import json
import os, sys,csv
from datetime import date
from typing import List, Optional
from model.Student import Student

import csv
current_dir = os.path.dirname(os.path.abspath(__file__))
parent_dir = os.path.dirname(current_dir)
sys.path.append(parent_dir)
from model.Student import Student


class StudentDALJSON:
    def __init__(self, file_path="students.json"):
        self.file_path = file_path

    def get_all_students(self):
        try:
            with open(self.file_path, 'r', encoding='utf-8') as file:
                student_dicts = json.load(file)
                return [Student.from_dict(s) for s in student_dicts]
        except (FileNotFoundError, json.JSONDecodeError):
            return []

    def save_students(self, students):
        student_dicts = [student.to_dict() for student in students]
        with open(self.file_path, 'w', encoding='utf-8') as file:
            json.dump(student_dicts, file, ensure_ascii=False, indent=4)

    # 新增：导出为JSON
    def export_to_json(self, file_path=None):
        if not file_path:
            file_path = self.file_path
        students = self.get_all_students()
        if not students:
            print("没有数据可导出")
            return
        try:
            with open(file_path, 'w', encoding='utf-8') as f:
                json.dump([s.to_dict() for s in students], f, ensure_ascii=False, indent=4)
            print(f"数据已导出到 {file_path}")
        except Exception as e:
            print(f"导出失败: {e}")

    # 新增：导出为CSV
    def export_to_csv(self, file_path="students.csv"):
        students = self.get_all_students()
        if not students:
            print("没有数据可导出")
            return
        try:
            with open(file_path, 'w', encoding='utf-8-sig', newline='') as f:
                writer = csv.DictWriter(
                    f,
                    fieldnames=[
                        'student_id', 'name', 'gender', 'age', 'class_name',
                        'major', 'phone', 'email', 'id_number',
                        'height', 'weight', 'birth_date', 'enrollment_date'
                    ]
                )
                writer.writeheader()
                for student in students:
                    data = student.to_dict()
                    # 将日期对象转换为字符串
                    data['birth_date'] = data['birth_date'].isoformat()
                    data['enrollment_date'] = data['enrollment_date'].isoformat()
                    writer.writerow(data)
            print(f"数据已导出到 {file_path}")
        except Exception as e:
            print(f"导出失败: {e}")

    # 新增：从JSON导入
    def import_from_json(self, file_path):
        try:
            with open(file_path, 'r', encoding='utf-8') as f:
                student_dicts = json.load(f)
            students = []
            for data in student_dicts:
                # 转换日期字符串为日期对象
                data['birth_date'] = date.fromisoformat(data['birth_date'])
                data['enrollment_date'] = date.fromisoformat(data['enrollment_date'])
                students.append(Student.from_dict(data))
            self.save_students(students)
            print(f"从 {file_path} 导入成功")
        except FileNotFoundError:
            print(f"文件不存在: {file_path}")
        except json.JSONDecodeError:
            print(f"JSON格式错误: {file_path}")
        except Exception as e:
            print(f"导入失败: {e}")

    # 新增：从CSV导入
    def import_from_csv(self, file_path):
        try:
            with open(file_path, 'r', encoding='utf-8-sig') as f:
                reader = csv.DictReader(f)
                student_dicts = list(reader)
            students = []
            for data in student_dicts:
                # 转换数值类型
                data['age'] = int(data['age'])
                data['height'] = float(data['height'])
                data['weight'] = float(data['weight'])
                # 转换日期类型
                data['birth_date'] = date.fromisoformat(data['birth_date'])
                data['enrollment_date'] = date.fromisoformat(data['enrollment_date'])
                students.append(Student.from_dict(data))
            self.save_students(students)
            print(f"从 {file_path} 导入成功")
        except FileNotFoundError:
            print(f"文件不存在: {file_path}")
        except Exception as e:
            print(f"导入失败: {e}")
class StudentDAL:
    def __init__(self, file_path: str):
        self.file_path = file_path
        self._ensure_file_exists()

    def _ensure_file_exists(self):
        if not os.path.exists(self.file_path):
            with open(self.file_path, mode='w', encoding='utf-8') as file:
                json.dump([], file)

    def save_students(self, students: List[Student]) -> None:
        student_dicts = [student.to_dict() for student in students]
        with open(self.file_path, mode='w', encoding='utf-8') as file:
            json.dump(student_dicts, file, ensure_ascii=False, indent=4)

    def load_students(self) -> List[Student]:
        with open(self.file_path, mode='r', encoding='utf-8') as file:
            student_dicts = json.load(file)
            return [Student.from_dict(student_dict) for student_dict in student_dicts]

    def add_student(self, student: Student) -> bool:
        students = self.load_students()
        for existing_student in students:
            if existing_student.sid == student.sid:
                return False
        students.append(student)
        self.save_students(students)
        return True

    def find_student_by_sid(self, sid: str) -> Optional[Student]:
        students = self.load_students()
        for student in students:
            if student.sid == sid:
                return student
        return None

    def find_students_by_name(self, name: str) ->List[Student]:
        students = self.load_students()
        return [student for student in students if name.lower() in student.name.lower()]

    def find_students_by_class_name(self, class_name: str) ->List[Student]:
        students = self.load_students()
        return [s for s in students if class_name.lower() in s.class_name.lower()]

    def get_all_students(self) -> List[Student]:
        return self.load_students()

    def update_student(self, sid: str, updated_student: Student) -> bool:
        students = self.load_students()
        for i, student in enumerate(students):
            if student.sid == sid:
                students[i] = updated_student
                self.save_students(students)
                return True
        return False

    def update_student_partial(self, sid:str, name:Optional[str]=None, height:Optional[float]=None, birth_date:Optional[date]=None, enrollment_date:Optional[date]=None, class_name:Optional[str]=None) ->bool:
        students = self.load_students()
        for i, student in enumerate(students):
            if student.sid == sid:
                if name is not None:
                    students[i].name = name
                if height is not None:
                    students[i].height = height
                if birth_date is not None:
                    students[i].birth_date = birth_date
                if enrollment_date is not None:
                    students[i].enrollment_date = enrollment_date
                if class_name is not None:
                    students[i].class_name = class_name
                self.save_students(students)
                return True
        return False

    def delete_student(self, sid: str) -> bool:
        """根据学生 ID 删除学生"""
        students = self.load_students()
        initial_length = len(students)
        students = [student for student in students if student.sid != sid]
        if len(students) < initial_length:
            self.save_students(students)
            return True
        return False

    def clear_all_students(self) -> None:
        self.save_students([])

    def get_student_count(self) -> int:
        return len(self.load_students())

    def check_student_exists(self, sid: str) ->bool:
        return self.find_student_by_sid(sid) is not None

    def export_to_json(self, file_path):
        students = self.load_students()
        student_dicts = [student.to_dict() for student in students]
        with open(file_path, mode='w', encoding='utf-8') as file:
            json.dump(student_dicts, file, ensure_ascii=False, indent=4)

    def import_from_json(self, file_path):
        try:
            with open(file_path, mode='r', encoding='utf-8') as file:
                student_dicts = json.load(file)
                students = [Student.from_dict(student_dict) for student_dict in student_dicts]
                self.save_students(students)
        except FileNotFoundError:
            print(f"文件 {file_path} 未找到。")
        except json.JSONDecodeError:
            print(f"文件 {file_path} 不是有效的 JSON 文件。")
        except ValueError as e:
            print(f"数据转换错误: {e}")

    def export_to_csv(self, file_path):
        students = self.load_students()
        with open(file_path, mode='w', encoding='utf-8', newline='') as file:
            fieldnames = ['sid', 'name', 'height', 'birth_date', 'enrollment_date', 'class_name']
            writer = csv.DictWriter(file, fieldnames=fieldnames)
            writer.writeheader()
            for student in students:
                writer.writerow(student.to_dict())

    def import_from_csv(self, file_path):
        try:
            students = []
            with open(file_path, mode='r', encoding='utf-8') as file:
                reader = csv.DictReader(file)
                for row in reader:
                    row['birth_date'] = date.fromisoformat(row['birth_date'])
                    row['enrollment_date'] = date.fromisoformat(row['enrollment_date'])
                    student = Student.from_dict(row)
                    students.append(student)
            self.save_students(students)
        except FileNotFoundError:
            print(f"文件 {file_path} 未找到。")
        except ValueError as e:
            print(f"日期格式错误: {e}")

    def get_average_height(self):
        students = self.load_students()
        if not students:
            return 0
        total_height = sum(student.height for student in students)
        return total_height / len(students)

    def count_students_by_height_range(self, min_height, max_height):
        students = self.load_students()
        return len([student for student in students if min_height <= student.height <= max_height])

    def count_students_by_enrollment_year(self, year):
        students = self.load_students()
        return len([student for student in students if student.enrollment_date.year == year])

    def count_students_by_age_range(self, min_age, max_age):
        today = date.today()
        students = self.load_students()
        return len([student for student in students if min_age <= today.year - student.birth_date.year <= max_age])

    def backup_data(self, backup_path):
        try:
            with open(self.file_path, mode='r', encoding='utf-8') as src_file, \
                    open(backup_path, mode='w', encoding='utf-8') as dst_file:
                dst_file.write(src_file.read())
            print(f"数据备份到 {backup_path} 成功。")
        except Exception as e:
            print(f"数据备份失败: {e}")

    def restore_data(self, backup_path):
        try:
            with open(backup_path, mode='r', encoding='utf-8') as src_file, \
                    open(self.file_path, mode='w', encoding='utf-8') as dst_file:
                dst_file.write(src_file.read())
            print(f"数据从 {backup_path} 恢复成功。")
        except FileNotFoundError:
            print(f"备份文件 {backup_path} 未找到。")
        except Exception as e:
            print(f"数据恢复失败: {e}")