const TOOLS = [
  { value: 'list_files', label: 'List Files', description: 'Lists files and directories in a given path.', params: [{ name: 'path', type: 'text', label: 'Directory Path' }] },
  { value: 'read_file', label: 'Read File', description: 'Reads the content of a specific file.', params: [{ name: 'path', type: 'text', label: 'File Path' }] },
  { value: 'create_file', label: 'Create File', description: 'Creates a new file with optional content.', params: [{ name: 'path', type: 'text', label: 'New File Path' }, { name: 'content', type: 'textarea', label: 'Initial Content (optional)' }] },
  { value: 'write_file', label: 'Write to File', description: 'Writes content to a file, creating a backup first.', params: [{ name: 'path', type: 'text', label: 'File Path' }, { name: 'content', type: 'textarea', label: 'New Content' }] },
  { value: 'delete_file', label: 'Delete File', description: 'Deletes a specific file.', params: [{ name: 'path', type: 'text', label: 'File to Delete' }] },
  { value: 'identify_log_errors', label: 'Identify Log Errors', description: 'Scans a log file for common error messages.', params: [{ name: 'log_file_path', type: 'text', label: 'Log File Path' }] },
];

function App() {
  const [selectedTool, setSelectedTool] = React.useState(TOOLS[0].value);
  const [parameters, setParameters] = React.useState({ path: 'C:\\temp' });
  const [isLoading, setIsLoading] = React.useState(false);
  const [response, setResponse] = React.useState(null);
  const [error, setError] = React.useState('');

  const currentTool = React.useMemo(() => TOOLS.find(t => t.value === selectedTool), [selectedTool]);

  const handleToolChange = (e) => {
    const newToolName = e.target.value;
    setSelectedTool(newToolName);
    setParameters({});
    setResponse(null);
    setError('');
  };

  const handleParamChange = (name, value) => {
    setParameters(prev => ({ ...prev, [name]: value }));
  };

  const handleSubmit = async (e) => {
    e.preventDefault();
    setIsLoading(true);
    setResponse(null);
    setError('');

    const invocation_id = `mcp-ui-${Date.now()}`;
    const endpoint = `http://127.0.0.1:8000/mcp/invoke/${selectedTool}`;

    try {
      const res = await fetch(endpoint, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          tool_name: selectedTool,
          invocation_id,
          parameters,
        }),
      });

      const data = await res.json();
      if (!res.ok || data.result?.status === 'error') {
        throw new Error(data.result?.message || `Server responded with status: ${res.status}`);
      }
      setResponse(data);
    } catch (err) {
      setError(err instanceof Error ? err.message : 'An unknown error occurred.');
    } finally {
      setIsLoading(false);
    }
  };

  return (
    <div className="container">
      <header>
        <h1>MCP Toolkit Control Panel</h1>
        <p>A client to interact with the Maintenance & Control Program toolkit server.</p>
      </header>
      
      <main>
        <div className="card form-card">
          <h2>Select a Tool</h2>
          <form onSubmit={handleSubmit}>
            <div className="form-group">
              <label htmlFor="tool-select">Tool</label>
              <select id="tool-select" value={selectedTool} onChange={handleToolChange}>
                {TOOLS.map(tool => (
                  <option key={tool.value} value={tool.value}>{tool.label}</option>
                ))}
              </select>
              <p>{currentTool.description}</p>
            </div>
            
            {currentTool.params.map(param => (
              <div className="form-group" key={param.name}>
                <label htmlFor={param.name}>{param.label}</label>
                {param.type === 'textarea' ? (
                  <textarea
                    id={param.name}
                    value={parameters[param.name] || ''}
                    onChange={(e) => handleParamChange(param.name, e.target.value)}
                    required
                  />
                ) : (
                  <input
                    id={param.name}
                    type="text"
                    value={parameters[param.name] || ''}
                    onChange={(e) => handleParamChange(param.name, e.target.value)}
                    required
                  />
                )}
              </div>
            ))}

            <button type="submit" disabled={isLoading}>
              {isLoading ? 'Running...' : `Run: ${currentTool.label}`}
            </button>
          </form>
        </div>

        {isLoading && (
          <div className="card status-card">
            <div className="loader">
                <span></span>
                <span></span>
                <span></span>
            </div>
            <p>Communicating with MCP Server...</p>
          </div>
        )}

        {error && (
          <div className="card result-card error">
            <h2>Error</h2>
            <pre>{error}</pre>
          </div>
        )}

        {response && (
          <div className="card result-card success">
            <h2>Result for Invocation: {response.invocation_id}</h2>
            <pre>{JSON.stringify(response.result, null, 2)}</pre>
          </div>
        )}
      </main>
    </div>
  );
}

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<App />);