/**
 * @fileoverview Defines a storage for rules.
 * @author Nicholas C. Zakas
 */

"use strict";

//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------

var loadRules = require("./load-rules");

//------------------------------------------------------------------------------
// Privates
//------------------------------------------------------------------------------

var rules = Object.create(null);

//------------------------------------------------------------------------------
// Public Interface
//------------------------------------------------------------------------------

/**
 * Registers a rule module for rule id in storage.
 * @param {String} ruleId Rule id (file name).
 * @param {Function} ruleModule Rule handler.
 * @returns {void}
 */
function define(ruleId, ruleModule) {
    rules[ruleId] = ruleModule;
}

exports.define = define;

/**
 * Loads and registers all rules from passed rules directory.
 * @param {String} [rulesDir] Path to rules directory, may be relative. Defaults to `lib/rules`.
 * @returns {void}
 */
function load(rulesDir) {
    var newRules = loadRules(rulesDir);
    Object.keys(newRules).forEach(function(ruleId) {
        define(ruleId, newRules[ruleId]);
    });
}

exports.load = load;

/**
 * Registers all given rules of a plugin.
 * @param {Object} pluginRules A key/value map of rule definitions.
 * @param {String} pluginName The name of the plugin without prefix (`eslint-plugin-`).
 * @returns {void}
 */
exports.import = function (pluginRules, pluginName) {
    Object.keys(pluginRules).forEach(function (ruleId) {
        var qualifiedRuleId = pluginName + "/" + ruleId,
            rule = pluginRules[ruleId];

        define(qualifiedRuleId, rule);
    });
};

/**
 * Access rule handler by id (file name).
 * @param {String} ruleId Rule id (file name).
 * @returns {Function} Rule handler.
 */
exports.get = function(ruleId) {
    return rules[ruleId];
};

/**
 * Reset rules storage.
 * Should be used only in tests.
 * @returns {void}
 */
exports.testClear = function() {
    rules = Object.create(null);
};

//------------------------------------------------------------------------------
// Initialization
//------------------------------------------------------------------------------

// loads built-in rules
load();