'use strict';

angular.module('myApp.i18n', ['izhukov.utils'])
  .factory('_', ['$rootScope', '$locale', function($rootScope, $locale) {
    var locale = Config.I18n.locale;
    var messages = Config.I18n.messages;
    var fallbackMessages = Config.I18n.fallback_messages;
    var paramRegEx = /\{\s*([a-zA-Z\d\-_]+)(?:\s*:\s*(.*?))?\s*\}/g;

    function insertParams(msgstr, params) {
      return msgstr.replace(paramRegEx, function ($0, paramKey, nestedMsgStr) {
        var param = params[paramKey];
        if (param === undefined) {
          console.warn('[i18n] missing param ' + paramKey + ' for message "' + msgstr + '"');
          return '';
        }
        if (nestedMsgStr !== undefined) {
          param = insertParams(param, nestedMsgStr.split('|'));
        }
        return param.toString().trim();
      });
    }

    function encodeEntities(value) {
      return value.
        replace(/&/g, '&').
        replace(/([^\#-~| |!\n\*])/g, function (value) { // non-alphanumeric
          return '&#' + value.charCodeAt(0) + ';';
        }).
        replace(/</g, '&lt;').
        replace(/>/g, '&gt;');
    }

    function parseMarkdownString(msgstr, msgid) {
      msgstr = msgstr.replace(/\*\*(.+?)\*\*/g, "<strong>$1</strong>")
        .replace(/\n/g, "<br/>");
      return msgstr;
    }

    function _(msgid, params) {
      var raw = false;
      var msgstr = msgid;

      if (msgid.substr(-4) === '_raw') {
        raw = true;
        msgid = msgid.substr(0, msgid.length - 4);
      }

      if (messages.hasOwnProperty(msgid)) {
        msgstr = messages[msgid];
      } else if (fallbackMessages.hasOwnProperty(msgid)) {
        msgstr = fallbackMessages[msgid];
        console.warn('[i18n] missing locale key ' + locale + ' / ' + msgid);
      } else {
        console.warn('[i18n] missing key ' + msgid);
        return msgid;
      }

      if (!raw) {
        msgstr = encodeEntities(msgstr);
      }
      if (msgid.substr(-3) == '_md') {
        msgstr = parseMarkdownString(msgstr);
      }

      if (arguments.length > 1) {
        if (typeof params == 'string') {
          Array.prototype.shift.apply(arguments);
          msgstr = insertParams(msgstr, arguments);
        } else {
          msgstr = insertParams(msgstr, params);
        }
      }

      return msgstr;
    }

    _.locale = function () {
      return locale;
    };

    _.pluralize = function (msgid) {
      var categories = $rootScope.$eval(_(msgid + '_raw'));
      return function (count) {
        return (categories[$locale.pluralCat(count)] || '').replace('{}', count);
      }
    };

    return _;
  }])

  .filter('i18n', ['_', function(_) {
    return function (msgid, params) {
      return _(msgid + '_raw', params);
    }
  }])

  .directive('ngPluralize', ['_', function(_) {
    return {
      restrict: 'EA',
      priority: 1, // execute before built-in ngPluralize
      compile: function(element) {
        var msgid = element.attr('when');
        var msgstr = _(msgid + '_raw');
        element.attr('when', msgstr);
      }
    }
  }])

  .directive('myI18n', ['_', function(_) {
    return {
      restrict: 'EA',
      compile: function(element) {
        var params = element.children('my-i18n-param:not([name]), [my-i18n-param=""]:not([name])').map(function(index, param) {
          return param.outerHTML;
        }).toArray();
        element.children('my-i18n-param[name], [my-i18n-param]:not([my-i18n-param=""]), [my-i18n-param][name]').each(function(i, param) {
          params[angular.element(param).attr('my-i18n-param') || angular.element(param).attr('name')] = param.outerHTML;
        });
        element.children('my-i18n-param').remove();
        var formats = element.attr("my-i18n") || element.attr("msgid") ? element : element.children('my-i18n-format, [my-i18n-format]');
        formats.each(function(index, element) {
          var format = angular.element(element);
          var msgid = format.attr("my-i18n") || format.attr("msgid") || format.attr("my-i18n-format") || format.html().replace(/\s+/g, ' ').trim();
          var msgstr = _(msgid, params);
          format.html(msgstr);
        });
      }
    }
  }]);