EDIT

function CdmOpenlayersMap(mapElement, mapserverBaseUrl, mapserverVersion, options){

  var mapServicePath = '/edit_wp5';

  var legendImgSrc = null;

  var map = null;

  var dataBounds = null;

  var baseLayers = [];

  var defaultBaseLayer;

  var defaultControls = [

           new OpenLayers.Control.PanZoom(),

           new OpenLayers.Control.Navigation({zoomWheelEnabled: false, handleRightClicks:true, zoomBoxKeyMask: OpenLayers.Handler.MOD_CTRL})

         ];

  /*

   * EPSG:4326 and EPSG:900913 extends

   */

  var mapExtend_4326 = new OpenLayers.Bounds(-180, -90, 180, 90);

  var mapExtend_900913 = new OpenLayers.Bounds(-20037508.34, -20037508.34, 20037508.34, 20037508.34);

  var mapOptions={

      EPSG900913: {

        controls: defaultControls,

        maxExtent: mapExtend_900913,

        //maxResolution: (mapExtend_900913.getWidth() / options.displayWidth),

        maxResolution: (mapExtend_900913.getHeight() / (options.displayWidth / 2)),

        //maxResolution:156543.0339 * 20,

        units:'m',

        restrictedExtent: mapExtend_900913,

        projection: new OpenLayers.Projection("EPSG:900913")

      },

      EPSG4326: {

        controls: defaultControls,

        maxExtent: mapExtend_4326,

        maxResolution: (mapExtend_4326.getWidth() / options.displayWidth),

        units:'degrees',

        restrictedExtent: mapExtend_4326,

        projection: new OpenLayers.Projection("EPSG:4326")

      }

  };

  var dataProj = new OpenLayers.Projection("EPSG:4326");

  var dataLayerOptions = {

      maxExtent: mapExtend_900913,

      isBaseLayer: false,

      displayInLayerSwitcher: true

  };

  var layerByNameMap = {

      tdwg1: 'topp:tdwg_level_1',

      tdwg2: 'topp:tdwg_level_2',

      tdwg3: 'topp:tdwg_level_3',

      tdwg4: 'topp:tdwg_level_4'

  };

  /**

   *

   */

  this.init = function(){ // public function

    createLayers(options.baseLayerNames, options.defaultBaseLayerName);

     //HACK !!!!!!!!!!!!!!!!!!!!!!!!!!!!

    if(defaultBaseLayer.projection == mapOptions.EPSG900913.projection){

      options.minZoom = 1;

    }

    initOpenLayers();

    // -- Distribution Layer --

    var mapServiceRequest;

    var distributionQuery = mapElement.attr('distributionQuery');

    if(distributionQuery !== undefined){

      if(typeof legendPosition == 'number'){

        distributionQuery = mergeQueryStrings(distributionQuery, 'legend=1&mlp=' + options.legendPosition);

      }

      distributionQuery = mergeQueryStrings(distributionQuery, 'callback=?');

      var legendFormatQuery = mapElement.attr('legendFormatQuery');

      if(legendFormatQuery !== undefined){

        legendImgSrc = mergeQueryStrings('/GetLegendGraphic?SERVICE=WMS&VERSION=1.1.1', legendFormatQuery);

      }

      mapServiceRequest = mapserverBaseUrl + mapServicePath + '/' + mapserverVersion + '/areas.php?' + distributionQuery;

      jQuery.ajax({

          url: mapServiceRequest,

          dataType: "jsonp",

          success: function(data){

            addDataLayer(data);

          }

        });

    }

    // -- Occurrence Layer --

    var occurrenceQuery = mapElement.attr('occurrenceQuery');

    if(occurrenceQuery !== undefined){

//      if(typeof legendPosition == 'number'){

//        occurrenceQuery = mergeQueryStrings(distributionQuery, 'legend=1&mlp=' + options.legendPosition);

//      }

      occurrenceQuery = mergeQueryStrings(occurrenceQuery, 'callback=?');

//      var legendFormatQuery = mapElement.attr('legendFormatQuery');

//      if(legendFormatQuery !== undefined){

//        legendImgSrc = mergeQueryStrings('/GetLegendGraphic?SERVICE=WMS&VERSION=1.1.1', legendFormatQuery);

//      }

      mapServiceRequest = mapserverBaseUrl + mapServicePath + '/' + mapserverVersion + '/points.php?' + occurrenceQuery;

      jQuery.ajax({

          url: mapServiceRequest,

          dataType: "jsonp",

          success: function(data){

            addDataLayer(data);

          }

        });

    }

  };

  /**

   * Initialize the Openlayers viewer with the base layer

   */

  var initOpenLayers = function(){

    // instantiate the openlayers viewer

    if(defaultBaseLayer.projection == mapOptions.EPSG900913.projection){

      map = new OpenLayers.Map('openlayers_map', mapOptions.EPSG900913);

    } else {

      map = new OpenLayers.Map('openlayers_map', mapOptions.EPSG4326);

    }

    //add the base layers

    map.addLayers(baseLayers);

    map.setBaseLayer(defaultBaseLayer);

    if(options.showLayerSwitcher === true){

      map.addControl(new OpenLayers.Control.LayerSwitcher({'ascending':false}));

    }

    // zoom to the required area

    var boundsStr = (typeof options.boundingBox == 'string' && options.boundingBox.length > 6 ? options.boundingBox : '-180, -90, 180, 90');

    var zoomToBounds = OpenLayers.Bounds.fromString( boundsStr );

    map.zoomToExtent(zoomToBounds.transform(dataProj, map.getProjectionObject()), false);

    if(map.getZoom() > options.maxZoom){

      map.zoomTo(options.maxZoom);

    } else if(map.getZoom() < options.minZoom){

      map.zoomTo(options.minZoom);

    }

    // adjust height of openlayers container div

    jQuery('#openlayers').css('height', jQuery('#openlayers #openlayers_map').height());

  };

  /**

   * add a distribution layer

   */

  var addDataLayer = function(mapResponseObj){

    var layer;

    // add additional layers, get them from the mapResponseObj

    if(mapResponseObj !== undefined){

      if(mapResponseObj.points_sld !== undefined){

        // it is a response from the points.php

    	var geoserverUri;

    	if(mapResponseObj.geoserver) {

    		geoserverUri = mapResponseObj.geoserver;

    	} else {

    		// it is an old servive which is not providing the corresponding geoserver URI, so we guess it

    		geoserverUri = mapserverBaseUrl + "/geoserver/wms";

    	}

    	//TODO points_sld should be renamed to sld in response + fill path to sld should be given

        layer = new OpenLayers.Layer.WMS.Untiled(

            'points',

            geoserverUri,

            {layers: 'topp:rest_points' ,transparent:"true", format:"image/png"},

            dataLayerOptions );

        var sld = mapResponseObj.points_sld;

        if(sld.indexOf("http://") !== 0){

          // it is an old servive which is not providing the full sdl URI, so we guess it

          //  http://edit.africamuseum.be/synthesys/www/v1/sld/

          //  http://edit.br.fgov.be/synthesys/www/v1/sld/

          sld =  mapserverBaseUrl + "/synthesys/www/v1/sld/" + sld;

        }

        layer.params.SLD = sld;

        map.addLayers([layer]);

      } else {

        // it is a response from the areas.php

        for ( var i in mapResponseObj.layers) {

        var layerData = mapResponseObj.layers[i];

          layer = new OpenLayers.Layer.WMS.Untiled(

              layerData.tdwg,

              mapResponseObj.geoserver + "/wms",

              {layers: layerByNameMap[layerData.tdwg] ,transparent:"true", format:"image/png"},

              dataLayerOptions );

          layer.params.SLD = layerData.sld;

          layer.setOpacity(options.distributionOpacity);

          map.addLayers([layer]);

        }

      }

      // zoom to the required area

      if(mapResponseObj.bbox !== undefined){

        var newBounds =  OpenLayers.Bounds.fromString( mapResponseObj.bbox );

        if(dataBounds !== null){

          dataBounds.extend(newBounds);

        } else if(newBounds !== undefined){

          dataBounds = newBounds;

        }

        map.zoomToExtent(dataBounds.transform(dataProj, map.getProjectionObject()), false);

        if(map.getZoom() > options.maxZoom){

          map.zoomTo(options.maxZoom);

        } else if(map.getZoom() < options.minZoom){

          map.zoomTo(options.minZoom);

        }

      }

      if(options.legendPosition !== undefined && mapResponseObj.legend !== undefined){

        var legendSrcUrl = mapResponseObj.geoserver + legendImgSrc + mapResponseObj.legend;

        addLegendAsElement(legendSrcUrl);

        //addLegendAsLayer(legendSrcUrl, map);

      }

    }

  };

  /**

   *

   */

  var addLegendAsElement= function(legendSrcUrl){

    mapElement.after('<div class="openlayers_legend"><img src="' + legendSrcUrl + '"></div>');

    mapElement.next('.openlayers_legend').css('opacity', options.legendOpacity).find('img').load(function () {

      jQuery(this).parent()

        .css('position', 'relative')

        .css('z-index', '1002')

        .css('top', -mapElement.height())

        .css('left', mapElement.width()- jQuery(this).width())

        .width(jQuery(this).width());

    });

  };

  var addLegendAsLayer= function(legendSrcUrl, map){

    var w, h;

    // 1. download imge to find height and width

    mapElement.after('<div class="openlayers_legend"><img src="' + legendSrcUrl + '"></div>');

    mapElement.next('.openlayers_legend').css('display', 'none').css('opacity', options.legendOpacity).find('img').load(function () {

      w = mapElement.next('.openlayers_legend').find('img').width();

      h = mapElement.next('.openlayers_legend').find('img').height();

      mapElement.next('.openlayers_legend').remove();

//      createLegendLayer();

//      // 2. create the Legend Layer

      //TODO createLegendLayer as inner fiinction seems like an error

//      var createLegendLayer = function(){

//

//

//        var legendLayerOptions={

//            maxResolution: '.$maxRes.',

//            maxExtent: new OpenLayers.Bounds(0, 0, w, h)

//        };

//

//        var legendLayer = new OpenLayers.Layer.Image(

//            'Legend',

//            legendSrcUrl,

//            new OpenLayers.Bounds(0, 0, w, h),

//            new OpenLayers.Size(w, h),

//            imageLayerOptions);

//      };

    });

  };

  /**

   * merge 2 Url query strings

   */

   var mergeQueryStrings = function(queryStr1, queryStr2){

    if(queryStr1.charAt(queryStr1.length - 1) != '&'){

      queryStr1 += '&';

    }

    if(queryStr2.charAt(0) == '&'){

      return queryStr1 + queryStr2.substr(1);

    } else {

      return queryStr1 + queryStr2;

    }

   };

   /**

    *

    */

   var createLayers = function( baseLayerNames, defaultBaseLayerName){

     for(var i = 0; i <  baseLayerNames.length; i++) {

       baseLayers[i] = getLayersByName(baseLayerNames[i]);

       if(baseLayerNames[i] == defaultBaseLayerName){

         defaultBaseLayer = baseLayers[i];

       }

     }

   };

   /**

    * returns the version number contained in the version string:

    *   v1.1 --> 1.1

    *   v1.2_dev --> 1.2

    */

   var mapServerVersionNumber = function() {

	   var pattern = /v([\d\.]+).*$/;

	   var result;

	   if (result = mapserverVersion.match(pattern) !== null) {

		   return result[0];

	   } else {

		   return null;

	   }

   }

  /**

   *

   */

  var getLayersByName = function(layerName){

    var baseLayer = null;

    switch(layerName){

      case 'metacarta_vmap0':

        /**

         * NOTE: labs.metacarta.com is currently unavailable

         *

         * Available Projections:

         *     EPSG:900913

         *     EPSG:4326

         */

        baseLayer = new OpenLayers.Layer.WMS(

              "Metacarta Vmap0",

              "http://labs.metacarta.com/wms/vmap0",

              {layers: 'basic', format:"png"},

              {

              maxExtent: mapExtend_4326,

              isBaseLayer: true,

              displayInLayerSwitcher: true

            }

        );

      break;

      case 'osgeo_vmap0':

        /**

         * Available Projections:

         *     EPSG:4269

              EPSG:4326

              EPSG:900913

         */

        baseLayer = new OpenLayers.Layer.WMS(

              "Metacarta Vmap0",

              "http://vmap0.tiles.osgeo.org/wms/vmap0",

              {layers: 'basic', format:"png"},

              {

            maxExtent: mapExtend_900913,

            isBaseLayer: true,

            displayInLayerSwitcher: true

          }

        );

      break;

      case 'edit-etopo1':

        baseLayer = new OpenLayers.Layer.WMS(

              "ETOPO1 Global Relief Model",

              "http://edit.br.fgov.be:8080/geoserver/wms",

              {layers: 'topp:color_etopo1_ice_full', format:"image/png"},

              {

            maxExtent: mapExtend_900913,

            isBaseLayer: true,

            displayInLayerSwitcher: true

          }

        );

      break;

      case 'edit-vmap0_world_basic':

        baseLayer = new OpenLayers.Layer.WMS(

              "EDIT Vmap0",

              "http://edit.br.fgov.be:8080/geoserver/wms",

              {layers: 'vmap0_world_basic', format:"image/png"},

              {

            maxExtent: mapExtend_900913,

            isBaseLayer: true,

            displayInLayerSwitcher: true

          }

        );

      break;

      // create Google Mercator layers

      case 'gmap':

        baseLayer = new OpenLayers.Layer.Google(

                  "Google Streets",

                  {'sphericalMercator': true}

              );

      break;

      case 'gsat':

        baseLayer = new OpenLayers.Layer.Google(

                  "Google Satellite",

                  {type: G_SATELLITE_MAP, 'sphericalMercator': true, numZoomLevels: 22}

              );

      break;

      case 'ghyb':

        baseLayer = new OpenLayers.Layer.Google(

                  "Google Hybrid",

                  {type: G_HYBRID_MAP, 'sphericalMercator': true}

              );

      break;

      case 'veroad':

        baseLayer = new OpenLayers.Layer.VirtualEarth(

                  "Virtual Earth Roads",

                  {'type': VEMapStyle.Road, 'sphericalMercator': true}

              );

      break;

      case 'veaer':

        baseLayer = new OpenLayers.Layer.VirtualEarth(

                  "Virtual Earth Aerial",

                  {'type': VEMapStyle.Aerial, 'sphericalMercator': true}

              );

      break;

      case 'vehyb':

        baseLayer = new OpenLayers.Layer.VirtualEarth(

                  "Virtual Earth Hybrid",

                  {'type': VEMapStyle.Hybrid, 'sphericalMercator': true}

              );

      break;

      case 'yahoo':

        baseLayer = new OpenLayers.Layer.Yahoo(

                  "Yahoo Street",

                  {'sphericalMercator': true}

              );

      break;

      case 'yahoosat':

        baseLayer = new OpenLayers.Layer.Yahoo(

                  "Yahoo Satellite",

                  {'type': YAHOO_MAP_SAT, 'sphericalMercator': true}

              );

      break;

      case 'yahoohyb':

         rebaseLayer = new OpenLayers.Layer.Yahoo(

                  "Yahoo Hybrid",

                  {'type': YAHOO_MAP_HYB, 'sphericalMercator': true}

              );

      break;

      case 'mapnik':

        baseLayer = new OpenLayers.Layer.OSM();

      break;

      case 'oam':

        baseLayer = new OpenLayers.Layer.XYZ(

                "OpenAerialMap",

                "http://tile.openaerialmap.org/tiles/1.0.0/openaerialmap-900913/${z}/${x}/${y}.png",

                {

                    sphericalMercator: true

                }

            );

      break;

      case 'osmarender':

        baseLayer = new OpenLayers.Layer.OSM(

                "OpenStreetMap (Tiles@Home)",

                "http://tah.openstreetmap.org/Tiles/tile/${z}/${x}/${y}.png"

               );

      break;

    }

    return baseLayer;

  };

}

(function($){

  $.fn.cdm_openlayers_map = function(mapserverBaseUrl, mapserverVersion, options) {

    var opts = $.extend({},$.fn.cdm_openlayers_map.defaults, options);

    return this.each(function(){

      var openlayers_map = new CdmOpenlayersMap($(this), mapserverBaseUrl, mapserverVersion, opts);

      openlayers_map.init();

     }); // END each

  }; // END cdm_openlayers_map

})(jQuery);

(function($){

$.fn.cdm_openlayers_map.defaults = {  // set up default options

    legendPosition:  null,      // 1,2,3,4,5,6 = display a legend in the corner specified by the number

    displayWidth: 400,

    distributionOpacity: 0.75,

    legendOpacity: 0.75,

    boundingBox: null,

    showLayerSwitcher: false,

    baseLayerNames: ["osgeo_vmap0"],

    defaultBaseLayerName: 'osgeo_vmap0',

    maxZoom: 4,

    minZoom: 0

};

})(jQuery);