import React from 'react';

type WorkflowRuntime = {
  mode?: string;
};

const LOCAL_WORKFLOW_URL = '/workflow-ui/';
const DOCKER_WORKFLOW_URL = '/api/comfyui/proxy/';

export default function Workflows() {
  const [ready, setReady] = React.useState(false);
  const [loading, setLoading] = React.useState(true);
  const [message, setMessage] = React.useState('正在加载工作流前端...');
  const [workflowUrl, setWorkflowUrl] = React.useState(LOCAL_WORKFLOW_URL);
  const [backendLabel, setBackendLabel] = React.useState('');
  const [reloadKey, setReloadKey] = React.useState(0);
  const iframeRef = React.useRef<HTMLIFrameElement | null>(null);

  const openFullscreen = () => {
    window.open(workflowUrl, '_blank', 'noopener,noreferrer');
  };

  const reloadFrame = () => {
    if (iframeRef.current) {
      setLoading(true);
      iframeRef.current.src = workflowUrl;
      return;
    }
    setLoading(true);
    setMessage('正在重新检查工作流入口...');
    setReloadKey((value) => value + 1);
  };

  React.useEffect(() => {
    let cancelled = false;
    const controller = new AbortController();
    const loadRuntime = async () => {
      const runtimeResponse = await fetch('/api/workflow-ui/runtime', { signal: controller.signal });
      const runtime = runtimeResponse.ok ? ((await runtimeResponse.json()) as WorkflowRuntime) : {};
      const dockerMode = runtime.mode === 'docker';
      const targetUrl = dockerMode ? DOCKER_WORKFLOW_URL : LOCAL_WORKFLOW_URL;
      if (cancelled) return;
      setBackendLabel(resolveBackendLabel(runtime.mode));
      setWorkflowUrl(targetUrl);
      const response = await fetch(targetUrl, { signal: controller.signal });
      if (cancelled) return;
      setReady(response.ok);
      setLoading(false);
      setMessage(response.ok ? '' : 'Workflow Studio 前端未构建，请先执行 workflow-ui:install');
    };
    void loadRuntime().catch((error) => {
      if (cancelled || error?.name === 'AbortError') return;
      setReady(false);
      setLoading(false);
      setMessage('工作流入口不可用，请检查服务配置');
    });
    return () => {
      cancelled = true;
      controller.abort();
    };
  }, [reloadKey]);

  return (
    <div className="workflow-shell">
      <div className="workflow-toolbar">
        <div className="workflow-toolbar-main">
          <div className="workflow-title">工作流</div>
          {backendLabel && <div className="workflow-backend-badge">{backendLabel}</div>}
        </div>
        <div className="workflow-actions">
          <button type="button" onClick={reloadFrame} disabled={!ready} className="btn btn-link workflow-action-btn">
            刷新
          </button>
          <button type="button" onClick={openFullscreen} className="btn btn-primary workflow-primary-btn">
            新窗口打开
          </button>
        </div>
      </div>
      {ready ? (
        <div className="workflow-frame-wrap">
          {loading && (
            <div className="workflow-frame-loading" aria-live="polite">
              <div className="workflow-loading-bar" />
              <span>正在连接工作流前端...</span>
            </div>
          )}
          <iframe
            ref={iframeRef}
            src={workflowUrl}
            title="Workflow Studio"
            allow="clipboard-read; clipboard-write"
            referrerPolicy="no-referrer"
            onLoad={() => setLoading(false)}
            className="workflow-frame"
          />
        </div>
      ) : (
        <div className="workflow-empty">
          <div className="workflow-empty-panel">
            <div className="workflow-empty-title">Workflow Studio</div>
            <div className="workflow-empty-desc">{message}</div>
            <button type="button" onClick={reloadFrame} className="btn btn-soft-primary workflow-empty-btn">
              重新检查
            </button>
          </div>
        </div>
      )}
    </div>
  );
}

function resolveBackendLabel(mode?: string) {
  switch (mode) {
    case 'cloud':
      return 'Comfy Cloud API 后端';
    case 'runninghub':
      return 'RunningHub API 后端';
    case 'external':
      return '外部 ComfyUI API 后端';
    case 'docker':
      return 'Docker 完整版 ComfyUI';
    case 'boosapi':
      return 'BoosAPI 工作流执行器';
    default:
      return '';
  }
}