from flask import Blueprint, request, jsonify, session
from werkzeug.security import generate_password_hash, check_password_hash
from app.db import get_db
import functools

bp = Blueprint('auth', __name__, url_prefix='/api')


def login_required(f):
    """登录验证装饰器"""
    @functools.wraps(f)
    def wrapped(*args, **kwargs):
        if 'user_id' not in session:
            return jsonify({'error': '未登录，请先登录'}), 401
        return f(*args, **kwargs)
    return wrapped


def admin_required(f):
    """管理员验证装饰器"""
    @functools.wraps(f)
    def wrapped(*args, **kwargs):
        if 'user_id' not in session:
            return jsonify({'error': '未登录'}), 401
        if session.get('role') != 'admin':
            return jsonify({'error': '无权限，仅管理员可操作'}), 403
        return f(*args, **kwargs)
    return wrapped


@bp.route('/login', methods=['POST'])
def login():
    data = request.get_json()
    username = data.get('username', '').strip()
    password = data.get('password', '')

    if not username or not password:
        return jsonify({'error': '用户名和密码不能为空'}), 400

    conn = get_db()
    user = conn.execute(
        'SELECT * FROM users WHERE username = ?', (username,)
    ).fetchone()
    conn.close()

    if not user or not check_password_hash(user['password_hash'], password):
        return jsonify({'error': '用户名或密码错误'}), 401

    if not user['is_active']:
        return jsonify({'error': '账号已被停用，请联系管理员'}), 403

    session.clear()
    session['user_id'] = user['id']
    session['username'] = user['username']
    session['display_name'] = user['display_name']
    session['role'] = user['role']
    session.permanent = True

    return jsonify({
        'success': True,
        'user': {
            'id': user['id'],
            'username': user['username'],
            'display_name': user['display_name'],
            'role': user['role']
        }
    })


@bp.route('/logout', methods=['POST'])
def logout():
    session.clear()
    return jsonify({'success': True})


@bp.route('/me', methods=['GET'])
@login_required
def me():
    return jsonify({
        'user': {
            'id': session['user_id'],
            'username': session['username'],
            'display_name': session['display_name'],
            'role': session['role']
        }
    })


@bp.route('/register', methods=['POST'])
def register():
    """邀请码注册"""
    data = request.get_json()
    invite_code = data.get('invite_code', '').strip()
    username = data.get('username', '').strip()
    password = data.get('password', '')
    display_name = data.get('display_name', '').strip()

    if not invite_code or not username or not password:
        return jsonify({'error': '邀请码、用户名、密码均不能为空'}), 400

    if len(username) < 2 or len(username) > 20:
        return jsonify({'error': '用户名长度2-20个字符'}), 400

    if len(password) < 6:
        return jsonify({'error': '密码至少6位'}), 400

    conn = get_db()
    try:
        # 验证邀请码
        invite = conn.execute(
            'SELECT * FROM invite_codes WHERE code = ? AND is_used = 0',
            (invite_code,)
        ).fetchone()
        if not invite:
            return jsonify({'error': '邀请码无效或已被使用'}), 400

        # 检查用户名是否已存在
        existing = conn.execute(
            'SELECT id FROM users WHERE username = ?', (username,)
        ).fetchone()
        if existing:
            return jsonify({'error': '用户名已存在，请换一个'}), 400

        # 如果用户没填显示名，用邀请码绑定的编导姓名
        if not display_name:
            display_name = invite['editor_name']

        # 创建用户
        cursor = conn.execute(
            'INSERT INTO users (username, display_name, password_hash, role) VALUES (?, ?, ?, ?)',
            (username, display_name, generate_password_hash(password), 'editor')
        )
        user_id = cursor.lastrowid

        # 标记邀请码已使用
        conn.execute(
            'UPDATE invite_codes SET is_used = 1, used_by_user_id = ?, used_at = CURRENT_TIMESTAMP WHERE id = ?',
            (user_id, invite['id'])
        )
        conn.commit()

        return jsonify({
            'success': True,
            'message': f'注册成功！欢迎 {display_name}'
        })
    except Exception as e:
        conn.rollback()
        return jsonify({'error': f'注册失败: {str(e)}'}), 500
    finally:
        conn.close()