import os
import cv2
import numpy as np


def detect_edges(image_path, low_threshold, high_threshold):
    """使用 Canny 算法进行边缘检测"""
    image = cv2.imread(image_path, cv2.IMREAD_GRAYSCALE)
    if image is None:
        raise ValueError(f"Failed to load image from {image_path}")

    blurred_image = cv2.GaussianBlur(image, (5, 5), 0)
    edges = cv2.Canny(blurred_image, low_threshold, high_threshold)
    return edges


def find_edge_bounds(edges):
    """找到边缘检测结果中的最远边界"""
    # 获取所有边缘点的坐标
    y_coords, x_coords = np.nonzero(edges)

    if len(x_coords) == 0 or len(y_coords) == 0:
        return None  # 如果没有检测到边缘，返回 None

    # 计算边缘点的最小和最大坐标
    min_x = np.min(x_coords)
    max_x = np.max(x_coords)
    min_y = np.min(y_coords)
    max_y = np.max(y_coords)

    return min_x, max_x, min_y, max_y


def crop_image(image, min_x, max_x, min_y, max_y):
    """从图像中截取指定区域"""
    return image[min_y:max_y, min_x:max_x]


def process_image(image_path, output_path, low_threshold, high_threshold):
    """处理单张图像，进行边缘检测并截取指定区域"""
    edges = detect_edges(image_path, low_threshold, high_threshold)
    image = cv2.imread(image_path)

    if image is None:
        raise ValueError(f"Failed to load image from {image_path}")

    bounds = find_edge_bounds(edges)
    if bounds is None:
        print(f"No edges detected in {image_path}")
        return

    min_x, max_x, min_y, max_y = bounds
    cropped_image = crop_image(image, min_x, max_x, min_y, max_y)
    cv2.imwrite(output_path, cropped_image)
    print(f"Saved cropped image to {output_path}")


def process_images_in_folder(input_folder, output_folder, low_threshold, high_threshold):
    """处理文件夹中的所有图像文件，进行边缘检测并截取指定区域"""
    if not os.path.exists(output_folder):
        os.makedirs(output_folder)

    for filename in os.listdir(input_folder):
        if filename.lower().endswith(('.png', '.jpg', '.jpeg')):
            image_path = os.path.join(input_folder, filename)
            output_path = os.path.join(output_folder, filename)
            process_image(image_path, output_path, low_threshold, high_threshold)


# 设置参数
input_folder = r'/mnt/d/slikDetect/datasets/AlreadyCheckOnlyTiaoJuan/OnlyTiaoJuanImages/'  # 输入文件夹路径
output_folder = 'edge_cut_original'  # 输出文件夹路径
low_threshold = 50  # Canny 边缘检测的低阈值
high_threshold = 150  # Canny 边缘检测的高阈值

# 处理文件夹中的所有图像
process_images_in_folder(input_folder, output_folder, low_threshold, high_threshold)