'use strict';

const createError = require("create-error");
const pgErrorCodes = require("pg-error-codes");

const DatabaseError = require("../database-error.js");
const getTable = require("../get-table");

let UndefinedColumnError = createError(DatabaseError, "UndefinedColumnError");

let messageRegex = /^(.+) - column "([^"]+)" (?:of relation "([^"]+)" )?does not exist$/;

module.exports = {
    error: UndefinedColumnError,
    errorName: "UndefinedColumnError",
    check: function checkType(error) {
        return (
            // PostgreSQL (via `pg`):
            (error.length != null && error.file != null && error.line != null && error.routine != null && error.code === "42703")
        )
    },
    convert: function convertError(error) {
        let messageMatch = messageRegex.exec(error.message);

        if (messageMatch == null) {
            throw new Error("Encountered unknown error format");
        }

        let [_, query, column, table] = messageMatch;

        let errorMessage;

        if (table != null) {
            errorMessage = `The '${column}' column does not exist in the '${table}' table`;
        } else {
            /* TODO: Maybe try to extract this from the query... somehow? */
            errorMessage = `The '${column}' column does not exist in (unknown table)`;
        }

        return new UndefinedColumnError(errorMessage, {
            originalError: error,
            pgCode: error.code,
            code: pgErrorCodes[error.code],
            query: query,
            table: table,
            column: column,
        });
    }
};