/*
* Copyright 2012 Objectos, Fábrica de Software LTDA.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package br.com.objectos.way.ui;
import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.util.Map;
import java.util.Set;
import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;
import com.github.mustachejava.Mustache;
import com.google.common.base.Throwables;
import com.google.inject.Inject;
import com.google.inject.Provider;
import com.google.inject.Singleton;
import com.google.sitebricks.client.transport.Json;
import com.google.sitebricks.headless.Reply;
import com.google.sitebricks.headless.Request;
/**
* @author marcio.endo@objectos.com.br (Marcio Endo)
*/
@Singleton
class PagesGuice extends Pages {
private final Mustaches mustaches;
private final ObjectMapper objectMapper;
private final Provider<Request> requests;
private final Views views;
@Inject
public PagesGuice(Mustaches mustaches,
ObjectMapper objectMapper,
Provider<Request> requests,
Views views) {
this.mustaches = mustaches;
this.objectMapper = objectMapper;
this.requests = requests;
this.views = views;
}
@Override
public Reply<?> get(Class<?> templateClass, Context context) {
Response response = new Response(templateClass, context);
return Reply.with(response.html).as(Html.class);
}
@Override
public Reply<?> post(Class<?> templateClass, Context context) {
Response response = new Response(templateClass, context);
return Reply.with(response.context).as(Json.class).type(Mimes.APPLICATION_JSON_UTF8);
}
@Override
public Reply<?> reply(Class<?> templateClass, Context context) {
Request request = requests.get();
Method method = Method.parse(request);
switch (method) {
case GET:
return get(templateClass, context);
case POST:
return post(templateClass, context);
default:
throw new IllegalArgumentException("Only GET and POST methods are supported");
}
}
private class Response {
final String html;
final String json;
final Context context;
public Response(Class<?> templateClass, Context context) {
String html = render(templateClass, context);
Set<String> viewSet = Tags.extractTemplates(html);
views.populate(context, viewSet);
this.json = toJson(context);
this.html = Tags.appendContext(html, json);
this.context = context;
}
}
private String render(Class<?> templateClass, Context context) {
try {
Mustache mustache = mustaches.compile(templateClass);
StringWriter writer = new StringWriter();
Map<?, ?> scope = toMustacheScope(context);
Writer execute = mustache.execute(writer, scope);
execute.flush();
return writer.toString();
} catch (IOException e) {
throw Throwables.propagate(e);
}
}
private String toJson(Context context) {
try {
return objectMapper.writeValueAsString(context);
} catch (JsonGenerationException e) {
throw Throwables.propagate(e);
} catch (JsonMappingException e) {
throw Throwables.propagate(e);
} catch (IOException e) {
throw Throwables.propagate(e);
}
}
private Map<?, ?> toMustacheScope(Context context) {
try {
String json = toJson(context);
return objectMapper.readValue(json, Map.class);
} catch (JsonGenerationException e) {
throw Throwables.propagate(e);
} catch (JsonMappingException e) {
throw Throwables.propagate(e);
} catch (IOException e) {
throw Throwables.propagate(e);
}
}
}