translator: added support for the Apertium translation service

Also added feedback to source & target language menus to indicate which
languages are supported by the selected translation method. For Apertium, the
source language menu shows all possible source languages, and the target menu
shows the possible target languages for the chosen source language.

src/www/translator/translator.js

@@ -15,6 +15,7 @@ function Translator() {
     this.server.get_grammarlist(bind(this.extend_methods,this))
     update_language_menu(this,"source")
     update_language_menu(this,"target")
+    if(apertium) this.add_apertium()
     this.redraw();
 }
 
@@ -23,7 +24,7 @@ function update_language_menu(t,id) {
     clear(dl);
     for(var i in languages) {
 	var l=languages[i]
-	dl.appendChild(wrap("dt",radiobutton(id,l.code,l.name,bind(t.change,t))))
+	dl.appendChild(dt(radiobutton(id,l.code,l.name,bind(t.change,t))))
     }
 }
 
@@ -40,19 +41,68 @@ Translator.prototype.redraw=function() {
 	update_radiobutton("target",o.to)
 	update_radiobutton("view",o.view || "segmentbysegment")
 	update_checkbox("cloud",o.cloud  || false)
-	if(o.method!="Manual") {
+	switch(o.method) {
+	case "Manual":
+	case "Apertium":
+	    t.update_language_menus()
+	    t.update_translations()
+	    break;
+	default: // GF
 	    function cont2(gr_info) {
 		t.grammar_info=gr_info
+		t.update_language_menus() // needs grammar_info
 		t.update_translations()
 	    }
 	    function cont1() { t.server.grammar_info(cont2)}
 	    t.server.switch_grammar(o.method,cont1)
 	}
-	else
-	    t.update_translations()
     }
 }
 
+Translator.prototype.update_language_menus=function() {
+    var t=this
+    var o=t.document.options
+    var method=o.method+(o.method=="Apertium"?"/"+o.from:"")
+    if(t.menus_for==method) return;
+    t.menus_for=method
+    function mark_menu(name,supported) {
+	var menu=document.forms.options[name]
+	for(var i=0;i<menu.length;i++)
+	    menu[i].parentNode.parentNode.className=
+	      (supported(menu[i].value)?"":"un")+"supported"
+    }
+    function mark_menus(ssupport,tsupport) {
+	mark_menu("source",ssupport)
+	mark_menu("target",tsupport)
+    }
+    switch(o.method) {
+    case "Manual":
+	function yes(code) { return true; }
+	mark_menus(yes,yes)
+	break;
+    case "Apertium":
+	function ssupport(code) {
+	    return apertium.isTranslatable(alangcode(code))
+	}
+	function tsupport(code) {
+	  return apertium.isTranslatablePair(alangcode(o.from),alangcode(code))
+	}
+	mark_menus(ssupport,tsupport)
+	break;
+    default: // GF
+	var supported=bind(t.gf_supported,t)
+	mark_menus(supported,supported)
+    }
+}
+
+Translator.prototype.gf_supported=function(langcode) {
+    var t=this;
+    var concname=t.grammar_info.name+langcode
+    var l=t.grammar_info.languages
+    for(var i in l) if(l[i].name==concname) return true
+    return false
+}
+
 Translator.prototype.update_translations=function() {
     var t=this
     var doc=t.document
@@ -61,32 +111,51 @@ Translator.prototype.update_translations=function() {
     var ds=t.drawing.segments
     var ts=t.drawing.targets
 
-    function supported(concname) {
-	var l=t.grammar_info.languages
-	for(var i in l) if(l[i].name==concname) return true
-	return false
-    }
-
-    function update_translation(i) {
+    function replace(i) {
 	var segment=ss[i]
-	function replace() {
-	    if(ds) {
-		var sd=t.draw_segment(segment,i)
-		var old=ds[i]
-		ds[i]=sd
-		replaceNode(sd,old)
-	    }
-	    else if(ts) {
-		clear(ts[i])
-		ts[i].appendChild(text(segment.target+" "))
-	    }
+	if(ds) {
+	    var sd=t.draw_segment(segment,i)
+	    var old=ds[i]
+	    ds[i]=sd
+	    replaceNode(sd,old)
 	}
+	else if(ts) {
+	    clear(ts[i])
+	    ts[i].appendChild(text(segment.target+" "))
+	}
+    }
+    function update_apertium_translation(i,afrom,ato) {
+	var segment=ss[i]
 	function upd3(txts) {
 	    segment.target=txts[0];
 	    segment.options={method:o.method,from:o.from,to:o.to} // no sharing!
 	    if(txts.length>1) segment.choices=txts
 	    else delete segment.choices
-	    replace()
+	    replace(i)
+	}
+	function upd1(res) {
+	    //console.log(translate_output)
+	    if(res.translation) upd3([res.translation])
+	    else upd3(["["+res.error.message+"]"])
+	}
+	function upd0(source) { apertium.translate(source,afrom,ato,upd1) }
+	if(apertium.isTranslatablePair(afrom,ato)) {
+	    if(segment.options.method!="Manual" 
+	       && !eq_options(segment.options,o))
+		upd0(segment.source)
+	}
+	else
+	    upd3(["[Apertium does not support "+show_translation(o)+"]"])
+    }
+
+    function update_gf_translation(i,gfrom,gto) {
+	var segment=ss[i]
+	function upd3(txts) {
+	    segment.target=txts[0];
+	    segment.options={method:o.method,from:o.from,to:o.to} // no sharing!
+	    if(txts.length>1) segment.choices=txts
+	    else delete segment.choices
+	    replace(i)
 	}
 	function upd2(ts) {
 	    function unlex(txt,cont) { gfshell('ps -unlextext "'+txt+'"',cont) }
@@ -103,8 +172,8 @@ Translator.prototype.update_translations=function() {
 	function upd0(source) {
 	    t.server.translate({from:gfrom,to:gto,input:source},upd1)
 	}
-	var fls=supported(gfrom)
-	var tls=supported(gto)
+	var fls=t.gf_supported(o.from)
+	var tls=t.gf_supported(o.to)
 	if(fls && tls) {
 	    if(segment.options.method!="Manual" 
 	       && !eq_options(segment.options,o))
@@ -121,21 +190,36 @@ Translator.prototype.update_translations=function() {
 	}
     }
 
-    if(doc.options.method!="Manual") {
+    switch(doc.options.method) {
+    case "Manual":
+	break;
+    case "Apertium":
+	var afrom=alangcode(o.from)
+	var ato=alangcode(o.to)
+	for(var i in ss) update_apertium_translation(i,afrom,ato)
+	break;
+    default: // GF
 	var gname=t.grammar_info.name
 	var gfrom=gname+o.from
 	var gto=gname+o.to
-	for(var i in ss) update_translation(i)
+	for(var i in ss) update_gf_translation(i,gfrom,gto)
     }
 }
 
+Translator.prototype.add_apertium=function() {
+    var dl=element("methods")
+    if(dl)
+	dl.appendChild(dt(radiobutton("method","Apertium","Apertium",
+				      bind(this.change,this))))
+}
+
 Translator.prototype.extend_methods=function(grammars) {
     this.grammars=grammars
     var dl=element("methods")
     if(dl) for(var i in grammars) {
-	dl.appendChild(wrap("dt",radiobutton("method",grammars[i],
-					     "GF: "+grammars[i],
-					     bind(this.change,this))))
+	dl.appendChild(dt(radiobutton("method",grammars[i],
+				      "GF: "+grammars[i],
+				      bind(this.change,this))))
     }
     update_radiobutton("method",this.document.options.method)
 }
@@ -444,9 +528,9 @@ type Segment = { source:String, target:String, options:Options }
 type DocOptions = Options & { view:View }
 type Options = {from: Lang, to: Lang, method:Method}
 type Lang = String // Eng, Swe, Ita, etc
-type Method = "Manual" | GrammarName
+type Method = "Manual" | "Apertium" | GFGrammarName
 type View = "segmentbysegment" | "paralleltexts"
-type GrammarName = String // e.g. "Foods.pgf"
+type GFGrammarName = String // e.g. "Foods.pgf"
 */
 
 function eq_options(o1,o2) {
@@ -522,9 +606,9 @@ Translator.prototype.draw_segment_given_target=function(s,target,i) {
 	var autoB=radiobutton("method","Auto","Auto",change,!manual)
 	var manualB=radiobutton("method","Manual","Manual",change,manual)
 	return wrap("form",
-		    [wrap("dt",autoB),
-		     wrap("dt",manualB),
-		     wrap("dt",draw_translation(o))])
+		    [dt(autoB),
+		     dt(manualB),
+		     dt(draw_translation(o))])
     }
 
     function draw_options(o) {
@@ -548,26 +632,35 @@ function new_segment(source) {
     return { source:source, target:"", options:{} } // leave options empty
 }
 
-function draw_translation(o) {
-    return text("("+concname(o.from||"?")+" → "+concname(o.to||"?")+")")
+function draw_translation(o) { return text(show_translation(o)) }
+
+function show_translation(o) {
+    return "("+concname(o.from||"?")+" → "+concname(o.to||"?")+")"
 }
 
 /* --- Auxiliary functions -------------------------------------------------- */
 
-function lang(code,name) { return { code:code, name:name} }
-function lang1(name) {
+function lang(code,name,code2) { return {code:code, name:name, code2:code2} }
+function lang1(namecode2) {
+    var nc=namecode2.split(":");
+    var name=nc[0]
     var ws=name.split("/");
-    return ws.length==1 ? lang(name.substr(0,3),name) : lang(ws[0],ws[1]);
+    var code2=nc.length>1 ? nc[1] : ""
+    return ws.length==1 ? lang(name.substr(0,3),name,code2)
+	                : lang(ws[0],ws[1],code2);
 }
-var languages =
-    map(lang1,"Amharic Arabic Bulgarian Catalan Danish Dutch English Finnish French German Hindi Ina/Interlingua Italian Jpn/Japanese Latin Norwegian Polish Ron/Romanian Russian Spanish Swedish Thai Turkish Urdu".split(" "));
+
+var languages = // [ISO-639-2 code "/"] language name ":" ISO 639-1 code
+    map(lang1,"Amharic:am Arabic:ar Bulgarian:bg Catalan:ca Danish:da Dutch:nl English:en Finnish:fi French:fr German:de Hindi:hi Ina/Interlingua:ia Italian:it Jpn/Japanese:ja Latin:la Norwegian:nb Polish:pl Ron/Romanian:ro Russian:ru Spanish:es Swedish:sv Thai:th Turkish:tr Urdu:ur".split(" "));
 
 var langname={};
-for(var i in languages)
+var langcode2={}
+for(var i in languages) {
     langname[languages[i].code]=languages[i].name
-
+    langcode2[languages[i].code]=languages[i].code2
+}
 function concname(code) { return langname[code] || code; }
-
+function alangcode(code) { return langcode2[code] || code; }
 
 function tr_local() {
     /*