import numpy as np
import cv2


class QrCodeDetector:
    def __init__(self) -> None:
        self.detector = cv2.QRCodeDetector()
        self.detector.setUseAlignmentMarkers(True) 

    def __call__(self, img: np.ndarray) -> tuple[bool, list[str], np.ndarray]:
        found_code, code_strings, corners, _ = self.detector.detectAndDecodeMulti(img)
        
        return (found_code, code_strings, corners)
    

def draw_rectangle(img: np.ndarray, corner_points: np.ndarray):
    corner_points = corner_points.astype(np.int32)[np.newaxis]
    return cv2.polylines(img, corner_points, True, (0, 255, 0), 3)

def draw_text(img: np.ndarray, top_left_corner: np.ndarray, text: str):
    return cv2.putText(img, text, top_left_corner.astype(int), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 0, 255), 2, cv2.LINE_AA)


if __name__ == "__main__":
    FILENAME = "example.png"
    WND = "QR"
    
    detector = QrCodeDetector()
    img = cv2.imread(FILENAME)
    img = cv2.resize(img, None, fx=0.3, fy=0.3)
    #img = cv2.flip(img, 1)
    
    valid, codes, corners = detector(img)
    
    if valid:
        for code, corner in zip(codes, corners):
            img = draw_rectangle(img, corner)
            img = draw_text(img, corner[0], code) 
    
    print(codes)
    
    cv2.imshow(WND, img)
    cv2.waitKey(0)