"""UCD 控制 Domain 层。

纯数据 + 纯函数：枚举、值对象、状态机、错误体系、事件总线、
业务字符串解析与映射。本模块**不**依赖 UniTAP / 任何硬件；
可用纯单测覆盖。

文件分区：
    §1 枚举与值对象
    §2 状态机
    §3 错误体系
    §4 事件总线
    §5 业务字符串解析 / 映射
"""

from __future__ import annotations

import logging
from dataclasses import dataclass, field
from enum import Enum
from typing import Any, Callable

log = logging.getLogger(__name__)


# ─── §1 枚举与值对象 ──────────────────────────────────────────────


class Interface(str, Enum):
    """UCD 物理输出接口。"""

    HDMI = "HDMI"
    DP = "DP"
    USBC = "Type-C"


class ColorFormat(str, Enum):
    """像素颜色格式（与 UI 显示字符串解耦的内部表示）。"""

    RGB = "rgb"
    YCBCR_444 = "ycbcr444"
    YCBCR_422 = "ycbcr422"
    YCBCR_420 = "ycbcr420"
    Y_ONLY = "yonly"
    IDO_DEFINED = "ido_defined"
    RAW = "raw"
    DSC = "dsc"


class Colorimetry(str, Enum):
    """色度空间。"""

    SRGB = "sRGB"
    BT709 = "BT.709"
    BT601 = "BT.601"
    BT2020 = "BT.2020"
    DCI_P3 = "DCI-P3"
    ADOBE_RGB = "AdobeRGB"


class DynamicRange(str, Enum):
    FULL = "Full"
    LIMITED = "Limited"


class TimingStandard(str, Enum):
    DMT = "dmt"
    CTA = "cta"
    CVT = "cvt"
    OVT = "ovt"


class PatternKind(str, Enum):
    """高层图案种类。

    与 UCD 内部 VideoPattern 枚举区分：仅暴露业务上真正用到的几种。
    """

    DISABLED = "disabled"
    SOLID = "solidcolor"
    SOLID_WHITE = "solidwhite"
    SOLID_RED = "solidred"
    SOLID_GREEN = "solidgreen"
    SOLID_BLUE = "solidblue"
    COLOR_BARS = "colorbars"
    CHESSBOARD = "chessboard"
    WHITE_VSTRIPS = "whitevstrips"
    GRADIENT_RGB_STRIPES = "gradientrgbstripes"
    COLOR_RAMP = "colorramp"
    COLOR_SQUARES = "coloursquares"
    MOTION = "motionpattern"
    SQUARE_WINDOW = "squarewindow"
    IMAGE = "image"  # 来自文件路径


@dataclass(frozen=True)
class SignalFormat:
    """信号格式（color_info 部分）。"""

    color_format: ColorFormat
    colorimetry: Colorimetry
    bpc: int  # 8 / 10 / 12
    dynamic_range: DynamicRange = DynamicRange.FULL


@dataclass(frozen=True)
class TimingSpec:
    """显示 Timing 描述。"""

    standard: TimingStandard
    width: int
    height: int
    refresh_hz: float

    def __str__(self) -> str:  # 便于日志
        return f"{self.standard.value.upper()} {self.width}x{self.height}@{self.refresh_hz:g}Hz"


@dataclass(frozen=True)
class PatternSpec:
    """图案描述。

    联合字段含义：
        SOLID         → solid_rgb=(r,g,b)
        IMAGE         → image_path
        其它预定义图案 → extras 视具体类型
    """

    kind: PatternKind
    solid_rgb: tuple[int, int, int] | None = None
    image_path: str | None = None
    extras: tuple = field(default_factory=tuple)


# ─── §2 状态机 ───────────────────────────────────────────────────


class UcdState(Enum):
    CLOSED = 0
    OPENED = 1  # 设备已打开，未配置信号
    CONFIGURED = 2  # SignalFormat + Timing 已写入，未 apply
    APPLIED = 3  # 已 apply，硬件正在输出


_ALLOWED: dict[UcdState, set[UcdState]] = {
    UcdState.CLOSED: {UcdState.OPENED, UcdState.CLOSED},
    UcdState.OPENED: {UcdState.CONFIGURED, UcdState.CLOSED, UcdState.OPENED},
    UcdState.CONFIGURED: {UcdState.CONFIGURED, UcdState.APPLIED, UcdState.OPENED, UcdState.CLOSED},
    UcdState.APPLIED: {UcdState.CONFIGURED, UcdState.APPLIED, UcdState.OPENED, UcdState.CLOSED},
}


def assert_transition(curr: UcdState, nxt: UcdState) -> None:
    """校验状态转移。非法转移抛 :class:`UcdStateError`。"""
    if nxt not in _ALLOWED[curr]:
        raise UcdStateError(f"非法状态转移: {curr.name} -> {nxt.name}")


# ─── §3 错误体系 ─────────────────────────────────────────────────


class UcdError(Exception):
    """UCD 控制相关错误的基类。"""


class UcdNotConnected(UcdError):
    """设备未打开/未连接。"""


class UcdStateError(UcdError):
    """状态机非法转移或前置条件不满足。"""


class UcdConfigError(UcdError):
    """业务配置参数不合法（如不支持的 color_format、解析失败）。"""


class UcdApplyFailed(UcdError):
    """SDK ``apply`` 返回失败或超时。"""


class UcdSdkError(UcdError):
    """UniTAP SDK 内部异常的包装；原始异常保存在 ``__cause__``。"""


# ─── §4 事件总线 ─────────────────────────────────────────────────


@dataclass(frozen=True)
class UcdEvent:
    """事件基类。"""


@dataclass(frozen=True)
class ConnectionChanged(UcdEvent):
    connected: bool
    serial: str | None = None


@dataclass(frozen=True)
class SignalApplied(UcdEvent):
    signal: SignalFormat
    timing: TimingSpec
    format_changed: bool  # 与上一次 apply 相比 (signal,timing) 是否改变


@dataclass(frozen=True)
class PatternApplied(UcdEvent):
    pattern: PatternSpec


class EventBus:
    """极简同步事件总线（按事件类型分发）。

    单线程使用；如需跨线程派发，由订阅者自行 marshal 到 UI 线程。
    """

    def __init__(self) -> None:
        self._subs: dict[type, list[Callable[[Any], None]]] = {}

    def subscribe(self, evt_type: type, cb: Callable[[Any], None]) -> None:
        self._subs.setdefault(evt_type, []).append(cb)

    def publish(self, evt: UcdEvent) -> None:
        for cb in self._subs.get(type(evt), []):
            try:
                cb(evt)
            except Exception:  # noqa: BLE001 - 订阅者错误不应影响发布者
                log.exception("UCD 事件处理器抛出异常: %r", evt)


# ─── §5 业务字符串解析 / 映射 ────────────────────────────────────


_OUTPUT_FORMAT_TO_COLOR_FORMAT: dict[str, ColorFormat] = {
    "RGB": ColorFormat.RGB,
    "YCbCr 4:4:4": ColorFormat.YCBCR_444,
    "YCbCr 4:2:2": ColorFormat.YCBCR_422,
    "YCbCr 4:2:0": ColorFormat.YCBCR_420,
    "Y Only": ColorFormat.Y_ONLY,
    "IDO Defined": ColorFormat.IDO_DEFINED,
    "RAW": ColorFormat.RAW,
    "DSC": ColorFormat.DSC,
}

_COLOR_SPACE_TO_COLORIMETRY: dict[str, Colorimetry] = {
    "sRGB": Colorimetry.SRGB,
    "BT.709": Colorimetry.BT709,
    "BT.601": Colorimetry.BT601,
    "BT.2020": Colorimetry.BT2020,
    "DCI-P3": Colorimetry.DCI_P3,
    "AdobeRGB": Colorimetry.ADOBE_RGB,
}

_BIT_DEPTH_STR_TO_BPC: dict[str, int] = {
    "8bit": 8,
    "10bit": 10,
    "12bit": 12,
}

_DATA_RANGE_TO_DYNAMIC_RANGE: dict[str, DynamicRange] = {
    "Full": DynamicRange.FULL,
    "Limited": DynamicRange.LIMITED,
}


def output_format_to_color_format(s: str) -> ColorFormat:
    """显示用 ``"YCbCr 4:4:4"`` → :class:`ColorFormat`。未知值视为 RGB。"""
    return _OUTPUT_FORMAT_TO_COLOR_FORMAT.get(s, ColorFormat.RGB)


def color_space_to_colorimetry(s: str) -> Colorimetry:
    """显示用 ``"BT.709"`` → :class:`Colorimetry`。未知抛 :class:`UcdConfigError`。"""
    if s in _COLOR_SPACE_TO_COLORIMETRY:
        return _COLOR_SPACE_TO_COLORIMETRY[s]
    raise UcdConfigError(f"未知色彩空间: {s!r}")


def bit_depth_str_to_bpc(s: str) -> int:
    """``"10bit"`` → 10。未知抛 :class:`UcdConfigError`。"""
    if s in _BIT_DEPTH_STR_TO_BPC:
        return _BIT_DEPTH_STR_TO_BPC[s]
    raise UcdConfigError(f"未知位深: {s!r}")


def data_range_to_dynamic_range(s: str) -> DynamicRange:
    if s in _DATA_RANGE_TO_DYNAMIC_RANGE:
        return _DATA_RANGE_TO_DYNAMIC_RANGE[s]
    raise UcdConfigError(f"未知数据范围: {s!r}")


def is_ycbcr(color_format: ColorFormat | str | None) -> bool:
    """判断输出是否为 YCbCr 系列。接受 :class:`ColorFormat` 或 UI 字符串。"""
    if color_format is None:
        return False
    if isinstance(color_format, ColorFormat):
        return color_format in {
            ColorFormat.YCBCR_444,
            ColorFormat.YCBCR_422,
            ColorFormat.YCBCR_420,
        }
    return "YCbCr" in str(color_format)


def parse_timing_str(timing_str: str) -> TimingSpec:
    """解析 ``"DMT 3840x2160@60Hz"`` 风格的字符串为 :class:`TimingSpec`。

    宽容处理空格 / 大小写 / ``Hz`` 后缀大小写。
    解析失败抛 :class:`UcdConfigError`。
    """
    if not isinstance(timing_str, str):
        raise UcdConfigError(f"timing_str 必须是字符串: {timing_str!r}")

    s = " ".join(timing_str.strip().split())
    s = s.replace(" x", "x").replace("x ", "x")

    parts = s.split(" ", 1)
    if len(parts) < 2:
        raise UcdConfigError(f"无法解析 timing: {timing_str!r}")
    type_str, rest = parts[0].strip().upper(), parts[1].strip()

    if "@" not in rest:
        raise UcdConfigError(f"无法解析 timing (缺少 '@'): {timing_str!r}")
    left, right = (p.strip() for p in rest.split("@", 1))

    if "x" not in left:
        raise UcdConfigError(f"无法解析分辨率 (缺少 'x'): {timing_str!r}")
    wh = left.split("x")
    if len(wh) != 2:
        raise UcdConfigError(f"无法解析分辨率: {timing_str!r}")
    try:
        width, height = int(wh[0]), int(wh[1])
    except ValueError as exc:
        raise UcdConfigError(f"分辨率数字解析失败: {timing_str!r}") from exc

    hz_str = right.replace("Hz", "").replace("HZ", "").strip()
    try:
        refresh_hz = float(hz_str)
    except ValueError as exc:
        raise UcdConfigError(f"刷新率解析失败: {timing_str!r}") from exc

    try:
        standard = TimingStandard(type_str.lower())
    except ValueError as exc:
        raise UcdConfigError(f"未知的分辨率类型: {type_str!r}") from exc

    return TimingSpec(
        standard=standard,
        width=width,
        height=height,
        refresh_hz=refresh_hz,
    )


__all__ = [
    # §1
    "Interface",
    "ColorFormat",
    "Colorimetry",
    "DynamicRange",
    "TimingStandard",
    "PatternKind",
    "SignalFormat",
    "TimingSpec",
    "PatternSpec",
    # §2
    "UcdState",
    "assert_transition",
    # §3
    "UcdError",
    "UcdNotConnected",
    "UcdStateError",
    "UcdConfigError",
    "UcdApplyFailed",
    "UcdSdkError",
    # §4
    "UcdEvent",
    "ConnectionChanged",
    "SignalApplied",
    "PatternApplied",
    "EventBus",
    # §5
    "output_format_to_color_format",
    "color_space_to_colorimetry",
    "bit_depth_str_to_bpc",
    "data_range_to_dynamic_range",
    "is_ycbcr",
    "parse_timing_str",
]