from flask import Blueprint, render_template, request, redirect, url_for, flash, session
from flask_login import login_user, logout_user, login_required, current_user
from werkzeug.security import check_password_hash, generate_password_hash
from app.models import db, User, Student
from app.utils.database import safe_commit
from datetime import datetime
import re

auth_bp = Blueprint('auth', __name__)


@auth_bp.route('/login', methods=['GET', 'POST'])
def login():
    if current_user.is_authenticated:
        if current_user.is_admin():
            return redirect(url_for('admin.dashboard'))
        else:
            return redirect(url_for('student.dashboard'))

    if request.method == 'POST':
        student_number = request.form.get('student_number', '').strip()
        password = request.form.get('password', '')
        remember = request.form.get('remember', False)

        if not student_number or not password:
            flash('请输入学号和密码', 'error')
            return render_template('auth/login.html')

        # 查找用户
        user = User.query.filter_by(student_number=student_number).first()

        if user and user.check_password(password):
            if not user.is_active:
                flash('账户已被禁用，请联系管理员', 'error')
                return render_template('auth/login.html')

            # 更新最后登录时间
            user.last_login = datetime.utcnow()
            success, error = safe_commit()

            if not success:
                flash('系统错误，请稍后重试', 'error')
                return render_template('auth/login.html')

            login_user(user, remember=remember)

            # 获取重定向地址
            next_page = request.args.get('next')
            if next_page:
                return redirect(next_page)

            # 根据用户角色重定向
            if user.is_admin():
                flash(f'欢迎回来，管理员！', 'success')
                return redirect(url_for('admin.dashboard'))
            else:
                # 获取学生姓名
                student = Student.query.filter_by(student_number=student_number).first()
                name = student.name if student else student_number
                flash(f'欢迎回来，{name}！', 'success')
                return redirect(url_for('student.dashboard'))
        else:
            flash('学号或密码错误', 'error')

    return render_template('auth/login.html')


@auth_bp.route('/logout')
@login_required
def logout():
    logout_user()
    flash('您已成功退出登录', 'info')
    return redirect(url_for('auth.login'))


@auth_bp.route('/change_password', methods=['GET', 'POST'])
@login_required
def change_password():
    if request.method == 'POST':
        current_password = request.form.get('current_password', '')
        new_password = request.form.get('new_password', '')
        confirm_password = request.form.get('confirm_password', '')

        # 验证输入
        if not all([current_password, new_password, confirm_password]):
            flash('请填写所有密码字段', 'error')
            return render_template('auth/change_password.html')

        # 验证当前密码
        if not current_user.check_password(current_password):
            flash('当前密码不正确', 'error')
            return render_template('auth/change_password.html')

        # 验证新密码与确认密码是否一致
        if new_password != confirm_password:
            flash('新密码与确认密码不匹配', 'error')
            return render_template('auth/change_password.html')

        # 密码长度验证
        if len(new_password) < 6:
            flash('新密码长度至少6位', 'error')
            return render_template('auth/change_password.html')

        # 密码复杂度验证（可选）
        if not re.search(r'^(?=.*[a-zA-Z])(?=.*\d).+$', new_password):
            flash('新密码必须包含字母和数字', 'error')
            return render_template('auth/change_password.html')

        # 检查新密码是否与当前密码相同
        if current_user.check_password(new_password):
            flash('新密码不能与当前密码相同', 'error')
            return render_template('auth/change_password.html')

        try:
            # 更新密码
            current_user.set_password(new_password)
            success, error = safe_commit()

            if success:
                flash('密码修改成功', 'success')
                # 根据用户角色重定向
                if current_user.is_admin():
                    return redirect(url_for('auth.profile'))
                else:
                    return redirect(url_for('auth.profile'))
            else:
                flash(f'密码修改失败: {error}', 'error')

        except Exception as e:
            flash(f'密码修改失败: {str(e)}', 'error')

    return render_template('auth/change_password.html')


@auth_bp.route('/profile')
@login_required
def profile():
    """用户个人信息页面"""
    try:
        if current_user.is_admin():
            # 管理员信息页面
            user_info = {
                'user_id': current_user.user_id,
                'student_number': current_user.student_number,
                'role': current_user.role,
                'is_active': current_user.is_active,
                'last_login': current_user.last_login,
                'created_at': current_user.created_at
            }
            return render_template('auth/admin_profile.html', user_info=user_info)
        else:
            # 学生信息页面
            student = Student.query.filter_by(student_number=current_user.student_number).first()
            user_info = {
                'user_id': current_user.user_id,
                'student_number': current_user.student_number,
                'role': current_user.role,
                'is_active': current_user.is_active,
                'last_login': current_user.last_login,
                'created_at': current_user.created_at,
                # 学生特有信息
                'name': student.name if student else None,
                'gender': student.gender if student else None,
                'grade': student.grade if student else None,
                'phone': student.phone if student else None,
                'supervisor': student.supervisor if student else None,
                'college': student.college if student else None,
                'major': student.major if student else None,
                'degree_type': student.degree_type if student else None,
                'status': student.status if student else None,
                'enrollment_date': student.enrollment_date if student else None
            }
            return render_template('auth/student_profile.html', user_info=user_info, student=student)
    except Exception as e:
        flash(f'获取个人信息失败: {str(e)}', 'error')
        if current_user.is_admin():
            return redirect(url_for('admin.dashboard'))
        else:
            return redirect(url_for('student.dashboard'))