/**
* This file is part of alf.io.
*
* alf.io is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* alf.io is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with alf.io. If not, see <http://www.gnu.org/licenses/>.
*/
package alfio.util;
import alfio.config.WebSecurityConfig;
import alfio.manager.UploadedResourceManager;
import alfio.model.Event;
import com.samskivert.mustache.Mustache;
import com.samskivert.mustache.Mustache.Compiler;
import com.samskivert.mustache.Mustache.Formatter;
import com.samskivert.mustache.Template;
import org.apache.commons.lang3.tuple.Pair;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.MessageSource;
import org.springframework.core.io.AbstractResource;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.core.io.ClassPathResource;
import org.springframework.security.web.csrf.CsrfToken;
import org.springframework.web.context.support.ServletContextResource;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.i18n.MustacheLocalizationMessageInterceptor;
import org.springframework.web.servlet.support.RequestContextUtils;
import org.springframework.web.servlet.view.mustache.jmustache.JMustacheTemplateLoader;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* For hiding the uglyness :)
* */
public class TemplateManager {
private final MessageSource messageSource;
public enum TemplateOutput {
TEXT, HTML
}
private final Map<TemplateOutput, Compiler> compilers;
private final UploadedResourceManager uploadedResourceManager;
@Autowired
public TemplateManager(JMustacheTemplateLoader templateLoader,
MessageSource messageSource,
UploadedResourceManager uploadedResourceManager) {
this.messageSource = messageSource;
this.uploadedResourceManager = uploadedResourceManager;
Formatter dateFormatter = (o) -> {
return (o instanceof ZonedDateTime) ? DateTimeFormatter.ISO_ZONED_DATE_TIME
.format((ZonedDateTime) o) : String.valueOf(o);
};
this.compilers = new EnumMap<>(TemplateOutput.class);
this.compilers.put(TemplateOutput.TEXT, Mustache.compiler()
.escapeHTML(false)
.standardsMode(false)
.defaultValue("")
.nullValue("")
.withFormatter(dateFormatter)
.withLoader(templateLoader));
this.compilers.put(TemplateOutput.HTML, Mustache.compiler()
.escapeHTML(true)
.standardsMode(false)
.defaultValue("")
.nullValue("")
.withFormatter(dateFormatter)
.withLoader(templateLoader));
}
public String renderTemplate(TemplateResource templateResource, Map<String, Object> model, Locale locale) {
return render(new ClassPathResource(templateResource.classPath()), model, locale, templateResource.getTemplateOutput());
}
public String renderTemplate(Event event, TemplateResource templateResource, Map<String, Object> model, Locale locale) {
return uploadedResourceManager.findCascading(event.getOrganizationId(), event.getId(), templateResource.getSavedName(locale))
.map(resource -> render(new ByteArrayResource(resource), model, locale, templateResource.getTemplateOutput()))
.orElseGet(() -> renderTemplate(templateResource, model, locale));
}
public String renderString(String template, Map<String, Object> model, Locale locale, TemplateOutput templateOutput) {
return render(new ByteArrayResource(template.getBytes(StandardCharsets.UTF_8)), model, locale, templateOutput);
}
//TODO: to be removed when only the rest api will be exposed
public String renderServletContextResource(String servletContextResource, Map<String, Object> model, HttpServletRequest request, TemplateOutput templateOutput) {
model.put("request", request);
model.put(WebSecurityConfig.CSRF_PARAM_NAME, request.getAttribute(CsrfToken.class.getName()));
return render(new ServletContextResource(request.getServletContext(), servletContextResource), model, RequestContextUtils.getLocale(request), templateOutput);
}
private String render(AbstractResource resource, Map<String, Object> model, Locale locale, TemplateOutput templateOutput) {
try {
ModelAndView mv = new ModelAndView((String) null, model);
mv.addObject("format-date", MustacheCustomTagInterceptor.FORMAT_DATE);
mv.addObject(MustacheLocalizationMessageInterceptor.DEFAULT_MODEL_KEY, new CustomLocalizationMessageInterceptor(locale, messageSource).createTranslator());
return compile(resource, templateOutput).execute(mv.getModel());
} catch (Exception e) {
throw new IllegalStateException(e);
}
}
private Template compile(AbstractResource resource, TemplateOutput templateOutput) {
try (InputStreamReader tmpl = new InputStreamReader(resource.getInputStream(), StandardCharsets.UTF_8)) {
return compilers.get(templateOutput).compile(tmpl);
} catch (IOException ioe) {
throw new IllegalStateException(ioe);
}
}
private static final Pattern KEY_PATTERN = Pattern.compile("(.*?)[\\s\\[]");
private static final Pattern ARGS_PATTERN = Pattern.compile("\\[(.*?)\\]");
/**
* Split key from (optional) arguments.
*
* @param key
* @return localization key
*/
private static String extractKey(String key) {
Matcher matcher = KEY_PATTERN.matcher(key);
if (matcher.find()) {
return matcher.group(1);
}
return key;
}
/**
* Split args from input string.
* <p/>
* localization_key [param1] [param2] [param3]
*
* @param key
* @return List of extracted parameters
*/
private static List<String> extractParameters(String key) {
final Matcher matcher = ARGS_PATTERN.matcher(key);
final List<String> args = new ArrayList<>();
while (matcher.find()) {
args.add(matcher.group(1));
}
return args;
}
private static class CustomLocalizationMessageInterceptor {
private final Locale locale;
private final MessageSource messageSource;
private CustomLocalizationMessageInterceptor(Locale locale, MessageSource messageSource) {
this.locale = locale;
this.messageSource = messageSource;
}
protected Mustache.Lambda createTranslator() {
return (frag, out) -> {
String template = frag.execute();
final String key = extractKey(template);
final List<String> args = extractParameters(template);
final String text = messageSource.getMessage(key, args.toArray(), locale);
out.write(text);
};
}
}
private static final String START_TAG = "{{#i18n}}";
private static final String END_TAG = "{{/i18n}}";
private enum ParserState {
START {
@Override
public Pair<ParserState, Integer> next(String template, int idx, AST ast) {
int startTagIdx = template.indexOf(START_TAG, idx);
if (startTagIdx == -1) {
ast.addText(template);
return Pair.of(END, idx);
} else {
ast.addText(template.substring(0, startTagIdx));
ast.addI18NNode();
return Pair.of(OPEN_TAG, startTagIdx + START_TAG.length());
}
}
}, OPEN_TAG {
@Override
public Pair<ParserState, Integer> next(String template, int idx, AST ast) {
int startTagIdx = template.indexOf(START_TAG, idx);
int endTagIdx = template.indexOf(END_TAG, idx);
if (endTagIdx != -1 && startTagIdx != -1 && startTagIdx < endTagIdx) {
ast.addText(template.substring(idx, startTagIdx));
int startTagIdxBoundary = startTagIdx + START_TAG.length();
ast.addI18NNode();
return Pair.of(OPEN_TAG, startTagIdxBoundary);
} else if (endTagIdx == -1 && startTagIdx == -1) {
ast.addText(template.substring(idx));
return Pair.of(END, idx);
} else if (endTagIdx != -1) {
ast.addText(template.substring(idx, endTagIdx));
return Pair.of(CLOSE_TAG, endTagIdx);
} else {
throw new IllegalStateException("should not be reached");
}
}
}, CLOSE_TAG {
@Override
public Pair<ParserState, Integer> next(String template, int idx, AST ast) {
//
ast.focusToParent();
//
return Pair.of(OPEN_TAG, idx + END_TAG.length());
}
}, END {
@Override
public Pair<ParserState, Integer> next(String template, int idx, AST ast) {
if (ast.currentLevel != ast.root) {
throw new IllegalStateException("unbalanced tags");
}
return Pair.of(END, idx);
}
};
public abstract Pair<ParserState, Integer> next(String template, int idx, AST ast);
}
static class AST {
Node root = new Node();
Node currentLevel = root;
void addChild(Node node) {
node.parent = currentLevel;
currentLevel.addChild(node);
}
void addText(String text) {
if (text.length() > 0) {
addChild(new TextNode(text));
}
}
void addI18NNode() {
addChild(new I18NNode());
currentLevel = currentLevel.children.get(currentLevel.children.size() - 1);
}
void focusToParent() {
currentLevel = currentLevel.parent;
}
public void visit(StringBuilder sb, Locale locale, MessageSource messageSource) {
root.visit(sb, locale, messageSource);
}
}
static class Node {
Node parent;
List<Node> children = new ArrayList<>(1);
void addChild(Node node) {
children.add(node);
}
public void visit(StringBuilder sb, Locale locale, MessageSource messageSource) {
for (Node node : children) {
node.visit(sb, locale, messageSource);
}
}
}
static class TextNode extends Node {
String text;
TextNode(String text) {
this.text = text;
}
@Override
public void visit(StringBuilder sb, Locale locale, MessageSource messageSource) {
sb.append(text);
}
}
static class I18NNode extends Node {
@Override
public void visit(StringBuilder sb, Locale locale, MessageSource messageSource) {
StringBuilder internal = new StringBuilder();
for (Node node : children) {
node.visit(internal, locale, messageSource);
}
String childTemplate = internal.toString();
String key = extractKey(childTemplate);
List<String> args = extractParameters(childTemplate);
String text = messageSource.getMessage(key, args.toArray(), locale);
sb.append(text);
}
}
public static String translate(String template, Locale locale, MessageSource messageSource) {
StringBuilder sb = new StringBuilder(template.length());
AST ast = new AST();
ParserState state = ParserState.START;
int idx = 0;
while (true) {
Pair<ParserState, Integer> stateAndIdx = state.next(template, idx, ast);
state = stateAndIdx.getKey();
idx = stateAndIdx.getValue();
if (state == ParserState.END) {
break;
}
}
ast.visit(sb, locale, messageSource);
return sb.toString();
}
}