"""Default wiring for one or two WS2812 strips per board."""

from __future__ import annotations

from dataclasses import dataclass
from typing import Literal

from leds.detect import board_family, pio_available, pio_device, pi5_second_spi_bus

try:
    from leds.array_config import MATRIX_SPI_BUS, MATRIX_SPI_DEVICE
except ImportError:
    MATRIX_SPI_BUS = 0
    MATRIX_SPI_DEVICE = 0

BackendName = Literal["auto", "pio", "spi", "rpi5_ws2812", "ws281x"]


@dataclass
class StripConfig:
    count: int
    backend: BackendName = "auto"
    pin: int = 18
    channel: int = 0
    device: str = "/dev/leds0"
    spi_bus: int = 0
    spi_device: int = 0
    spi_max_speed_hz: int | None = None
    wire_order: str | None = None
    brightness: float = 1.0
    passthrough: bool = False
    swap_rg: bool = True


def panel_strip_config(
    panel_index: int,
    count: int,
    *,
    spi_max_speed_hz: int | None = None,
    wire_order: str | None = None,
    brightness: float = 1.0,
    passthrough: bool = True,
    swap_rg: bool = True,
) -> StripConfig:
    from leds.array_config import LOCAL_PANEL_INDICES, PANEL_SPI_BUS_BY_INDEX

    if panel_index in PANEL_SPI_BUS_BY_INDEX:
        spi_bus = PANEL_SPI_BUS_BY_INDEX[panel_index]
    elif panel_index in LOCAL_PANEL_INDICES:
        spi_bus = pi5_second_spi_bus()
    else:
        spi_bus = MATRIX_SPI_BUS
    return spi_strip_config(
        count,
        spi_bus=spi_bus,
        spi_device=MATRIX_SPI_DEVICE,
        spi_max_speed_hz=spi_max_speed_hz,
        wire_order=wire_order,
        brightness=brightness,
        passthrough=passthrough,
        swap_rg=swap_rg,
    )


def spi_strip_config(
    count: int,
    *,
    spi_bus: int = MATRIX_SPI_BUS,
    spi_device: int = MATRIX_SPI_DEVICE,
    spi_max_speed_hz: int | None = None,
    wire_order: str | None = None,
    brightness: float = 1.0,
    backend: BackendName | None = None,
    passthrough: bool = False,
    swap_rg: bool = True,
) -> StripConfig:
    if backend is None:
        backend = "rpi5_ws2812" if board_family() == "pi5" else "spi"
    return StripConfig(
        count,
        backend=backend,
        spi_bus=spi_bus,
        spi_device=spi_device,
        spi_max_speed_hz=spi_max_speed_hz,
        wire_order=wire_order,
        brightness=brightness,
        passthrough=passthrough,
        swap_rg=swap_rg,
    )


def default_strip_config(count: int, *, brightness: float = 1.0) -> StripConfig:
    family = board_family()
    if family == "pi5":
        if pio_available():
            return StripConfig(
                count,
                backend="pio",
                pin=18,
                device=pio_device(0) or "/dev/leds0",
                brightness=brightness,
            )
        return spi_strip_config(count, brightness=brightness)
    return StripConfig(
        count,
        backend="ws281x",
        pin=18,
        channel=0,
        brightness=brightness,
    )


def default_dual_strip_configs(
    count0: int,
    count1: int,
    *,
    brightness: float = 1.0,
) -> tuple[StripConfig, StripConfig]:
    """
    Suggested wiring for two independent strips:

    Pi 5 (SPI — requires dtoverlay=spi1-3cs under [all], not [cm5]):
      strip 0 → GPIO 10 (SPI0 MOSI), /dev/spidev0.0
      strip 1 → GPIO 20 (SPI1 MOSI), /dev/spidev1.0

    Pi 5 (ws2812-pio — alternative):
      strip 0 → GPIO 18, /dev/leds0
      strip 1 → GPIO 13, /dev/leds1

    Pi 4 / Zero:
      strip 0 → GPIO 18 (PWM channel 0)
      strip 1 → GPIO 13 (PWM channel 1)
    """
    family = board_family()
    if family == "pi5":
        if pio_available():
            return (
                StripConfig(
                    count0,
                    backend="pio",
                    pin=18,
                    device=pio_device(0) or "/dev/leds0",
                    brightness=brightness,
                ),
                StripConfig(
                    count1,
                    backend="pio",
                    pin=13,
                    device=pio_device(1) or "/dev/leds1",
                    brightness=brightness,
                ),
            )
        return (
            StripConfig(
                count0,
                backend="spi",
                spi_bus=0,
                spi_device=0,
                brightness=brightness,
            ),
            StripConfig(
                count1,
                backend="spi",
                spi_bus=pi5_second_spi_bus(),
                spi_device=0,
                brightness=brightness,
            ),
        )

    return (
        StripConfig(
            count0,
            backend="ws281x",
            pin=18,
            channel=0,
            brightness=brightness,
        ),
        StripConfig(
            count1,
            backend="ws281x",
            pin=13,
            channel=1,
            brightness=brightness,
        ),
    )


def pi5_setup_hint(count0: int, count1: int) -> str:
    return (
        "Pi 5 second SPI bus not found. Add under [all] in /boot/firmware/config.txt:\n"
        "  dtparam=spi=on\n"
        "  dtoverlay=spi1-3cs\n"
        "Remove dtparam=spi1=on (ignored on Pi 5). Do not put the overlay under [cm5]\n"
        "unless you have a Compute Module 5.\n"
        "Wire strip 0 DIN → GPIO 10, strip 1 DIN → GPIO 20, then reboot."
    )