/*
 * jQuery File Upload Processing Plugin
 * https://github.com/blueimp/jQuery-File-Upload
 *
 * Copyright 2012, Sebastian Tschan
 * https://blueimp.net
 *
 * Licensed under the MIT license:
 * https://opensource.org/licenses/MIT
 */

/* global define, require */

(function(factory) {
  'use strict';
  if (typeof define === 'function' && define.amd) {
    // Register as an anonymous AMD module:
    define(['jquery', './jquery.fileupload'], factory);
  } else if (typeof exports === 'object') {
    // Node/CommonJS:
    factory(require('jquery'), require('./jquery.fileupload'));
  } else {
    // Browser globals:
    factory(window.jQuery);
  }
})(function($) {
  'use strict';

  var originalAdd = $.blueimp.fileupload.prototype.options.add;

  // The File Upload Processing plugin extends the fileupload widget
  // with file processing functionality:
  $.widget('blueimp.fileupload', $.blueimp.fileupload, {
    options: {
      // The list of processing actions:
      processQueue: [
        /*
                {
                    action: 'log',
                    type: 'debug'
                }
                */
      ],
      add: function(e, data) {
        var $this = $(this);
        data.process(function() {
          return $this.fileupload('process', data);
        });
        originalAdd.call(this, e, data);
      }
    },

    processActions: {
      /*
            log: function (data, options) {
                console[options.type](
                    'Processing "' + data.files[data.index].name + '"'
                );
            }
            */
    },

    _processFile: function(data, originalData) {
      var that = this,
        // eslint-disable-next-line new-cap
        dfd = $.Deferred().resolveWith(that, [data]),
        chain = dfd.promise();
      this._trigger('process', null, data);
      $.each(data.processQueue, function(i, settings) {
        var func = function(data) {
          if (originalData.errorThrown) {
            // eslint-disable-next-line new-cap
            return $.Deferred()
              .rejectWith(that, [originalData])
              .promise();
          }
          return that.processActions[settings.action].call(
            that,
            data,
            settings
          );
        };
        chain = chain.then(func, settings.always && func);
      });
      chain
        .done(function() {
          that._trigger('processdone', null, data);
          that._trigger('processalways', null, data);
        })
        .fail(function() {
          that._trigger('processfail', null, data);
          that._trigger('processalways', null, data);
        });
      return chain;
    },

    // Replaces the settings of each processQueue item that
    // are strings starting with an "@", using the remaining
    // substring as key for the option map,
    // e.g. "@autoUpload" is replaced with options.autoUpload:
    _transformProcessQueue: function(options) {
      var processQueue = [];
      $.each(options.processQueue, function() {
        var settings = {},
          action = this.action,
          prefix = this.prefix === true ? action : this.prefix;
        $.each(this, function(key, value) {
          if ($.type(value) === 'string' && value.charAt(0) === '@') {
            settings[key] =
              options[
                value.slice(1) ||
                  (prefix
                    ? prefix + key.charAt(0).toUpperCase() + key.slice(1)
                    : key)
              ];
          } else {
            settings[key] = value;
          }
        });
        processQueue.push(settings);
      });
      options.processQueue = processQueue;
    },

    // Returns the number of files currently in the processsing queue:
    processing: function() {
      return this._processing;
    },

    // Processes the files given as files property of the data parameter,
    // returns a Promise object that allows to bind callbacks:
    process: function(data) {
      var that = this,
        options = $.extend({}, this.options, data);
      if (options.processQueue && options.processQueue.length) {
        this._transformProcessQueue(options);
        if (this._processing === 0) {
          this._trigger('processstart');
        }
        $.each(data.files, function(index) {
          var opts = index ? $.extend({}, options) : options,
            func = function() {
              if (data.errorThrown) {
                // eslint-disable-next-line new-cap
                return $.Deferred()
                  .rejectWith(that, [data])
                  .promise();
              }
              return that._processFile(opts, data);
            };
          opts.index = index;
          that._processing += 1;
          that._processingQueue = that._processingQueue
            .then(func, func)
            .always(function() {
              that._processing -= 1;
              if (that._processing === 0) {
                that._trigger('processstop');
              }
            });
        });
      }
      return this._processingQueue;
    },

    _create: function() {
      this._super();
      this._processing = 0;
      // eslint-disable-next-line new-cap
      this._processingQueue = $.Deferred()
        .resolveWith(this)
        .promise();
    }
  });
});
