package com.britesnow.snow.web.rest;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.inject.Singleton;
import com.britesnow.snow.util.Pair;
import com.britesnow.snow.web.RequestContext;
import com.britesnow.snow.web.HttpMethod;
import com.britesnow.snow.web.handler.ParamDef;
/**
* Note: the registerWeb*** must be called only in init time, as the Map are not concurrent
* for performance reasons.
*
* Internal only.
*
* @author jeremychone
* @since 2.0.0
*
*/
@Singleton
public class RestRegistry {
private Map<String,WebRestRef> webGetRefByPath = new HashMap<String, WebRestRef>();
private Map<String,WebRestRef> webPostRefByPath = new HashMap<String, WebRestRef>();
private Map<String,WebRestRef> webPutRefByPath = new HashMap<String, WebRestRef>();
private Map<String,WebRestRef> webDeleteRefByPath = new HashMap<String, WebRestRef>();
private Map<Pattern,WebRestRef> webGetRefByVaredPath = new HashMap<Pattern, WebRestRef>();
private Map<Pattern,WebRestRef> webPostRefByVaredPath = new HashMap<Pattern, WebRestRef>();
private Map<Pattern,WebRestRef> webPutRefByVaredPath = new HashMap<Pattern, WebRestRef>();
private Map<Pattern,WebRestRef> webDeleteRefByVaredPath = new HashMap<Pattern, WebRestRef>();
// --------- WebRef Getters --------- //
public WebRestRef getWebRestRef(RequestContext rc){
return getWebRestRef(rc,null);
}
public WebRestRef getWebRestRef(RequestContext rc,String resourcePath){
if (resourcePath == null){
resourcePath = rc.getResourcePath();
}
HttpMethod method = rc.getMethod();
WebRestRef ref = null;
// first, check if there is a perfect match.
Map<String,WebRestRef> refByPath = getRefByPath(method);
if (refByPath != null){
ref = refByPath.get(resourcePath);
}
// if still null, check if there is a vared path matching
if (ref == null){
Map<Pattern,WebRestRef> refByPattern = getRefByPattern(method);
if(refByPattern != null){
for (Pattern pattern : refByPattern.keySet()){
Matcher matcher = pattern.matcher(resourcePath);
if (matcher.matches()){
ref = refByPattern.get(pattern);
break;
}
}
}
}
return ref;
}
// --------- /WebRef Getters --------- //
// --------- Register Methods (called in init only) --------- //
public void registerWebRest(Class webClass, Method m, ParamDef[] paramDefs, HttpMethod method, String[] paths ){
Map<String,WebRestRef> refByPath = getRefByPath(method);
Map<Pattern,WebRestRef> refByPattern = getRefByPattern(method);
if (refByPath != null){
WebRestRef ref = new WebRestRef(webClass,m, paramDefs);
// if now paths, in the .value() then take the methodName as the path
if (paths.length == 0){
refByPath.put("/" + ref.getHandlerMethod().getName(), ref);
}else{
for (String path : paths){
if (path.indexOf("{") > -1){
Pair<Pattern, Map<Integer, String>> patternAndMap = getPathPatternAndMap(path);
Pattern pattern = patternAndMap.getFirst();
WebRestRef varPathRef = new WebRestRef(webClass,m, paramDefs,pattern,patternAndMap.getSecond());
refByPattern.put(pattern,varPathRef);
}else{
refByPath.put(path, ref);
}
}
}
}
}
// --------- /Register Methods (called in init only) --------- //
private Pair<Pattern,Map<Integer,String>> getPathPatternAndMap(String path){
// --- find the var names --- //
final String RGX_FIND_VAR = "\\{(.*?)\\}";
Pattern varFinderPattern = Pattern.compile(RGX_FIND_VAR);
Matcher varFinderMatcher = varFinderPattern.matcher(path);
Map<Integer,String> paramNameByIdx = new HashMap<Integer, String>();
int group_idx = 0;
StringBuilder pathRegExSb = new StringBuilder("^");
String str = path;
int str_idx = 0;
while (varFinderMatcher.find()) {
String paramName = varFinderMatcher.group();
paramName = paramName.substring(1,paramName.length() -1);
paramNameByIdx.put(group_idx, paramName);
pathRegExSb.append(regexEscape(str.substring(str_idx, varFinderMatcher.start())));
pathRegExSb.append("(.*?)");
str_idx = varFinderMatcher.end();
group_idx++;
}
pathRegExSb.append(regexEscape(str.substring(str_idx)));
pathRegExSb.append("$");
String pathRegEx = pathRegExSb.toString();
Pattern pathPattern = Pattern.compile(pathRegEx);
return new Pair<Pattern,Map<Integer,String>>(pathPattern,paramNameByIdx);
}
static private String regexEscape(String str){
return str.replace(".", "\\.");
}
private Map<Pattern,WebRestRef> getRefByPattern(HttpMethod httpMethod){
switch (httpMethod){
case GET:
return webGetRefByVaredPath;
case POST:
return webPostRefByVaredPath;
case PUT:
return webPutRefByVaredPath;
case DELETE:
return webDeleteRefByVaredPath;
default:
return null;
}
}
private Map<String,WebRestRef> getRefByPath(HttpMethod httpMethod){
switch (httpMethod){
case GET:
return webGetRefByPath;
case POST:
return webPostRefByPath;
case PUT:
return webPutRefByPath;
case DELETE:
return webDeleteRefByPath;
default:
return null;
}
}
}