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

@description
Emboss / relief effect. Creates a 3D raised appearance by highlighting
edges from a simulated light direction. Great for sculptural looks.

@param strength float
  @range 0.5 3
  @default 1.0
  Emboss intensity.

@param direction float
  @range 0 360
  @default 135
  Light direction in degrees. Bind to beat for rotating light.

@param blend float
  @range 0 1
  @default 0.3
  Blend with original (0 = full emboss, 1 = original).

@example
  (effect emboss :strength 1.5)

@example
  ;; Rotating light direction
  (effect emboss :direction (bind beat_position :range [0 360]))
"""

import numpy as np
import cv2


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

    Args:
        frame: Input frame as numpy array (H, W, 3) RGB uint8
        params: Effect parameters
            - strength: emboss intensity (default 1.0)
            - direction: light angle in degrees (default 135)
            - blend: mix with original (default 0.3)
        state: Persistent state dict (unused)

    Returns:
        Tuple of (processed_frame, new_state)
    """
    strength = params.get("strength", 1.0)
    direction = params.get("direction", 135)
    blend = params.get("blend", 0.3)

    # Calculate kernel based on direction
    angle_rad = np.deg2rad(direction)
    dx = np.cos(angle_rad)
    dy = np.sin(angle_rad)

    # Create emboss kernel
    kernel = np.array([
        [-strength * dy - strength * dx, -strength * dy, -strength * dy + strength * dx],
        [-strength * dx, 1, strength * dx],
        [strength * dy - strength * dx, strength * dy, strength * dy + strength * dx]
    ], dtype=np.float32)

    # Apply to grayscale
    gray = cv2.cvtColor(frame, cv2.COLOR_RGB2GRAY).astype(np.float32)
    embossed = cv2.filter2D(gray, -1, kernel)

    # Normalize
    embossed = embossed + 128
    embossed = np.clip(embossed, 0, 255)

    # Convert to RGB
    embossed_rgb = cv2.cvtColor(embossed.astype(np.uint8), cv2.COLOR_GRAY2RGB)

    # Blend with original
    if blend > 0:
        result = frame.astype(np.float32) * blend + embossed_rgb.astype(np.float32) * (1 - blend)
        return np.clip(result, 0, 255).astype(np.uint8), state

    return embossed_rgb, state