import * as plugins from './smartclickhouse.plugins.js';

export interface IClickhouseHttpClientOptions {
  username?: string;
  password?: string;
  url: string;
}

export class ClickhouseHttpClient {
  // STATIC
  public static async createAndStart(optionsArg: IClickhouseHttpClientOptions) {
    const clickhouseHttpInstance = new ClickhouseHttpClient(optionsArg);
    await clickhouseHttpInstance.start();
    return clickhouseHttpInstance;
  }

  // INSTANCE
  public options: IClickhouseHttpClientOptions;
  public webrequestInstance = new plugins.webrequest.WebrequestClient({
    logging: false,
  });
  public computedProperties: {
    connectionUrl: string;
    parsedUrl: plugins.smarturl.Smarturl;
  } = {
    connectionUrl: null,
    parsedUrl: null,
  };

  constructor(optionsArg: IClickhouseHttpClientOptions) {
    this.options = optionsArg;
  }

  public async start() {
    this.computedProperties.parsedUrl = plugins.smarturl.Smarturl.createFromUrl(this.options.url);
    console.log(this.computedProperties.parsedUrl);
    this.computedProperties.connectionUrl = this.computedProperties.parsedUrl.toString();
  }

  public async ping() {
    const ping = await this.webrequestInstance.request(
      this.computedProperties.connectionUrl.toString(),
      {
        method: 'GET',
        timeout: 1000,
      }
    );
    return ping.status === 200 ? true : false;
  }

  /**
   * Execute a query and return parsed JSONEachRow results
   */
  public async queryPromise(queryArg: string): Promise<any[]> {
    const returnArray: any[] = [];
    const response = await this.webrequestInstance.request(
      `${this.computedProperties.connectionUrl}?query=${encodeURIComponent(queryArg)}`,
      {
        method: 'POST',
        headers: this.getHeaders(),
      }
    );

    const responseText = await response.text();

    // Check for errors (ClickHouse returns non-200 for errors)
    if (!response.ok) {
      throw new Error(`ClickHouse query error: ${responseText.trim()}`);
    }

    if (response.headers.get('X-ClickHouse-Format') === 'JSONEachRow') {
      const jsonArray = responseText.split('\n');
      for (const jsonArg of jsonArray) {
        if (!jsonArg) continue;
        returnArray.push(JSON.parse(jsonArg));
      }
    } else if (responseText.trim()) {
      // Try to parse as JSONEachRow even without header (e.g. when FORMAT is in query)
      const lines = responseText.trim().split('\n');
      for (const line of lines) {
        if (!line) continue;
        try {
          returnArray.push(JSON.parse(line));
        } catch {
          // Not JSON — return raw text as single-element array
          return [{ raw: responseText.trim() }];
        }
      }
    }

    return returnArray;
  }

  /**
   * Execute a typed query returning T[]
   */
  public async queryTyped<T>(queryArg: string): Promise<T[]> {
    return this.queryPromise(queryArg) as Promise<T[]>;
  }

  /**
   * Insert documents as JSONEachRow
   */
  public async insertPromise(databaseArg: string, tableArg: string, documents: any[]) {
    const queryArg = `INSERT INTO ${databaseArg}.${tableArg} FORMAT JSONEachRow`;
    const response = await this.webrequestInstance.request(
      `${this.computedProperties.connectionUrl}?query=${encodeURIComponent(queryArg)}`,
      {
        method: 'POST',
        body: documents.map((docArg) => JSON.stringify(docArg)).join('\n'),
        headers: this.getHeaders(),
      }
    );

    if (!response.ok) {
      const errorText = await response.text();
      throw new Error(`ClickHouse insert error: ${errorText.trim()}`);
    }

    return response;
  }

  /**
   * Insert documents in batches of configurable size
   */
  public async insertBatch(
    databaseArg: string,
    tableArg: string,
    documents: any[],
    batchSize: number = 10000,
  ) {
    for (let i = 0; i < documents.length; i += batchSize) {
      const batch = documents.slice(i, i + batchSize);
      await this.insertPromise(databaseArg, tableArg, batch);
    }
  }

  /**
   * Execute a mutation (ALTER TABLE UPDATE/DELETE) and optionally wait for completion
   */
  public async mutatePromise(queryArg: string): Promise<void> {
    const response = await this.webrequestInstance.request(
      `${this.computedProperties.connectionUrl}?query=${encodeURIComponent(queryArg)}`,
      {
        method: 'POST',
        headers: this.getHeaders(),
      }
    );

    if (!response.ok) {
      const errorText = await response.text();
      throw new Error(`ClickHouse mutation error: ${errorText.trim()}`);
    }
  }

  private getHeaders() {
    const headers: { [key: string]: string } = {};
    if (this.options.username) {
      headers['X-ClickHouse-User'] = this.options.username;
    }
    if (this.options.password) {
      headers['X-ClickHouse-Key'] = this.options.password;
    }
    return headers;
  }
}