import {
  UnexpectedStateError,
  InvalidInputError,
} from '../errors';
import {
  createSqlTokenSqlFragment,
} from '../factories';
import {
  type ArraySqlToken,
  type SqlFragment,
} from '../types';
import {
  escapeIdentifier,
  isPrimitiveValueExpression,
  isSqlToken,
} from '../utilities';

export const createArraySqlFragment = (token: ArraySqlToken, greatestParameterPosition: number): SqlFragment => {
  let placeholderIndex = greatestParameterPosition;

  for (const value of token.values) {
    if (token.memberType === 'bytea') {
      if (Buffer.isBuffer(value)) {
        continue;
      } else {
        throw new InvalidInputError('Invalid array member type. Non-buffer value bound to bytea type.');
      }
    }

    if (!isPrimitiveValueExpression(value)) {
      throw new InvalidInputError('Invalid array member type. Must be a primitive value expression.');
    }
  }

  const values = [
    token.values,
  ];

  placeholderIndex++;

  let sql = '$' + String(placeholderIndex) + '::';

  if (isSqlToken(token.memberType) && token.memberType.type === 'SLONIK_TOKEN_SQL') {
    const sqlFragment = createSqlTokenSqlFragment(
      token.memberType,
      placeholderIndex,
    );

    if (sqlFragment.values.length > 0) {
      throw new UnexpectedStateError('Type is not expected to have a value binding.');
    }

    sql += sqlFragment.sql;
  } else if (typeof token.memberType === 'string') {
    sql += escapeIdentifier(token.memberType) + '[]';
  } else {
    throw new InvalidInputError('Unsupported `memberType`. `memberType` must be a string or SqlToken of "SLONIK_TOKEN_SQL" type.');
  }

  return {
    sql,
    values,
  };
};