/**
* Resolves a module id to a package resource. If module id consists of just one term and resolves
* to a package directory, the main module of the package is returned. If the module id consists
* of several terms and the first term resolves to a package directory, the remaining part of the
* module id is resolved against the "lib" directory of the package.
*
* @link http://nodejs.org/docs/v0.4.4/api/modules.html#folders_as_Modules
* @param moduleName the name of the package to load
* @param localPath the path of the resource issuing this call
* @return the location of the package's main module
* @throws IOException an unrecoverable I/O exception occurred while reading the package
*/
protected Resource loadPackage(String moduleName, Repository localPath) throws IOException {
int slash = 0;
String packageName, remainingName;
do {
slash = moduleName.indexOf('/', slash + 1);
if (slash == -1) {
packageName = moduleName;
remainingName = null;
} else {
packageName = moduleName.substring(0, slash);
if (".".equals(packageName) || "..".equals(packageName)) continue;
remainingName = moduleName.substring(slash + 1);
}
Resource json = findResource(packageName + "/package.json", null, localPath);
if (json != null && json.exists()) {
Scriptable obj = parseJsonResource(json);
Repository parent = json.getParentRepository();
String moduleId;
Resource res;
if (remainingName == null) {
// get the main module of this package
moduleId = getStringProperty(obj, "main", null);
if (moduleId != null) {
// optimize for the common case where main module
// property links to the exact file name
res = parent.getResource(moduleId);
if (res != null && res.exists()) return res;
}
} else {
// map remaining name to libs directory
String lib = "lib";
Object dirs = ScriptableObject.getProperty(obj, "directories");
if (dirs instanceof Scriptable) {
lib = getStringProperty((Scriptable) dirs, "lib", "lib");
}
moduleId = lib + "/" + remainingName;
}
if (moduleId != null) {
for (ModuleLoader loader : loaders) {
res = parent.getResource(moduleId + loader.getExtension());
if (res != null && res.exists()) return res;
}
if (remainingName != null) {
res = parent.getResource(moduleId);
if (res != null && res.exists()) return res;
}
}
}
} while (slash != -1);
return findResource(moduleName + "/index", loaders, localPath);
}
/**
* Search for a repository in the local path, or the main repository path.
*
* @param path the repository name
* @param localPath a repository to look first
* @return the repository
* @throws IOException if an I/O error occurred
*/
public Repository findRepository(String path, Repository localPath) throws IOException {
// To be consistent, always return absolute repository if path is absolute
// if we make this dependent on whether files exist we introduce a lot of
// vague and undetermined behaviour.
File file = new File(path);
if (file.isAbsolute()) {
return new FileRepository(file);
}
if (localPath != null) {
Repository repository = localPath.getChildRepository(path);
if (repository != null && repository.exists()) {
return repository;
}
}
return config.getRepository(normalizePath(path));
}
/**
* Search for a resource in a local path, or the main repository path.
*
* @param path the resource name
* @param loaders optional list of module loaders
* @param localRoot a repository to look first
* @return the resource
* @throws IOException if an I/O error occurred
*/
public Resource findResource(String path, ModuleLoader[] loaders, Repository localRoot)
throws IOException {
// Note: as an extension to the CommonJS modules API
// we allow absolute module paths for resources
File file = new File(path);
if (file.isAbsolute()) {
Resource res;
outer:
if (loaders != null) {
// loaders must contain at least one loader
assert loaders.length > 0 && loaders[0] != null;
for (ModuleLoader loader : loaders) {
res = new FileResource(path + loader.getExtension());
if (res.exists()) {
break outer;
}
}
res = new FileResource(path + loaders[0].getExtension());
} else {
res = new FileResource(file);
}
res.setAbsolute(true);
return res;
} else if (localRoot != null && (path.startsWith("./") || path.startsWith("../"))) {
String newpath = localRoot.getRelativePath() + path;
return findResource(newpath, loaders, null);
} else {
return config.getResource(normalizePath(path), loaders);
}
}
/**
* Return a shell scope for interactive evaluation
*
* @return a shell scope
* @throws IOException an I/O related exception occurred
*/
public Scriptable getShellScope(RingoWorker worker) throws IOException {
Repository repository = new FileRepository("");
repository.setAbsolute(true);
Scriptable protoScope = mainScope != null ? mainScope : globalScope;
return new ModuleScope("<shell>", repository, protoScope, worker);
}