# -*- coding: utf-8 -*-
"""
Kontinuierliche LED-Animationen (Endlosschleife, CONTINUOUS = True).

Enthaelt Blink-, Atmen- und Puls-Animationen die endlos wiederholt werden.
"""

from __future__ import annotations

import math
from collections.abc import Iterator

from trixy_core.led.animations import IAnimation, RGB
from trixy_core.led.layouts import LEDLayout

# Schwarz / aus
OFF: RGB = (0, 0, 0)

# Schritte pro Zyklus
BREATHE_STEPS = 60
PULSE_STEPS = 30


class BlinkAnimation(IAnimation):
    """Endloses Blinken: an/aus im Wechsel.

    Bei Jewel: Center-LED bleibt bei center_color (wenn angegeben),
    Ring-LEDs blinken normal.
    """

    NAME = "blink"
    CONTINUOUS = True

    def frames(
        self,
        led_count: int,
        color: RGB,
        speed: int,
        layout: LEDLayout,
        **opts: object,
    ) -> Iterator[list[RGB]]:
        center_color: RGB | None = opts.get("center_color")  # type: ignore[assignment]

        on_frame = [color] * led_count
        if layout.center_index is not None and center_color is not None:
            on_frame[layout.center_index] = center_color

        # Aus-Frame: Center behalt center_color wenn gesetzt
        off_frame = [OFF] * led_count
        if layout.center_index is not None and center_color is not None:
            off_frame[layout.center_index] = center_color

        while True:
            yield list(on_frame)
            yield list(off_frame)


class BreatheAnimation(IAnimation):
    """Sanftes Atmen mit Sinuskurve.

    Helligkeit folgt einer Sinuswelle ueber 60 Frames pro Zyklus
    (0% → 100% → 0%). Bei Jewel: Center atmet mit halber Intensitaet.
    """

    NAME = "breathe"
    CONTINUOUS = True

    def frames(
        self,
        led_count: int,
        color: RGB,
        speed: int,
        layout: LEDLayout,
        **opts: object,
    ) -> Iterator[list[RGB]]:
        center_color: RGB | None = opts.get("center_color")  # type: ignore[assignment]

        while True:
            for step in range(BREATHE_STEPS):
                # Sinuskurve: 0 → 1 → 0 ueber einen Zyklus
                brightness = (math.sin(2 * math.pi * step / BREATHE_STEPS - math.pi / 2) + 1) / 2

                frame = [_scale_color(color, brightness)] * led_count

                # Jewel-Center: halbe Intensitaet
                if layout.center_index is not None:
                    base = center_color if center_color is not None else color
                    frame[layout.center_index] = _scale_color(base, brightness * 0.5)

                yield frame


class PulseAnimation(IAnimation):
    """Schneller Puls mit Dreieckswelle.

    Abrupter als Breathe, verwendet eine lineare Dreieckswelle
    statt einer Sinuskurve. 30 Frames pro Zyklus.
    """

    NAME = "pulse"
    CONTINUOUS = True

    def frames(
        self,
        led_count: int,
        color: RGB,
        speed: int,
        layout: LEDLayout,
        **opts: object,
    ) -> Iterator[list[RGB]]:
        center_color: RGB | None = opts.get("center_color")  # type: ignore[assignment]

        while True:
            for step in range(PULSE_STEPS):
                # Dreieckswelle: 0 → 1 (erste Haelfte), 1 → 0 (zweite Haelfte)
                half = PULSE_STEPS // 2
                if step < half:
                    brightness = step / half
                else:
                    brightness = (PULSE_STEPS - step) / half

                frame = [_scale_color(color, brightness)] * led_count

                # Jewel-Center: gleiche Dreieckswelle, halbe Intensitaet
                if layout.center_index is not None:
                    base = center_color if center_color is not None else color
                    frame[layout.center_index] = _scale_color(base, brightness * 0.5)

                yield frame


# ── Hilfsfunktionen ──────────────────────────────────────────────────────


def _scale_color(color: RGB, factor: float) -> RGB:
    """Skaliert eine RGB-Farbe um einen Faktor (0.0 - 1.0).

    Args:
        color: Ausgangsfarbe als (R, G, B).
        factor: Helligkeitsfaktor zwischen 0.0 und 1.0.

    Returns:
        Skalierte RGB-Farbe mit geclampten Werten.
    """
    return (
        min(255, max(0, int(color[0] * factor))),
        min(255, max(0, int(color[1] * factor))),
        min(255, max(0, int(color[2] * factor))),
    )


def get_animations() -> list[type[IAnimation]]:
    """Gibt alle kontinuierlichen Animationsklassen zurueck."""
    return [
        BlinkAnimation,
        BreatheAnimation,
        PulseAnimation,
    ]