'use strict';

const { create } = require("error-chain");
const pgErrorCodes = require("pg-error-codes");

const DatabaseError = require("../database-error.js");
const getColumns = require("../get-columns");
const getValues = require("../get-values");

let CheckConstraintViolationError = create("CheckConstraintViolationError", { inheritsFrom: DatabaseError });

let messageRegex = /^(.+) - new row for relation "([^"]+)" violates check constraint "([^"]+)"$/;

module.exports = {
	error: CheckConstraintViolationError,
	errorName: "CheckConstraintViolationError",
	check: function checkType(error) {
		return (
		// PostgreSQL (via `pg`):
			(error.length != null && error.file != null && error.line != null && error.routine != null && error.code === "23514")
		);
	},
	convert: function convertError(error) {
		let messageMatch = messageRegex.exec(error.message);

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

		let [_, query, _table, _constraint] = messageMatch;

		let columns = getColumns(query);

		let offendingColumn, message;

		if (columns != null) {
			/* This is the naming convention that Knex uses for .enum() in PostgreSQL */
			offendingColumn = columns.find(column => {
				return error.constraint === `${error.table}_${column}_check`;
			});

			message = `Value violates the '${error.constraint}' constraint for the '${offendingColumn}' column in the '${error.table}' table`;
		} else {
			message = `Value violates the '${error.constraint}' constraint for the '${error.table}' table`;
		}

		return new CheckConstraintViolationError(message, {
			originalError: error,
			pgCode: error.code,
			code: pgErrorCodes[error.code],
			query: query,
			schema: error.schema,
			table: error.table,
			column: offendingColumn,
			constraint: error.constraint,
			values: getValues(error.detail)
		});
	}
};