'use client';

import { useEffect, useRef } from 'react';
import Link from 'next/link';
import SiteNav from '../components/SiteNav';

const API_BASE = process.env.NEXT_PUBLIC_API_BASE ?? 'https://cypher.arcrun.dev';

export default function ApiDocsPage() {
  const containerRef = useRef<HTMLDivElement>(null);
  const initialized = useRef(false);

  useEffect(() => {
    if (initialized.current || !containerRef.current) return;
    initialized.current = true;

    // Dynamically load Swagger UI from CDN
    const link = document.createElement('link');
    link.rel = 'stylesheet';
    link.href = 'https://unpkg.com/swagger-ui-dist@5/swagger-ui.css';
    document.head.appendChild(link);

    const script = document.createElement('script');
    script.src = 'https://unpkg.com/swagger-ui-dist@5/swagger-ui-bundle.js';
    script.onload = () => {
      const SwaggerUIBundle = (window as unknown as { SwaggerUIBundle: (opts: unknown) => void }).SwaggerUIBundle;
      if (!SwaggerUIBundle || !containerRef.current) return;
      SwaggerUIBundle({
        url: `${API_BASE}/openapi.json`,
        dom_id: '#swagger-ui',
        presets: [(window as unknown as { SwaggerUIBundle: { presets: { apis: unknown } } }).SwaggerUIBundle.presets.apis],
        layout: 'BaseLayout',
        defaultModelsExpandDepth: -1,
        docExpansion: 'list',
        filter: true,
        tryItOutEnabled: true,
        supportedSubmitMethods: ['get', 'post', 'put', 'delete', 'patch'],
        requestInterceptor: (request: { headers: Record<string, string> }) => {
          // Inject API key from localStorage if present
          const key = localStorage.getItem('arcrun_api_key');
          if (key) request.headers['X-Arcrun-API-Key'] = key;
          return request;
        },
      });
    };
    document.head.appendChild(script);

    return () => {
      // cleanup not strictly needed for page navigation
    };
  }, []);

  return (
    <div className="min-h-screen bg-[#0a0a0a] text-[#ededed]">
      <SiteNav currentPath="/api-docs" />

      {/* Header */}
      <div className="max-w-5xl mx-auto px-6 py-8">
        <h1 className="text-2xl font-bold text-white mb-2">API Reference</h1>
        <p className="text-[#555] text-sm mb-2">
          這是 arcrun 的原始 API。Python / JS lib 是它的包裝，任何能發 HTTP request 的工具都能直接用。
        </p>
        <p className="text-[#444] text-xs mb-6">
          Endpoint: <span className="font-mono text-[#666]">{API_BASE}</span>
        </p>

        {/* API Key hint */}
        <div className="bg-[#111] border border-[#222] rounded-lg p-4 mb-8 text-sm">
          <p className="text-[#666] mb-2">
            若要在此頁面試打 API，請先設定 API Key：
          </p>
          <ApiKeyInput />
        </div>

        {/* Swagger UI */}
        <div className="bg-white rounded-xl overflow-hidden" ref={containerRef}>
          <div id="swagger-ui" className="min-h-96"></div>
        </div>
      </div>
    </div>
  );
}

function ApiKeyInput() {
  return (
    <div className="flex gap-2">
      <input
        type="text"
        placeholder="ak_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
        className="flex-1 bg-[#0a0a0a] border border-[#2a2a2a] rounded px-3 py-1.5 text-xs font-mono text-[#cdd6f4] focus:outline-none focus:border-indigo-700"
        onChange={(e) => {
          if (e.target.value.startsWith('ak_')) {
            localStorage.setItem('arcrun_api_key', e.target.value);
          }
        }}
      />
      <span className="text-[#444] text-xs self-center">自動注入到 requests</span>
    </div>
  );
}