import {
  BaseSmartTags,
  PgColumn,
  PgFkColumn,
  PgTable,
  PgType,
} from '../../abstractions';
import { buildName } from '../pg-sql-gen-utils';

export class FkColumn implements PgFkColumn {
  name: string;
  readonly table: PgTable;
  readonly type: PgType;
  readonly referencedPk: PgColumn;
  readonly targetPk: PgColumn;
  readonly fkName: string;

  /**
   * Constructor for FkColumn.
   * @param targetPk - PK to the 'target' table.
   * @param table - Reference to the parent table.
   */
  constructor(targetPk: PgColumn, table: PgTable) {
    this.targetPk = targetPk;
    this.name = buildName(targetPk.table.name, targetPk.name);
    this.table = table;
    this.fkName = buildName(table.name, this.name, 'fkey');
    this.type = targetPk.type;
    this.referencedPk = targetPk;
  }
  buildSmartTags(): BaseSmartTags {
    return {};
  }

  buildExpression(): string {
    return `${this.name} ${this.type} REFERENCES ${this.referencedPk.table.name} ON DELETE CASCADE`;
  }
  buildAdditionalStatements(): string[] {
    return [`CREATE INDEX ON ${this.table.buildFullName()} (${this.name})`];
  }
}