import json
from typing import List, Optional
from .student_dal import IStudentDAL
from ..model.student import Student
from datetime import datetime


class JsonStudentDAL(IStudentDAL):
    """学生信息的JSON文件存储实现"""

    def __init__(self, file_path: str = 'students.json'):
        self.file_path = file_path
        self._ensure_file_exists()

    def _ensure_file_exists(self):
        """确保JSON文件存在"""
        try:
            with open(self.file_path, 'r', encoding='utf-8') as file:
                json.load(file)
        except (FileNotFoundError, json.JSONDecodeError):
            with open(self.file_path, 'w', encoding='utf-8') as file:
                json.dump([], file)

    def _student_to_dict(self, student: Student) -> dict:
        """将Student对象转换为字典"""
        return {
            'name': student.name,
            'id_card': student.id_card,
            'stu_id': student.stu_id,
            'gender': student.gender,
            'height': student.height,
            'weight': student.weight,
            'enrollment_date': str(student.enrollment_date) if student.enrollment_date else None,
            'class_name': student.class_name,
            'major': student.major,
            'email': student.email,
            'phone': student.phone
        }

    def _dict_to_student(self, data: dict) -> Student:
        """将字典转换为Student对象"""
        # 处理日期类型
        enrollment_date = data.get('enrollment_date')
        if enrollment_date:
            enrollment_date = datetime.strptime(enrollment_date, '%Y-%m-%d').date()

        return Student(
            name=data.get('name'),
            id_card=data.get('id_card'),
            stu_id=data.get('stu_id'),
            gender=data.get('gender'),
            height=data.get('height'),
            weight=data.get('weight'),
            enrollment_date=enrollment_date,
            class_name=data.get('class_name'),
            major=data.get('major'),
            email=data.get('email'),
            phone=data.get('phone')
        )

    def _load_data(self) -> List[dict]:
        """加载JSON文件数据"""
        with open(self.file_path, 'r', encoding='utf-8') as file:
            return json.load(file)

    def _save_data(self, data: List[dict]):
        """保存数据到JSON文件"""
        with open(self.file_path, 'w', encoding='utf-8') as file:
            json.dump(data, file, ensure_ascii=False, indent=2)

    def get_by_id(self, id_card: str) -> Optional[Student]:
        """根据身份证号获取学生信息"""
        for data in self._load_data():
            if data.get('id_card') == id_card:
                return self._dict_to_student(data)
        return None

    def get_by_stu_id(self, stu_id: str) -> Optional[Student]:
        """根据学号获取学生信息"""
        for data in self._load_data():
            if data.get('stu_id') == stu_id:
                return self._dict_to_student(data)
        return None

    def get_all(self) -> List[Student]:
        """获取所有学生信息"""
        return [self._dict_to_student(data) for data in self._load_data()]

    def add(self, student: Student) -> bool:
        """添加学生信息"""
        # 检查学号和身份证号是否已存在
        if self.get_by_id(student.id_card) or self.get_by_stu_id(student.stu_id):
            return False

        data = self._load_data()
        data.append(self._student_to_dict(student))
        self._save_data(data)
        return True

    def update(self, student: Student) -> bool:
        """更新学生信息"""
        data = self._load_data()
        updated = False

        for i, item in enumerate(data):
            if item.get('id_card') == student.id_card:
                data[i] = self._student_to_dict(student)
                updated = True
                break

        if updated:
            self._save_data(data)
        return updated

    def delete_by_id(self, id_card: str) -> bool:
        """根据身份证号删除学生信息"""
        data = self._load_data()
        original_length = len(data)

        data = [item for item in data if item.get('id_card') != id_card]

        if len(data) < original_length:
            self._save_data(data)
            return True
        return False

    def delete_by_stu_id(self, stu_id: str) -> bool:
        """根据学号删除学生信息"""
        data = self._load_data()
        original_length = len(data)

        data = [item for item in data if item.get('stu_id') != stu_id]

        if len(data) < original_length:
            self._save_data(data)
            return True
        return False

    def search_by_name(self, name: str) -> List[Student]:
        """根据姓名模糊查询学生信息"""
        return [self._dict_to_student(data) for data in self._load_data() if name in data.get('name', '')]

    def search_by_class(self, class_name: str) -> List[Student]:
        """根据班级模糊查询学生信息"""
        return [self._dict_to_student(data) for data in self._load_data() if
                class_name in (data.get('class_name') or '')]

    def search_by_major(self, major: str) -> List[Student]:
        """根据专业模糊查询学生信息"""
        return [self._dict_to_student(data) for data in self._load_data() if major in (data.get('major') or '')]