// 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.


// This file creates a set of helper functions that will be loaded for all html
// templates. These functions should be self contained and not rely on any
// external dependencies as they are loaded prior to the application. We may
// want to change this later, but for now this should be thought of as a
// "purely functional" helper system.


define([
  "jquery",
  "lodash"
],

function ($, _) {

  var onWindowResize = {};

  var utils = {

    // Thanks to: http://stackoverflow.com/a/2880929
    getParams: function (queryString) {
      if (queryString) {
        // I think this could be combined into one if
        if (queryString.substring(0, 1) === "?") {
          queryString = queryString.substring(1);
        } else if (queryString.indexOf('?') > -1) {
          queryString = queryString.split('?')[1];
        }
      }
      var hash = window.location.hash.split('?')[1];
      queryString = queryString || hash || window.location.search.substring(1);
      var match,
      urlParams = {},
      pl     = /\+/g,  // Regex for replacing addition symbol with a space
      search = /([^&=]+)=?([^&]*)/g,
      decode = function (s) { return decodeURIComponent(s.replace(pl, " ")); },
      query  = queryString;

      if (queryString) {
        while ((match = search.exec(query))) {
          urlParams[decode(match[1])] = decode(match[2]);
        }
      }

      return urlParams;
    },

    // this takes the current URL and replaces all ?x=x with whatever new params are passed
    replaceQueryParams: function (params) {
      var fragment = window.location.hash.replace(/\?.*$/, "");
      if (!_.isEmpty(params)) {
        fragment = fragment + "?" + $.param(params);
      }
      return fragment;
    },

    addWindowResize: function (fun, key) {
      onWindowResize[key] = fun;
      // You shouldn't need to call it here. Just define it at startup and each time it will loop
      // through all the functions in the hash.
      //app.initWindowResize();
    },

    removeWindowResize: function (key) {
      delete onWindowResize[key];
      utils.initWindowResize();
    },

    initWindowResize: function () {
      //when calling this it should be overriding what was called previously
      window.onresize = function (e) {
        // could do this instead of the above for loop
        _.each(onWindowResize, function (fn) {
          fn();
        });
      };
    },

    removeSpecialCharacters: function (name) {
      return name.replace(/[^\w\s]/gi, "");
    },

    safeURLName: function (name) {
      var testName = name || "";
      var checkforBad = testName.match(/[\$\-/,+-]/g);
      return (checkforBad !== null) ? encodeURIComponent(name) : name;
    },

    getDocTypeFromId: function (id) {
      if (id && /^_design\//.test(id)) {
        return 'design doc';
      }

      return 'doc';
    },

    // Need this to work around backbone router thinking _design/foo
    // is a separate route. Alternatively, maybe these should be
    // treated separately. For instance, we could default into the
    // json editor for docs, or into a ddoc specific page.
    getSafeIdForDoc: function (id) {
      if (utils.getDocTypeFromId(id) === 'design doc') {
        var ddoc = id.replace(/^_design\//, '');
        return '_design/' + utils.safeURLName(ddoc);
      }

      return utils.safeURLName(id);
    },

    // a pair of simple local storage wrapper functions. These ward against problems getting or
    // setting (e.g. local storage full) and allow you to get/set complex data structures
    localStorageSet: function (key, value) {
      if (_.isObject(value) || _.isArray(value)) {
        value = JSON.stringify(value);
      }
      var success = true;
      try {
        window.localStorage.setItem(key, value);
      } catch (e) {
        success = false;
      }
      return success;
    },

    localStorageGet: function (key) {
      var data;
      if (_.has(window.localStorage, key)) {
        data = window.localStorage[key];
        try {
          return JSON.parse(data);
        } catch (e) {
          return data;
        }
      }
      return data;
    },

    stripHTML: function (str) {
      var tmpElement = document.createElement("div");
      tmpElement.innerHTML = str;
      return tmpElement.textContent || tmpElement.innerText;
    }
  };

  return utils;
});