from flask import Flask, request, jsonify
import cv2
import dlib
import numpy as np
from scipy.spatial import distance

app = Flask(__name__)

# 加载 Dlib 的人脸检测器和关键点检测器
detector = dlib.get_frontal_face_detector()
predictor = dlib.shape_predictor("shape_predictor_68_face_landmarks.dat")

def get_face_landmarks(image):
    """
    获取图像中的人脸轮廓关键点
    """
    gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    faces = detector(gray)
    if len(faces) == 0:
        return None
    # 只处理第一张人脸
    face = faces[0]
    landmarks = predictor(gray, face)
    return np.array([[p.x, p.y] for p in landmarks.parts()])

def compare_contours(contour1, contour2):
    """
    比较两个轮廓的相似度，返回偏移评估值
    """
    if contour1 is None or contour2 is None:
        return None
    # 计算两个轮廓之间的欧氏距离
    dist = distance.cdist(contour1, contour2, 'euclidean')
    # 返回平均偏移值
    return np.mean(dist)

@app.route('/upload', methods=['POST'])
def upload_image():
    """
    处理前端上传的照片，计算轮廓偏移值
    """
    if 'file' not in request.files:
        return jsonify({"error": "No file uploaded"}), 400

    file = request.files['file']
    if file.filename == '':
        return jsonify({"error": "No file selected"}), 400

    # 读取上传的图像
    image = cv2.imdecode(np.frombuffer(file.read(), np.uint8), cv2.IMREAD_COLOR)
    if image is None:
        return jsonify({"error": "Failed to read image"}), 400

    # 获取上传图像的人脸轮廓
    uploaded_contour = get_face_landmarks(image)
    if uploaded_contour is None:
        return jsonify({"error": "No face detected in uploaded image"}), 400

    # 读取标准图像
    standard_image = cv2.imread("standard_face.jpg")
    if standard_image is None:
        return jsonify({"error": "Failed to read standard image"}), 400

    # 获取标准图像的人脸轮廓
    standard_contour = get_face_landmarks(standard_image)
    if standard_contour is None:
        return jsonify({"error": "No face detected in standard image"}), 400

    # 比较两个轮廓
    offset_value = compare_contours(uploaded_contour, standard_contour)
    if offset_value is None:
        return jsonify({"error": "Failed to compare contours"}), 400

    # 返回偏移评估值
    return jsonify({"offset_value": float(offset_value)}), 200

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)