<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Paper extends Model
{
    protected $table = 'papers';
    protected $primaryKey = 'paper_id';
    public $incrementing = false;
    protected $keyType = 'string';
    public $timestamps = true;
    
    const CREATED_AT = 'created_at';
    const UPDATED_AT = 'updated_at';
    
    protected $fillable = [
        'paper_id',
        'student_id',
        'teacher_id',
        'paper_name',
        'paper_type',
        'question_count',
        'total_score',
        'status',
        'difficulty_category',
        'analysis_summary',
        'feedback',
        'completed_at',
    ];
    
    protected $casts = [
        'created_at' => 'datetime',
        'updated_at' => 'datetime',
        'completed_at' => 'datetime',
        'total_score' => 'float',
        'question_count' => 'integer',
    ];
    
    /**
     * 获取试卷的题目列表
     */
    public function questions()
    {
        return $this->hasMany(PaperQuestion::class, 'paper_id', 'paper_id');
    }
}