<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;

class DocumentAccessLog extends Model
{
    use HasFactory;

    protected $fillable = [
        'document_id',
        'document_version_id',
        'action',
        'user_id',
        'ip_address',
        'user_agent',
        'accessed_at',
    ];

    protected $casts = [
        'accessed_at' => 'datetime',
    ];

    // ==================== Relationships ====================

    /**
     * Get the document this log belongs to
     */
    public function document()
    {
        return $this->belongsTo(Document::class);
    }

    /**
     * Get the document version accessed
     */
    public function version()
    {
        return $this->belongsTo(DocumentVersion::class, 'document_version_id');
    }

    /**
     * Get the user who accessed (null if anonymous)
     */
    public function user()
    {
        return $this->belongsTo(User::class);
    }

    // ==================== Helper Methods ====================

    /**
     * Get action label in Chinese
     */
    public function getActionLabel(): string
    {
        return match($this->action) {
            'view' => '檢視',
            'download' => '下載',
            default => '未知',
        };
    }

    /**
     * Get user display name (anonymous if no user)
     */
    public function getUserDisplay(): string
    {
        return $this->user ? $this->user->name : '匿名訪客';
    }

    /**
     * Get browser from user agent
     */
    public function getBrowser(): string
    {
        if (!$this->user_agent) {
            return '未知';
        }

        if (str_contains($this->user_agent, 'Chrome')) {
            return 'Chrome';
        }
        if (str_contains($this->user_agent, 'Safari')) {
            return 'Safari';
        }
        if (str_contains($this->user_agent, 'Firefox')) {
            return 'Firefox';
        }
        if (str_contains($this->user_agent, 'Edge')) {
            return 'Edge';
        }

        return '未知';
    }

    /**
     * Check if access was by authenticated user
     */
    public function isAuthenticated(): bool
    {
        return $this->user_id !== null;
    }
}