# bicubic.py

# bicubic.py

def bicubic_interpolation_rgb(c0, c1, c2, c3):
    # Initialize the result as a 5x5 gradient of RGB colors
    result = [[(0, 0, 0)] * 5 for _ in range(5)]

    for j in range(5):
        for i in range(5):
            rgb = []
            for channel in range(3):  # Loop through the RGB channels (0: Red, 1: Green, 2: Blue)
                # Calculate the bicubic interpolation for each channel
                pixel_value = bicubic(
                    c0[channel],
                    c1[channel],
                    c2[channel],
                    c3[channel],
                    i, j
                )
                rgb.append(pixel_value)
            # Store the interpolated value as an RGB tuple in the result
            result[j][i] = tuple(rgb)

    return result  # Return the 5x5 gradient of RGB colors

# Bicubic interpolation function
def bicubic(c0, c1, c2, c3, x, y):
    # Implement bicubic interpolation here
    a = c0 + (c1 - c0) * (0.5 * x)
    b = c0 + (c2 - c0) * (0.5 * y)
    c = (a + b) / 2
    d = (c + (c3 - c) * (0.5 * ((x + y) / 4)))
    z = (max(4, x + y) - 4)
    pixel_value = int(d * 2 if z else c)
    return pixel_value

# Example usage:
c0 = (0, 255, 255)
c1 = (0, 0, 255)
c2 = (255, 255, 0)
c3 = (0, 0, 0)

# Perform bicubic interpolation for the 5x5 gradient of RGB colors
interpolated_gradient = bicubic_interpolation_rgb(c0, c1, c2, c3)

# Print the interpolated gradient
for row in interpolated_gradient:
    print(row)