import ctypes
hello_lib = ctypes.CDLL('./hello.so') #/windows

# 1. Square (int -> int)
hello_lib.square.argtypes = [ctypes.c_int]
hello_lib.square.restype = ctypes.c_int

x = 4
result = hello_lib.square(x)
print(f'the square of {x} is {result}')

hello_lib.sum_elements.argtypes = [ctypes.POINTER(ctypes.c_int), ctypes.c_int]
hello_lib.sum_elements.restype = ctypes.c_int

# 2. Sum (int*, int -> int)
N = 4
p = [3, 1, 2, 4]
# Converts Python list to C array. (*p) is equivalent to (3, 1, 2, 4)
c_array = (ctypes.c_int * len(p))(*p)
# Get the address of the array
p_pointer = ctypes.cast(c_array, ctypes.POINTER(ctypes.c_int))

result = hello_lib.sum_elements(p_pointer, N) # pass in p_pointer or c_array both works
print(f"the sum of the array is {result}")

import numpy as np
from numpy.ctypeslib import ndpointer

# 3. Sort (in place float*)
hello_lib.bubble_sort.argtypes = [ndpointer(dtype=np.float32, flags='C_CONTIGUOUS'), ctypes.c_int]
hello_lib.bubble_sort.restype = None
arr = np.array([3.0, 2.3, 4.2, 1.9, 3.2, 1.7], dtype=np.float32)
hello_lib.bubble_sort(arr, len(arr))
print(arr)

# 4. Create (int, float -> float*)
a = 0.523
N = 6
hello_lib.generate_sine_values.argtypes = [ctypes.c_float, ctypes.c_int]
hello_lib.generate_sine_values.restype = ndpointer(dtype=np.float32, shape=(N,))
result_arr = hello_lib.generate_sine_values(a, N)
print(type(result_arr))
print(result_arr)