static BindingFlags tbFlags;

static Dictionary<Type, IntPtr> cache;

static int obSize;

static TypeManager() {

tbFlags = BindingFlags.Public | BindingFlags.Static;

obSize = 5 * IntPtr.Size;

cache = new Dictionary<Type, IntPtr>(128);

}

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

// Given a managed Type derived from ExtensionType, get the handle to

// a Python type object that delegates its implementation to the Type

// object. These Python type instances are used to implement internal

// descriptor and utility types like ModuleObject, PropertyObject, etc.

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

internal static IntPtr GetTypeHandle(Type type) {

// Note that these types are cached with a refcount of 1, so they

// effectively exist until the CPython runtime is finalized.

IntPtr handle = IntPtr.Zero;

cache.TryGetValue(type, out handle);

if (handle != IntPtr.Zero) {

return handle;

}

handle = CreateType(type);

cache[type] = handle;

return handle;

}

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

// Get the handle of a Python type that reflects the given CLR type.

// The given ManagedType instance is a managed object that implements

// the appropriate semantics in Python for the reflected managed type.

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

internal static IntPtr GetTypeHandle(ManagedType obj, Type type) {

IntPtr handle = IntPtr.Zero;

cache.TryGetValue(type, out handle);

if (handle != IntPtr.Zero) {

return handle;

}

handle = CreateType(obj, type);

cache[type] = handle;

return handle;

}

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

// The following CreateType implementations do the necessary work to

// create Python types to represent managed extension types, reflected

// types, subclasses of reflected types and the managed metatype. The

// dance is slightly different for each kind of type due to different

// behavior needed and the desire to have the existing Python runtime

// do as much of the allocation and initialization work as possible.

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

internal static IntPtr CreateType(Type impl) {

IntPtr type = AllocateTypeObject(impl.Name);

// Set tp_basicsize to the size of our managed instance objects.

Marshal.WriteIntPtr(type, TypeOffset.tp_basicsize, (IntPtr)obSize);

IntPtr offset = (IntPtr)ObjectOffset.ob_dict;

Marshal.WriteIntPtr(type, TypeOffset.tp_dictoffset, offset);

InitializeSlots(type, impl);

int flags = TypeFlags.Default | TypeFlags.Managed |

TypeFlags.HeapType | TypeFlags.HaveGC;

Marshal.WriteIntPtr(type, TypeOffset.tp_flags, (IntPtr)flags);

Runtime.PyType_Ready(type);

IntPtr dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

IntPtr mod = Runtime.PyString_FromString("CLR");

Runtime.PyDict_SetItemString(dict, "__module__", mod);

InitMethods(type, impl);

return type;

}

internal static IntPtr CreateType(ManagedType impl, Type clrType) {

// Cleanup the type name to get rid of funny nested type names.

string name = "CLR." + clrType.FullName;

int i = name.LastIndexOf('+');

if (i > -1) {

name = name.Substring(i + 1);

}

i = name.LastIndexOf('.');

if (i > -1) {

name = name.Substring(i + 1);

}

IntPtr base_ = IntPtr.Zero;

// XXX Hack, use a different base class for System.Exception

// Python 2.5+ allows new style class exceptions but they *must*

// subclass BaseException (or better Exception).

#if (PYTHON25 || PYTHON26 || PYTHON27)

if (clrType == typeof(System.Exception)) {

base_ = Exceptions.Exception;

Runtime.Incref(base_);

} else

#endif

if (clrType.BaseType != null) {

ClassBase bc = ClassManager.GetClass(clrType.BaseType);

base_ = bc.pyHandle;

}

IntPtr type = AllocateTypeObject(name);

Marshal.WriteIntPtr(type,TypeOffset.ob_type,Runtime.PyCLRMetaType);

Runtime.Incref(Runtime.PyCLRMetaType);

Marshal.WriteIntPtr(type, TypeOffset.tp_basicsize, (IntPtr)obSize);

Marshal.WriteIntPtr(type, TypeOffset.tp_itemsize, IntPtr.Zero);

IntPtr offset = (IntPtr)ObjectOffset.ob_dict;

Marshal.WriteIntPtr(type, TypeOffset.tp_dictoffset, offset);

InitializeSlots(type, impl.GetType());

if (base_ != IntPtr.Zero) {

Marshal.WriteIntPtr(type, TypeOffset.tp_base, base_);

Runtime.Incref(base_);

}

int flags = TypeFlags.Default;

flags |= TypeFlags.Managed;

flags |= TypeFlags.HeapType;

flags |= TypeFlags.BaseType;

flags |= TypeFlags.HaveGC;

Marshal.WriteIntPtr(type, TypeOffset.tp_flags, (IntPtr)flags);

// Leverage followup initialization from the Python runtime. Note

// that the type of the new type must PyType_Type at the time we

// call this, else PyType_Ready will skip some slot initialization.

Runtime.PyType_Ready(type);

IntPtr dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

string mn = clrType.Namespace != null ? clrType.Namespace : "";

IntPtr mod = Runtime.PyString_FromString(mn);

Runtime.PyDict_SetItemString(dict, "__module__", mod);

// Hide the gchandle of the implementation in a magic type slot.

GCHandle gc = GCHandle.Alloc(impl);

Marshal.WriteIntPtr(type, TypeOffset.magic(), (IntPtr)gc);

// Set the handle attributes on the implementing instance.

impl.tpHandle = Runtime.PyCLRMetaType;

impl.gcHandle = gc;

impl.pyHandle = type;

//DebugUtil.DumpType(type);

return type;

}

internal static IntPtr CreateSubType(IntPtr args) {

IntPtr py_name = Runtime.PyTuple_GetItem(args, 0);

IntPtr bases = Runtime.PyTuple_GetItem(args, 1);

IntPtr dict = Runtime.PyTuple_GetItem(args, 2);

IntPtr base_ = Runtime.PyTuple_GetItem(bases, 0);

string name = Runtime.GetManagedString(py_name);

IntPtr type = AllocateTypeObject(name);

Marshal.WriteIntPtr(type,TypeOffset.ob_type,Runtime.PyCLRMetaType);

Runtime.Incref(Runtime.PyCLRMetaType);

Marshal.WriteIntPtr(type, TypeOffset.tp_basicsize, (IntPtr)obSize);

Marshal.WriteIntPtr(type, TypeOffset.tp_itemsize, IntPtr.Zero);

IntPtr offset = (IntPtr)ObjectOffset.ob_dict;

Marshal.WriteIntPtr(type, TypeOffset.tp_dictoffset, offset);

IntPtr dc = Runtime.PyDict_Copy(dict);

Marshal.WriteIntPtr(type, TypeOffset.tp_dict, dc);

Marshal.WriteIntPtr(type, TypeOffset.tp_base, base_);

Runtime.Incref(base_);

int flags = TypeFlags.Default;

flags |= TypeFlags.Managed;

flags |= TypeFlags.HeapType;

flags |= TypeFlags.BaseType;

flags |= TypeFlags.Subclass;

flags |= TypeFlags.HaveGC;

Marshal.WriteIntPtr(type, TypeOffset.tp_flags, (IntPtr)flags);

CopySlot(base_, type, TypeOffset.tp_traverse);

CopySlot(base_, type, TypeOffset.tp_clear);

CopySlot(base_, type, TypeOffset.tp_is_gc);

Runtime.PyType_Ready(type);

IntPtr tp_dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

IntPtr mod = Runtime.PyString_FromString("CLR");

Runtime.PyDict_SetItemString(tp_dict, "__module__", mod);

// for now, move up hidden handle...

IntPtr gc = Marshal.ReadIntPtr(base_, TypeOffset.magic());

Marshal.WriteIntPtr(type, TypeOffset.magic(), gc);

return type;

}

internal static IntPtr CreateMetaType(Type impl) {

// The managed metatype is functionally little different than the

// standard Python metatype (PyType_Type). It overrides certain of

// the standard type slots, and has to subclass PyType_Type for

// certain functions in the C runtime to work correctly with it.

IntPtr type = AllocateTypeObject("CLR Metatype");

IntPtr py_type = Runtime.PyTypeType;

Marshal.WriteIntPtr(type, TypeOffset.tp_base, py_type);

Runtime.Incref(py_type);

// Copy gc and other type slots from the base Python metatype.

CopySlot(py_type, type, TypeOffset.tp_basicsize);

CopySlot(py_type, type, TypeOffset.tp_itemsize);

CopySlot(py_type, type, TypeOffset.tp_dictoffset);

CopySlot(py_type, type, TypeOffset.tp_weaklistoffset);

CopySlot(py_type, type, TypeOffset.tp_traverse);

CopySlot(py_type, type, TypeOffset.tp_clear);

CopySlot(py_type, type, TypeOffset.tp_is_gc);

// Override type slots with those of the managed implementation.

InitializeSlots(type, impl);

int flags = TypeFlags.Default;

flags |= TypeFlags.Managed;

flags |= TypeFlags.HeapType;

flags |= TypeFlags.HaveGC;

Marshal.WriteIntPtr(type, TypeOffset.tp_flags, (IntPtr)flags);

Runtime.PyType_Ready(type);

IntPtr dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

IntPtr mod = Runtime.PyString_FromString("CLR");

Runtime.PyDict_SetItemString(dict, "__module__", mod);

//DebugUtil.DumpType(type);

return type;

}

internal static IntPtr BasicSubType(string name, IntPtr base_,

Type impl) {

// Utility to create a subtype of a std Python type, but with

// a managed type able to override implementation

IntPtr type = AllocateTypeObject(name);

//Marshal.WriteIntPtr(type, TypeOffset.tp_basicsize, (IntPtr)obSize);

//Marshal.WriteIntPtr(type, TypeOffset.tp_itemsize, IntPtr.Zero);

//IntPtr offset = (IntPtr)ObjectOffset.ob_dict;

//Marshal.WriteIntPtr(type, TypeOffset.tp_dictoffset, offset);

//IntPtr dc = Runtime.PyDict_Copy(dict);

//Marshal.WriteIntPtr(type, TypeOffset.tp_dict, dc);

Marshal.WriteIntPtr(type, TypeOffset.tp_base, base_);

Runtime.Incref(base_);

int flags = TypeFlags.Default;

flags |= TypeFlags.Managed;

flags |= TypeFlags.HeapType;

flags |= TypeFlags.HaveGC;

Marshal.WriteIntPtr(type, TypeOffset.tp_flags, (IntPtr)flags);

CopySlot(base_, type, TypeOffset.tp_traverse);

CopySlot(base_, type, TypeOffset.tp_clear);

CopySlot(base_, type, TypeOffset.tp_is_gc);

InitializeSlots(type, impl);

Runtime.PyType_Ready(type);

IntPtr tp_dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

IntPtr mod = Runtime.PyString_FromString("CLR");

Runtime.PyDict_SetItemString(tp_dict, "__module__", mod);

return type;

}

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

// Utility method to allocate a type object & do basic initialization.

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

internal static IntPtr AllocateTypeObject(string name) {

IntPtr type = Runtime.PyType_GenericAlloc(Runtime.PyTypeType, 0);

// Cheat a little: we'll set tp_name to the internal char * of

// the Python version of the type name - otherwise we'd have to

// allocate the tp_name and would have no way to free it.

IntPtr temp = Runtime.PyString_FromString(name);

IntPtr raw = Runtime.PyString_AS_STRING(temp);

Marshal.WriteIntPtr(type, TypeOffset.tp_name, raw);

Marshal.WriteIntPtr(type, TypeOffset.name, temp);

long ptr = type.ToInt64(); // 64-bit safe

temp = new IntPtr(ptr + TypeOffset.nb_add);

Marshal.WriteIntPtr(type, TypeOffset.tp_as_number, temp);

temp = new IntPtr(ptr + TypeOffset.sq_length);

Marshal.WriteIntPtr(type, TypeOffset.tp_as_sequence, temp);

temp = new IntPtr(ptr + TypeOffset.mp_length);

Marshal.WriteIntPtr(type, TypeOffset.tp_as_mapping, temp);

temp = new IntPtr(ptr + TypeOffset.bf_getreadbuffer);

Marshal.WriteIntPtr(type, TypeOffset.tp_as_buffer, temp);

return type;

}

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

// Given a newly allocated Python type object and a managed Type that

// provides the implementation for the type, connect the type slots of

// the Python object to the managed methods of the implementing Type.

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

internal static void InitializeSlots(IntPtr type, Type impl) {

Hashtable seen = new Hashtable(8);

Type offsetType = typeof(TypeOffset);

while (impl != null) {

MethodInfo[] methods = impl.GetMethods(tbFlags);

for (int i = 0; i < methods.Length; i++) {

MethodInfo method = methods[i];

string name = method.Name;

if (! (name.StartsWith("tp_") ||

name.StartsWith("nb_") ||

name.StartsWith("sq_") ||

name.StartsWith("mp_") ||

name.StartsWith("bf_")

) ) {

continue;

}

if (seen[name] != null) {

continue;

}

FieldInfo fi = offsetType.GetField(name);

int offset = (int)fi.GetValue(offsetType);

IntPtr slot = Interop.GetThunk(method);

Marshal.WriteIntPtr(type, offset, slot);

seen[name] = 1;

}

impl = impl.BaseType;

}

}

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

// Given a newly allocated Python type object and a managed Type that

// implements it, initialize any methods defined by the Type that need

// to appear in the Python type __dict__ (based on custom attribute).

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

private static void InitMethods(IntPtr pytype, Type type) {

IntPtr dict = Marshal.ReadIntPtr(pytype, TypeOffset.tp_dict);

Type marker = typeof(PythonMethodAttribute);

BindingFlags flags = BindingFlags.Public | BindingFlags.Static;

while (type != null) {

MethodInfo[] methods = type.GetMethods(flags);

for (int i = 0; i < methods.Length; i++) {

MethodInfo method = methods[i];

object[] attrs = method.GetCustomAttributes(marker, false);

if (attrs.Length > 0) {

string method_name = method.Name;

MethodInfo[] mi = new MethodInfo[1];

mi[0] = method;

MethodObject m = new TypeMethod(method_name, mi);

Runtime.PyDict_SetItemString(dict, method_name,

m.pyHandle);

}

}

type = type.BaseType;

}

}

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

// Utility method to copy slots from a given type to another type.

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

internal static void CopySlot(IntPtr from, IntPtr to, int offset) {

IntPtr fp = Marshal.ReadIntPtr(from, offset);

Marshal.WriteIntPtr(to, offset, fp);

}