<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Paper extends Model
{
    protected $table = 'papers';
    protected $primaryKey = 'id';
    public $incrementing = true;
    protected $keyType = 'int';
    public $timestamps = true;
    
    const CREATED_AT = 'created_at';
    const UPDATED_AT = 'updated_at';
    
    protected $fillable = [
        'id',
        'title',
        'subject',
        'total_score',
        'duration',
        'difficulty_level',
        'created_by',
        'analysis_id', // AI分析记录ID
    ];
    
    protected $casts = [
        'created_at' => 'datetime',
        'updated_at' => 'datetime',
        'total_score' => 'float',
        'duration' => 'integer',
    ];
    
    /**
     * 获取试卷的题目列表
     */
    public function questions()
    {
        return $this->hasMany(PaperQuestion::class, 'paper_id', 'id');
    }

    /**
     * 获取试卷创建者
     */
    public function createdByUser()
    {
        return $this->belongsTo(User::class, 'created_by', 'user_id');
    }

    /**
     * 获取关联的学生
     */
    public function student()
    {
        return $this->belongsTo(Student::class, 'student_id', 'student_id');
    }

    /**
     * 获取关联的教师
     */
    public function teacher()
    {
        return $this->belongsTo(Teacher::class, 'teacher_id', 'teacher_id');
    }
}