gen2.py 34.9 KB
Newer Older
wester committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943
#!/usr/bin/env python

from __future__ import print_function
import hdr_parser, sys, re, os
from string import Template

if sys.version_info[0] >= 3:
    from io import StringIO
else:
    from cStringIO import StringIO

ignored_arg_types = ["RNG*"]

gen_template_check_self = Template("""    if(!PyObject_TypeCheck(self, &pyopencv_${name}_Type))
        return failmsgp("Incorrect type of self (must be '${name}' or its derivative)");
    $cname* _self_ = ${amp}((pyopencv_${name}_t*)self)->v${get};
""")

gen_template_check_self_algo = Template("""    if(!PyObject_TypeCheck(self, &pyopencv_${name}_Type))
        return failmsgp("Incorrect type of self (must be '${name}' or its derivative)");
    $cname* _self_ = dynamic_cast<$cname*>(${amp}((pyopencv_${name}_t*)self)->v.get());
""")

gen_template_call_constructor_prelude = Template("""self = PyObject_NEW(pyopencv_${name}_t, &pyopencv_${name}_Type);
        new (&(self->v)) Ptr<$cname>(); // init Ptr with placement new
        if(self) """)

gen_template_call_constructor = Template("""self->v.reset(new ${cname}${args})""")

gen_template_simple_call_constructor_prelude = Template("""self = PyObject_NEW(pyopencv_${name}_t, &pyopencv_${name}_Type);
        if(self) """)

gen_template_simple_call_constructor = Template("""self->v = ${cname}${args}""")

gen_template_parse_args = Template("""const char* keywords[] = { $kw_list, NULL };
    if( PyArg_ParseTupleAndKeywords(args, kw, "$fmtspec", (char**)keywords, $parse_arglist)$code_cvt )""")

gen_template_func_body = Template("""$code_decl
    $code_parse
    {
        ${code_prelude}ERRWRAP2($code_fcall);
        $code_ret;
    }
""")

py_major_version = sys.version_info[0]
if py_major_version >= 3:
    head_init_str = "PyVarObject_HEAD_INIT(&PyType_Type, 0)"
else:
    head_init_str = """PyObject_HEAD_INIT(&PyType_Type)
0,"""

gen_template_simple_type_decl = Template("""
struct pyopencv_${name}_t
{
    PyObject_HEAD
    ${cname} v;
};

static PyTypeObject pyopencv_${name}_Type =
{
    %s
    MODULESTR".$wname",
    sizeof(pyopencv_${name}_t),
};

static void pyopencv_${name}_dealloc(PyObject* self)
{
    PyObject_Del(self);
}

template<> PyObject* pyopencv_from(const ${cname}& r)
{
    pyopencv_${name}_t *m = PyObject_NEW(pyopencv_${name}_t, &pyopencv_${name}_Type);
    m->v = r;
    return (PyObject*)m;
}

template<> bool pyopencv_to(PyObject* src, ${cname}& dst, const char* name)
{
    if( src == NULL || src == Py_None )
        return true;
    if(!PyObject_TypeCheck(src, &pyopencv_${name}_Type))
    {
        failmsg("Expected ${cname} for argument '%%s'", name);
        return false;
    }
    dst = ((pyopencv_${name}_t*)src)->v;
    return true;
}
""" % head_init_str)


gen_template_type_decl = Template("""
struct pyopencv_${name}_t
{
    PyObject_HEAD
    Ptr<${cname1}> v;
};

static PyTypeObject pyopencv_${name}_Type =
{
    %s
    MODULESTR".$wname",
    sizeof(pyopencv_${name}_t),
};

static void pyopencv_${name}_dealloc(PyObject* self)
{
    ((pyopencv_${name}_t*)self)->v.release();
    PyObject_Del(self);
}

template<> PyObject* pyopencv_from(const Ptr<${cname}>& r)
{
    pyopencv_${name}_t *m = PyObject_NEW(pyopencv_${name}_t, &pyopencv_${name}_Type);
    new (&(m->v)) Ptr<$cname1>(); // init Ptr with placement new
    m->v = r;
    return (PyObject*)m;
}

template<> bool pyopencv_to(PyObject* src, Ptr<${cname}>& dst, const char* name)
{
    if( src == NULL || src == Py_None )
        return true;
    if(!PyObject_TypeCheck(src, &pyopencv_${name}_Type))
    {
        failmsg("Expected ${cname} for argument '%%s'", name);
        return false;
    }
    dst = ((pyopencv_${name}_t*)src)->v.dynamicCast<${cname}>();
    return true;
}

""" % head_init_str)

gen_template_map_type_cvt = Template("""
template<> bool pyopencv_to(PyObject* src, ${cname}& dst, const char* name);
""")

gen_template_set_prop_from_map = Template("""
    if( PyMapping_HasKeyString(src, (char*)"$propname") )
    {
        tmp = PyMapping_GetItemString(src, (char*)"$propname");
        ok = tmp && pyopencv_to(tmp, dst.$propname);
        Py_DECREF(tmp);
        if(!ok) return false;
    }""")

gen_template_type_impl = Template("""
static PyObject* pyopencv_${name}_repr(PyObject* self)
{
    char str[1000];
    sprintf(str, "<$wname %p>", self);
    return PyString_FromString(str);
}

${getset_code}

static PyGetSetDef pyopencv_${name}_getseters[] =
{${getset_inits}
    {NULL}  /* Sentinel */
};

${methods_code}

static PyMethodDef pyopencv_${name}_methods[] =
{
${methods_inits}
    {NULL,          NULL}
};

static void pyopencv_${name}_specials(void)
{
    pyopencv_${name}_Type.tp_base = ${baseptr};
    pyopencv_${name}_Type.tp_dealloc = pyopencv_${name}_dealloc;
    pyopencv_${name}_Type.tp_repr = pyopencv_${name}_repr;
    pyopencv_${name}_Type.tp_getset = pyopencv_${name}_getseters;
    pyopencv_${name}_Type.tp_methods = pyopencv_${name}_methods;${extra_specials}
}
""")


gen_template_get_prop = Template("""
static PyObject* pyopencv_${name}_get_${member}(pyopencv_${name}_t* p, void *closure)
{
    return pyopencv_from(p->v${access}${member});
}
""")

gen_template_get_prop_algo = Template("""
static PyObject* pyopencv_${name}_get_${member}(pyopencv_${name}_t* p, void *closure)
{
    return pyopencv_from(dynamic_cast<$cname*>(p->v.get())${access}${member});
}
""")

gen_template_set_prop = Template("""
static int pyopencv_${name}_set_${member}(pyopencv_${name}_t* p, PyObject *value, void *closure)
{
    if (value == NULL)
    {
        PyErr_SetString(PyExc_TypeError, "Cannot delete the ${member} attribute");
        return -1;
    }
    return pyopencv_to(value, p->v${access}${member}) ? 0 : -1;
}
""")

gen_template_set_prop_algo = Template("""
static int pyopencv_${name}_set_${member}(pyopencv_${name}_t* p, PyObject *value, void *closure)
{
    if (value == NULL)
    {
        PyErr_SetString(PyExc_TypeError, "Cannot delete the ${member} attribute");
        return -1;
    }
    return pyopencv_to(value, dynamic_cast<$cname*>(p->v.get())${access}${member}) ? 0 : -1;
}
""")


gen_template_prop_init = Template("""
    {(char*)"${member}", (getter)pyopencv_${name}_get_${member}, NULL, (char*)"${member}", NULL},""")

gen_template_rw_prop_init = Template("""
    {(char*)"${member}", (getter)pyopencv_${name}_get_${member}, (setter)pyopencv_${name}_set_${member}, (char*)"${member}", NULL},""")

simple_argtype_mapping = {
    "bool": ("bool", "b", "0"),
    "int": ("int", "i", "0"),
    "float": ("float", "f", "0.f"),
    "double": ("double", "d", "0"),
    "c_string": ("char*", "s", '(char*)""')
}

def normalize_class_name(name):
    return re.sub(r"^cv\.", "", name).replace(".", "_")

class ClassProp(object):
    def __init__(self, decl):
        self.tp = decl[0].replace("*", "_ptr")
        self.name = decl[1]
        self.readonly = True
        if "/RW" in decl[3]:
            self.readonly = False

class ClassInfo(object):
    def __init__(self, name, decl=None):
        self.cname = name.replace(".", "::")
        self.name = self.wname = normalize_class_name(name)
        self.ismap = False
        self.issimple = False
        self.isalgorithm = False
        self.methods = {}
        self.props = []
        self.consts = {}
        self.base = None
        customname = False

        if decl:
            bases = decl[1].split()[1:]
            if len(bases) > 1:
                print("Note: Class %s has more than 1 base class (not supported by Python C extensions)" % (self.name,))
                print("      Bases: ", " ".join(bases))
                print("      Only the first base class will be used")
                #return sys.exit(-1)
            elif len(bases) == 1:
                self.base = bases[0].strip(",")
                if self.base.startswith("cv::"):
                    self.base = self.base[4:]
                if self.base == "Algorithm":
                    self.isalgorithm = True
                self.base = self.base.replace("::", "_")

            for m in decl[2]:
                if m.startswith("="):
                    self.wname = m[1:]
                    customname = True
                elif m == "/Map":
                    self.ismap = True
                elif m == "/Simple":
                    self.issimple = True
            self.props = [ClassProp(p) for p in decl[3]]

        if not customname and self.wname.startswith("Cv"):
            self.wname = self.wname[2:]

    def gen_map_code(self, all_classes):
        code = "static bool pyopencv_to(PyObject* src, %s& dst, const char* name)\n{\n    PyObject* tmp;\n    bool ok;\n" % (self.cname)
        code += "".join([gen_template_set_prop_from_map.substitute(propname=p.name,proptype=p.tp) for p in self.props])
        if self.base:
            code += "\n    return pyopencv_to(src, (%s&)dst, name);\n}\n" % all_classes[self.base].cname
        else:
            code += "\n    return true;\n}\n"
        return code

    def gen_code(self, all_classes):
        if self.ismap:
            return self.gen_map_code(all_classes)

        getset_code = StringIO()
        getset_inits = StringIO()

        sorted_props = [(p.name, p) for p in self.props]
        sorted_props.sort()

        access_op = "->"
        if self.issimple:
            access_op = "."

        for pname, p in sorted_props:
            if self.isalgorithm:
                getset_code.write(gen_template_get_prop_algo.substitute(name=self.name, cname=self.cname, member=pname, membertype=p.tp, access=access_op))
            else:
                getset_code.write(gen_template_get_prop.substitute(name=self.name, member=pname, membertype=p.tp, access=access_op))
            if p.readonly:
                getset_inits.write(gen_template_prop_init.substitute(name=self.name, member=pname))
            else:
                if self.isalgorithm:
                    getset_code.write(gen_template_set_prop_algo.substitute(name=self.name, cname=self.cname, member=pname, membertype=p.tp, access=access_op))
                else:
                    getset_code.write(gen_template_set_prop.substitute(name=self.name, member=pname, membertype=p.tp, access=access_op))
                getset_inits.write(gen_template_rw_prop_init.substitute(name=self.name, member=pname))

        methods_code = StringIO()
        methods_inits = StringIO()

        sorted_methods = list(self.methods.items())
        sorted_methods.sort()

        for mname, m in sorted_methods:
            methods_code.write(m.gen_code(all_classes))
            methods_inits.write(m.get_tab_entry())

        baseptr = "NULL"
        if self.base and self.base in all_classes:
            baseptr = "&pyopencv_" + all_classes[self.base].name + "_Type"

        code = gen_template_type_impl.substitute(name=self.name, wname=self.wname, cname=self.cname,
            getset_code=getset_code.getvalue(), getset_inits=getset_inits.getvalue(),
            methods_code=methods_code.getvalue(), methods_inits=methods_inits.getvalue(),
            baseptr=baseptr, extra_specials="")

        return code


def handle_ptr(tp):
    if tp.startswith('Ptr_'):
        tp = 'Ptr<' + "::".join(tp.split('_')[1:]) + '>'
    return tp


class ArgInfo(object):
    def __init__(self, arg_tuple):
        self.tp = handle_ptr(arg_tuple[0])
        self.name = arg_tuple[1]
        self.defval = arg_tuple[2]
        self.isarray = False
        self.arraylen = 0
        self.arraycvt = None
        self.inputarg = True
        self.outputarg = False
        self.returnarg = False
        for m in arg_tuple[3]:
            if m == "/O":
                self.inputarg = False
                self.outputarg = True
                self.returnarg = True
            elif m == "/IO":
                self.inputarg = True
                self.outputarg = True
                self.returnarg = True
            elif m.startswith("/A"):
                self.isarray = True
                self.arraylen = m[2:].strip()
            elif m.startswith("/CA"):
                self.isarray = True
                self.arraycvt = m[2:].strip()
        self.py_inputarg = False
        self.py_outputarg = False

    def isbig(self):
        return self.tp == "Mat" or self.tp == "vector_Mat"# or self.tp.startswith("vector")

    def crepr(self):
        return "ArgInfo(\"%s\", %d)" % (self.name, self.outputarg)


class FuncVariant(object):
    def __init__(self, classname, name, decl, isconstructor):
        self.classname = classname
        self.name = self.wname = name
        self.isconstructor = isconstructor

        self.rettype = decl[4] if len(decl) >=5 else handle_ptr(decl[1])
        if self.rettype == "void":
            self.rettype = ""
        self.args = []
        self.array_counters = {}
        for a in decl[3]:
            ainfo = ArgInfo(a)
            if ainfo.isarray and not ainfo.arraycvt:
                c = ainfo.arraylen
                c_arrlist = self.array_counters.get(c, [])
                if c_arrlist:
                    c_arrlist.append(ainfo.name)
                else:
                    self.array_counters[c] = [ainfo.name]
            self.args.append(ainfo)
        self.init_pyproto()

    def init_pyproto(self):
        # string representation of argument list, with '[', ']' symbols denoting optional arguments, e.g.
        # "src1, src2[, dst[, mask]]" for cv.add
        argstr = ""

        # list of all input arguments of the Python function, with the argument numbers:
        #    [("src1", 0), ("src2", 1), ("dst", 2), ("mask", 3)]
        # we keep an argument number to find the respective argument quickly, because
        # some of the arguments of C function may not present in the Python function (such as array counters)
        # or even go in a different order ("heavy" output parameters of the C function
        # become the first optional input parameters of the Python function, and thus they are placed right after
        # non-optional input parameters)
        arglist = []

        # the list of "heavy" output parameters. Heavy parameters are the parameters
        # that can be expensive to allocate each time, such as vectors and matrices (see isbig).
        outarr_list = []

        # the list of output parameters. Also includes input/output parameters.
        outlist = []

        firstoptarg = 1000000
        argno = -1
        for a in self.args:
            argno += 1
            if a.name in self.array_counters:
                continue
            if a.tp in ignored_arg_types:
                continue
            if a.returnarg:
                outlist.append((a.name, argno))
            if (not a.inputarg) and a.isbig():
                outarr_list.append((a.name, argno))
                continue
            if not a.inputarg:
                continue
            if not a.defval:
                arglist.append((a.name, argno))
            else:
                firstoptarg = min(firstoptarg, len(arglist))
                # if there are some array output parameters before the first default parameter, they
                # are added as optional parameters before the first optional parameter
                if outarr_list:
                    arglist += outarr_list
                    outarr_list = []
                arglist.append((a.name, argno))

        if outarr_list:
            firstoptarg = min(firstoptarg, len(arglist))
            arglist += outarr_list
        firstoptarg = min(firstoptarg, len(arglist))

        noptargs = len(arglist) - firstoptarg
        argnamelist = [aname for aname, argno in arglist]
        argstr = ", ".join(argnamelist[:firstoptarg])
        argstr = "[, ".join([argstr] + argnamelist[firstoptarg:])
        argstr += "]" * noptargs
        if self.rettype:
            outlist = [("retval", -1)] + outlist
        elif self.isconstructor:
            assert outlist == []
            outlist = [("self", -1)]
        if self.isconstructor:
            classname = self.classname
            if classname.startswith("Cv"):
                classname=classname[2:]
            outstr = "<%s object>" % (classname,)
        elif outlist:
            outstr = ", ".join([o[0] for o in outlist])
        else:
            outstr = "None"

        self.py_docstring = "%s(%s) -> %s" % (self.wname, argstr, outstr)
        self.py_noptargs = noptargs
        self.py_arglist = arglist
        for aname, argno in arglist:
            self.args[argno].py_inputarg = True
        for aname, argno in outlist:
            if argno >= 0:
                self.args[argno].py_outputarg = True
        self.py_outlist = outlist


class FuncInfo(object):
    def __init__(self, classname, name, cname, isconstructor, namespace):
        self.classname = classname
        self.name = name
        self.cname = cname
        self.isconstructor = isconstructor
        self.namespace = namespace
        self.variants = []

    def add_variant(self, decl):
        self.variants.append(FuncVariant(self.classname, self.name, decl, self.isconstructor))

    def get_wrapper_name(self):
        name = self.name
        if self.classname:
            classname = self.classname + "_"
            if "[" in name:
                name = "getelem"
        else:
            classname = ""
        return "pyopencv_" + self.namespace.replace('.','_') + '_' + classname + name

    def get_wrapper_prototype(self):
        full_fname = self.get_wrapper_name()
        if self.classname and not self.isconstructor:
            self_arg = "self"
        else:
            self_arg = ""
        return "static PyObject* %s(PyObject* %s, PyObject* args, PyObject* kw)" % (full_fname, self_arg)

    def get_tab_entry(self):
        docstring_list = []
        have_empty_constructor = False
        for v in self.variants:
            s = v.py_docstring
            if (not v.py_arglist) and self.isconstructor:
                have_empty_constructor = True
            if s not in docstring_list:
                docstring_list.append(s)
        # if there are just 2 constructors: default one and some other,
        # we simplify the notation.
        # Instead of ClassName(args ...) -> object or ClassName() -> object
        # we write ClassName([args ...]) -> object
        if have_empty_constructor and len(self.variants) == 2:
            idx = self.variants[1].py_arglist != []
            s = self.variants[idx].py_docstring
            p1 = s.find("(")
            p2 = s.rfind(")")
            docstring_list = [s[:p1+1] + "[" + s[p1+1:p2] + "]" + s[p2:]]

        return Template('    {"$py_funcname", (PyCFunction)$wrap_funcname, METH_VARARGS | METH_KEYWORDS, "$py_docstring"},\n'
                        ).substitute(py_funcname = self.variants[0].wname, wrap_funcname=self.get_wrapper_name(),
                                     py_docstring = "  or  ".join(docstring_list))

    def gen_code(self, all_classes):
        proto = self.get_wrapper_prototype()
        code = "%s\n{\n" % (proto,)
        code += "    using namespace %s;\n\n" % self.namespace.replace('.', '::')

        selfinfo = ClassInfo("")
        ismethod = self.classname != "" and not self.isconstructor
        # full name is needed for error diagnostic in PyArg_ParseTupleAndKeywords
        fullname = self.name

        if self.classname:
            selfinfo = all_classes[self.classname]
            if not self.isconstructor:
                amp = "&" if selfinfo.issimple else ""
                if selfinfo.isalgorithm:
                    code += gen_template_check_self_algo.substitute(name=selfinfo.name, cname=selfinfo.cname, amp=amp)
                else:
                    get = "" if selfinfo.issimple else ".get()"
                    code += gen_template_check_self.substitute(name=selfinfo.name, cname=selfinfo.cname, amp=amp, get=get)
                fullname = selfinfo.wname + "." + fullname

        all_code_variants = []
        declno = -1
        for v in self.variants:
            code_decl = ""
            code_ret = ""
            code_cvt_list = []

            code_args = "("
            all_cargs = []
            parse_arglist = []

            # declare all the C function arguments,
            # add necessary conversions from Python objects to code_cvt_list,
            # form the function/method call,
            # for the list of type mappings
            for a in v.args:
                if a.tp in ignored_arg_types:
                    defval = a.defval
                    if not defval and a.tp.endswith("*"):
                        defval = 0
                    assert defval
                    if not code_args.endswith("("):
                        code_args += ", "
                    code_args += defval
                    all_cargs.append([[None, ""], ""])
                    continue
                tp1 = tp = a.tp
                amp = ""
                defval0 = ""
                if tp.endswith("*"):
                    tp = tp1 = tp[:-1]
                    amp = "&"
                    if tp.endswith("*"):
                        defval0 = "0"
                        tp1 = tp.replace("*", "_ptr")
                if tp1.endswith("*"):
                    print("Error: type with star: a.tp=%s, tp=%s, tp1=%s" % (a.tp, tp, tp1))
                    sys.exit(-1)

                amapping = simple_argtype_mapping.get(tp, (tp, "O", defval0))
                parse_name = a.name
                if a.py_inputarg:
                    if amapping[1] == "O":
                        code_decl += "    PyObject* pyobj_%s = NULL;\n" % (a.name,)
                        parse_name = "pyobj_" + a.name
                        if a.tp == 'char':
                            code_cvt_list.append("convert_to_char(pyobj_%s, &%s, %s)"% (a.name, a.name, a.crepr()))
                        else:
                            code_cvt_list.append("pyopencv_to(pyobj_%s, %s, %s)" % (a.name, a.name, a.crepr()))

                all_cargs.append([amapping, parse_name])

                defval = a.defval
                if not defval:
                    defval = amapping[2]
                # "tp arg = tp();" is equivalent to "tp arg;" in the case of complex types
                if defval == tp + "()" and amapping[1] == "O":
                    defval = ""
                if a.outputarg and not a.inputarg:
                    defval = ""
                if defval:
                    code_decl += "    %s %s=%s;\n" % (amapping[0], a.name, defval)
                else:
                    code_decl += "    %s %s;\n" % (amapping[0], a.name)

                if not code_args.endswith("("):
                    code_args += ", "
                code_args += amp + a.name

            code_args += ")"

            if self.isconstructor:
                code_decl += "    pyopencv_%s_t* self = 0;\n" % selfinfo.name
                if selfinfo.issimple:
                    templ_prelude = gen_template_simple_call_constructor_prelude
                    templ = gen_template_simple_call_constructor
                else:
                    templ_prelude = gen_template_call_constructor_prelude
                    templ = gen_template_call_constructor

                code_prelude = templ_prelude.substitute(name=selfinfo.name, cname=selfinfo.cname)
                code_fcall = templ.substitute(name=selfinfo.name, cname=selfinfo.cname, args=code_args)
            else:
                code_prelude = ""
                code_fcall = ""
                if v.rettype:
                    code_decl += "    " + v.rettype + " retval;\n"
                    code_fcall += "retval = "
                if ismethod:
                    code_fcall += "_self_->" + self.cname
                else:
                    code_fcall += self.cname
                code_fcall += code_args

            if code_cvt_list:
                code_cvt_list = [""] + code_cvt_list

            # add info about return value, if any, to all_cargs. if there non-void return value,
            # it is encoded in v.py_outlist as ("retval", -1) pair.
            # As [-1] in Python accesses the last element of a list, we automatically handle the return value by
            # adding the necessary info to the end of all_cargs list.
            if v.rettype:
                tp = v.rettype
                tp1 = tp.replace("*", "_ptr")
                amapping = simple_argtype_mapping.get(tp, (tp, "O", "0"))
                all_cargs.append(amapping)

            if v.args and v.py_arglist:
                # form the format spec for PyArg_ParseTupleAndKeywords
                fmtspec = "".join([all_cargs[argno][0][1] for aname, argno in v.py_arglist])
                if v.py_noptargs > 0:
                    fmtspec = fmtspec[:-v.py_noptargs] + "|" + fmtspec[-v.py_noptargs:]
                fmtspec += ":" + fullname

                # form the argument parse code that:
                #   - declares the list of keyword parameters
                #   - calls PyArg_ParseTupleAndKeywords
                #   - converts complex arguments from PyObject's to native OpenCV types
                code_parse = gen_template_parse_args.substitute(
                    kw_list = ", ".join(['"' + aname + '"' for aname, argno in v.py_arglist]),
                    fmtspec = fmtspec,
                    parse_arglist = ", ".join(["&" + all_cargs[argno][1] for aname, argno in v.py_arglist]),
                    code_cvt = " &&\n        ".join(code_cvt_list))
            else:
                code_parse = "if(PyObject_Size(args) == 0 && (kw == NULL || PyObject_Size(kw) == 0))"

            if len(v.py_outlist) == 0:
                code_ret = "Py_RETURN_NONE"
            elif len(v.py_outlist) == 1:
                if self.isconstructor:
                    code_ret = "return (PyObject*)self"
                else:
                    aname, argno = v.py_outlist[0]
                    code_ret = "return pyopencv_from(%s)" % (aname,)
            else:
                # ther is more than 1 return parameter; form the tuple out of them
                fmtspec = "N"*len(v.py_outlist)
                backcvt_arg_list = []
                for aname, argno in v.py_outlist:
                    amapping = all_cargs[argno][0]
                    backcvt_arg_list.append("%s(%s)" % (amapping[2], aname))
                code_ret = "return Py_BuildValue(\"(%s)\", %s)" % \
                    (fmtspec, ", ".join(["pyopencv_from(" + aname + ")" for aname, argno in v.py_outlist]))

            all_code_variants.append(gen_template_func_body.substitute(code_decl=code_decl,
                code_parse=code_parse, code_prelude=code_prelude, code_fcall=code_fcall, code_ret=code_ret))

        if len(all_code_variants)==1:
            # if the function/method has only 1 signature, then just put it
            code += all_code_variants[0]
        else:
            # try to execute each signature
            code += "    PyErr_Clear();\n\n".join(["    {\n" + v + "    }\n" for v in all_code_variants])
        code += "\n    return NULL;\n}\n\n"
        return code


class Namespace(object):
    def __init__(self):
        self.funcs = {}
        self.consts = {}


class PythonWrapperGenerator(object):
    def __init__(self):
        self.clear()

    def clear(self):
        self.classes = {}
        self.namespaces = {}
        self.consts = {}
        self.code_include = StringIO()
        self.code_types = StringIO()
        self.code_funcs = StringIO()
        self.code_type_reg = StringIO()
        self.code_ns_reg = StringIO()
        self.class_idx = 0

    def add_class(self, stype, name, decl):
        classinfo = ClassInfo(name, decl)
        classinfo.decl_idx = self.class_idx
        self.class_idx += 1

        if classinfo.name in self.classes:
            print("Generator error: class %s (cname=%s) already exists" \
                % (classinfo.name, classinfo.cname))
            sys.exit(-1)
        self.classes[classinfo.name] = classinfo

    def split_decl_name(self, name):
        chunks = name.split('.')
        namespace = chunks[:-1]
        classes = []
        while namespace and '.'.join(namespace) not in self.parser.namespaces:
            classes.insert(0, namespace.pop())
        return namespace, classes, chunks[-1]


    def add_const(self, name, decl):
        cname = name.replace('.','::')
        namespace, classes, name = self.split_decl_name(name)
        namespace = '.'.join(namespace)
        name = '_'.join(classes+[name])
        ns = self.namespaces.setdefault(namespace, Namespace())
        if name in ns.consts:
            print("Generator error: constant %s (cname=%s) already exists" \
                % (name, cname))
            sys.exit(-1)
        ns.consts[name] = cname

    def add_func(self, decl):
        namespace, classes, barename = self.split_decl_name(decl[0])
        cname = "::".join(namespace+classes+[barename])
        name = barename
        classname = ''
        bareclassname = ''
        if classes:
            classname = normalize_class_name('.'.join(namespace+classes))
            bareclassname = classes[-1]
        namespace = '.'.join(namespace)

        isconstructor = name == bareclassname
        isclassmethod = False
        for m in decl[2]:
            if m == "/S":
                isclassmethod = True
            elif m.startswith("="):
                name = m[1:]
        if isclassmethod:
            name = "_".join(classes+[name])
            classname = ''
        elif isconstructor:
            name = "_".join(classes[:-1]+[name])

        if classname and not isconstructor:
            cname = barename
            func_map = self.classes[classname].methods
        else:
            func_map = self.namespaces.setdefault(namespace, Namespace()).funcs

        func = func_map.setdefault(name, FuncInfo(classname, name, cname, isconstructor, namespace))
        func.add_variant(decl)


    def gen_namespace(self, ns_name):
        ns = self.namespaces[ns_name]
        wname = normalize_class_name(ns_name)

        self.code_ns_reg.write('static PyMethodDef methods_%s[] = {\n'%wname)
        for name, func in sorted(ns.funcs.items()):
            self.code_ns_reg.write(func.get_tab_entry())
        self.code_ns_reg.write('    {NULL, NULL}\n};\n\n')

        self.code_ns_reg.write('static ConstDef consts_%s[] = {\n'%wname)
        for name, cname in sorted(ns.consts.items()):
            self.code_ns_reg.write('    {"%s", %s},\n'%(name, cname))
            compat_name = re.sub(r"([a-z])([A-Z])", r"\1_\2", name).upper()
            if name != compat_name:
                self.code_ns_reg.write('    {"%s", %s},\n'%(compat_name, cname))
        self.code_ns_reg.write('    {NULL, 0}\n};\n\n')

    def gen_namespaces_reg(self):
        self.code_ns_reg.write('static void init_submodules(PyObject * root) \n{\n')
        for ns_name in sorted(self.namespaces):
            if ns_name.split('.')[0] == 'cv':
                wname = normalize_class_name(ns_name)
                self.code_ns_reg.write('  init_submodule(root, MODULESTR"%s", methods_%s, consts_%s);\n' % (ns_name[2:], wname, wname))
        self.code_ns_reg.write('};\n')


    def save(self, path, name, buf):
        f = open(path + "/" + name, "wt")
        f.write(buf.getvalue())
        f.close()

    def gen(self, srcfiles, output_path):
        self.clear()
        self.parser = hdr_parser.CppHeaderParser()

        # step 1: scan the headers and build more descriptive maps of classes, consts, functions
        for hdr in srcfiles:
            decls = self.parser.parse(hdr)
            if len(decls) == 0:
                continue
            self.code_include.write( '#include "{0}"\n'.format(hdr[hdr.rindex('opencv2/'):]) )
            for decl in decls:
                name = decl[0]
                if name.startswith("struct") or name.startswith("class"):
                    # class/struct
                    p = name.find(" ")
                    stype = name[:p]
                    name = name[p+1:].strip()
                    self.add_class(stype, name, decl)
                elif name.startswith("const"):
                    # constant
                    self.add_const(name.replace("const ", "").strip(), decl)
                else:
                    # function
                    self.add_func(decl)

        # step 1.5 check if all base classes exist
        for name, classinfo in self.classes.items():
            if classinfo.base:
                chunks = classinfo.base.split('_')
                base = '_'.join(chunks)
                while base not in self.classes and len(chunks)>1:
                    del chunks[-2]
                    base = '_'.join(chunks)
                if base not in self.classes:
                    print("Generator error: unable to resolve base %s for %s"
                        % (classinfo.base, classinfo.name))
                    sys.exit(-1)
                classinfo.base = base
                classinfo.isalgorithm |= self.classes[base].isalgorithm
                self.classes[name] = classinfo

        # step 2: generate code for the classes and their methods
        classlist = list(self.classes.items())
        classlist.sort()
        for name, classinfo in classlist:
            if classinfo.ismap:
                self.code_types.write(gen_template_map_type_cvt.substitute(name=name, cname=classinfo.cname))
            else:
                if classinfo.issimple:
                    templ = gen_template_simple_type_decl
                else:
                    templ = gen_template_type_decl
                self.code_types.write(templ.substitute(name=name, wname=classinfo.wname, cname=classinfo.cname,
                                      cname1=("cv::Algorithm" if classinfo.isalgorithm else classinfo.cname)))

        # register classes in the same order as they have been declared.
        # this way, base classes will be registered in Python before their derivatives.
        classlist1 = [(classinfo.decl_idx, name, classinfo) for name, classinfo in classlist]
        classlist1.sort()

        for decl_idx, name, classinfo in classlist1:
            code = classinfo.gen_code(self.classes)
            self.code_types.write(code)
            if not classinfo.ismap:
                self.code_type_reg.write("MKTYPE2(%s);\n" % (classinfo.name,) )

        # step 3: generate the code for all the global functions
        for ns_name, ns in sorted(self.namespaces.items()):
            if ns_name.split('.')[0] != 'cv':
                continue
            for name, func in sorted(ns.funcs.items()):
                code = func.gen_code(self.classes)
                self.code_funcs.write(code)
            self.gen_namespace(ns_name)
        self.gen_namespaces_reg()

        # step 4: generate the code for constants
        constlist = list(self.consts.items())
        constlist.sort()
        for name, constinfo in constlist:
            self.gen_const_reg(constinfo)

        # That's it. Now save all the files
        self.save(output_path, "pyopencv_generated_include.h", self.code_include)
        self.save(output_path, "pyopencv_generated_funcs.h", self.code_funcs)
        self.save(output_path, "pyopencv_generated_types.h", self.code_types)
        self.save(output_path, "pyopencv_generated_type_reg.h", self.code_type_reg)
        self.save(output_path, "pyopencv_generated_ns_reg.h", self.code_ns_reg)

if __name__ == "__main__":
    srcfiles = hdr_parser.opencv_hdr_list
    dstdir = "/Users/vp/tmp"
    if len(sys.argv) > 1:
        dstdir = sys.argv[1]
    if len(sys.argv) > 2:
        srcfiles = open(sys.argv[2], 'r').read().split(';')
    generator = PythonWrapperGenerator()
    generator.gen(srcfiles, dstdir)