# mypy: allow-untyped-defs
from typing import Sequence, Union

from ..scheduler import (
    BaseSchedulerNode,
    BaseScheduling,
    FusedSchedulerNode,
    Scheduler,
    SchedulerNode,
)
from .cuda.cuda_cpp_scheduling import CUDACPPScheduling

from .triton import TritonScheduling


class CUDACombinedScheduling(BaseScheduling):
    """
    Scheduler for CUDA Kernels, which delegates calls as appropriate
    to the CUDA-C++ and Triton Schedulers, which both work for CUDA devices
    and use a unified-wrapper for codegen.

    If Scheduling code needs to be specialized for the case of mixed Triton / CUDA C++ code,
    this would also be the place to do it.
    """

    def __init__(self, scheduler: Scheduler):
        super().__init__()
        self._scheduler = scheduler
        self._triton_scheduling = TritonScheduling(scheduler)
        self._cuda_cpp_scheduling = CUDACPPScheduling(scheduler)

    def choose_node_backend(self, node: BaseSchedulerNode) -> BaseScheduling:
        if self._cuda_cpp_scheduling.is_cuda_cpp_template(node):
            return self._cuda_cpp_scheduling
        return self._triton_scheduling

    def can_fuse_vertical(self, node1: BaseSchedulerNode, node2: BaseSchedulerNode):
        if self._cuda_cpp_scheduling.can_fuse_vertical(node1, node2):
            return True
        return self._triton_scheduling.can_fuse_vertical(node1, node2)

    def can_fuse_horizontal(self, node1: BaseSchedulerNode, node2: BaseSchedulerNode):
        for node in (node1, node2):
            if self._cuda_cpp_scheduling.is_cuda_cpp_template(node):
                return self._cuda_cpp_scheduling.can_fuse_horizontal(
                    node1, node2
                )  # always False at the moment
        return self._triton_scheduling.can_fuse_horizontal(node1, node2)

    def group_fn(self, sizes):
        return self._triton_scheduling.group_fn(sizes)

    def codegen_template(
        self,
        template_node: BaseSchedulerNode,
        epilogue_nodes: Sequence[BaseSchedulerNode],
    ):
        if self._cuda_cpp_scheduling.is_cuda_cpp_template(template_node):
            assert epilogue_nodes is None or len(epilogue_nodes) == 0
            return self._cuda_cpp_scheduling.codegen_template(
                template_node, epilogue_nodes
            )
        else:
            return self._triton_scheduling.codegen_template(
                template_node, epilogue_nodes
            )

    def codegen_node(self, node: Union[FusedSchedulerNode, SchedulerNode]):
        return self._triton_scheduling.codegen_node(node)

    def codegen_sync(self):
        return self._triton_scheduling.codegen_sync()

    def flush(self):
        return self._triton_scheduling.flush()

    def codegen_foreach(self, *args, **kwargs):
        return self._triton_scheduling.codegen_foreach(*args, **kwargs)

    def benchmark_fused_nodes(self, nodes):
        return self._triton_scheduling.benchmark_fused_nodes(nodes)

    def generate_kernel_code_from_nodes(self, nodes, benchmark_kernel=False):
        return self._triton_scheduling.generate_kernel_code_from_nodes(
            nodes, benchmark_kernel
        )