# Generated by pypy/tool/import_cffi.py
import pytest, sys
try:
    # comment out the following line to run this test.
    # the latest on x86-64 linux: https://github.com/libffi/libffi/issues/574
    if sys.platform != 'win32':
        raise ImportError("this test is skipped because it keeps finding "
                          "failures in libffi, instead of cffi")

    from hypothesis import given, settings, example
    from hypothesis import strategies as st
except ImportError as e:
    e1 = e
    def test_types():
        pytest.skip(str(e1))
else:

    from cffi import FFI
    import sys, random
    from .test_recompiler import verify

    ALL_PRIMITIVES = [
        'unsigned char',
        'short',
        'int',
        'long',
        'long long',
        'float',
        'double',
        #'long double',   --- on x86 it can give libffi crashes
    ]
    def _make_struct(s):
        return st.lists(s, min_size=1)
    types = st.one_of(st.sampled_from(ALL_PRIMITIVES),
                      st.lists(st.sampled_from(ALL_PRIMITIVES), min_size=1))
    # NB. 'types' could be st.recursive instead, but it doesn't
    # really seem useful

    def draw_primitive(ffi, typename):
        value = random.random() * 2**40
        if typename != 'long double':
            return ffi.cast(typename, value)
        else:
            return value

    TEST_RUN_COUNTER = 0


    @given(st.lists(types), types)
    @settings(max_examples=100, deadline=5000)   # 5000ms
    def test_types(tp_args, tp_result):
        global TEST_RUN_COUNTER
        print(tp_args, tp_result)
        cdefs = []
        structs = {}

        def build_type(tp):
            if type(tp) is list:
                field_types = [build_type(tp1) for tp1 in tp]
                fields = ['%s f%d;' % (ftp, j)
                          for (j, ftp) in enumerate(field_types)]
                fields = '\n    '.join(fields)
                name = 's%d' % len(cdefs)
                cdefs.append("typedef struct {\n    %s\n} %s;" % (fields, name))
                structs[name] = field_types
                return name
            else:
                return tp

        args = [build_type(tp) for tp in tp_args]
        result = build_type(tp_result)

        TEST_RUN_COUNTER += 1
        signature = "%s testfargs(%s)" % (result,
            ', '.join(['%s a%d' % (arg, i) for (i, arg) in enumerate(args)])
            or 'void')

        source = list(cdefs)

        cdefs.append("%s;" % signature)
        cdefs.append("extern %s testfargs_result;" % result)
        for i, arg in enumerate(args):
            cdefs.append("extern %s testfargs_arg%d;" % (arg, i))
        source.append("%s testfargs_result;" % result)
        for i, arg in enumerate(args):
            source.append("%s testfargs_arg%d;" % (arg, i))
        source.append(signature)
        source.append("{")
        for i, arg in enumerate(args):
            source.append("    testfargs_arg%d = a%d;" % (i, i))
        source.append("    return testfargs_result;")
        source.append("}")

        typedef_line = "typedef %s;" % (signature.replace('testfargs',
                                                          '(*mycallback_t)'),)
        assert signature.endswith(')')
        sig_callback = "%s testfcallback(mycallback_t callback)" % result
        cdefs.append(typedef_line)
        cdefs.append("%s;" % sig_callback)
        source.append(typedef_line)
        source.append(sig_callback)
        source.append("{")
        source.append("    return callback(%s);" %
                ', '.join(["testfargs_arg%d" % i for i in range(len(args))]))
        source.append("}")

        ffi = FFI()
        ffi.cdef("\n".join(cdefs))
        lib = verify(ffi, 'test_function_args_%d' % TEST_RUN_COUNTER,
                     "\n".join(source), no_cpp=True)

        # when getting segfaults, enable this:
        if False:
            from extra_tests.cffi_tests.udir import udir
            import subprocess
            f = open(str(udir.join('run1.py')), 'w')
            f.write('import sys; sys.path = %r\n' % (sys.path,))
            f.write('from _CFFI_test_function_args_%d import ffi, lib\n' %
                    TEST_RUN_COUNTER)
            for i in range(len(args)):
                f.write('a%d = ffi.new("%s *")\n' % (i, args[i]))
            aliststr = ', '.join(['a%d[0]' % i for i in range(len(args))])
            f.write('lib.testfargs(%s)\n' % aliststr)
            f.write('ffi.addressof(lib, "testfargs")(%s)\n' % aliststr)
            f.close()
            print("checking for segfault for direct call...")
            rc = subprocess.call([sys.executable, 'run1.py'], cwd=str(udir))
            assert rc == 0, rc

        def make_arg(tp):
            if tp in structs:
                return [make_arg(tp1) for tp1 in structs[tp]]
            else:
                return draw_primitive(ffi, tp)

        passed_args = [make_arg(arg) for arg in args]
        returned_value = make_arg(result)

        def write(p, v):
            if type(v) is list:
                for i, v1 in enumerate(v):
                    write(ffi.addressof(p, 'f%d' % i), v1)
            else:
                p[0] = v

        write(ffi.addressof(lib, 'testfargs_result'), returned_value)

        ## CALL forcing libffi
        print("CALL forcing libffi")
        received_return = ffi.addressof(lib, 'testfargs')(*passed_args)
        ##

        _tp_long_double = ffi.typeof("long double")
        def check(p, v):
            if type(v) is list:
                for i, v1 in enumerate(v):
                    check(ffi.addressof(p, 'f%d' % i), v1)
            else:
                if ffi.typeof(p).item is _tp_long_double:
                    assert ffi.cast("double", p[0]) == v
                else:
                    assert p[0] == v

        for i, arg in enumerate(passed_args):
            check(ffi.addressof(lib, 'testfargs_arg%d' % i), arg)
        ret = ffi.new(result + "*", received_return)
        check(ret, returned_value)

        ## CALLBACK
        def expand(value):
            if isinstance(value, ffi.CData):
                t = ffi.typeof(value)
                if t is _tp_long_double:
                    return float(ffi.cast("double", value))
                return [expand(getattr(value, 'f%d' % i))
                        for i in range(len(t.fields))]
            else:
                return value

        # when getting segfaults, enable this:
        if False:
            from extra_tests.cffi_tests.udir import udir
            import subprocess
            f = open(str(udir.join('run1.py')), 'w')
            f.write('import sys; sys.path = %r\n' % (sys.path,))
            f.write('from _CFFI_test_function_args_%d import ffi, lib\n' %
                    TEST_RUN_COUNTER)
            f.write('def callback(*args): return ffi.new("%s *")[0]\n' % result)
            f.write('fptr = ffi.callback("%s(%s)", callback)\n' % (result,
                                                                ','.join(args)))
            f.write('print(lib.testfcallback(fptr))\n')
            f.close()
            print("checking for segfault for callback...")
            rc = subprocess.call([sys.executable, 'run1.py'], cwd=str(udir))
            assert rc == 0, rc

        seen_args = []
        def callback(*args):
            seen_args.append([expand(arg) for arg in args])
            return returned_value

        fptr = ffi.callback("%s(%s)" % (result, ','.join(args)), callback)
        print("CALL with callback")
        received_return = lib.testfcallback(fptr)

        assert len(seen_args) == 1
        assert passed_args == seen_args[0]
        ret = ffi.new(result + "*", received_return)
        check(ret, returned_value)
