenantRecord } from '../types/provisioning';

const ENV_INTENT: Record<string, Intent> = {
  prod: Intent.DANGER,
  uat:  Intent.WARNING,
  fdev: Intent.PRIMARY,
};

function TenantCard({ t }: { t: TenantRecord }) {
  const [logs, setLogs]         = useState<string[]>([]);
  const [logsOpen, setLogsOpen] = useState(false);
  const logRef                  = useRef<HTMLDivElement>(null);
  const sourceRef               = useRef<EventSource | null>(null);

  useEffect(() => {
    if (!logsOpen) return;
    const src = subscribeToTenantLogs(
      t.subdomain,
      (line) => setLogs((prev) => [...prev.slice(-500), line]),  // cap at 500 lines
      () => {}
    );
    sourceRef.current = src;
    return () => { src.close(); sourceRef.current = null; };
  }, [logsOpen, t.subdomain]);

  // Auto-scroll to bottom when new lines arrive
  useEffect(() => {
    if (logRef.current) logRef.current.scrollTop = logRef.current.scrollHeight;
  }, [logs]);

  return (
    <div className="job-card">
      <div className="job-card-header">
        <div>
          <strong>{t.clientName}</strong>
          <span className="job-card-subdomain">{t.subdomain}</span>
        </div>
        <div style={{ display: 'flex', gap: '0.4rem', alignItems: 'center' }}>
          <Tag intent={ENV_INTENT[t.environment] ?? Intent.NONE} round minimal>{t.environment}</Tag>
          <Tag intent={t.status === 'Provisioned' ? Intent.SUCCESS : Intent.WARNING} round>{t.status}</Tag>
        </div>
      </div>

      <Tabs onChange={(id) => setLogsOpen(id === 'logs')}>
        <Tab id="info" title="Info" panel={
          <div className="job-card-meta" style={{ paddingTop: '0.5rem' }}>
            <span>Site: <code>{t.siteCode}</code></span>
            <span>Container: <code>{t.containerName ?? '—'}{t.containerPort ? `:${t.containerPort}` : ''}</code></span>
            <span>{new Date(t.provisionedAt).toLocaleString()}</span>
            {t.status === 'Provisioned' && (
              <AnchorButton
                icon="share"
                minimal
                small
                href={tenantUrl(t.subdomain)}
                target="_blank"
                rel="noopener noreferrer"
                style={{ marginTop: '0.25rem' }}
              >
                {t.subdomain}.{CLARITY_DOMAIN}
              </AnchorButton>
            )}
          </div>
        } />
        <Tab id="logs" title="Server" panel={
          <div
            ref={logRef}
            style={{
              fontFamily:      'monospace',
              fontSize:        '0.75rem',
              background:      '#1a1a1a',
              color:           '#d4d4d4',
              padding:         '0.5rem',
              borderRadius:    '4px',
              height:          '260px',
              overflowY:       'auto',
              whiteSpace:      'pre-wrap',
              wordBreak:       'break-all',
              marginTop:       '0.5rem',
            }}
          >
            {logs.length === 0
              ? <span style={{ color: '#666' }}>Connecting to container logs…</span>
              : logs.map((l, i) => <div key={i}>{l}</div>)
            }
          </div>
        } />
      </Tabs>
    </div>
  );
}

export default function DashboardPage() {
  const [wizardOpen, setWizardOpen] = useState(false);
  const [tenants, setTenants]       = useState<TenantRecord[]>([]);
  const [loading, setLoading]       = useState(true);
  const [error, setError]           = useState<string | null>(null);

  const load = () => {
    getTenants()
      .then((data) => { setTenants(data); setError(null); })
      .catch((e: Error) => setError(e.message))
      .finally(() => setLoading(false));
  };

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

  const handleWizardClose = () => { setWizardOpen(false); setLoading(true); load(); };

  if (wizardOpen) return <DeployWizard onClose={handleWizardClose} />;

  return (
    <>
      <div className="page-header">
        <div>
          <h1>Provisioned Tenants</h1>
          <p>Manage and monitor client deployments.</p>
        </div>
        <div style={{ display: 'flex', gap: '0.5rem', alignItems: 'center' }}>
          <Button icon="refresh" minimal onClick={load} loading={loading} title="Refresh" />
          <Button intent={Intent.PRIMARY} text="Deploy New Client" icon="plus" large onClick={() => setWizardOpen(true)} />
        </div>
      </div>

      {loading && <NonIdealState icon={<Spinner />} title="Loading tenants..." />}

      {error && (
        <Callout intent={Intent.DANGER} title="Failed to load tenants" style={{ marginBottom: '1rem' }}>
          {error}
        </Callout>
      )}

      {!loading && !error && tenants.length === 0 && (
        <div className="empty-state">
          <div className="empty-state-icon">🏗️</div>
          <h3>No tenants provisioned yet</h3>
          <p>Deploy your first client to get started.</p>
          <Button intent={Intent.PRIMARY} text="Deploy New Client" icon="plus" onClick={() => setWizardOpen(true)} />
        </div>
      )}

      {!loading && tenants.length > 0 && (
        <div className="job-list">
            {tenants.map((t) => (
              <TenantCard key={t.subdomain} t={t} />
            ))}
        </div>
      )}
    </>
  );
}