import os
import json
import numpy as np
import face_recognition
import piexif
from datetime import datetime
from werkzeug.utils import secure_filename
from PIL import Image
from models import db, User, Photo

# 目录路径
UPLOAD_FOLDER = 'static/uploads'
USER_FOLDER = os.path.join(UPLOAD_FOLDER, 'users')
PHOTO_FOLDER = os.path.join(UPLOAD_FOLDER, 'photos')
TEMP_FOLDER = os.path.join(UPLOAD_FOLDER, 'temp')

# 确保目录存在
for folder in [USER_FOLDER, PHOTO_FOLDER, TEMP_FOLDER]:
    os.makedirs(folder, exist_ok=True)


def extract_face_encoding(photo_path):
    """提取人脸编码"""
    image = face_recognition.load_image_file(photo_path)
    encodings = face_recognition.face_encodings(image)
    return encodings[0] if encodings else None


def save_with_exif(image_path, save_path):
    """保存图片并保留 EXIF 信息"""
    image = Image.open(image_path)
    exif_data = image.getexif()
    if exif_data:
        exif_bytes = piexif.dump(dict(exif_data))
        image.save(save_path, exif=exif_bytes)
    else:
        image.save(save_path)
    return exif_data


def format_exif_date(exif_data):
    """格式化 EXIF 时间为 YYYY-MM-DD"""
    try:
        return datetime.strptime(exif_data[306], "%Y:%m:%d %H:%M:%S").strftime("%Y-%m-%d")
    except (KeyError, ValueError, TypeError):
        return None  # 处理无效时间


def add_user(username, userphoto):
    """添加用户并提取人脸编码"""
    if not username or not userphoto:
        return False

    user_dir = os.path.join(USER_FOLDER, username)
    os.makedirs(user_dir, exist_ok=True)

    photo_path = os.path.join(user_dir, "photo.jpg")
    userphoto.save(photo_path)

    encoding = extract_face_encoding(photo_path)
    if encoding is None:
        return False

    new_user = User(username=username, encoding=json.dumps(encoding.tolist()), photo=photo_path)
    db.session.add(new_user)
    db.session.commit()
    return True


def edit_user(user_id, new_name, new_photo):
    """编辑用户信息"""
    user = User.query.get(user_id)
    if not user:
        return False

    user.username = new_name

    if new_photo:
        user_dir = os.path.join(USER_FOLDER, new_name)
        os.makedirs(user_dir, exist_ok=True)

        photo_path = os.path.join(user_dir, secure_filename(new_photo.filename))
        new_photo.save(photo_path)

        encoding = extract_face_encoding(photo_path)
        if encoding:
            user.encoding = json.dumps(encoding.tolist())
            user.photo = photo_path

    db.session.commit()
    return True



import shutil

def delete_user(user_id):
    """删除用户及其所有相关文件"""
    user = User.query.get(user_id)
    if not user:
        return False

    user_folder = os.path.join("static", "uploads", "users", user.username)
    user_folder = user_folder.replace("\\", "/")

    # 删除整个用户文件夹及其内容
    if os.path.exists(user_folder):
        shutil.rmtree(user_folder)

    db.session.delete(user)
    db.session.commit()
    return True



def match_face(photo_path, threshold=0.30):
    """匹配数据库中的人脸，一旦找到合适的直接返回"""
    known_users = User.query.all()
    if not known_users:
        return None

    unknown_encoding = extract_face_encoding(photo_path)
    if unknown_encoding is None:
        return None

    for user in known_users:
        if not user.encoding:
            continue

        try:
            stored_encoding = np.array(json.loads(user.encoding))
            if stored_encoding.size == 0 or stored_encoding.ndim != 1:
                continue
        except (json.JSONDecodeError, TypeError):
            continue  # 解析失败，跳过

        if np.linalg.norm(stored_encoding - unknown_encoding) < threshold:
            return user  # 直接返回匹配的用户

    return None


def classify_photos(photos):
    """分类照片"""
    for photo in photos:
        filename = secure_filename(photo.filename)
        temp_photo_path = os.path.join(TEMP_FOLDER, filename)
        temp_photo_path = temp_photo_path.replace("\\", "/")

        exif_data = save_with_exif(photo, temp_photo_path)
        date_str = format_exif_date(exif_data)
        if not date_str:
            os.remove(temp_photo_path)  # 无效时间的照片直接删除
            continue

        matched_user = match_face(temp_photo_path)
        if matched_user:
            user_folder = os.path.join(USER_FOLDER, matched_user.username, date_str)
            os.makedirs(user_folder, exist_ok=True)

            classified_photo_path = os.path.join(user_folder, filename)
            classified_photo_path =classified_photo_path.replace("\\", "/")
            os.rename(temp_photo_path, classified_photo_path)

            new_photo = Photo(
                user_id=matched_user.id,
                created_at=date_str,
                classification=True,
                classification_image_path=classified_photo_path
            )
            db.session.add(new_photo)
        else:
            os.remove(temp_photo_path)  # 没匹配到的照片删除

    db.session.commit()


def search_photos(username, date):
    """搜索用户的照片"""
    user = User.query.filter_by(username=username).first()
    if not user:
        return []

    query = Photo.query.filter_by(user_id=user.id)
    if date:
        query = query.filter(Photo.created_at.like(f"{date}%"))

    return query.all()