// ==========================================================================

// This software is subject to the provisions of the Zope Public License,

// Version 2.0 (ZPL). A copy of the ZPL should accompany this distribution.

// THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED

// WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

// WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS

// FOR A PARTICULAR PURPOSE.

// ==========================================================================

using System;

using System.Runtime.InteropServices;

using System.Collections.Specialized;

using System.Collections;

using System.Reflection;

namespace Python.Runtime {

// TODO: decide whether to support __all__ and / or whether to impl

// a 'preload' method to force names to be pre-loaded.

//========================================================================

// Implements a Python type that provides access to CLR namespaces. The

// type behaves like a Python module, and can contain other sub-modules.

//========================================================================

internal class ModuleObject : ExtensionType {

internal string moduleName;

string _namespace;

Hashtable cache;

static bool hacked;

IntPtr dict;

public ModuleObject(string name) : base() {

moduleName = (name == String.Empty) ? "CLR" : name;

cache = new Hashtable();

_namespace = name;

dict = Runtime.PyDict_New();

IntPtr pyname = Runtime.PyString_FromString(moduleName);

Runtime.PyDict_SetItemString(dict, "__name__", pyname);

Runtime.PyDict_SetItemString(dict, "__file__", Runtime.PyNone);

Runtime.PyDict_SetItemString(dict, "__doc__", Runtime.PyNone);

Runtime.Decref(pyname);

Marshal.WriteIntPtr(this.pyHandle, ObjectOffset.ob_dict, dict);

// This hackery is required in order to allow a plain Python to

// import the managed runtime via the CLR bootstrapper module.

// The standard Python machinery in control at the time of the

// import requires the module to pass PyModule_Check. :(

if (!hacked) {

IntPtr type = this.tpHandle;

IntPtr mro = Marshal.ReadIntPtr(type, TypeOffset.tp_mro);

IntPtr ext = Runtime.ExtendTuple(mro, Runtime.PyModuleType);

Marshal.WriteIntPtr(type, TypeOffset.tp_mro, ext);

Runtime.Decref(mro);

hacked = true;

}

}

public string ModuleName {

get {

return moduleName;

}

}

//===================================================================

// Returns a ClassBase object representing a type that appears in

// this module's namespace or a ModuleObject representing a child

// namespace (or null if the name is not found). This method does

// not increment the Python refcount of the returned object.

//===================================================================

public ManagedType GetAttribute(string name) {

Object ob = this.cache[name];

if (ob != null) {

return (ManagedType) ob;

}

string qname = (_namespace == String.Empty) ? name :

_namespace + "." + name;

ModuleObject m;

ClassBase c;

// If the fully-qualified name of the requested attribute is

// a namespace exported by a currently loaded assembly, return

// a new ModuleObject representing that namespace.

if (AssemblyManager.IsValidNamespace(qname)) {

m = new ModuleObject(qname);

StoreAttribute(name, m);

return (ManagedType) m;

}

// Look for a type in the current namespace. Note that this

// includes types, delegates, enums, interfaces and structs.

// Only public namespace members are exposed to Python.

Type type = AssemblyManager.LookupType(qname);

if (type != null) {

if (!type.IsPublic) {

return null;

}

c = ClassManager.GetClass(type);

StoreAttribute(name, c);

return (ManagedType) c;

}

// This is a little repetitive, but it ensures that the right

// thing happens with implicit assembly loading at a reasonable

// cost. Ask the AssemblyManager to do implicit loading for each

// of the steps in the qualified name, then try it again.

if (AssemblyManager.LoadImplicit(qname)) {

if (AssemblyManager.IsValidNamespace(qname)) {

m = new ModuleObject(qname);

StoreAttribute(name, m);

return (ManagedType) m;

}

type = AssemblyManager.LookupType(qname);

if (type != null) {

if (!type.IsPublic) {

return null;

}

c = ClassManager.GetClass(type);

StoreAttribute(name, c);

return (ManagedType) c;

}

}

return null;

}

//===================================================================

// Stores an attribute in the instance dict for future lookups.

//===================================================================

private void StoreAttribute(string name, ManagedType ob) {

Runtime.PyDict_SetItemString(dict, name, ob.pyHandle);

cache[name] = ob;

}

//===================================================================

// Preloads all currently-known names for the module namespace. This

// can be called multiple times, to add names from assemblies that

// may have been loaded since the last call to the method.

//===================================================================

public void LoadNames() {

foreach (string name in AssemblyManager.GetNames(_namespace)) {

if (!this.cache.ContainsKey(name)) {

ManagedType attr = this.GetAttribute(name);

if (Runtime.wrap_exceptions) {

if (attr is ClassBase) {

ClassBase c = attr as ClassBase;

if (c.is_exception) {

IntPtr p = attr.pyHandle;

IntPtr r = Exceptions.GetExceptionClassWrapper(p);

Runtime.PyDict_SetItemString(dict, name, r);

Runtime.Incref(r);

}

}

}

}

}

}

//====================================================================

// ModuleObject __getattribute__ implementation. Module attributes

// are always either classes or sub-modules representing subordinate

// namespaces. CLR modules implement a lazy pattern - the sub-modules

// and classes are created when accessed and cached for future use.

//====================================================================

[CallConvCdecl()]

public static IntPtr tp_getattro(IntPtr ob, IntPtr key) {

ModuleObject self = (ModuleObject)GetManagedObject(ob);

if (!Runtime.PyString_Check(key)) {

Exceptions.SetError(Exceptions.TypeError, "string expected");

return IntPtr.Zero;

}

IntPtr op = Runtime.PyDict_GetItem(self.dict, key);

if (op != IntPtr.Zero) {

Runtime.Incref(op);

return op;

}

string name = Runtime.GetManagedString(key);

if (name == "__dict__") {

Runtime.Incref(self.dict);

return self.dict;

}

ManagedType attr = self.GetAttribute(name);

if (attr == null) {

Exceptions.SetError(Exceptions.AttributeError, name);

return IntPtr.Zero;

}

// XXX - hack required to recognize exception types. These types

// may need to be wrapped in old-style class wrappers in versions

// of Python where new-style classes cannot be used as exceptions.

if (Runtime.wrap_exceptions) {

if (attr is ClassBase) {

ClassBase c = attr as ClassBase;

if (c.is_exception) {

IntPtr p = attr.pyHandle;

IntPtr r = Exceptions.GetExceptionClassWrapper(p);

Runtime.PyDict_SetItemString(self.dict, name, r);

Runtime.Incref(r);

return r;

}

}

}

Runtime.Incref(attr.pyHandle);

return attr.pyHandle;

}

//====================================================================

// ModuleObject __repr__ implementation.

//====================================================================

[CallConvCdecl()]

public static IntPtr tp_repr(IntPtr ob) {

ModuleObject self = (ModuleObject)GetManagedObject(ob);

string s = String.Format("<module '{0}'>", self.moduleName);

return Runtime.PyString_FromString(s);

}

}

}