(function ($, DataTable) {
  "use strict";

  var _buildParams = function (dt, action, onlyVisibles) {
    var params = dt.ajax.params();
    params.action = action;
    params._token = $('meta[name="csrf-token"]').attr('content');

    if (onlyVisibles) {
      params.visible_columns = _getVisibleColumns();
    } else {
      params.visible_columns = null;
    }

    return params;
  };

  var _getVisibleColumns = function () {

    var visible_columns = [];
    $.each(DataTable.settings[0].aoColumns, function (key, col) {
      if (col.bVisible) {
        visible_columns.push(col.name);
      }
    });

    return visible_columns;
  };

  var _formatUrlForExport = function (url) {
    if (url.indexOf('?') === -1) {
      return url;
    }

    var route = url.split('?');
    var output = route[0];

    if (route[0].charAt(route[0].length-1) !== '/') {
      output += '/';
    }
    output += 'export/?' + route[1].replace('/export', '');

    return output;
  };

  var _downloadFromUrl = function (url, params) {
    var postUrl = _formatUrlForExport(url);
    var xhr = new XMLHttpRequest();
    xhr.open('POST', postUrl, true);
    xhr.responseType = 'arraybuffer';
    xhr.onload = function () {
      if (this.status === 200) {
        var filename = "";
        var disposition = xhr.getResponseHeader('Content-Disposition');
        if (disposition && disposition.indexOf('attachment') !== -1) {
          var filenameRegex = /filename[^;=\n]*=((['"]).*?\2|[^;\n]*)/;
          var matches = filenameRegex.exec(disposition);
          if (matches != null && matches[1]) filename = matches[1].replace(/['"]/g, '');
        }
        var type = xhr.getResponseHeader('Content-Type');

        var blob = new Blob([this.response], {type: type});
        if (typeof window.navigator.msSaveBlob !== 'undefined') {
          // IE workaround for "HTML7007: One or more blob URLs were revoked by closing the blob for which they were created. These URLs will no longer resolve as the data backing the URL has been freed."
          window.navigator.msSaveBlob(blob, filename);
        } else {
          var URL = window.URL || window.webkitURL;
          var downloadUrl = URL.createObjectURL(blob);

          if (filename) {
            // use HTML5 a[download] attribute to specify filename
            var a = document.createElement("a");
            // safari doesn't support this yet
            if (typeof a.download === 'undefined') {
              window.location = downloadUrl;
            } else {
              a.href = downloadUrl;
              a.download = filename;
              document.body.appendChild(a);
              a.click();
            }
          } else {
            window.location = downloadUrl;
          }

          setTimeout(function () {
            URL.revokeObjectURL(downloadUrl);
          }, 100); // cleanup
        }
      }
    };
    xhr.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
    xhr.send($.param(params));
  };

  var _buildUrl = function(dt, action) {
    var url = dt.ajax.url() || '';
    var params = dt.ajax.params();
    params.action = action;

    if (url.indexOf('?') > -1) {
      return url + '&' + $.param(params);
    }

    return url + '?' + $.param(params);
  };

  DataTable.ext.buttons.excel = {
    className: 'buttons-excel',

    text: function (dt) {
      return '<i class="fa fa-file-excel-o"></i> ' + dt.i18n('buttons.excel', 'Excel');
    },

    action: function (e, dt, button, config) {
      var url = _buildUrl(dt, 'excel');
      window.location = url;
    }
  };

  DataTable.ext.buttons.postExcel = {
    className: 'buttons-excel',

    text: function (dt) {
      return '<i class="fa fa-file-excel-o"></i> ' + dt.i18n('buttons.excel', 'Excel');
    },

    action: function (e, dt, button, config) {
      var url = dt.ajax.url() || window.location.href;
      var params = _buildParams(dt, 'excel');

      _downloadFromUrl(url, params);
    }
  };

  DataTable.ext.buttons.postExcelVisibleColumns = {
    className: 'buttons-excel',

    text: function (dt) {
      return '<i class="fa fa-file-excel-o"></i> ' + dt.i18n('buttons.excel', 'Excel (only visible columns)');
    },

    action: function (e, dt, button, config) {
      var url = dt.ajax.url() || window.location.href;
      var params = _buildParams(dt, 'excel', true);

      _downloadFromUrl(url, params);
    }
  };

  DataTable.ext.buttons.export = {
    extend: 'collection',

    className: 'buttons-export',

    text: function (dt) {
      return '<i class="fa fa-download"></i> ' + dt.i18n('buttons.export', 'Export') + '&nbsp;<span class="caret"/>';
    },

    buttons: ['csv', 'excel', 'pdf']
  };

  DataTable.ext.buttons.csv = {
    className: 'buttons-csv',

    text: function (dt) {
      return '<i class="fa fa-file-excel-o"></i> ' + dt.i18n('buttons.csv', 'CSV');
    },

    action: function (e, dt, button, config) {
      var url = _buildUrl(dt, 'csv');
      window.location = url;
    }
  };

  DataTable.ext.buttons.postCsvVisibleColumns = {
    className: 'buttons-csv',

    text: function (dt) {
      return '<i class="fa fa-file-excel-o"></i> ' + dt.i18n('buttons.csv', 'CSV (only visible columns)');
    },

    action: function (e, dt, button, config) {
      var url = dt.ajax.url() || window.location.href;
      var params = _buildParams(dt, 'csv', true);

      _downloadFromUrl(url, params);
    }
  };

  DataTable.ext.buttons.postCsv = {
    className: 'buttons-csv',

    text: function (dt) {
      return '<i class="fa fa-file-excel-o"></i> ' + dt.i18n('buttons.csv', 'CSV');
    },

    action: function (e, dt, button, config) {
      var url = dt.ajax.url() || window.location.href;
      var params = _buildParams(dt, 'csv');

      _downloadFromUrl(url, params);
    }
  };

  DataTable.ext.buttons.pdf = {
    className: 'buttons-pdf',

    text: function (dt) {
      return '<i class="fa fa-file-pdf-o"></i> ' + dt.i18n('buttons.pdf', 'PDF');
    },

    action: function (e, dt, button, config) {
      var url = _buildUrl(dt, 'pdf');
      window.location = url;
    }
  };

  DataTable.ext.buttons.postPdf = {
    className: 'buttons-pdf',

    text: function (dt) {
      return '<i class="fa fa-file-pdf-o"></i> ' + dt.i18n('buttons.pdf', 'PDF');
    },

    action: function (e, dt, button, config) {
      var url = dt.ajax.url() || window.location.href;
      var params = _buildParams(dt, 'pdf');

      _downloadFromUrl(url, params);
    }
  };

  DataTable.ext.buttons.print = {
    className: 'buttons-print',

    text: function (dt) {
      return  '<i class="fa fa-print"></i> ' + dt.i18n('buttons.print', 'Print');
    },

    action: function (e, dt, button, config) {
      var url = _buildUrl(dt, 'print');
      window.location = url;
    }
  };

  DataTable.ext.buttons.reset = {
    className: 'buttons-reset',

    text: function (dt) {
      return '<i class="fa fa-undo"></i> ' + dt.i18n('buttons.reset', 'Reset');
    },

    action: function (e, dt, button, config) {
      dt.search('');
      dt.columns().search('');
      dt.draw();
    }
  };

  DataTable.ext.buttons.reload = {
    className: 'buttons-reload',

    text: function (dt) {
      return '<i class="fa fa-refresh"></i> ' + dt.i18n('buttons.reload', 'Reload');
    },

    action: function (e, dt, button, config) {
      dt.draw(false);
    }
  };

  DataTable.ext.buttons.create = {
    className: 'buttons-create',

    text: function (dt) {
      return '<i class="fa fa-plus"></i> ' + dt.i18n('buttons.create', 'Create');
    },

    action: function (e, dt, button, config) {
      window.location = window.location.href.replace(/\/+$/, "") + '/create';
    }
  };

  if (typeof DataTable.ext.buttons.copyHtml5 !== 'undefined') {
    $.extend(DataTable.ext.buttons.copyHtml5, {
      text: function (dt) {
        return '<i class="fa fa-copy"></i> ' + dt.i18n('buttons.copy', 'Copy');
      }
    });
  }

  if (typeof DataTable.ext.buttons.colvis !== 'undefined') {
    $.extend(DataTable.ext.buttons.colvis, {
      text: function (dt) {
        return '<i class="fa fa-eye"></i> ' + dt.i18n('buttons.colvis', 'Column visibility');
      }
    });
  }
})(jQuery, jQuery.fn.dataTable);
