KnowledgeBase/web/services/apiClient.ts

import { API_BASE_URL } from '../utils/constants';

interface ApiResponse<T = any> {
  data: T;
  status: number;
}

class ApiClient {
  private baseURL: string;

  constructor(baseURL: string) {
    this.baseURL = baseURL;
  }

  private getAuthHeaders(): Record<string, string> {
    const apiKey = localStorage.getItem('kb_api_key');
    const activeTenantId = localStorage.getItem('kb_active_tenant_id');
    const token = localStorage.getItem('authToken') || localStorage.getItem('token');
    const language = localStorage.getItem('userLanguage') || 'zh';

    const headers: Record<string, string> = {
      'Content-Type': 'application/json',
      'x-user-language': language,
    };

    if (apiKey) {
      if (apiKey.startsWith('kb_')) {
        headers['x-api-key'] = apiKey;
      } else {
        headers['Authorization'] = `Bearer ${apiKey}`;
      }
    } else if (token) {
      headers['Authorization'] = `Bearer ${token}`;
    }

    if (activeTenantId && activeTenantId !== 'undefined' && activeTenantId !== 'null') {
      headers['x-tenant-id'] = activeTenantId;
    }

    return headers;
  }

  private async handleResponse<T>(response: Response): Promise<ApiResponse<T>> {
    const text = await response.text();
    let data: any;
    try {
      data = text ? JSON.parse(text) : null;
    } catch (e) {
      data = null;
    }

    if (!response.ok) {
      throw new Error(data?.message || text || 'Request failed');
    }

    return { data: data as T, status: response.status };
  }

  // 新しい API 呼び出し方法、{ data, status } を返す
  async get<T = any>(url: string): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'GET',
      headers: this.getAuthHeaders(),
    });

    return this.handleResponse<T>(response);
  }

  async post<T = any>(url: string, body?: any): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'POST',
      headers: this.getAuthHeaders(),
      body: body ? JSON.stringify(body) : undefined,
    });

    return this.handleResponse<T>(response);
  }

  async put<T = any>(url: string, body?: any): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'PUT',
      headers: this.getAuthHeaders(),
      body: body ? JSON.stringify(body) : undefined,
    });

    return this.handleResponse<T>(response);
  }

  async patch<T = any>(url: string, body?: any): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'PATCH',
      headers: this.getAuthHeaders(),
      body: body ? JSON.stringify(body) : undefined,
    });

    return this.handleResponse<T>(response);
  }

  async delete<T = any>(url: string): Promise<ApiResponse<T>> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'DELETE',
      headers: this.getAuthHeaders(),
    });

    return this.handleResponse<T>(response);
  }
  
  // New methods for special formats
  async getBlob(url: string): Promise<Blob> {
    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'GET',
      headers: this.getAuthHeaders(),
    });

    if (!response.ok) {
      throw new Error('Request failed');
    }

    return await response.blob();
  }

  async postMultipart<T = any>(url: string, formData: FormData): Promise<ApiResponse<T>> {
    const headers = this.getAuthHeaders();
    // Remove Content-Type to let the browser set it with the correct boundary
    delete headers['Content-Type'];

    const response = await fetch(`${this.baseURL}${url}`, {
      method: 'POST',
      headers,
      body: formData,
    });

    return this.handleResponse<T>(response);
  }
  
  // Legacy compatibility method — returns raw Response for streaming and other special cases
  async request(path: string, options: RequestInit = {}): Promise<Response> {
    const authHeaders = this.getAuthHeaders();
    const headers = new Headers(options.headers);
    
    // Merge auth headers into request headers
    Object.entries(authHeaders).forEach(([key, value]) => {
      headers.set(key, value);
    });

    let url = path;
    if (!path.startsWith('http')) {
      const cleanPath = path.startsWith('/') ? path : `/${path}`;
      url = `${this.baseURL}${cleanPath}`;
    }

    const response = await fetch(url, {
      ...options,
      headers,
    });

    if (response.status === 401) {
      localStorage.removeItem('kb_api_key');
      localStorage.removeItem('authToken');
      window.location.href = '/login';
      throw new Error('Unauthorized');
    }

    return response;
  }

  private handleUnauthorized() {
    console.warn('[ApiClient] 401 Unauthorized detected. Cleaning up and redirecting to login...');
    localStorage.removeItem('kb_api_key');
    localStorage.removeItem('authToken');
    localStorage.removeItem('token');
    localStorage.removeItem('kb_active_tenant_id');
    // Only redirect if we are not already on the login page
    if (window.location.pathname !== '/login') {
        window.location.href = '/login';
    }
  }
}

export const apiClient = new ApiClient(API_BASE_URL);