#! /usr/bin/env python
"""Generate C code from an ASDL description."""

import os, sys

import asdl

TABSIZE = 4
MAX_COL = 80

def get_c_type(name):
 """Return a string for the C name of the type.

 This function special cases the default types provided by asdl.
 """
 if name in asdl.builtin_types:
 return name
 else:
 return "%s_ty" % name

def reflow_lines(s, depth):
 """Reflow the line s indented depth tabs.

 Return a sequence of lines where no line extends beyond MAX_COL
 when properly indented. The first line is properly indented based
 exclusively on depth * TABSIZE. All following lines -- these are
 the reflowed lines generated by this function -- start at the same
 column as the first character beyond the opening { in the first
 line.
 """
 size = MAX_COL - depth * TABSIZE
 if len(s) < size:
 return [s]

 lines = []
 cur = s
 padding = ""
 while len(cur) > size:
 i = cur.rfind(' ', 0, size)
 # XXX this should be fixed for real
 if i == -1 and 'GeneratorExp' in cur:
 i = size + 3
 assert i != -1, "Impossible line %d to reflow: %r" % (size, s)
 lines.append(padding + cur[:i])
 if len(lines) == 1:
 # find new size based on brace
 j = cur.find('{', 0, i)
 if j >= 0:
 j += 2 # account for the brace and the space after it
 size -= j
 padding = " " * j
 else:
 j = cur.find('(', 0, i)
 if j >= 0:
 j += 1 # account for the paren (no space after it)
 size -= j
 padding = " " * j
 cur = cur[i+1:]
 else:
 lines.append(padding + cur)
 return lines

def is_simple(sum):
 """Return True if a sum is a simple.

 A sum is simple if its types have no fields, e.g.
 unaryop = Invert | Not | UAdd | USub
 """
 for t in sum.types:
 if t.fields:
 return False
 return True


class EmitVisitor(asdl.VisitorBase):
 """Visit that emits lines"""

 def __init__(self, file):
 self.file = file
 self.identifiers = set()
 super(EmitVisitor, self).__init__()

 def emit_identifier(self, name):
 name = str(name)
 if name in self.identifiers:
 return
 self.emit("_Py_IDENTIFIER(%s);" % name, 0)
 self.identifiers.add(name)

 def emit(self, s, depth, reflow=True):
 # XXX reflow long lines?
 if reflow:
 lines = reflow_lines(s, depth)
 else:
 lines = [s]
 for line in lines:
 if line:
 line = (" " * TABSIZE * depth) + line
 self.file.write(line + "\n")


class TypeDefVisitor(EmitVisitor):
 def visitModule(self, mod):
 for dfn in mod.dfns:
 self.visit(dfn)

 def visitType(self, type, depth=0):
 self.visit(type.value, type.name, depth)

 def visitSum(self, sum, name, depth):
 if is_simple(sum):
 self.simple_sum(sum, name, depth)
 else:
 self.sum_with_constructors(sum, name, depth)

 def simple_sum(self, sum, name, depth):
 enum = []
 for i in range(len(sum.types)):
 type = sum.types[i]
 enum.append("%s=%d" % (type.name, i + 1))
 enums = ", ".join(enum)
 ctype = get_c_type(name)
 s = "typedef enum _%s { %s } %s;" % (name, enums, ctype)
 self.emit(s, depth)
 self.emit("", depth)

 def sum_with_constructors(self, sum, name, depth):
 ctype = get_c_type(name)
 s = "typedef struct _%(name)s *%(ctype)s;" % locals()
 self.emit(s, depth)
 self.emit("", depth)

 def visitProduct(self, product, name, depth):
 ctype = get_c_type(name)
 s = "typedef struct _%(name)s *%(ctype)s;" % locals()
 self.emit(s, depth)
 self.emit("", depth)


class StructVisitor(EmitVisitor):
 """Visitor to generate typedefs for AST."""

 def visitModule(self, mod):
 for dfn in mod.dfns:
 self.visit(dfn)

 def visitType(self, type, depth=0):
 self.visit(type.value, type.name, depth)

 def visitSum(self, sum, name, depth):
 if not is_simple(sum):
 self.sum_with_constructors(sum, name, depth)

 def sum_with_constructors(self, sum, name, depth):
 def emit(s, depth=depth):
 self.emit(s % sys._getframe(1).f_locals, depth)
 enum = []
 for i in range(len(sum.types)):
 type = sum.types[i]
 enum.append("%s_kind=%d" % (type.name, i + 1))

 emit("enum _%(name)s_kind {" + ", ".join(enum) + "};")

 emit("struct _%(name)s {")
 emit("enum _%(name)s_kind kind;", depth + 1)
 emit("union {", depth + 1)
 for t in sum.types:
 self.visit(t, depth + 2)
 emit("} v;", depth + 1)
 for field in sum.attributes:
 # rudimentary attribute handling
 type = str(field.type)
 assert type in asdl.builtin_types, type
 emit("%s %s;" % (type, field.name), depth + 1);
 emit("};")
 emit("")

 def visitConstructor(self, cons, depth):
 if cons.fields:
 self.emit("struct {", depth)
 for f in cons.fields:
 self.visit(f, depth + 1)
 self.emit("} %s;" % cons.name, depth)
 self.emit("", depth)

 def visitField(self, field, depth):
 # XXX need to lookup field.type, because it might be something
 # like a builtin...
 ctype = get_c_type(field.type)
 name = field.name
 if field.seq:
 if field.type == 'cmpop':
 self.emit("asdl_int_seq *%(name)s;" % locals(), depth)
 else:
 self.emit("asdl_seq *%(name)s;" % locals(), depth)
 else:
 self.emit("%(ctype)s %(name)s;" % locals(), depth)

 def visitProduct(self, product, name, depth):
 self.emit("struct _%(name)s {" % locals(), depth)
 for f in product.fields:
 self.visit(f, depth + 1)
 for field in product.attributes:
 # rudimentary attribute handling
 type = str(field.type)
 assert type in asdl.builtin_types, type
 self.emit("%s %s;" % (type, field.name), depth + 1);
 self.emit("};", depth)
 self.emit("", depth)


class PrototypeVisitor(EmitVisitor):
 """Generate function prototypes for the .h file"""

 def visitModule(self, mod):
 for dfn in mod.dfns:
 self.visit(dfn)

 def visitType(self, type):
 self.visit(type.value, type.name)

 def visitSum(self, sum, name):
 if is_simple(sum):
 pass # XXX
 else:
 for t in sum.types:
 self.visit(t, name, sum.attributes)

 def get_args(self, fields):
 """Return list of C argument into, one for each field.

 Argument info is 3-tuple of a C type, variable name, and flag
 that is true if type can be NULL.
 """
 args = []
 unnamed = {}
 for f in fields:
 if f.name is None:
 name = f.type
 c = unnamed[name] = unnamed.get(name, 0) + 1
 if c > 1:
 name = "name%d" % (c - 1)
 else:
 name = f.name
 # XXX should extend get_c_type() to handle this
 if f.seq:
 if f.type == 'cmpop':
 ctype = "asdl_int_seq *"
 else:
 ctype = "asdl_seq *"
 else:
 ctype = get_c_type(f.type)
 args.append((ctype, name, f.opt or f.seq))
 return args

 def visitConstructor(self, cons, type, attrs):
 args = self.get_args(cons.fields)
 attrs = self.get_args(attrs)
 ctype = get_c_type(type)
 self.emit_function(cons.name, ctype, args, attrs)

 def emit_function(self, name, ctype, args, attrs, union=True):
 args = args + attrs
 if args:
 argstr = ", ".join(["%s %s" % (atype, aname)
 for atype, aname, opt in args])
 argstr += ", PyArena *arena"
 else:
 argstr = "PyArena *arena"
 margs = "a0"
 for i in range(1, len(args)+1):
 margs += ", a%d" % i
 self.emit("#define %s(%s) _Py_%s(%s)" % (name, margs, name, margs), 0,
 reflow=False)
 self.emit("%s _Py_%s(%s);" % (ctype, name, argstr), False)

 def visitProduct(self, prod, name):
 self.emit_function(name, get_c_type(name),
 self.get_args(prod.fields),
 self.get_args(prod.attributes),
 union=False)


class FunctionVisitor(PrototypeVisitor):
 """Visitor to generate constructor functions for AST."""

 def emit_function(self, name, ctype, args, attrs, union=True):
 def emit(s, depth=0, reflow=True):
 self.emit(s, depth, reflow)
 argstr = ", ".join(["%s %s" % (atype, aname)
 for atype, aname, opt in args + attrs])
 if argstr:
 argstr += ", PyArena *arena"
 else:
 argstr = "PyArena *arena"
 self.emit("%s" % ctype, 0)
 emit("%s(%s)" % (name, argstr))
 emit("{")
 emit("%s p;" % ctype, 1)
 for argtype, argname, opt in args:
 if not opt and argtype != "int":
 emit("if (!%s) {" % argname, 1)
 emit("PyErr_SetString(PyExc_ValueError,", 2)
 msg = "field %s is required for %s" % (argname, name)
 emit(' "%s");' % msg,
 2, reflow=False)
 emit('return NULL;', 2)
 emit('}', 1)

 emit("p = (%s)PyArena_Malloc(arena, sizeof(*p));" % ctype, 1);
 emit("if (!p)", 1)
 emit("return NULL;", 2)
 if union:
 self.emit_body_union(name, args, attrs)
 else:
 self.emit_body_struct(name, args, attrs)
 emit("return p;", 1)
 emit("}")
 emit("")

 def emit_body_union(self, name, args, attrs):
 def emit(s, depth=0, reflow=True):
 self.emit(s, depth, reflow)
 emit("p->kind = %s_kind;" % name, 1)
 for argtype, argname, opt in args:
 emit("p->v.%s.%s = %s;" % (name, argname, argname), 1)
 for argtype, argname, opt in attrs:
 emit("p->%s = %s;" % (argname, argname), 1)

 def emit_body_struct(self, name, args, attrs):
 def emit(s, depth=0, reflow=True):
 self.emit(s, depth, reflow)
 for argtype, argname, opt in args:
 emit("p->%s = %s;" % (argname, argname), 1)
 for argtype, argname, opt in attrs:
 emit("p->%s = %s;" % (argname, argname), 1)


class PickleVisitor(EmitVisitor):

 def visitModule(self, mod):
 for dfn in mod.dfns:
 self.visit(dfn)

 def visitType(self, type):
 self.visit(type.value, type.name)

 def visitSum(self, sum, name):
 pass

 def visitProduct(self, sum, name):
 pass

 def visitConstructor(self, cons, name):
 pass

 def visitField(self, sum):
 pass


class Obj2ModPrototypeVisitor(PickleVisitor):
 def visitProduct(self, prod, name):
 code = "static int obj2ast_%s(PyObject* obj, %s* out, PyArena* arena);"
 self.emit(code % (name, get_c_type(name)), 0)

 visitSum = visitProduct


class Obj2ModVisitor(PickleVisitor):
 def funcHeader(self, name):
 ctype = get_c_type(name)
 self.emit("int", 0)
 self.emit("obj2ast_%s(PyObject* obj, %s* out, PyArena* arena)" % (name, ctype), 0)
 self.emit("{", 0)
 self.emit("int isinstance;", 1)
 self.emit("", 0)

 def sumTrailer(self, name, add_label=False):
 self.emit("", 0)
 # there's really nothing more we can do if this fails ...
 error = "expected some sort of %s, but got %%R" % name
 format = "PyErr_Format(PyExc_TypeError, \"%s\", obj);"
 self.emit(format % error, 1, reflow=False)
 if add_label:
 self.emit("failed:", 1)
 self.emit("Py_XDECREF(tmp);", 1)
 self.emit("return 1;", 1)
 self.emit("}", 0)
 self.emit("", 0)

 def simpleSum(self, sum, name):
 self.funcHeader(name)
 for t in sum.types:
 line = ("isinstance = PyObject_IsInstance(obj, "
 "(PyObject *)%s_type);")
 self.emit(line % (t.name,), 1)
 self.emit("if (isinstance == -1) {", 1)
 self.emit("return 1;", 2)
 self.emit("}", 1)
 self.emit("if (isinstance) {", 1)
 self.emit("*out = %s;" % t.name, 2)
 self.emit("return 0;", 2)
 self.emit("}", 1)
 self.sumTrailer(name)

 def buildArgs(self, fields):
 return ", ".join(fields + ["arena"])

 def complexSum(self, sum, name):
 self.funcHeader(name)
 self.emit("PyObject *tmp = NULL;", 1)
 for a in sum.attributes:
 self.visitAttributeDeclaration(a, name, sum=sum)
 self.emit("", 0)
 # XXX: should we only do this for 'expr'?
 self.emit("if (obj == Py_None) {", 1)
 self.emit("*out = NULL;", 2)
 self.emit("return 0;", 2)
 self.emit("}", 1)
 for a in sum.attributes:
 self.visitField(a, name, sum=sum, depth=1)
 for t in sum.types:
 line = "isinstance = PyObject_IsInstance(obj, (PyObject*)%s_type);"
 self.emit(line % (t.name,), 1)
 self.emit("if (isinstance == -1) {", 1)
 self.emit("return 1;", 2)
 self.emit("}", 1)
 self.emit("if (isinstance) {", 1)
 for f in t.fields:
 self.visitFieldDeclaration(f, t.name, sum=sum, depth=2)
 self.emit("", 0)
 for f in t.fields:
 self.visitField(f, t.name, sum=sum, depth=2)
 args = [f.name for f in t.fields] + [a.name for a in sum.attributes]
 self.emit("*out = %s(%s);" % (t.name, self.buildArgs(args)), 2)
 self.emit("if (*out == NULL) goto failed;", 2)
 self.emit("return 0;", 2)
 self.emit("}", 1)
 self.sumTrailer(name, True)

 def visitAttributeDeclaration(self, a, name, sum=sum):
 ctype = get_c_type(a.type)
 self.emit("%s %s;" % (ctype, a.name), 1)

 def visitSum(self, sum, name):
 if is_simple(sum):
 self.simpleSum(sum, name)
 else:
 self.complexSum(sum, name)

 def visitProduct(self, prod, name):
 ctype = get_c_type(name)
 self.emit("int", 0)
 self.emit("obj2ast_%s(PyObject* obj, %s* out, PyArena* arena)" % (name, ctype), 0)
 self.emit("{", 0)
 self.emit("PyObject* tmp = NULL;", 1)
 for f in prod.fields:
 self.visitFieldDeclaration(f, name, prod=prod, depth=1)
 for a in prod.attributes:
 self.visitFieldDeclaration(a, name, prod=prod, depth=1)
 self.emit("", 0)
 for f in prod.fields:
 self.visitField(f, name, prod=prod, depth=1)
 for a in prod.attributes:
 self.visitField(a, name, prod=prod, depth=1)
 args = [f.name for f in prod.fields]
 args.extend([a.name for a in prod.attributes])
 self.emit("*out = %s(%s);" % (name, self.buildArgs(args)), 1)
 self.emit("return 0;", 1)
 self.emit("failed:", 0)
 self.emit("Py_XDECREF(tmp);", 1)
 self.emit("return 1;", 1)
 self.emit("}", 0)
 self.emit("", 0)

 def visitFieldDeclaration(self, field, name, sum=None, prod=None, depth=0):
 ctype = get_c_type(field.type)
 if field.seq:
 if self.isSimpleType(field):
 self.emit("asdl_int_seq* %s;" % field.name, depth)
 else:
 self.emit("asdl_seq* %s;" % field.name, depth)
 else:
 ctype = get_c_type(field.type)
 self.emit("%s %s;" % (ctype, field.name), depth)

 def isSimpleSum(self, field):
 # XXX can the members of this list be determined automatically?
 return field.type in ('expr_context', 'boolop', 'operator',
 'unaryop', 'cmpop')

 def isNumeric(self, field):
 return get_c_type(field.type) in ("int", "bool")

 def isSimpleType(self, field):
 return self.isSimpleSum(field) or self.isNumeric(field)

 def visitField(self, field, name, sum=None, prod=None, depth=0):
 ctype = get_c_type(field.type)
 self.emit("if (_PyObject_LookupAttrId(obj, &PyId_%s, &tmp) < 0) {" % field.name, depth)
 self.emit("return 1;", depth+1)
 self.emit("}", depth)
 if not field.opt:
 self.emit("if (tmp == NULL) {", depth)
 message = "required field \\\"%s\\\" missing from %s" % (field.name, name)
 format = "PyErr_SetString(PyExc_TypeError, \"%s\");"
 self.emit(format % message, depth+1, reflow=False)
 self.emit("return 1;", depth+1)
 else:
 self.emit("if (tmp == NULL || tmp == Py_None) {", depth)
 self.emit("Py_CLEAR(tmp);", depth+1)
 if self.isNumeric(field):
 self.emit("%s = 0;" % field.name, depth+1)
 elif not self.isSimpleType(field):
 self.emit("%s = NULL;" % field.name, depth+1)
 else:
 raise TypeError("could not determine the default value for %s" % field.name)
 self.emit("}", depth)
 self.emit("else {", depth)

 self.emit("int res;", depth+1)
 if field.seq:
 self.emit("Py_ssize_t len;", depth+1)
 self.emit("Py_ssize_t i;", depth+1)
 self.emit("if (!PyList_Check(tmp)) {", depth+1)
 self.emit("PyErr_Format(PyExc_TypeError, \"%s field \\\"%s\\\" must "
 "be a list, not a %%.200s\", tmp->ob_type->tp_name);" %
 (name, field.name),
 depth+2, reflow=False)
 self.emit("goto failed;", depth+2)
 self.emit("}", depth+1)
 self.emit("len = PyList_GET_SIZE(tmp);", depth+1)
 if self.isSimpleType(field):
 self.emit("%s = _Py_asdl_int_seq_new(len, arena);" % field.name, depth+1)
 else:
 self.emit("%s = _Py_asdl_seq_new(len, arena);" % field.name, depth+1)
 self.emit("if (%s == NULL) goto failed;" % field.name, depth+1)
 self.emit("for (i = 0; i < len; i++) {", depth+1)
 self.emit("%s val;" % ctype, depth+2)
 self.emit("res = obj2ast_%s(PyList_GET_ITEM(tmp, i), &val, arena);" %
 field.type, depth+2, reflow=False)
 self.emit("if (res != 0) goto failed;", depth+2)
 self.emit("if (len != PyList_GET_SIZE(tmp)) {", depth+2)
 self.emit("PyErr_SetString(PyExc_RuntimeError, \"%s field \\\"%s\\\" "
 "changed size during iteration\");" %
 (name, field.name),
 depth+3, reflow=False)
 self.emit("goto failed;", depth+3)
 self.emit("}", depth+2)
 self.emit("asdl_seq_SET(%s, i, val);" % field.name, depth+2)
 self.emit("}", depth+1)
 else:
 self.emit("res = obj2ast_%s(tmp, &%s, arena);" %
 (field.type, field.name), depth+1)
 self.emit("if (res != 0) goto failed;", depth+1)

 self.emit("Py_CLEAR(tmp);", depth+1)
 self.emit("}", depth)


class MarshalPrototypeVisitor(PickleVisitor):

 def prototype(self, sum, name):
 ctype = get_c_type(name)
 self.emit("static int marshal_write_%s(PyObject **, int *, %s);"
 % (name, ctype), 0)

 visitProduct = visitSum = prototype


class PyTypesDeclareVisitor(PickleVisitor):

 def visitProduct(self, prod, name):
 self.emit("static PyTypeObject *%s_type;" % name, 0)
 self.emit("static PyObject* ast2obj_%s(void*);" % name, 0)
 if prod.attributes:
 for a in prod.attributes:
 self.emit_identifier(a.name)
 self.emit("static char *%s_attributes[] = {" % name, 0)
 for a in prod.attributes:
 self.emit('"%s",' % a.name, 1)
 self.emit("};", 0)
 if prod.fields:
 for f in prod.fields:
 self.emit_identifier(f.name)
 self.emit("static char *%s_fields[]={" % name,0)
 for f in prod.fields:
 self.emit('"%s",' % f.name, 1)
 self.emit("};", 0)

 def visitSum(self, sum, name):
 self.emit("static PyTypeObject *%s_type;" % name, 0)
 if sum.attributes:
 for a in sum.attributes:
 self.emit_identifier(a.name)
 self.emit("static char *%s_attributes[] = {" % name, 0)
 for a in sum.attributes:
 self.emit('"%s",' % a.name, 1)
 self.emit("};", 0)
 ptype = "void*"
 if is_simple(sum):
 ptype = get_c_type(name)
 tnames = []
 for t in sum.types:
 tnames.append(str(t.name)+"_singleton")
 tnames = ", *".join(tnames)
 self.emit("static PyObject *%s;" % tnames, 0)
 self.emit("static PyObject* ast2obj_%s(%s);" % (name, ptype), 0)
 for t in sum.types:
 self.visitConstructor(t, name)

 def visitConstructor(self, cons, name):
 self.emit("static PyTypeObject *%s_type;" % cons.name, 0)
 if cons.fields:
 for t in cons.fields:
 self.emit_identifier(t.name)
 self.emit("static char *%s_fields[]={" % cons.name, 0)
 for t in cons.fields:
 self.emit('"%s",' % t.name, 1)
 self.emit("};",0)

class PyTypesVisitor(PickleVisitor):

 def visitModule(self, mod):
 self.emit("""
_Py_IDENTIFIER(_fields);
_Py_IDENTIFIER(_attributes);

typedef struct {
 PyObject_HEAD
 PyObject *dict;
} AST_object;

static void
ast_dealloc(AST_object *self)
{
 /* bpo-31095: UnTrack is needed before calling any callbacks */
 PyObject_GC_UnTrack(self);
 Py_CLEAR(self->dict);
 Py_TYPE(self)->tp_free(self);
}

static int
ast_traverse(AST_object *self, visitproc visit, void *arg)
{
 Py_VISIT(self->dict);
 return 0;
}

static int
ast_clear(AST_object *self)
{
 Py_CLEAR(self->dict);
 return 0;
}

static int
ast_type_init(PyObject *self, PyObject *args, PyObject *kw)
{
 Py_ssize_t i, numfields = 0;
 int res = -1;
 PyObject *key, *value, *fields;
 if (_PyObject_LookupAttrId((PyObject*)Py_TYPE(self), &PyId__fields, &fields) < 0) {
 goto cleanup;
 }
 if (fields) {
 numfields = PySequence_Size(fields);
 if (numfields == -1)
 goto cleanup;
 }

 res = 0; /* if no error occurs, this stays 0 to the end */
 if (numfields < PyTuple_GET_SIZE(args)) {
 PyErr_Format(PyExc_TypeError, "%.400s constructor takes at most "
 "%zd positional argument%s",
 Py_TYPE(self)->tp_name,
 numfields, numfields == 1 ? "" : "s");
 res = -1;
 goto cleanup;
 }
 for (i = 0; i < PyTuple_GET_SIZE(args); i++) {
 /* cannot be reached when fields is NULL */
 PyObject *name = PySequence_GetItem(fields, i);
 if (!name) {
 res = -1;
 goto cleanup;
 }
 res = PyObject_SetAttr(self, name, PyTuple_GET_ITEM(args, i));
 Py_DECREF(name);
 if (res < 0)
 goto cleanup;
 }
 if (kw) {
 i = 0; /* needed by PyDict_Next */
 while (PyDict_Next(kw, &i, &key, &value)) {
 res = PyObject_SetAttr(self, key, value);
 if (res < 0)
 goto cleanup;
 }
 }
 cleanup:
 Py_XDECREF(fields);
 return res;
}

/* Pickling support */
static PyObject *
ast_type_reduce(PyObject *self, PyObject *unused)
{
 _Py_IDENTIFIER(__dict__);
 PyObject *dict;
 if (_PyObject_LookupAttrId(self, &PyId___dict__, &dict) < 0) {
 return NULL;
 }
 if (dict) {
 return Py_BuildValue("O()N", Py_TYPE(self), dict);
 }
 return Py_BuildValue("O()", Py_TYPE(self));
}

static PyMethodDef ast_type_methods[] = {
 {"__reduce__", ast_type_reduce, METH_NOARGS, NULL},
 {NULL}
};

static PyGetSetDef ast_type_getsets[] = {
 {"__dict__", PyObject_GenericGetDict, PyObject_GenericSetDict},
 {NULL}
};

static PyTypeObject AST_type = {
 PyVarObject_HEAD_INIT(&PyType_Type, 0)
 "_ast.AST",
 sizeof(AST_object),
 0,
 (destructor)ast_dealloc, /* tp_dealloc */
 0, /* tp_vectorcall_offset */
 0, /* tp_getattr */
 0, /* tp_setattr */
 0, /* tp_as_async */
 0, /* tp_repr */
 0, /* tp_as_number */
 0, /* tp_as_sequence */
 0, /* tp_as_mapping */
 0, /* tp_hash */
 0, /* tp_call */
 0, /* tp_str */
 PyObject_GenericGetAttr, /* tp_getattro */
 PyObject_GenericSetAttr, /* tp_setattro */
 0, /* tp_as_buffer */
 Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /* tp_flags */
 0, /* tp_doc */
 (traverseproc)ast_traverse, /* tp_traverse */
 (inquiry)ast_clear, /* tp_clear */
 0, /* tp_richcompare */
 0, /* tp_weaklistoffset */
 0, /* tp_iter */
 0, /* tp_iternext */
 ast_type_methods, /* tp_methods */
 0, /* tp_members */
 ast_type_getsets, /* tp_getset */
 0, /* tp_base */
 0, /* tp_dict */
 0, /* tp_descr_get */
 0, /* tp_descr_set */
 offsetof(AST_object, dict),/* tp_dictoffset */
 (initproc)ast_type_init, /* tp_init */
 PyType_GenericAlloc, /* tp_alloc */
 PyType_GenericNew, /* tp_new */
 PyObject_GC_Del, /* tp_free */
};


static PyTypeObject* make_type(char *type, PyTypeObject* base, char**fields, int num_fields)
{
 _Py_IDENTIFIER(__module__);
 _Py_IDENTIFIER(_ast);
 PyObject *fnames, *result;
 int i;
 fnames = PyTuple_New(num_fields);
 if (!fnames) return NULL;
 for (i = 0; i < num_fields; i++) {
 PyObject *field = PyUnicode_FromString(fields[i]);
 if (!field) {
 Py_DECREF(fnames);
 return NULL;
 }
 PyTuple_SET_ITEM(fnames, i, field);
 }
 result = PyObject_CallFunction((PyObject*)&PyType_Type, "s(O){OOOO}",
 type, base,
 _PyUnicode_FromId(&PyId__fields), fnames,
 _PyUnicode_FromId(&PyId___module__),
 _PyUnicode_FromId(&PyId__ast));
 Py_DECREF(fnames);
 return (PyTypeObject*)result;
}

static int add_attributes(PyTypeObject* type, char**attrs, int num_fields)
{
 int i, result;
 PyObject *s, *l = PyTuple_New(num_fields);
 if (!l)
 return 0;
 for (i = 0; i < num_fields; i++) {
 s = PyUnicode_FromString(attrs[i]);
 if (!s) {
 Py_DECREF(l);
 return 0;
 }
 PyTuple_SET_ITEM(l, i, s);
 }
 result = _PyObject_SetAttrId((PyObject*)type, &PyId__attributes, l) >= 0;
 Py_DECREF(l);
 return result;
}

/* Conversion AST -> Python */

static PyObject* ast2obj_list(asdl_seq *seq, PyObject* (*func)(void*))
{
 Py_ssize_t i, n = asdl_seq_LEN(seq);
 PyObject *result = PyList_New(n);
 PyObject *value;
 if (!result)
 return NULL;
 for (i = 0; i < n; i++) {
 value = func(asdl_seq_GET(seq, i));
 if (!value) {
 Py_DECREF(result);
 return NULL;
 }
 PyList_SET_ITEM(result, i, value);
 }
 return result;
}

static PyObject* ast2obj_object(void *o)
{
 if (!o)
 o = Py_None;
 Py_INCREF((PyObject*)o);
 return (PyObject*)o;
}
#define ast2obj_singleton ast2obj_object
#define ast2obj_constant ast2obj_object
#define ast2obj_identifier ast2obj_object
#define ast2obj_string ast2obj_object
#define ast2obj_bytes ast2obj_object

static PyObject* ast2obj_int(long b)
{
 return PyLong_FromLong(b);
}

/* Conversion Python -> AST */

static int obj2ast_object(PyObject* obj, PyObject** out, PyArena* arena)
{
 if (obj == Py_None)
 obj = NULL;
 if (obj) {
 if (PyArena_AddPyObject(arena, obj) < 0) {
 *out = NULL;
 return -1;
 }
 Py_INCREF(obj);
 }
 *out = obj;
 return 0;
}

static int obj2ast_constant(PyObject* obj, PyObject** out, PyArena* arena)
{
 if (PyArena_AddPyObject(arena, obj) < 0) {
 *out = NULL;
 return -1;
 }
 Py_INCREF(obj);
 *out = obj;
 return 0;
}

static int obj2ast_identifier(PyObject* obj, PyObject** out, PyArena* arena)
{
 if (!PyUnicode_CheckExact(obj) && obj != Py_None) {
 PyErr_SetString(PyExc_TypeError, "AST identifier must be of type str");
 return 1;
 }
 return obj2ast_object(obj, out, arena);
}

static int obj2ast_string(PyObject* obj, PyObject** out, PyArena* arena)
{
 if (!PyUnicode_CheckExact(obj) && !PyBytes_CheckExact(obj)) {
 PyErr_SetString(PyExc_TypeError, "AST string must be of type str");
 return 1;
 }
 return obj2ast_object(obj, out, arena);
}

static int obj2ast_int(PyObject* obj, int* out, PyArena* arena)
{
 int i;
 if (!PyLong_Check(obj)) {
 PyErr_Format(PyExc_ValueError, "invalid integer value: %R", obj);
 return 1;
 }

 i = _PyLong_AsInt(obj);
 if (i == -1 && PyErr_Occurred())
 return 1;
 *out = i;
 return 0;
}

static int add_ast_fields(void)
{
 PyObject *empty_tuple, *d;
 if (PyType_Ready(&AST_type) < 0)
 return -1;
 d = AST_type.tp_dict;
 empty_tuple = PyTuple_New(0);
 if (!empty_tuple ||
 _PyDict_SetItemId(d, &PyId__fields, empty_tuple) < 0 ||
 _PyDict_SetItemId(d, &PyId__attributes, empty_tuple) < 0) {
 Py_XDECREF(empty_tuple);
 return -1;
 }
 Py_DECREF(empty_tuple);
 return 0;
}

""", 0, reflow=False)

 self.emit("static int init_types(void)",0)
 self.emit("{", 0)
 self.emit("static int initialized;", 1)
 self.emit("if (initialized) return 1;", 1)
 self.emit("if (add_ast_fields() < 0) return 0;", 1)
 for dfn in mod.dfns:
 self.visit(dfn)
 self.emit("initialized = 1;", 1)
 self.emit("return 1;", 1);
 self.emit("}", 0)

 def visitProduct(self, prod, name):
 if prod.fields:
 fields = name+"_fields"
 else:
 fields = "NULL"
 self.emit('%s_type = make_type("%s", &AST_type, %s, %d);' %
 (name, name, fields, len(prod.fields)), 1)
 self.emit("if (!%s_type) return 0;" % name, 1)
 if prod.attributes:
 self.emit("if (!add_attributes(%s_type, %s_attributes, %d)) return 0;" %
 (name, name, len(prod.attributes)), 1)
 else:
 self.emit("if (!add_attributes(%s_type, NULL, 0)) return 0;" % name, 1)

 def visitSum(self, sum, name):
 self.emit('%s_type = make_type("%s", &AST_type, NULL, 0);' %
 (name, name), 1)
 self.emit("if (!%s_type) return 0;" % name, 1)
 if sum.attributes:
 self.emit("if (!add_attributes(%s_type, %s_attributes, %d)) return 0;" %
 (name, name, len(sum.attributes)), 1)
 else:
 self.emit("if (!add_attributes(%s_type, NULL, 0)) return 0;" % name, 1)
 simple = is_simple(sum)
 for t in sum.types:
 self.visitConstructor(t, name, simple)

 def visitConstructor(self, cons, name, simple):
 if cons.fields:
 fields = cons.name+"_fields"
 else:
 fields = "NULL"
 self.emit('%s_type = make_type("%s", %s_type, %s, %d);' %
 (cons.name, cons.name, name, fields, len(cons.fields)), 1)
 self.emit("if (!%s_type) return 0;" % cons.name, 1)
 if simple:
 self.emit("%s_singleton = PyType_GenericNew(%s_type, NULL, NULL);" %
 (cons.name, cons.name), 1)
 self.emit("if (!%s_singleton) return 0;" % cons.name, 1)


class ASTModuleVisitor(PickleVisitor):

 def visitModule(self, mod):
 self.emit("static struct PyModuleDef _astmodule = {", 0)
 self.emit(' PyModuleDef_HEAD_INIT, "_ast"', 0)
 self.emit("};", 0)
 self.emit("PyMODINIT_FUNC", 0)
 self.emit("PyInit__ast(void)", 0)
 self.emit("{", 0)
 self.emit("PyObject *m, *d;", 1)
 self.emit("if (!init_types()) return NULL;", 1)
 self.emit('m = PyModule_Create(&_astmodule);', 1)
 self.emit("if (!m) return NULL;", 1)
 self.emit("d = PyModule_GetDict(m);", 1)
 self.emit('if (PyDict_SetItemString(d, "AST", (PyObject*)&AST_type) < 0) return NULL;', 1)
 self.emit('if (PyModule_AddIntMacro(m, PyCF_ALLOW_TOP_LEVEL_AWAIT) < 0)', 1)
 self.emit("return NULL;", 2)
 self.emit('if (PyModule_AddIntMacro(m, PyCF_ONLY_AST) < 0)', 1)
 self.emit("return NULL;", 2)
 self.emit('if (PyModule_AddIntMacro(m, PyCF_TYPE_COMMENTS) < 0)', 1)
 self.emit("return NULL;", 2)
 for dfn in mod.dfns:
 self.visit(dfn)
 self.emit("return m;", 1)
 self.emit("}", 0)

 def visitProduct(self, prod, name):
 self.addObj(name)

 def visitSum(self, sum, name):
 self.addObj(name)
 for t in sum.types:
 self.visitConstructor(t, name)

 def visitConstructor(self, cons, name):
 self.addObj(cons.name)

 def addObj(self, name):
 self.emit('if (PyDict_SetItemString(d, "%s", (PyObject*)%s_type) < 0) return NULL;' % (name, name), 1)


_SPECIALIZED_SEQUENCES = ('stmt', 'expr')

def find_sequence(fields, doing_specialization):
 """Return True if any field uses a sequence."""
 for f in fields:
 if f.seq:
 if not doing_specialization:
 return True
 if str(f.type) not in _SPECIALIZED_SEQUENCES:
 return True
 return False

def has_sequence(types, doing_specialization):
 for t in types:
 if find_sequence(t.fields, doing_specialization):
 return True
 return False


class StaticVisitor(PickleVisitor):
 CODE = '''Very simple, always emit this static code. Override CODE'''

 def visit(self, object):
 self.emit(self.CODE, 0, reflow=False)


class ObjVisitor(PickleVisitor):

 def func_begin(self, name):
 ctype = get_c_type(name)
 self.emit("PyObject*", 0)
 self.emit("ast2obj_%s(void* _o)" % (name), 0)
 self.emit("{", 0)
 self.emit("%s o = (%s)_o;" % (ctype, ctype), 1)
 self.emit("PyObject *result = NULL, *value = NULL;", 1)
 self.emit('if (!o) {', 1)
 self.emit("Py_RETURN_NONE;", 2)
 self.emit("}", 1)
 self.emit('', 0)

 def func_end(self):
 self.emit("return result;", 1)
 self.emit("failed:", 0)
 self.emit("Py_XDECREF(value);", 1)
 self.emit("Py_XDECREF(result);", 1)
 self.emit("return NULL;", 1)
 self.emit("}", 0)
 self.emit("", 0)

 def visitSum(self, sum, name):
 if is_simple(sum):
 self.simpleSum(sum, name)
 return
 self.func_begin(name)
 self.emit("switch (o->kind) {", 1)
 for i in range(len(sum.types)):
 t = sum.types[i]
 self.visitConstructor(t, i + 1, name)
 self.emit("}", 1)
 for a in sum.attributes:
 self.emit("value = ast2obj_%s(o->%s);" % (a.type, a.name), 1)
 self.emit("if (!value) goto failed;", 1)
 self.emit('if (_PyObject_SetAttrId(result, &PyId_%s, value) < 0)' % a.name, 1)
 self.emit('goto failed;', 2)
 self.emit('Py_DECREF(value);', 1)
 self.func_end()

 def simpleSum(self, sum, name):
 self.emit("PyObject* ast2obj_%s(%s_ty o)" % (name, name), 0)
 self.emit("{", 0)
 self.emit("switch(o) {", 1)
 for t in sum.types:
 self.emit("case %s:" % t.name, 2)
 self.emit("Py_INCREF(%s_singleton);" % t.name, 3)
 self.emit("return %s_singleton;" % t.name, 3)
 self.emit("default:", 2)
 self.emit('/* should never happen, but just in case ... */', 3)
 code = "PyErr_Format(PyExc_SystemError, \"unknown %s found\");" % name
 self.emit(code, 3, reflow=False)
 self.emit("return NULL;", 3)
 self.emit("}", 1)
 self.emit("}", 0)

 def visitProduct(self, prod, name):
 self.func_begin(name)
 self.emit("result = PyType_GenericNew(%s_type, NULL, NULL);" % name, 1);
 self.emit("if (!result) return NULL;", 1)
 for field in prod.fields:
 self.visitField(field, name, 1, True)
 for a in prod.attributes:
 self.emit("value = ast2obj_%s(o->%s);" % (a.type, a.name), 1)
 self.emit("if (!value) goto failed;", 1)
 self.emit('if (_PyObject_SetAttrId(result, &PyId_%s, value) < 0)' % a.name, 1)
 self.emit('goto failed;', 2)
 self.emit('Py_DECREF(value);', 1)
 self.func_end()

 def visitConstructor(self, cons, enum, name):
 self.emit("case %s_kind:" % cons.name, 1)
 self.emit("result = PyType_GenericNew(%s_type, NULL, NULL);" % cons.name, 2);
 self.emit("if (!result) goto failed;", 2)
 for f in cons.fields:
 self.visitField(f, cons.name, 2, False)
 self.emit("break;", 2)

 def visitField(self, field, name, depth, product):
 def emit(s, d):
 self.emit(s, depth + d)
 if product:
 value = "o->%s" % field.name
 else:
 value = "o->v.%s.%s" % (name, field.name)
 self.set(field, value, depth)
 emit("if (!value) goto failed;", 0)
 emit('if (_PyObject_SetAttrId(result, &PyId_%s, value) == -1)' % field.name, 0)
 emit("goto failed;", 1)
 emit("Py_DECREF(value);", 0)

 def emitSeq(self, field, value, depth, emit):
 emit("seq = %s;" % value, 0)
 emit("n = asdl_seq_LEN(seq);", 0)
 emit("value = PyList_New(n);", 0)
 emit("if (!value) goto failed;", 0)
 emit("for (i = 0; i < n; i++) {", 0)
 self.set("value", field, "asdl_seq_GET(seq, i)", depth + 1)
 emit("if (!value1) goto failed;", 1)
 emit("PyList_SET_ITEM(value, i, value1);", 1)
 emit("value1 = NULL;", 1)
 emit("}", 0)

 def set(self, field, value, depth):
 if field.seq:
 # XXX should really check for is_simple, but that requires a symbol table
 if field.type == "cmpop":
 # While the sequence elements are stored as void*,
 # ast2obj_cmpop expects an enum
 self.emit("{", depth)
 self.emit("Py_ssize_t i, n = asdl_seq_LEN(%s);" % value, depth+1)
 self.emit("value = PyList_New(n);", depth+1)
 self.emit("if (!value) goto failed;", depth+1)
 self.emit("for(i = 0; i < n; i++)", depth+1)
 # This cannot fail, so no need for error handling
 self.emit("PyList_SET_ITEM(value, i, ast2obj_cmpop((cmpop_ty)asdl_seq_GET(%s, i)));" % value,
 depth+2, reflow=False)
 self.emit("}", depth)
 else:
 self.emit("value = ast2obj_list(%s, ast2obj_%s);" % (value, field.type), depth)
 else:
 ctype = get_c_type(field.type)
 self.emit("value = ast2obj_%s(%s);" % (field.type, value), depth, reflow=False)


class PartingShots(StaticVisitor):

 CODE = """
PyObject* PyAST_mod2obj(mod_ty t)
{
 if (!init_types())
 return NULL;
 return ast2obj_mod(t);
}

/* mode is 0 for "exec", 1 for "eval" and 2 for "single" input */
mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode)
{
 PyObject *req_type[3];
 char *req_name[] = {"Module", "Expression", "Interactive"};
 int isinstance;

 if (PySys_Audit("compile", "OO", ast, Py_None) < 0) {
 return NULL;
 }

 req_type[0] = (PyObject*)Module_type;
 req_type[1] = (PyObject*)Expression_type;
 req_type[2] = (PyObject*)Interactive_type;

 assert(0 <= mode && mode <= 2);

 if (!init_types())
 return NULL;

 isinstance = PyObject_IsInstance(ast, req_type[mode]);
 if (isinstance == -1)
 return NULL;
 if (!isinstance) {
 PyErr_Format(PyExc_TypeError, "expected %s node, got %.400s",
 req_name[mode], Py_TYPE(ast)->tp_name);
 return NULL;
 }

 mod_ty res = NULL;
 if (obj2ast_mod(ast, &res, arena) != 0)
 return NULL;
 else
 return res;
}

int PyAST_Check(PyObject* obj)
{
 if (!init_types())
 return -1;
 return PyObject_IsInstance(obj, (PyObject*)&AST_type);
}
"""

class ChainOfVisitors:
 def __init__(self, *visitors):
 self.visitors = visitors

 def visit(self, object):
 for v in self.visitors:
 v.visit(object)
 v.emit("", 0)

common_msg = "/* File automatically generated by %s. */\n\n"

def main(srcfile, dump_module=False):
 argv0 = sys.argv[0]
 components = argv0.split(os.sep)
 argv0 = os.sep.join(components[-2:])
 auto_gen_msg = common_msg % argv0
 mod = asdl.parse(srcfile)
 if dump_module:
 print('Parsed Module:')
 print(mod)
 if not asdl.check(mod):
 sys.exit(1)
 if H_FILE:
 with open(H_FILE, "w") as f:
 f.write(auto_gen_msg)
 f.write('#ifndef Py_PYTHON_AST_H\n')
 f.write('#define Py_PYTHON_AST_H\n')
 f.write('#ifdef __cplusplus\n')
 f.write('extern "C" {\n')
 f.write('#endif\n')
 f.write('\n')
 f.write('#include "asdl.h"\n')
 f.write('\n')
 f.write('#undef Yield /* undefine macro conflicting with <winbase.h> */\n')
 f.write('\n')
 c = ChainOfVisitors(TypeDefVisitor(f),
 StructVisitor(f))

 c.visit(mod)
 f.write("// Note: these macros affect function definitions, not only call sites.\n")
 PrototypeVisitor(f).visit(mod)
 f.write("\n")
 f.write("PyObject* PyAST_mod2obj(mod_ty t);\n")
 f.write("mod_ty PyAST_obj2mod(PyObject* ast, PyArena* arena, int mode);\n")
 f.write("int PyAST_Check(PyObject* obj);\n")
 f.write('\n')
 f.write('#ifdef __cplusplus\n')
 f.write('}\n')
 f.write('#endif\n')
 f.write('#endif /* !Py_PYTHON_AST_H */\n')

 if C_FILE:
 with open(C_FILE, "w") as f:
 f.write(auto_gen_msg)
 f.write('#include <stddef.h>\n')
 f.write('\n')
 f.write('#include "Python.h"\n')
 f.write('#include "%s-ast.h"\n' % mod.name)
 f.write('\n')
 f.write("static PyTypeObject AST_type;\n")
 v = ChainOfVisitors(
 PyTypesDeclareVisitor(f),
 PyTypesVisitor(f),
 Obj2ModPrototypeVisitor(f),
 FunctionVisitor(f),
 ObjVisitor(f),
 Obj2ModVisitor(f),
 ASTModuleVisitor(f),
 PartingShots(f),
 )
 v.visit(mod)

if __name__ == "__main__":
 import getopt

 H_FILE = ''
 C_FILE = ''
 dump_module = False
 opts, args = getopt.getopt(sys.argv[1:], "dh:c:")
 for o, v in opts:
 if o == '-h':
 H_FILE = v
 elif o == '-c':
 C_FILE = v
 elif o == '-d':
 dump_module = True
 if H_FILE and C_FILE:
 print('Must specify exactly one output file')
 sys.exit(1)
 elif len(args) != 1:
 print('Must specify single input file')
 sys.exit(1)
 main(args[0], dump_module)