import math
import time
from machine import Pin
import neopixel

class BoardLED:
    """Utility class to control the onboard WS2812 (NeoPixel) RGB LED on GPIO 38."""
    
    def __init__(self, pin_num=38):
        self.np = neopixel.NeoPixel(Pin(pin_num), 1)
        self.base_color = (0, 0, 0)
        self.off()

    def set_color(self, r, g, b):
        """Sets the RGB LED to a specific static color.
        
        Values are between 0 and 255.
        """
        self.base_color = (r, g, b)
        self.np[0] = (r, g, b)
        self.np.write()

    def off(self):
        """Turns the RGB LED off."""
        self.set_color(0, 0, 0)

    def update_breathing(self, speed_factor=1.0):
        """Performs one step of a non-blocking breathing animation.
        
        Call this regularly in the main application loop.
        
        Args:
            speed_factor (float): Speeds up or slows down the breathing rate.
        """
        if self.base_color == (0, 0, 0):
            return
            
        t = time.ticks_ms() / 1000.0 * speed_factor
        # Sine wave from 0.05 to 1.0 for breathing intensity
        factor = 0.525 + 0.475 * math.sin(t * math.pi)
        
        br = int(self.base_color[0] * factor)
        bg = int(self.base_color[1] * factor)
        bb = int(self.base_color[2] * factor)
        
        self.np[0] = (br, bg, bb)
        self.np.write()
        
    def update_rainbow(self, speed_factor=0.2):
        """Performs one step of a non-blocking rainbow color cycle.
        
        Call this regularly in the main application loop.
        """
        t = time.ticks_ms() / 1000.0 * speed_factor
        # Use phase offsets of 120 degrees (2pi/3) for red, green, blue
        r = int(127.5 * (1.0 + math.sin(t * 2.0 * math.pi)))
        g = int(127.5 * (1.0 + math.sin(t * 2.0 * math.pi + 2.0 * math.pi / 3.0)))
        b = int(127.5 * (1.0 + math.sin(t * 2.0 * math.pi + 4.0 * math.pi / 3.0)))
        
        self.np[0] = (r, g, b)
        self.np.write()