/**
 * Copyright 2014 IBM, Antoine Aflalo
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/


RED.settings = (function () {

    var loadedSettings = {};

    var hasLocalStorage = function () {
        try {
            return 'localStorage' in window && window['localStorage'] !== null;
        } catch (e) {
            return false;
        }
    };

    var set = function (key, value) {
        if (!hasLocalStorage()) {
            return;
        }
        localStorage.setItem(key, JSON.stringify(value));
    };

    /**
     * If the key is not set in the localStorage it returns <i>undefined</i>
     * Else return the JSON parsed value
     * @param key
     * @returns {*}
     */
    var get = function (key) {
        if (!hasLocalStorage()) {
            return undefined;
        }
        return JSON.parse(localStorage.getItem(key));
    };

    var remove = function (key) {
        if (!hasLocalStorage()) {
            return;
        }
        localStorage.removeItem(key);
    };

    var setProperties = function(data) {
        for (var prop in loadedSettings) {
            if (loadedSettings.hasOwnProperty(prop) && RED.settings.hasOwnProperty(prop)) {
                delete RED.settings[prop];
            }
        }
        for (prop in data) {
            if (data.hasOwnProperty(prop)) {
                RED.settings[prop] = data[prop];
            }
        }
        loadedSettings = data;
    };

    var init = function (done) {
        var accessTokenMatch = /[?&]access_token=(.*?)(?:$|&)/.exec(window.location.search);
        if (accessTokenMatch) {
            var accessToken = accessTokenMatch[1];
            RED.settings.set("auth-tokens",{access_token: accessToken});
            window.location.search = "";
        }

        $.ajaxSetup({
            beforeSend: function(jqXHR,settings) {
                // Only attach auth header for requests to relative paths
                if (!/^\s*(https?:|\/|\.)/.test(settings.url)) {
                    var auth_tokens = RED.settings.get("auth-tokens");
                    if (auth_tokens) {
                        jqXHR.setRequestHeader("Authorization","Bearer "+auth_tokens.access_token);
                    }
                }
            }
        });

        load(done);
    }

    var load = function(done) {
        $.ajax({
            headers: {
                "Accept": "application/json"
            },
            dataType: "json",
            cache: false,
            url: 'settings',
            success: function (data) {
                setProperties(data);
                if (RED.settings.user && RED.settings.user.anonymous) {
                    RED.settings.remove("auth-tokens");
                }
                console.log("Node-RED: " + data.version);
                done();
            },
            error: function(jqXHR,textStatus,errorThrown) {
                if (jqXHR.status === 401) {
                    if (/[?&]access_token=(.*?)(?:$|&)/.test(window.location.search)) {
                        window.location.search = "";
                    }
                    RED.user.login(function() { load(done); });
                } else {
                    console.log("Unexpected error:",jqXHR.status,textStatus);
                }
            }
        });
    };

    function theme(property,defaultValue) {
        if (!RED.settings.editorTheme) {
            return defaultValue;
        }
        var parts = property.split(".");
        var v = RED.settings.editorTheme;
        try {
            for (var i=0;i<parts.length;i++) {
                v = v[parts[i]];
            }
            if (v === undefined) {
                return defaultValue;
            }
            return v;
        } catch(err) {
            return defaultValue;
        }
    }

    return {
        init: init,
        load: load,
        set: set,
        get: get,
        remove: remove,
        theme: theme
    }
})
();