/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

/* brooklyn utility methods */

define([
    'jquery', 'underscore'
], function ($, _) {

    var Util = {};

    /**
     * @return {string} empty string if s is null or undefined, otherwise result of _.escape(s)
     */
    Util.escape = function (s) {
        if (s == undefined || s == null) return "";
        return _.escape(s);
    };

    function isWholeNumber(v) {
        return (Math.abs(Math.round(v) - v) < 0.000000000001);
    }

    Util.roundIfNumberToNumDecimalPlaces = function (v, mantissa) {
        if (!_.isNumber(v) || mantissa < 0)
            return v;

        if (isWholeNumber(v))
            return Math.round(v);

        var vk = v, xp = 1;
        for (var i=0; i < mantissa; i++) {
            vk *= 10;
            xp *= 10;
            if (isWholeNumber(vk)) {
                return Math.round(vk)/xp;
            }
        }
        return Number(v.toFixed(mantissa));
    };

    Util.toDisplayString = function(data) {
        if (data==null) return null;
        data = Util.roundIfNumberToNumDecimalPlaces(data, 4);
        if (typeof data !== 'string')
            data = JSON.stringify(data);
        return Util.escape(data);
    };

    Util.toTextAreaString = function(data) {
        if (data==null) return null;
        data = Util.roundIfNumberToNumDecimalPlaces(data, 8);
        if (typeof data !== 'string')
            data = JSON.stringify(data, null, 2);
        return data;
    };

    if (!String.prototype.trim) {
        // some older javascripts do not support 'trim' (including jasmine spec runner) so let's define it
        String.prototype.trim = function(){
            return this.replace(/^\s+|\s+$/g, '');
        };
    }

    // from http://stackoverflow.com/questions/646628/how-to-check-if-a-string-startswith-another-string
    if (typeof String.prototype.startsWith != 'function') {
        String.prototype.startsWith = function (str){
            return this.slice(0, str.length) == str;
        };
    }
    if (typeof String.prototype.endsWith != 'function') {
        String.prototype.endsWith = function (str){
            return this.slice(-str.length) == str;
        };
    }
    
    // poor-man's copy
    Util.promptCopyToClipboard = function(text) {
        window.prompt("To copy to the clipboard, press Ctrl+C then Enter.", text);
    };

    /**
     * Returns the path component of a string URL. e.g. http://example.com/bob/bob --> /bob/bob
     */
    Util.pathOf = function(string) {
        if (!string) return "";
        var a = document.createElement("a");
        a.href = string;
        return a.pathname;
    };

    /**
     * Extracts the value of the given input. Returns true/false for for checkboxes
     * rather than "on" or "off".
     */
    Util.inputValue = function($input) {
        if ($input.attr("type") === "checkbox") {
            return $input.is(":checked");
        } else {
            return $input.val();
        }
    };

    /**
     * Updates or initialises the given model with the values of named elements under
     * the given element. Force-updates the model by setting silent: true.
     */
    Util.bindModelFromForm = function(modelOrConstructor, $el) {
        var model = _.isFunction(modelOrConstructor) ? new modelOrConstructor() : modelOrConstructor;
        var inputs = {};

        // Look up all named elements
        $("[name]", $el).each(function(idx, inp) {
            var input = $(inp);
            var name = input.attr("name");
            inputs[name] = Util.inputValue(input);
        });
        model.set(inputs, { silent: true });
        return model;
    };

    /**
     * Parses xhrResponse.responseText as JSON and returns its message. Returns
     * alternate message if parsing fails or the parsed object has no message.
     * @param {jqXHR} xhrResponse
     * @param {string} alternateMessage
     * @param {string=} logMessage if false or null, does not log;
     *      otherwise it logs a message and the xhrResponse, with logMessage
     *      (or with alternateMessage if logMessage is true)
     * @returns {*}
     */
    Util.extractError = function (xhrResponse, alternateMessage, logMessage) {
        if (logMessage) {
            if (logMessage === true) {
                console.error(alternateMessage);
            } else {
                console.error(logMessage);
            }
            console.log(xhrResponse);
        }
        
        try {
            var response = JSON.parse(xhrResponse.responseText);
            return response.message ? response.message : alternateMessage;
        } catch (e) {
            return alternateMessage;
        }
    };
    
    secretWords = [ "password", "passwd", "credential", "secret", "private", "access.cert", "access.key" ];
    
    Util.isSecret = function (key) {
        if (!key) return false;
        key = key.toString().toLowerCase();
        for (secretWord in secretWords)
            if (key.indexOf(secretWords[secretWord]) >= 0)
                return true;
        return false; 
    };

    Util.logout = function logout() {
        window.location.href = 'logout.html';
    };

    Util.setSelectionRange = function (input, selectionStart, selectionEnd) {
      if (input.setSelectionRange) {
        input.focus();
        input.setSelectionRange(selectionStart, selectionEnd);
      }
      else if (input.createTextRange) {
        var range = input.createTextRange();
        range.collapse(true);
        range.moveEnd('character', selectionEnd);
        range.moveStart('character', selectionStart);
        range.select();
      }
    };
            
    Util.setCaretToPos = function (input, pos) {
      Util.setSelectionRange(input, pos, pos);
    };

    $.fn.setCaretToStart = function() {
      this.each(function(index, elem) {
        Util.setCaretToPos(elem, 0);
        $(elem).scrollTop(0);
      });
      return this;
    };

    $("#logout-link").on("click", function (e) {
        e.preventDefault();
        Util.logout();
        return false;
    });

    return Util;

});