import axios, { AxiosResponse, AxiosRequestHeaders } from 'axios';

/**
 * Configuration interface for FirecrawlApp.
 */
export interface FirecrawlAppConfig {
  apiKey?: string | null;
}

/**
 * Generic parameter interface.
 */
export interface Params {
  [key: string]: any;
}

/**
 * Response interface for scraping operations.
 */
export interface ScrapeResponse {
  success: boolean;
  data?: any;
  error?: string;
}

/**
 * Response interface for searching operations.
 */
export interface SearchResponse {
  success: boolean;
  data?: any;
  error?: string;
}
/**
 * Response interface for crawling operations.
 */
export interface CrawlResponse {
  success: boolean;
  jobId?: string;
  data?: any;
  error?: string;
}

/**
 * Response interface for job status checks.
 */
export interface JobStatusResponse {
  success: boolean;
  status: string;
  jobId?: string;
  data?: any;
  error?: string;
}

/**
 * Main class for interacting with the Firecrawl API.
 */
export default class FirecrawlApp {
  private apiKey: string;

  /**
   * Initializes a new instance of the FirecrawlApp class.
   * @param {FirecrawlAppConfig} config - Configuration options for the FirecrawlApp instance.
   */
  constructor({ apiKey = null }: FirecrawlAppConfig) {
    this.apiKey = apiKey || '';
    if (!this.apiKey) {
      throw new Error('No API key provided');
    }
  }

  /**
   * Scrapes a URL using the Firecrawl API.
   * @param {string} url - The URL to scrape.
   * @param {Params | null} params - Additional parameters for the scrape request.
   * @returns {Promise<ScrapeResponse>} The response from the scrape operation.
   */
  async scrapeUrl(url: string, params: Params | null = null): Promise<ScrapeResponse> {
    const headers: AxiosRequestHeaders = {
      'Content-Type': 'application/json',
      'Authorization': `Bearer ${this.apiKey}`,
    } as AxiosRequestHeaders;
    let jsonData: Params = { url };
    if (params) {
      jsonData = { ...jsonData, ...params };
    }
    try {
      const response: AxiosResponse = await axios.post('https://api.firecrawl.dev/v0/scrape', jsonData, { headers });
      if (response.status === 200) {
        const responseData = response.data;
        if (responseData.success) {
          return responseData; 
        } else {
          throw new Error(`Failed to scrape URL. Error: ${responseData.error}`);
        }
      } else {
        this.handleError(response, 'scrape URL');
      }
    } catch (error: any) {
      throw new Error(error.message);
    }
    return { success: false, error: 'Internal server error.' };
  }

  /**
   * Searches for a query using the Firecrawl API.
   * @param {string} query - The query to search for.
   * @param {Params | null} params - Additional parameters for the search request.
   * @returns {Promise<SearchResponse>} The response from the search operation.
   */
  async search(query: string, params: Params | null = null): Promise<SearchResponse> {
    const headers: AxiosRequestHeaders = {
      'Content-Type': 'application/json',
      'Authorization': `Bearer ${this.apiKey}`,
    } as AxiosRequestHeaders;
    let jsonData: Params = { query };
    if (params) {
      jsonData = { ...jsonData, ...params };
    }
    try {
      const response: AxiosResponse = await axios.post('https://api.firecrawl.dev/v0/search', jsonData, { headers });
      if (response.status === 200) {
        const responseData = response.data;
        if (responseData.success) {
          return responseData; 
        } else {
          throw new Error(`Failed to search. Error: ${responseData.error}`);
        }
      } else {
        this.handleError(response, 'search');
      }
    } catch (error: any) {
      throw new Error(error.message);
    }
    return { success: false, error: 'Internal server error.' };
  }

  /**
   * Initiates a crawl job for a URL using the Firecrawl API.
   * @param {string} url - The URL to crawl.
   * @param {Params | null} params - Additional parameters for the crawl request.
   * @param {boolean} waitUntilDone - Whether to wait for the crawl job to complete.
   * @param {number} timeout - Timeout in seconds for job status checks.
   * @param {string} idempotencyKey - Optional idempotency key for the request.
   * @returns {Promise<CrawlResponse | any>} The response from the crawl operation.
   */
  async crawlUrl(url: string, params: Params | null = null, waitUntilDone: boolean = true, timeout: number = 2, idempotencyKey?: string): Promise<CrawlResponse | any> {
    const headers = this.prepareHeaders(idempotencyKey);
    let jsonData: Params = { url };
    if (params) {
      jsonData = { ...jsonData, ...params };
    }
    try {
      const response: AxiosResponse = await this.postRequest('https://api.firecrawl.dev/v0/crawl', jsonData, headers);
      if (response.status === 200) {
        const jobId: string = response.data.jobId;
        if (waitUntilDone) {
          return this.monitorJobStatus(jobId, headers, timeout);
        } else {
          return { success: true, jobId };
        }
      } else {
        this.handleError(response, 'start crawl job');
      }
    } catch (error: any) {
      console.log(error)
      throw new Error(error.message);
    }
    return { success: false, error: 'Internal server error.' };
  }

  /**
   * Checks the status of a crawl job using the Firecrawl API.
   * @param {string} jobId - The job ID of the crawl operation.
   * @returns {Promise<JobStatusResponse>} The response containing the job status.
   */
  async checkCrawlStatus(jobId: string): Promise<JobStatusResponse> {
    const headers: AxiosRequestHeaders = this.prepareHeaders();
    try {
      const response: AxiosResponse = await this.getRequest(`https://api.firecrawl.dev/v0/crawl/status/${jobId}`, headers);
      if (response.status === 200) {
        return response.data;
      } else {
        this.handleError(response, 'check crawl status');
      }
    } catch (error: any) {
      throw new Error(error.message);
    }
    return { success: false, status: 'unknown', error: 'Internal server error.' };
  }

  /**
   * Prepares the headers for an API request.
   * @returns {AxiosRequestHeaders} The prepared headers.
   */
  prepareHeaders(idempotencyKey?: string): AxiosRequestHeaders {
    return {
      'Content-Type': 'application/json',
      'Authorization': `Bearer ${this.apiKey}`,
      ...(idempotencyKey ? { 'x-idempotency-key': idempotencyKey } : {}),
    } as AxiosRequestHeaders & { 'x-idempotency-key'?: string };
  }

  /**
   * Sends a POST request to the specified URL.
   * @param {string} url - The URL to send the request to.
   * @param {Params} data - The data to send in the request.
   * @param {AxiosRequestHeaders} headers - The headers for the request.
   * @returns {Promise<AxiosResponse>} The response from the POST request.
   */
  postRequest(url: string, data: Params, headers: AxiosRequestHeaders): Promise<AxiosResponse> {
    return axios.post(url, data, { headers });
  }

  /**
   * Sends a GET request to the specified URL.
   * @param {string} url - The URL to send the request to.
   * @param {AxiosRequestHeaders} headers - The headers for the request.
   * @returns {Promise<AxiosResponse>} The response from the GET request.
   */
  getRequest(url: string, headers: AxiosRequestHeaders): Promise<AxiosResponse> {
    return axios.get(url, { headers });
  }

  /**
   * Monitors the status of a crawl job until completion or failure.
   * @param {string} jobId - The job ID of the crawl operation.
   * @param {AxiosRequestHeaders} headers - The headers for the request.
   * @param {number} timeout - Timeout in seconds for job status checks.
   * @returns {Promise<any>} The final job status or data.
   */
  async monitorJobStatus(jobId: string, headers: AxiosRequestHeaders, timeout: number): Promise<any> {
    while (true) {
      const statusResponse: AxiosResponse = await this.getRequest(`https://api.firecrawl.dev/v0/crawl/status/${jobId}`, headers);
      if (statusResponse.status === 200) {
        const statusData = statusResponse.data;
        if (statusData.status === 'completed') {
          if ('data' in statusData) {
            return statusData.data;
          } else {
            throw new Error('Crawl job completed but no data was returned');
          }
        } else if (['active', 'paused', 'pending', 'queued'].includes(statusData.status)) {
          if (timeout < 2) {
            timeout = 2;
          }
          await new Promise(resolve => setTimeout(resolve, timeout * 1000)); // Wait for the specified timeout before checking again
        } else {
          throw new Error(`Crawl job failed or was stopped. Status: ${statusData.status}`);
        }
      } else {
        this.handleError(statusResponse, 'check crawl status');
      }
    }
  }

  /**
   * Handles errors from API responses.
   * @param {AxiosResponse} response - The response from the API.
   * @param {string} action - The action being performed when the error occurred.
   */
  handleError(response: AxiosResponse, action: string): void {
    if ([402, 409, 500].includes(response.status)) {
      const errorMessage: string = response.data.error || 'Unknown error occurred';
      throw new Error(`Failed to ${action}. Status code: ${response.status}. Error: ${errorMessage}`);
    } else {
      throw new Error(`Unexpected error occurred while trying to ${action}. Status code: ${response.status}`);
    }
  }
}