//var endpoint = "http://dblp.l3s.de/d2r/sparql";
	var tamany_pagina = 15;
	
	function mostraErrors(xhr, textStatus, errorThrown) {
      /* Funció que mostra l'error en la consulta */
	   alert(textStatus);
        console.log(errorThrown);
    }
		
    function consulta_SPARQL_JSON(queryStr, tipus_consulta,urlrepo) {
      var querypart = "query=" + escape(queryStr);
    /* Funció que llança la conuslta per AJAX al repositori i espera la resposata o fallida de la mateixa */ 
       $.ajax({
            xhrFields: {
			  withCredentials: true
			},
			url: urlrepo,
            type: 'POST',
			data: querypart,
            dataType: 'json',
			crossDomain: true,
            headers: {
                'Content-type': 'application/x-www-form-urlencoded',
                'Accept': 'application/sparql-results+json'
            },
            contentType: 'application/json; charset=utf-8',
            success: function(data){
				tractaResposta(data, tipus_consulta)
			},
            error: mostraErrors            
        });	  
    };
	
  function tractaResposta(jsonObj,tipus_consulta) {
	/* Funció que tracta el resultat de la resposta a la consulta SPARQL depenent del tipu de consulta*/
	  switch(tipus_consulta) {
        case "cerca_biblio_autor":		
        // Build up a table of results.
        var autors="";
		var anticpub="";
		var autor="";
		var nompub="";
		var datapub="";
		var pub="";
		var num=0;
		var result = " <table border='2' cellpadding='9' class='table-striped table-condensed'>" ;
        var numres=0;
		var primer=true;
		result += "<thead><tr><th colspan=2>Publicacions</th></thead><tbody>";
		for(var i = 0; i<  jsonObj.results.bindings.length; i++) {
		  
		  numres++;         
		  pub=jsonObj.results.bindings[i]["pub"].value;
		  
          if (anticpub!=pub){
			if (anticpub!=""){  // no es primer elemento hay que escribir el elemento anterior
			  result+="<tr><td>"+num+"</td><td>"+autors+".("+datapub+").<b>"+nompub+".</b></td></tr>";
			}
			num=num+1;
			autor=jsonObj.results.bindings[i]["nomautor"].value;
            nompub=jsonObj.results.bindings[i]["nompub"].value;
            datapub=jsonObj.results.bindings[i]["datapub"].value;
			autors=autor;
			anticpub=pub;			
		  }else{
			autor=jsonObj.results.bindings[i]["nomautor"].value;
			autors+=","+autor;  
		  }
		}
		//escribir ultimo elemento
		result+="<tr><td>"+num+"</td><td>"+autors+".("+datapub+").<b>"+nompub+".</b></td></tr>";
		result += "</tbody></table><br>" ;
		if (numres>0){
          document.getElementById("results").innerHTML = result;
		}else{
		  document.getElementById("results").innerHTML = "No existeix camp resultat per a la consulta realitzada.";
		}
		break;
	  default:  // Consulta no reconeguda
        alert("Consulta no reconeguda");
      }
	}
         
  function construeix_query(tipus_consulta, offset, urlrepo){
	/* Segons el tipus de consulta, construeix un tipus de consulta SPARQL o un altra */	
	switch(tipus_consulta) {
      case "cerca_biblio_autor":
        var autor= document.getElementById("autorsearched").value;
		var query= [
		" PREFIX swrc: <http://swrc.ontoware.org/ontology#> ",
		" PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> ",
		" PREFIX owl: <http://www.w3.org/2002/07/owl#> ",
		" PREFIX d2r: <http://sites.wiwiss.fu-berlin.de/suhl/bizer/d2r-server/config.rdf#> ",
		" PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> ",
		" PREFIX dcterms: <http://purl.org/dc/terms/> ",
		" PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> ",
		" PREFIX map: <file:///home/diederich/d2r-server-0.3.2/dblp-mapping.n3#> ",
		" PREFIX foaf: <http://xmlns.com/foaf/0.1/> ",
		" PREFIX dc: <http://purl.org/dc/elements/1.1/> ",
		" SELECT (Str(?name2) as ?nomautor) (Str(?pubname) as ?nompub) (Str(?date) as ?datapub) ?pub ",
        "   WHERE{ ",
        "     ?autor2 foaf:name ?name2 . ",
        "     ?pub dc:creator ?autor2 . ",
        "     ?pub dcterms:issued ?date . ",
	    "     ?pub dc:title ?pubname . ",
        "     {  ",
        "      SELECT  DISTINCT ?pub  ",
	    "  WHERE { ",
		"   ?pub dc:creator ?autor . ",
		"   ?autor foaf:name ?name . ",
        " FILTER regex(str(?name), '"+autor+"', 'i') .",
		//" FILTER regex(str(?name), '^"+autor+"', 'i') .",
	    "  }ORDER BY ?pub ",
	    "  OFFSET "+offset+" ", 
	    "  LIMIT  "+tamany_pagina+" ", 
        "    } ",
        "  }ORDER BY ?pub ?autor2 "
		
		/*
		" SELECT Str(?name) Str(?pubname) Str(?date) ?pub",
		"  WHERE {",
		"    ?pub dc:creator ?autor . ",
		"    ?pub dc:title ?pubname . ",
		"    ?pub dcterms:issued ?date . ",
		"    ?autor foaf:name ?name . ",
		"    FILTER regex(?name, '"+autor+"', 'i') .",
		"  }",
		"  ORDER BY ASC(?name) ASC(?date) ASC(?pubname)  ",
		"  OFFSET "+offset+" ",
		"  LIMIT  "+tamany_pagina+" ",
		*/
		
		].join(" ");
	    return query;
      default:  // Consulta no reconeguda
        return false;
	}
  }
  
  
  function Consultar(offset){
	/* Funció de cerca al pitjar el botó, mira el tipus de consulta seleccionat i crida a montra la query i llançar-la si tot es correcte */
	var tipus_consulta = document.getElementById("llistacerques").value;
	var urlrepo = document.getElementById("llistarepositori").value;	 
	document.getElementById("results").innerHTML = "<br><div class='message' align='center'>En uns instants apareixeran els resultats de la consulta</div><br><div class='loader'>Loading...</div>";
 	var query = construeix_query(tipus_consulta,offset,urlrepo);
	if(query){		
	  consulta_SPARQL_JSON(query, tipus_consulta,urlrepo);
	}else{
	  alert("Consulta: "+tipus_consulta+" no reconeguda.");
	}
  }
  
  
  /*
  
  SELECT Str(?name) Str(?pubname) Str(?date) ?pub
		 WHERE {
		    ?pub dc:creator ?autor . 
		    ?pub dc:title ?pubname . 
		    ?pub dcterms:issued ?date . 
		    ?autor foaf:name ?name . 
		    FILTER regex(?name, 'James', 'i') .
		  }
		  ORDER BY ASC(?name) ASC(?date) ASC(?pubname) 
		  
		  {
    SELECT ?y SAMPLE(?name)
    WHERE {
      ?x foaf:name ?name . 
    }
    ORDER BY ?x
    GROUP BY ?name
  }
		  
		  
	SELECT Str(?name2) Str(?pubname) Str(?date) ?pub
           WHERE{
             ?pub dc:creator ?autor2 .
             ?autor2 foaf:name ?name2 .
			 ?pub dcterms:issued ?date .
			 ?pub dc:title ?pubname . 
             {
               SELECT  ?pub
	       WHERE {
		    ?pub dc:creator ?autor . 
		    ?autor foaf:name ?name . 
		    FILTER regex(?name, 'James', 'i') .
		  }
		  ORDER BY ASC(?pub)
                  LIMIT 10
                }
              }GROUP BY ?pub
                  
  	  SELECT Str(?name2) Str(?pubname) Str(?date) ?pub
           WHERE{
             ?autor2 foaf:name ?name2 .
             ?pub dc:creator ?autor2 .
             ?pub dcterms:issued ?date .
	     ?pub dc:title ?pubname .
             {
              SELECT  DISTINCT ?pub 
	      WHERE {
		?pub dc:creator ?autor . 
		?autor foaf:name ?name .
                FILTER regex(?name, 'James', 'i') .
	      }ORDER BY ?pub
	       OFFSET 0 
	       LIMIT  10 
            }
          }ORDER BY ?pub ?autor2

		  
  
  */