Same Foreing Key Twice That Refers to One Model - laravel

Question

I need to make an advice platform for products. User can make advices under product section. So product has many advices. Also advices belongsTo product. But on product_advices table i have product_id and product_advice_id these both refers to id on products table.
So here is the problem. I can take advices from product_advices table which refers to product_id. But how can i take the other one as product.
product->advices to show advice and user message
each advices as advice and advice->product->name to show adviced product name
I couldn't make a relationship with eloquent between them.
//Product Model
public function advices()
{
return $this->hasMany('App\ProductAdvice', 'product_id');
}
//ProductAdvice Model
protected $table = 'product_advices';
public function product() {
return $this->belongsTo('App\Product', 'product_id');
}
//Product Advice Table
Schema::create('product_advices', function (Blueprint $table) {
$table->increments('id');
$table->integer('user_id')->unsigned();
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
$table->text('body')->nullable();
$table->integer('product_id')->unsigned();
$table->foreign('product_id')->references('id')->on('products')->onDelete('cascade');
$table->integer('product_advice_id')->unsigned();
$table->foreign('product_advice_id')->references('id')->on('products')->onDelete('cascade');
$table->timestamps();
});
For example :
Iphone has many advices by users.
Iphone->advices brings the advices from product_advices that Iphone belongs to product_id column.
When User recommends Samsung Galaxy S10 to Iphone. Samsung refers to product_advice_id column on product_advices table. But how to show Samsung Galaxy S10 as a product.
$advice->product->name returns Iphone instead of Samsung Galaxy S10.

Answer 1

EDIT 2
After your answer, I understood what you want.
Just update your ProductAdvice model to have another relationship, like:
class ProductAdvice extends Model
{
public function product()
{
return $this->belonsTo('App\Product', 'product_id');
}
public function related()
{
return $this->belonsTo('App\Product', 'product_advice_id');
}
}
Then you can do:
$product = Apple
$product->advices->message = 'blablabla'
$product->advices->related = 'ProductX'
If you need to to the inverse order, $advice->product->related add the same relationship on your Product model.
EDIT 1
Sorry, you edited the post after my answer...
Could you explain the 'product_advice_id' necessity? You already have the product_id.
Unless you want a pivot table, like: Product -> ProductAdvice -> Advice, which is not needed in your case, since you can just put the advice information in the Advice table and link it to the product (belongsTo), removing the necessity of the ProductAdvice pivot.
I think your structure should be like this:
Product model with all the product data
ProductAdvice model with product_id and the advice information (message, rating, etc)
Then, your Product hasMany Advices and your Advice belongsTo Product:
class Product extends Model
{
public function advices()
{
return $this->hasMany('App\ProductAdvice', 'product_id');
}
}
class ProductAdvice extends Model
{
public function product()
{
return $this->belonsTo('App\Product', 'product_id');
}
}
Finally, you can query the advices of a specific Product to get the advice information:
$product->advices->message
$product->advices->rating
Or query the product name if you have an advice:
$advice->product->name

Answer 2

So, If understand well, you want and advice from product A to return the name of product B.
You can make this by creating multiple method related to the same model.
Your models will look similar at this:
class Product extends Model
{
public function advices()
{
return $this->hasMany('App\ProductAdvice', 'product_id');
}
public function relations()
{
return $this->hasMany('App\ProductAdvice', 'related_id');
}
}
class ProductAdvice extends Model
{
public function product()
{
return $this->belonsTo('App\Product', 'product_id');
}
public function relation()
{
return $this->belonsTo('App\Product', 'related_id');
}
}
Then you will have to create another column in your talbe name :related_id (it could be something else, just made it match in your model. You can also change relations() and relation() method to whatever name you want.)
After this it's how you store your data. You have to make your code associate the good product model into your product_id and into related_id. This way. You can have $advice->product->name === 'iPhone' && $advice->relation->name === 'Samsung S10'

Answer 3

Found a solution like this for now.
//ProductAdvice Model
protected $table = 'product_advices';
public function user()
{
return $this->belongsTo('App\User');
}
public function product() {
return $this->belongsTo('App\Product', 'product_id');
}
public function advicedProduct()
{
return Product::where('id', $this->product_advice_id)->first();
}
//Product Model
public function advices()
{
return $this->hasMany('App\ProductAdvice', 'product_id');
}
How i show it on view
#foreach($product->advices as $advice)
<li>{{ $advice->body }} - {{ $advice->advicedProduct()->name }}</li>
#endforeach