# /// script
# requires-python = ">=3.10"
# dependencies = ["numpy", "opencv-python"]
# ///
"""
@effect color_cycle
@version 1.0.0
@author artdag

@description
Color cycle effect. Shifts all hues over time creating psychedelic
rainbow cycling. Great for trippy visuals.

@param speed float
  @range 0 10
  @default 1
  Cycle speed (rotations per second).

@param offset float
  @range 0 360
  @default 0
  Initial hue offset in degrees.

@param saturation_boost float
  @range 0 2
  @default 1
  Saturation multiplier.

@param mode string
  @enum all highlights shadows midtones
  @default all
  Which tones to affect.

@example
  (effect color_cycle :speed 0.5)

@example
  ;; Beat-synced color shift
  (effect color_cycle :offset (bind beat_position :range [0 360]))
"""

import numpy as np
import cv2


def process_frame(frame: np.ndarray, params: dict, state: dict) -> tuple:
    """
    Apply color cycle effect to a video frame.

    Args:
        frame: Input frame as numpy array (H, W, 3) RGB uint8
        params: Effect parameters
            - speed: rotations per second (default 1)
            - offset: initial hue offset (default 0)
            - saturation_boost: saturation multiplier (default 1)
            - mode: which tones to affect (default all)
        state: Persistent state dict

    Returns:
        Tuple of (processed_frame, new_state)
    """
    speed = params.get("speed", 1)
    offset = params.get("offset", 0)
    saturation_boost = max(0, min(params.get("saturation_boost", 1), 2))
    mode = params.get("mode", "all")
    t = params.get("_time", 0)

    if state is None:
        state = {}

    # Calculate hue shift
    hue_shift = int((offset + speed * t * 360) % 360)

    # Convert to HSV (OpenCV uses BGR, our frame is RGB)
    frame_bgr = cv2.cvtColor(frame, cv2.COLOR_RGB2BGR)
    hsv = cv2.cvtColor(frame_bgr, cv2.COLOR_BGR2HSV).astype(np.float32)

    if mode == "all":
        # Shift all hues
        hsv[:, :, 0] = (hsv[:, :, 0] + hue_shift / 2) % 180
        hsv[:, :, 1] = np.clip(hsv[:, :, 1] * saturation_boost, 0, 255)
    else:
        # Calculate luminance mask
        lum = hsv[:, :, 2] / 255.0

        if mode == "highlights":
            mask = np.clip((lum - 0.67) * 3, 0, 1)
        elif mode == "shadows":
            mask = np.clip(1 - lum * 3, 0, 1)
        else:  # midtones
            shadow_mask = np.clip(1 - lum * 3, 0, 1)
            highlight_mask = np.clip((lum - 0.67) * 3, 0, 1)
            mask = 1 - shadow_mask - highlight_mask

        # Apply selective hue shift
        shifted_hue = (hsv[:, :, 0] + hue_shift / 2) % 180
        hsv[:, :, 0] = hsv[:, :, 0] * (1 - mask) + shifted_hue * mask

    # Convert back
    hsv = np.clip(hsv, 0, 255).astype(np.uint8)
    result_bgr = cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR)
    result = cv2.cvtColor(result_bgr, cv2.COLOR_BGR2RGB)

    return result, state