#!/usr/bin/env python3
"""QR/Barcode scanner using pyzbar + OpenCV for Raspberry Pi Camera Module v3."""

import cv2
from pyzbar import pyzbar
import time


def main():
    # Camera Module v3 uses libcamera (not V4L2 by default)
    # GStreamer pipeline for libcamera
    gst_pipeline = (
        "libcamerasrc ! "
        "video/x-raw, format=NV12, width=1280, height=960 ! "
        "videoconvert ! "
        "video/x-raw, format=BGR ! "
        "appsink"
    )

    cap = cv2.VideoCapture(gst_pipeline, cv2.CAP_GSTREAMER)

    if not cap.isOpened():
        # Fallback: try V4L2 if libcamera pipeline fails
        print("GStreamer pipeline failed, trying /dev/video0...")
        cap = cv2.VideoCapture(0)
        if not cap.isOpened():
            print("Error: Cannot open camera")
            return

        cap.set(cv2.CAP_PROP_FRAME_WIDTH, 1280)
        cap.set(cv2.CAP_PROP_FRAME_HEIGHT, 960)

    scanned_codes = set()

    print("Scanner running. Press 'q' to quit, 'r' to reset scanned codes.")

    try:
        while True:
            ret, frame = cap.read()
            if not ret:
                print("Failed to grab frame")
                break

            gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
            codes = pyzbar.decode(gray)

            for code in codes:
                data = code.data.decode("utf-8")
                code_type = code.type

                if data not in scanned_codes:
                    scanned_codes.add(data)
                    print(f"[{code_type}] {data}  (total unique: {len(scanned_codes)})")

                # Draw bounding box
                points = code.polygon
                if len(points) == 4:
                    pts = [(p.x, p.y) for p in points]
                    for i in range(4):
                        cv2.line(frame, pts[i], pts[(i + 1) % 4], (0, 255, 0), 3)

                # Draw data label
                cv2.putText(
                    frame,
                    data[:40],
                    (points[0].x, points[0].y - 10),
                    cv2.FONT_HERSHEY_SIMPLEX,
                    0.5,
                    (0, 255, 0),
                    2,
                )

            cv2.imshow("Scanner", frame)

            key = cv2.waitKey(1) & 0xFF
            if key == ord("q"):
                break
            elif key == ord("r"):
                scanned_codes.clear()
                print("Scanned codes reset.")

    except KeyboardInterrupt:
        pass
    finally:
        cap.release()
        cv2.destroyAllWindows()


if __name__ == "__main__":
    main()