'use strict';

const createError = require("create-error");
const pgErrorCodes = require("pg-error-codes");
const DatabaseError = require("../database-error.js");
const splitValues = require("../split-values");

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

let detailsRegex = /Key \(([^\)]+)\)=\(([^\)]+)\) already exists\./;

module.exports = {
    error: UniqueConstraintViolationError,
    errorName: "UniqueConstraintViolationError",
    check: function checkType(error) {
        return (
            // PostgreSQL (via `pg`):
            (error.length != null && error.file != null && error.line != null && error.routine != null && error.code === "23505")
        )
    },
    convert: function convertError(error) {
        let [_, columnValue, valueValue] = detailsRegex.exec(error.detail);

        let column, columns, value, values, messageColumn, messageValue, isComposite;

        if (columnValue.includes(",")) {
            columns = splitValues(columnValue);
            messageColumn = `columns ${columns.map(column => `'${column}'`).join(", ")}`;
            isComposite = true;
        } else {
            column = columnValue;
            messageColumn = `column '${column}'`;
            isComposite = false;
        }

        if (valueValue.includes(",")) {
            values = splitValues(valueValue);
            messageValue = `Values ${values.map(value => `'${value}'`).join(", ")} already exist`;
        } else {
            value = valueValue;
            messageValue = `Value '${value}' already exists`;
        }

        return new UniqueConstraintViolationError(`${messageValue} for ${messageColumn} in table '${error.table}'`, {
            originalError: error,
            pgCode: error.code,
            code: pgErrorCodes[error.code],
            schema: error.schema,
            table: error.table,
            column: column,
            columns: columns,
            value: value,
            values: values,
            isComposite: isComposite,
            constraint: error.constraint
        });
    }
};