import * as queries from '../db/queries.constant';

export class QueryBuilder {
  readonly sql: string;
  readonly queryParams: unknown[];

  /**
   * Create a QueryBuilder from a query constant path.
   *
   * @param queryPath Path to query in queries.constant.ts (e.g., 'MARKET_CALLS_QUERIES.SELECT_ALL')
   * @param params Parameters to bind (? placeholders in SQL)
   */
  constructor(queryPath: string, params: unknown[] = []) {
    this.sql = this.lookupQuery(queryPath);
    this.queryParams = params;

    // Validate parameter count matches placeholders
    const placeholderCount = (this.sql.match(/\?/g) || []).length;
    if (this.queryParams.length !== placeholderCount) {
      throw new Error(
        `Parameter mismatch for query "${queryPath}": expected ${placeholderCount}, got ${this.queryParams.length}`,
      );
    }
  }

  /**
   * Look up a query from queries.constant.ts.
   * Supports nested paths like "MARKET_CALLS_QUERIES.SELECT_ALL".
   *
   * @param queryPath Path to query (e.g., 'MARKET_CALLS_QUERIES.SELECT_ALL')
   * @returns The SQL query string
   * @throws Error if query not found
   */
  private lookupQuery(queryPath: string): string {
    const parts = queryPath.split('.');

    // Navigate through the nested objects
    let current: any = queries;
    for (const part of parts) {
      if (!(part in current)) {
        throw new Error(
          `Query not found: "${queryPath}". Make sure it exists in queries.constant.ts`,
        );
      }
      current = current[part];
    }

    if (typeof current !== 'string') {
      throw new Error(`Invalid query: "${queryPath}" must be a string, got ${typeof current}`);
    }

    // Clean up the SQL (remove extra whitespace)
    return current.trim();
  }
}