# Owner(s): ["module: unknown"]

from functools import partial
from textwrap import dedent

import torch

from torch.testing import FileCheck
from torch.testing._internal.common_utils import \
    (run_tests, IS_SANDCASTLE, clone_input_helper, first_sample, skipIfSlowGradcheckEnv)
from torch.testing._internal.common_methods_invocations import op_db
from torch.testing._internal.common_device_type import instantiate_device_type_tests, ops, OpDTypes
from torch.testing._internal.common_jit import JitCommonTestCase, check_against_reference
from torch.testing._internal.jit_metaprogramming_utils import create_script_fn, create_traced_fn, check_alias_annotation
from torch.testing._internal.jit_utils import disable_autodiff_subgraph_inlining, is_lambda


# TODO: fixme https://github.com/pytorch/pytorch/issues/68972
torch.set_default_dtype(torch.float32)

# variant testing is only done with torch.float and torch.cfloat to avoid
#   excessive test times and maximize signal to noise ratio
_variant_ops = partial(ops, dtypes=OpDTypes.supported,
                       allowed_dtypes=(torch.float, torch.cfloat))


# Tests operators for consistency between JIT and eager, also checks
#   correctness of JIT specific alias schemas and intended
#   autodifferentiation behavior.
# Inherits from JitCommonTestCase instead of TestCase directly to share
#   functionality with original test_jit.py method operator tests
@skipIfSlowGradcheckEnv
class TestJit(JitCommonTestCase):
    exact_dtype = True

    # Tests that the forward and backward passes of operations produce the
    #   same values for the cross-product of op variants (function, method, inplace)
    #   and runtimes (eager, traced, scripted).
    # TODO WARNING: inplace x {traced, scripted} not currently tested
    @_variant_ops(op_db)
    def test_variant_consistency_jit(self, device, dtype, op):
        _requires_grad = (dtype in op.supported_backward_dtypes(torch.device(device).type))

        include_conjugated_inputs = op.test_conjugated_samples and dtype.is_complex
        samples = op.sample_inputs(device, dtype, requires_grad=_requires_grad, include_conjugated_inputs=include_conjugated_inputs)

        # Acquires variants to test
        func = op.get_op()
        method = op.get_method()
        variants = {
            # TODO: inplace tests currently fail, fix and add inplace variant
            'function': func, 'method': method,
        }

        # scripting strips the torch.ops prefix from these operators
        # incorrectly; don't bother testing this case.  Count this
        # as "testing"
        if isinstance(func, torch._ops.OpOverload):
            self.skipTest("variant consistency doesn't work on torch.ops")

        # TODO: find better way to standardize on op registration itself..
        has_fake_function = op.name in ["resize_", 'resize_as_']

        if has_fake_function:
            variants = {'method': getattr(torch.Tensor, op.name)}
            samples = op.sample_inputs(device, dtype, requires_grad=False)


        tested = False
        for sample in samples:
            # Test traced and scripted consistency
            for func_type, variant in variants.items():
                if variant is None:
                    continue

                # scripting and check_alias_analysis do not work with lambdas
                # lambdas are typically used as a way to simulate methods without
                # functional variants, so rely on the other variant for testing
                # for now
                if is_lambda(variant):
                    continue

                tested = True
                try:
                    self.indiv_variant_test_jit(device, dtype, op, sample, func_type, variant, has_fake_function)
                except Exception as e:
                    variant_error_info = dedent(f"""
                        Error testing {op.name} {func_type} variant
                        with dtype: {dtype}
                        with inputs {sample}:
                    """)
                    raise Exception(variant_error_info) from e

        assert tested, "JIT Test does not execute any logic"

    def indiv_variant_test_jit(self, device, dtype, op, sample, func_type, variant, has_fake_function):
        _requires_grad = (dtype in op.supported_backward_dtypes(torch.device(device).type))
        support_script = op.supports_scripting
        # Create accessor for script function variant
        name = op.name + '_' if func_type == 'inplace' else op.name

        # run with disable_autodiff_subgraph_inlining(True) to test
        #   autodiff support. Context manager forces the graph to contain
        #   DifferentiableGraph nodes if they are present
        with disable_autodiff_subgraph_inlining():
            # Check scripted forward, grad, and grad grad
            if support_script:
                script_fn = create_script_fn(self, name, func_type)

            def out_fn(output):
                # Processes the output for autograd
                if sample.output_process_fn_grad is not None:
                    return sample.output_process_fn_grad(output)
                return output

            def get_sample():
                return clone_input_helper(sample.input) if op.name[-1] == '_' else sample.input

            if support_script:
                check_against_reference(self,
                                        script_fn,
                                        op.get_op(),
                                        out_fn,
                                        (get_sample(),) + sample.args,
                                        sample.kwargs,
                                        no_grad=not _requires_grad, no_gradgrad=not op.supports_gradgrad)

            # Check traced forward, grad, and grad grad
            # TODO: fix tracing here
            supports_tracing = op.supports_tracing and not has_fake_function
            if op.assert_jit_shape_analysis:
                self.assertTrue(supports_tracing)

            if supports_tracing:
                traced_fn = create_traced_fn(self, variant)
                check_against_reference(self,
                                        traced_fn,
                                        op.get_op(),
                                        out_fn,
                                        (get_sample(),) + sample.args,
                                        sample.kwargs,
                                        no_grad=not _requires_grad, no_gradgrad=not op.supports_gradgrad)

            # Check alias annotation schema for correctness (make
            #   sure inputs that aren't supposed to be modified aren't)
            # Note: only runs in float32 because schema isn't affected by dtype,
            #   so running it on all dtypes is would be excessive
            if dtype == torch.float32:
                # TODO: no reason why we cant run this with tracing graph
                if support_script and op.name != "rsub":
                    check_alias_annotation(name, (get_sample(),) + sample.args, sample.kwargs,
                                           func_type=func_type, aten_name=op.aten_name)

                # TODO: use script graph as well
                checked_shape_analysis = False
                if supports_tracing:
                    out = variant(get_sample(), *sample.args, **sample.kwargs)

                    # right now, tuple of outputs and tensor output supported
                    # TODO: list of tensor outputs
                    tuple_of_tensors = isinstance(out, tuple) and all([isinstance(elem, torch.Tensor) for elem in out])

                    if isinstance(out, torch.Tensor) or tuple_of_tensors:
                        if tuple_of_tensors:
                            sizes = [elem.size() for elem in out]
                        else:
                            sizes = out.size()
                        self.checkShapeAnalysis(sizes, traced_fn.graph, op.assert_jit_shape_analysis)
                        checked_shape_analysis = True
                if op.assert_jit_shape_analysis:
                    self.assertTrue(checked_shape_analysis)

            # Check autodifferentiation of nodes for traced and scripted graphs, only need to check once per sample
            if dtype is torch.float32:
                # Sandcastle doesn't fuse nodes
                if IS_SANDCASTLE:
                    # fusible nodes are expected to be found in FusionGroups in the DifferentiableGraphs
                    nonfusible_nodes = op.autodiff_nonfusible_nodes + op.autodiff_fusible_nodes
                    fusible_nodes = []
                else:
                    nonfusible_nodes = op.autodiff_nonfusible_nodes
                    fusible_nodes = op.autodiff_fusible_nodes

                if supports_tracing:
                    self.assertAutodiffNode(traced_fn.last_graph, op.assert_autodiffed, nonfusible_nodes, fusible_nodes)
                if support_script:
                    self.assertAutodiffNode(script_fn.last_graph, op.assert_autodiffed, nonfusible_nodes, fusible_nodes)

    # alias testing is only done with torch.float for the same reason
    _alias_ops = partial(ops, dtypes=OpDTypes.supported,
                         allowed_dtypes=(torch.float,))

    @_alias_ops((op for op in op_db if op.aliases))
    def test_jit_alias_remapping(self, device, dtype, op):
        # NOTE: only tests on first sample
        samples = op.sample_inputs(device, dtype, requires_grad=True)
        sample = first_sample(self, samples)

        # [Scripting Data Preparation]
        # Prepare data for test scripting
        # Below we prepare strings of args/kwargs with and without type annotations.
        # These strings are inserted into function template strings which is then torch scripted.
        # - args string is ["t0"] corresponding to the "input" tensor required by the op
        # - args_kw is the value of args and strings of kwargs used to call the op (without type annotations), for example,
        # ["to", "1.0", "(1,)", "True", "tensor(1.0)"] -> def fn(t0): return variant(t0, 1.0, (1,), True, tensor(1.0))
        args = ["t0"]

        def quote_strs(v):
            if isinstance(v, str):
                return f"'{v}'"

            return str(v)

        args_kw = args + \
            [f"{v}" for v in sample.args] + \
            [f"{k}={quote_strs(v)}" for k, v in sample.kwargs.items()]

        # Prepare data for test tracing
        sample_args_kwargs = ()
        if len(sample.args) > 0:
            sample_args_kwargs += (sample.args, )
        if len(sample.kwargs) > 0:
            sample_args_kwargs += (sample.kwargs, )

        original_name = op.aten_name
        original_name_inplace = original_name + "_"
        expected_dtype = op(sample.input, *sample.args, **sample.kwargs).dtype

        for a_op in op.aliases:
            inplace = a_op.inplace_variant
            method_or_inplace = [a_op.inplace_variant, a_op.method_variant]
            variants = (v for v in (a_op.op, a_op.method_variant, a_op.inplace_variant) if v is not None)

            # Test scripting:
            for variant in variants:
                variant_name = variant.__name__
                op_name = original_name_inplace if variant is inplace else original_name

                if variant in method_or_inplace:
                    fn_template = '''
                        def _fn(t0{c}):
                            return t0.{alias_name}({args_kw})
                    '''
                    # remove the first input tensor
                    script = fn_template.format(
                        c=", " if len(args_kw[1:]) > 1 else "",
                        args_kw=", ".join(args_kw[1:]),
                        alias_name=variant_name,
                    )
                else:
                    fn_template = '''
                        def _fn({args}):
                            return variant({args_kw})
                    '''
                    script = fn_template.format(
                        args=", ".join(args),
                        args_kw=", ".join(args_kw),
                    )

                # Required to avoid undefined value: tensor error in JIT
                # compilation of the function template
                script = script.replace("tensor(", "torch.tensor(")

                scripted = torch.jit.CompilationUnit(script)._fn

                if (variant is inplace and not torch.can_cast(expected_dtype, dtype)):
                    try:
                        inp = clone_input_helper(sample.input)
                        scripted(inp)
                    except Exception as e:
                        continue
                    self.fail("Inplace operation on integer tensor that should be promoted to float didn't fail!")

                inp = clone_input_helper(sample.input)
                scripted(inp)
                inp = clone_input_helper(sample.input)
                graph = scripted.graph_for(inp)
                FileCheck().check(op.aten_name).check_not(variant_name).run(graph)

            # Test tracing:
            for variant in variants:
                variant_name = variant.__name__
                op_name = original_name_inplace if variant is inplace else original_name

                def _fn(*sample_args, **sample_kwargs):
                    return variant(*sample_args, **sample_kwargs)

                inp = (clone_input_helper(sample.input),) + sample_args_kwargs
                traced = torch.jit.trace(_fn, *inp)
                inp = (clone_input_helper(sample.input),) + sample_args_kwargs
                traced(*inp)
                inp = (clone_input_helper(sample.input),) + sample_args_kwargs
                graph = traced.graph_for(*inp)
                FileCheck().check(op_name).check_not(variant_name).run(graph)


instantiate_device_type_tests(TestJit, globals())

if __name__ == '__main__':
    run_tests()