import cv2
import time
import os
import numpy as np
from PIL import Image
from skimage.metrics import structural_similarity as ssim
import shutil

# ================== 配置参数 ==================
rtsp_url = "rtsp://192.168.144.25:8554/main.264"  # RTSP 流地址
capture_interval = 1.0  # 每隔多少秒采集一次（单位：秒）
SSIM_THRESHOLD = 0.9  # SSIM 相似度阈值，>0.9 认为太像
output_dir = os.path.join("userdata", "image")  # 图片保存路径

# 灰色判断参数
GRAY_LOWER = 70
GRAY_UPPER = 230
GRAY_RATIO_THRESHOLD = 0.7

# 创建输出目录
if not os.path.exists(output_dir):
    os.makedirs(output_dir)
    print(f"已创建目录: {output_dir}")

def is_large_gray(image, gray_lower=GRAY_LOWER, gray_upper=GRAY_UPPER, ratio_thresh=GRAY_RATIO_THRESHOLD):
    """
    判断图片是否大面积为灰色（R/G/B 都在 [gray_lower, gray_upper] 区间）
    """
    img_array = np.array(image)
    if len(img_array.shape) != 3 or img_array.shape[2] != 3:
        return True  # 非三通道图视为无效/灰色

    h, w, _ = img_array.shape
    total = h * w

    gray_mask = (
            (img_array[:, :, 0] >= gray_lower) & (img_array[:, :, 0] <= gray_upper) &
            (img_array[:, :, 1] >= gray_lower) & (img_array[:, :, 1] <= gray_upper) &
            (img_array[:, :, 2] >= gray_lower) & (img_array[:, :, 2] <= gray_upper)
    )
    gray_pixels = np.sum(gray_mask)
    gray_ratio = gray_pixels / total

    return gray_ratio > ratio_thresh

max_retry_seconds = 10  # 最大重试时间为10秒
retry_interval_seconds = 1  # 每隔1秒尝试重新连接一次

last_gray = None  # 用于 SSIM 去重

while True:  # 外层循环用于处理重新连接逻辑
    cap = cv2.VideoCapture(rtsp_url)
    start_time = time.time()  # 记录开始尝试连接的时间

    while not cap.isOpened():
        if time.time() - start_time >= max_retry_seconds:
            print(f"已尝试重新连接 {max_retry_seconds} 秒，但仍无法获取视频流。")
            exit()

        print("无法打开摄像头，正在尝试重新连接...")
        time.sleep(retry_interval_seconds)
        cap = cv2.VideoCapture(rtsp_url)

    print("✅ 开始读取视频流...")

    last_capture_time = time.time()
    frame_count = 0

    try:
        while True:
            ret, frame = cap.read()
            if not ret:
                print("读取帧失败，可能是流中断或摄像头断开")
                cap.release()
                break

            current_time = time.time()
            if current_time - last_capture_time < capture_interval:
                continue

            frame_count += 1
            last_capture_time = current_time

            print(f"处理帧 {frame_count}")

            rgb_frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
            pil_image = Image.fromarray(rgb_frame)

            if is_large_gray(pil_image):
                print(f"跳过：大面积灰色图像 (frame_{frame_count})")
                continue

            gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
            if last_gray is not None:
                similarity = ssim(gray, last_gray)
                if similarity > SSIM_THRESHOLD:
                    print(f"跳过：与上一帧太相似 (SSIM={similarity:.3f})")
                    continue

            last_gray = gray.copy()

            timestamp = time.strftime("%Y%m%d_%H%M%S")
            ms = int((time.time() % 1) * 1000)
            filename = f"frame_{timestamp}_{ms:03d}.png"
            filepath = os.path.join(output_dir, filename)

            total, used, free = shutil.disk_usage(output_dir)
            if free < 1024 * 1024 * 20:  # 小于 20MB 就停止
                print(f"❌ 磁盘空间严重不足（仅剩 {free / (1024**3):.2f} GB），停止运行。")
                raise SystemExit(1)

            try:
                pil_image.save(filepath, format='PNG')
                print(f"已保存: {filepath}")
            except (OSError, IOError) as e:
                error_msg = str(e)
                if "No space left on device" in error_msg or "disk full" in error_msg.lower() or "quota" in error_msg.lower():
                    print(f"磁盘空间不足，无法保存 {filepath}！错误: {e}")
                    print("停止程序以防止无限错误。")
                    raise SystemExit(1)
                else:
                    print(f"保存失败 {filename}: {e}（非磁盘空间问题，继续运行）")

            cv2.imshow('Camera Stream (Live)', frame)
            if cv2.waitKey(1) & 0xFF == ord('q'):
                raise KeyboardInterrupt

    except KeyboardInterrupt:
        print("\n用户中断")
        break

    finally:
        cap.release()
        cv2.destroyAllWindows()
        print(f"视频流已关闭，共处理 {frame_count} 帧。")

print("程序结束")