/*
 * # Semantic - API
 * http://github.com/semantic-org/semantic-ui/
 *
 *
 * Copyright 2013 Contributors
 * Released under the MIT license
 * http://opensource.org/licenses/MIT
 *
 */

;(function ( $, window, document, undefined ) {

$.api = $.fn.api = function(parameters) {

  var
    // use window context if none specified
    $allModules     = $.isFunction(this)
        ? $(window)
        : $(this),
    moduleSelector  = $allModules.selector || '',
    time            = new Date().getTime(),
    performance     = [],

    query           = arguments[0],
    methodInvoked   = (typeof query == 'string'),
    queryArguments  = [].slice.call(arguments, 1),
    returnedValue
  ;

  $allModules
    .each(function() {
      var
        settings        = $.extend(true, {}, $.fn.api.settings, parameters),

        // internal aliases
        namespace       = settings.namespace,
        metadata        = settings.metadata,
        selector        = settings.selector,
        error           = settings.error,
        className       = settings.className,

        // define namespaces for modules
        eventNamespace  = '.' + namespace,
        moduleNamespace = 'module-' + namespace,

        // element that creates request
        $module         = $(this),
        $form           = $module.closest(selector.form),

        // context used for state
        $context        = (settings.stateContext)
          ? $(settings.stateContext)
          : $module,

        // request details
        ajaxSettings,
        requestSettings,
        url,
        data,

        // standard module
        element         = this,
        instance        = $module.data(moduleNamespace),
        module
      ;

      module = {

        initialize: function() {
          var
            triggerEvent = module.get.event()
          ;
          if(!methodInvoked) {
            if( triggerEvent ) {
              module.debug('Attaching API events to element', triggerEvent);
              $module
                .on(triggerEvent + eventNamespace, module.query)
              ;
            }
            else {
              module.query();
            }
          }
          module.instantiate();
        },

        instantiate: function() {
          module.verbose('Storing instance of module', module);
          instance = module;
          $module
            .data(moduleNamespace, instance)
          ;
        },

        destroy: function() {
          module.verbose('Destroying previous module for', element);
          $module
            .removeData(moduleNamespace)
            .off(eventNamespace)
          ;
        },

        query: function() {

          // determine if an api event already occurred
          if(module.is.loading() && !settings.allowMultiple) {
            module.debug('Request cancelled previous request is still pending');
            return;
          }

          // pass element metadata to url (value, text)
          if(settings.defaultData) {
            $.extend(true, settings.urlData, module.get.defaultData());
          }

          // Add form content
          if(settings.serializeForm) {
            $.extend(true, settings.data, module.get.formData());
          }

          // call beforesend and get any settings changes
          requestSettings = module.get.settings();

          // check if beforesend cancelled request
          if(requestSettings === false) {
            module.error(error.beforeSend);
            return;
          }

          if(settings.url) {
            // override with url if specified
            module.debug('Using specified url', url);
            url = module.add.urlData( settings.url );
          }
          else {
            // otherwise find url from api endpoints
            url = module.add.urlData( module.get.templateURL() );
            module.debug('API url resolved to', url);
          }

          // exit conditions reached, missing url parameters
          if( !url ) {
            module.error(error.missingURL);
            return;
          }

          // add loading state
          module.set.loading();

          // look for jQuery ajax parameters in settings
          ajaxSettings = $.extend(true, {}, settings, {
            type       : settings.method || settings.type,
            data       : data,
            url        : url,
            beforeSend : settings.beforeXHR,
            success    : function() {},
            failure    : function() {},
            complete   : function() {}
          });

          module.verbose('Creating AJAX request with settings', ajaxSettings);

          // request provides a wrapper around xhr
          module.request = module.create.request();
          module.xhr = module.create.xhr();

        },


        is: {
          loading: function() {
            return (module.request && module.request.state() == 'pending');
          }
        },

        was: {
          succesful: function() {
            return (module.request && module.request.state() == 'resolved');
          },
          failure: function() {
            return (module.request && module.request.state() == 'rejected');
          },
          complete: function() {
            return (module.request && (module.request.state() == 'resolved' || module.request.state() == 'rejected') );
          }
        },

        add: {
          urlData: function(url, urlData) {
            var
              urlVariables
            ;
            if(url) {
              urlVariables = url.match(settings.regExpTemplate);
              urlData      = urlData || settings.urlData;

              if(urlVariables) {
                module.debug('Looking for URL variables', urlVariables);
                $.each(urlVariables, function(index, templateValue){
                  var
                    term      = templateValue.substr( 2, templateValue.length - 3),
                    termValue = ($.isPlainObject(urlData) && urlData[term] !== undefined)
                      ? urlData[term]
                      : ($module.data(term) !== undefined)
                        ? $module.data(term)
                        : urlData[term]
                  ;
                  module.verbose('Looking for variable', term);
                  // remove optional value
                  if(termValue === false) {
                    module.debug('Removing variable from URL', urlVariables);
                    url = url.replace('/' + templateValue, '');
                  }
                  // undefined condition
                  else if(termValue === undefined || !termValue) {
                    module.error(error.missingParameter, term, url);
                    url = false;
                    return false;
                  }
                  else {
                    url = url.replace(templateValue, termValue);
                  }
                });
              }
            }
            return url;
          }
        },

        event: {
          xhr: {
            always: function() {
              // calculate if loading time was below minimum threshold
            },
            done: function(response) {
              var
                context      = this,
                elapsedTime  = (new Date().getTime() - time),
                loadingDelay = (settings.loadingDuration - elapsedTime >= 0)
                  ? settings.loadingDuration - elapsedTime
                  : 0
              ;
              setTimeout(function(){
                module.request.resolveWith(context, [response]);
              }, loadingDelay);
            },
            fail: function(xhr, status, httpMessage) {
              var
                context      = this,
                elapsedTime  = (new Date().getTime() - time),
                loadingDelay = (settings.loadingDuration - elapsedTime >= 0)
                  ? settings.loadingDuration - elapsedTime
                  : 0
              ;
              // page triggers abort on navigation, dont show error
              if(status !== 'abort') {
                setTimeout(function(){
                  module.request.rejectWith(context, [xhr, status, httpMessage]);
                }, settings.loadingDelay);
              }
              else {
                module.reset();
              }
            }
          },
          request: {
            complete: function() {
              module.remove.loading();
              $.proxy(settings.complete, $context)();
            },
            done: function(response) {
              module.debug('API request received', response);
              if(settings.dataType == 'json') {
                if( $.isFunction(settings.successTest) ) {
                  module.debug('Checking JSON', settings.successTest, response);
                  if( settings.success(response) ) {
                    $.proxy(settings.success, $context)(response, $module);
                  }
                  else {
                    module.debug('JSON test specified by user and response failed', response);
                    $.proxy(settings.failure, $context)(response, $module);
                  }
                }
                else {
                  $.proxy(settings.success, $context)(response, $module);
                }
              }
              else {
                $.proxy(settings.success, $context)(response, $module);
              }
            },
            error: function(xhr, status, httpMessage) {
              var
                errorMessage = (settings.error[status] !== undefined)
                  ? settings.error[status]
                  : httpMessage,
                response
              ;
              // let em know unless request aborted
              if(xhr !== undefined) {
                // readyState 4 = done, anything less is not really sent
                if(xhr.readyState !== undefined && xhr.readyState == 4) {

                  // if http status code returned and json returned error, look for it
                  if( xhr.status != 200 && httpMessage !== undefined && httpMessage !== '') {
                    module.error(error.statusMessage + httpMessage);
                  }
                  else {
                    if(status == 'error' && settings.dataType == 'json') {
                      try {
                        response = $.parseJSON(xhr.responseText);
                        if(response && response.error !== undefined) {
                          errorMessage = response.error;
                        }
                      }
                      catch(er) {
                        module.error(error.JSONParse);
                      }
                    }
                  }
                  module.remove.loading();
                  module.set.error();
                  // show error state only for duration specified in settings
                  if(settings.errorDuration) {
                    setTimeout(module.remove.error, settings.errorDuration);
                  }
                  module.debug('API Request error:', errorMessage);
                  $.proxy(settings.failure, $context)(errorMessage, this);
                }
                else {
                  module.debug('Request Aborted (Most likely caused by page change)');
                }
              }
            }
          }
        },

        create: {
          request: function() {
            return $.Deferred()
              .always(module.event.request.complete)
              .done(module.event.request.done)
              .fail(module.event.request.error)
            ;
          },
          xhr: function() {
            $.ajax(ajaxSettings)
              .always(module.event.xhr.always)
              .done(module.event.xhr.done)
              .fail(module.event.xhr.fail)
            ;
          }
        },

        set: {
          error: function() {
            module.verbose('Adding error state to element', $context);
            $context.addClass(className.error);
          },
          loading: function() {
            module.verbose('Adding loading state to element', $context);
            $context.addClass(className.loading);
          }
        },

        remove: {
          error: function() {
            module.verbose('Removing error state from element', $context);
            $context.removeClass(className.error);
          },
          loading: function() {
            module.verbose('Removing loading state from element', $context);
            $context.removeClass(className.loading);
          }
        },

        get: {
          request: function() {
            return module.request;
          },
          xhr: function() {
            return module.xhr;
          },
          settings: function() {
            return $.proxy(settings.beforeSend, $module)(settings);
          },
          defaultData: function() {
            var
              data = {}
            ;
            if( !$.isWindow(element) ) {
              if( $module.is('input') ) {
                data.value = $module.val();
              }
              else {
                data.text = $module.text();
              }
            }
            return data;
          },
          event: function() {
            if( $.isWindow(element) || settings.on == 'now' ) {
              module.debug('API called without element, no events attached');
              return false;
            }
            else if(settings.on == 'auto') {
              if( $module.is('input') ) {
                return (element.oninput !== undefined)
                  ? 'input'
                  : (element.onpropertychange !== undefined)
                    ? 'propertychange'
                    : 'keyup'
                ;
              }
              else {
                return 'click';
              }
            }
            else {
              return settings.on;
            }
          },
          formData: function() {
            var
              formData
            ;
            if( $(this).toJSON() === undefined ) {
              module.error(error.missingSerialize);
              return;
            }
            formData = $form.toJSON();
            module.debug('Retrieving form data', formData);
            return $form.toJSON();
          },
          templateURL: function(action) {
            var
              url
            ;
            action = action || $module.data(settings.metadata.action) || settings.action || false;
            if(action) {
              module.debug('Looking up url for action', action);
              if(settings.api[action] !== undefined) {
                url = settings.api[action];
                module.debug('Found template url', url);
              }
              else {
                module.error(error.missingAction, settings.action);
              }
            }
            return url;
          }
        },

        // reset state
        reset: function() {
          module.remove.error();
          module.remove.loading();
        },

        setting: function(name, value) {
          if( $.isPlainObject(name) ) {
            $.extend(true, settings, name);
          }
          else if(value !== undefined) {
            settings[name] = value;
          }
          else {
            return settings[name];
          }
        },
        internal: function(name, value) {
          if( $.isPlainObject(name) ) {
            $.extend(true, module, name);
          }
          else if(value !== undefined) {
            module[name] = value;
          }
          else {
            return module[name];
          }
        },
        debug: function() {
          if(settings.debug) {
            if(settings.performance) {
              module.performance.log(arguments);
            }
            else {
              module.debug = Function.prototype.bind.call(console.info, console, settings.name + ':');
              module.debug.apply(console, arguments);
            }
          }
        },
        verbose: function() {
          if(settings.verbose && settings.debug) {
            if(settings.performance) {
              module.performance.log(arguments);
            }
            else {
              module.verbose = Function.prototype.bind.call(console.info, console, settings.name + ':');
              module.verbose.apply(console, arguments);
            }
          }
        },
        error: function() {
          module.error = Function.prototype.bind.call(console.error, console, settings.name + ':');
          module.error.apply(console, arguments);
        },
        performance: {
          log: function(message) {
            var
              currentTime,
              executionTime,
              previousTime
            ;
            if(settings.performance) {
              currentTime   = new Date().getTime();
              previousTime  = time || currentTime;
              executionTime = currentTime - previousTime;
              time          = currentTime;
              performance.push({
                'Element'        : element,
                'Name'           : message[0],
                'Arguments'      : [].slice.call(message, 1) || '',
                'Execution Time' : executionTime
              });
            }
            clearTimeout(module.performance.timer);
            module.performance.timer = setTimeout(module.performance.display, 100);
          },
          display: function() {
            var
              title = settings.name + ':',
              totalTime = 0
            ;
            time = false;
            clearTimeout(module.performance.timer);
            $.each(performance, function(index, data) {
              totalTime += data['Execution Time'];
            });
            title += ' ' + totalTime + 'ms';
            if(moduleSelector) {
              title += ' \'' + moduleSelector + '\'';
            }
            if( (console.group !== undefined || console.table !== undefined) && performance.length > 0) {
              console.groupCollapsed(title);
              if(console.table) {
                console.table(performance);
              }
              else {
                $.each(performance, function(index, data) {
                  console.log(data['Name'] + ': ' + data['Execution Time']+'ms');
                });
              }
              console.groupEnd();
            }
            performance = [];
          }
        },
        invoke: function(query, passedArguments, context) {
          var
            maxDepth,
            found,
            response
          ;
          passedArguments = passedArguments || queryArguments;
          context         = element         || context;
          if(typeof query == 'string' && instance !== undefined) {
            query    = query.split(/[\. ]/);
            maxDepth = query.length - 1;
            $.each(query, function(depth, value) {
              var camelCaseValue = (depth != maxDepth)
                ? value + query[depth + 1].charAt(0).toUpperCase() + query[depth + 1].slice(1)
                : query
              ;
              if( $.isPlainObject( instance[value] ) && (depth != maxDepth) ) {
                instance = instance[value];
              }
              else if( $.isPlainObject( instance[camelCaseValue] ) && (depth != maxDepth) ) {
                instance = instance[camelCaseValue];
              }
              else if( instance[value] !== undefined ) {
                found = instance[value];
                return false;
              }
              else if( instance[camelCaseValue] !== undefined ) {
                found = instance[camelCaseValue];
                return false;
              }
              else {
                module.error(error.method, query);
                return false;
              }
            });
          }
          if ( $.isFunction( found ) ) {
            response = found.apply(context, passedArguments);
          }
          else if(found !== undefined) {
            response = found;
          }
          if($.isArray(returnedValue)) {
            returnedValue.push(response);
          }
          else if(returnedValue !== undefined) {
            returnedValue = [returnedValue, response];
          }
          else if(response !== undefined) {
            returnedValue = response;
          }
          return found;
        }
      };

      if(methodInvoked) {
        if(instance === undefined) {
          module.initialize();
        }
        module.invoke(query);
      }
      else {
        if(instance !== undefined) {
          module.destroy();
        }
        module.initialize();
      }
    })
  ;

  return (returnedValue !== undefined)
    ? returnedValue
    : this
  ;
};

$.api.settings = {

  name            : 'API',
  namespace       : 'api',

  debug           : true,
  verbose         : true,
  performance     : true,

  // event binding
  on              : 'auto',
  filter          : '.disabled, .loading',
  context         : false,
  stateContext    : false,

  // templating
  action          : false,
  regExpTemplate  : /\{\$([A-z]+)\}/g,

  // data
  url             : false,
  urlData         : false,
  serializeForm   : false,

  // ui
  defaultData     : true,
  throttle        : 100,
  allowMultiple   : false,

  // state
  loadingDuration : 1000,
  errorDuration   : 2000,

  // jQ ajax
  method          : 'get',
  data            : {},
  dataType        : 'json',
  cache         : true,

  // callbacks
  beforeSend   : function(settings) { return settings; },
  beforeXHR    : function(xhr) {},

  success      : function(response) {},
  successText  : function(response) { return true; },
  complete     : function(response) {},
  failure      : function(response) {},

  // errors
  error : {
    beforeSend       : 'The before send function has aborted the request',
    error            : 'There was an error with your request',
    exitConditions   : 'API Request Aborted. Exit conditions met',
    JSONParse        : 'JSON could not be parsed during error handling',
    missingSerialize : 'Serializing a Form requires toJSON to be included',
    missingAction    : 'API action used but no url was defined',
    missingParameter : 'Missing an essential URL parameter: ',
    missingURL       : 'No URL specified for api event',
    parseError       : 'There was an error parsing your request',
    statusMessage    : 'Server gave an error: ',
    timeout          : 'Your request timed out'
  },

  className: {
    loading : 'loading',
    error   : 'error'
  },

  selector: {
    form: 'form'
  },

  metadata: {
    action  : 'action',
    request : 'request',
    xhr     : 'xhr'
  }
};


$.api.settings.api = {};


})( jQuery, window , document );