<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\SoftDeletes;

class Article extends Model
{
    use SoftDeletes;

    protected $fillable = [
        'category_id',
        'user_id',
        'title',
        'slug',
        'summary',
        'body',
        'cover',
        'author',
        'status',
        'template',
        'seo_title',
        'seo_description',
        'published_at',
    ];

    protected $casts = [
        'category_id' => 'integer',
        'published_at' => 'datetime',
    ];

    public const TEMPLATES = [
        'standard' => '标准文章',
        'tech' => '技术文档',
        'feature' => '专题报道',
    ];

    public function category(): BelongsTo
    {
        return $this->belongsTo(Category::class, 'category_id');
    }

    public function user(): BelongsTo
    {
        return $this->belongsTo(User::class, 'user_id');
    }

    /**
     * 可见性作用域（与 forum 一致）：
     * - 审核员(articles.moderate)：看全部
     * - 登录用户：看已审 + 自己投稿（无论状态）
     * - 游客：仅看已审
     */
    public function scopeVisibleTo($query, ?User $user = null)
    {
        if ($user && $user->canPerm('articles.moderate')) {
            return $query;
        }

        if ($user) {
            return $query->where(function ($q) use ($user) {
                $q->where('status', 'approved')->orWhere('user_id', $user->id);
            });
        }

        return $query->where('status', 'approved');
    }

    public function scopePublished($query)
    {
        return $query->where('status', 'approved')
            ->whereNotNull('published_at')
            ->orderByDesc('published_at');
    }

    /**
     * 前台可见文章：已审核通过(approved) 且已设定发布时间。
     * 用户自己的待审(pending)/驳回(rejected) 由控制器单独查询，不进此作用域。
     */
    public function scopeVisiblePublic($query)
    {
        return $query->where('status', 'approved')
            ->whereNotNull('published_at');
    }

    /**
     * 前台 SEO 标题：优先用文章自定义，否则回退到标题。
     */
    public function seoTitle(): string
    {
        return $this->seo_title ?: $this->title;
    }

    public function seoDescription(): string
    {
        return $this->seo_description ?: ($this->summary ?: $this->title);
    }
}