from __future__ import annotations

from dataclasses import dataclass
from typing import Literal, TypeAlias


@dataclass(frozen=True)
class MemoryWriteMsg:
    correlation_id: str
    request_id: str
    dst_sip: int
    dst_cube: int
    dst_pe: int
    dst_pa: int
    nbytes: int
    src_kind: Literal["pattern", "host_buffer_ref"] = "pattern"
    pattern: str | None = None
    target_cubes: tuple[int, ...] | Literal["all"] = "all"
    target_pe: int | Literal["all"] = "all"
    msg_type: Literal["memory_write"] = "memory_write"


@dataclass(frozen=True)
class MemoryReadMsg:
    correlation_id: str
    request_id: str
    src_sip: int
    src_cube: int
    src_pe: int
    src_pa: int
    nbytes: int
    target_cubes: tuple[int, ...] | Literal["all"] = "all"
    target_pe: int | Literal["all"] = "all"
    msg_type: Literal["memory_read"] = "memory_read"


@dataclass(frozen=True)
class KernelRef:
    """Reference to a kernel binary or builtin timing model.

    Kernel binaries must be pre-deployed to device memory via MemoryWriteMsg.
    KernelLaunchMsg references the deployed location by PA — source code or IR
    MUST NOT be embedded in launch messages.

    - "deployed": kernel binary pre-deployed to HBM/SRAM at deploy_pa.
    - "builtin":  simulator built-in timing model, identified by name.
    """

    name: str
    kind: Literal["deployed", "builtin"]
    deploy_pa: int | None = None
    deploy_sip: int = 0
    deploy_cube: int = 0
    deploy_pe: int = 0
    nbytes_code: int = 0


@dataclass(frozen=True)
class TensorArgShard:
    sip: int
    cube: int
    pe: int
    pa: int
    nbytes: int
    offset_bytes: int


@dataclass(frozen=True)
class TensorArg:
    shards: tuple[TensorArgShard, ...]
    arg_kind: Literal["tensor"] = "tensor"


@dataclass(frozen=True)
class ScalarArg:
    dtype: str
    value: float | int
    arg_kind: Literal["scalar"] = "scalar"


KernelArg: TypeAlias = TensorArg | ScalarArg


@dataclass(frozen=True)
class KernelLaunchMsg:
    correlation_id: str
    request_id: str
    kernel_ref: KernelRef
    args: tuple[KernelArg, ...]
    target_cubes: tuple[int, ...] | Literal["all"] = "all"
    target_pe: int | Literal["all"] = "all"
    msg_type: Literal["kernel_launch"] = "kernel_launch"


@dataclass(frozen=True)
class ResponseMsg:
    """Device→Host response carrying PE execution result."""

    correlation_id: str
    request_id: str
    src_cube: int
    src_pe: int
    success: bool
    msg_type: Literal["response"] = "response"


@dataclass(frozen=True)
class PeDmaMsg:
    """Direct PE DMA request: host injects a transfer at PE_DMA level.

    Used by the probe utility to measure PE→HBM latency without requiring
    the full PE_CPU → scheduler → DMA pipeline.
    """

    correlation_id: str
    request_id: str
    src_sip: int
    src_cube: int
    src_pe: int
    dst_pa: int
    nbytes: int
    is_write: bool = False
    msg_type: Literal["pe_dma"] = "pe_dma"