def build_model():
    from retinaface import RetinaFace  # this is not a must dependency

    face_detector = RetinaFace.build_model()
    return face_detector


def detect_face(face_detector, img, align=True):

    from retinaface import RetinaFace  # this is not a must dependency
    from retinaface.commons import postprocess

    # ---------------------------------

    resp = []

    # --------------------------

    obj = RetinaFace.detect_faces(img, model=face_detector, threshold=0.9)

    if isinstance(obj, dict):
        for face_idx in obj.keys():
            identity = obj[face_idx]
            facial_area = identity["facial_area"]

            y = facial_area[1]
            h = facial_area[3] - y
            x = facial_area[0]
            w = facial_area[2] - x
            img_region = [x, y, w, h]
            confidence = identity["score"]

            # detected_face = img[int(y):int(y+h), int(x):int(x+w)] #opencv
            detected_face = img[facial_area[1] : facial_area[3], facial_area[0] : facial_area[2]]

            if align:
                landmarks = identity["landmarks"]
                left_eye = landmarks["left_eye"]
                right_eye = landmarks["right_eye"]
                nose = landmarks["nose"]
                # mouth_right = landmarks["mouth_right"]
                # mouth_left = landmarks["mouth_left"]

                detected_face = postprocess.alignment_procedure(
                    detected_face, right_eye, left_eye, nose
                )

            resp.append((detected_face, img_region, confidence))

    return resp