Eloquent pivot model relationships - php

Question

I'm a little confused about how to define a relationship in a Laravel pivot model with extra fields. Here are the table migrations ...
Schema::create('users', function($table) {
$table->increments('id');
$table->string('password', 60);
$table->string('first_name', 50);
$table->string('last_name', 50);
$table->string('email', 255)->unique();
$table->timestamps();
});
Schema::create('accounts', function($table) {
$table->increments('id');
$table->integer('user_id')->unsigned()->unique();
$table->boolean('active')->default(1);
$table->timestamps();
$table->foreign('user_id')->references('id')->on('users')->onDelete('restrict')->onUpdate('cascade');
});
Schema::create('roles', function($table) {
$table->increments('id');
$table->string('name');
});
Schema::create('role_user', function($table) {
$table->integer('role_id')->unsigned();
$table->integer('user_id')->unsigned();
$table->timestamps();
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
$table->foreign('role_id')->references('id')->on('roles')->onDelete('cascade');
});
Schema::create('account_role', function($table) {
$table->integer('account_id')->unsigned();
$table->integer('user_id')->unsigned();
$table->integer('role_id')->unsigned();
$table->timestamps();
$table->unique(array('account_id','user_id'));
$table->foreign('account_id')->references('id')->on('accounts')->onDelete('cascade')->onUpdate('cascade');
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade')->onUpdate('cascade');
$table->foreign('role_id')->references('id')->on('roles')->onDelete('cascade')->onUpdate('cascade');
});
Now you might be wondering "what the heck, why is there a role_user table and a account_role table?" I'll explain.
I have users (free) and accounts (paid). Every account is owned by a user. I also have roles that are site-wide like "admin" in the RolesUsers table. Our business logic requires that account-holders can assign roles to other users for working with the assets owned by the account. In other words if I have a paid account and I want my friend Joe to be able to have some capability to assist with managing my account, I as the account owner can grant him access by assigning him a role on my account. That's what the AccountRoles model is for. As such the account_role table has three fields, user_id, role_id, account_id.
Where I'm stuck is that I can't seem to access the Account model from the pivot. I can access the Account ID. Here are the relevant models:
class User extends Eloquent implements UserInterface, RemindableInterface {
protected $table = 'users';
protected $hidden = array('password');
protected $guarded = array('id');
public function Account() { return $this->hasOne('Account', 'user_id'); }
public function AccountRoles() { return $this->belongsToMany('Role', 'account_role')->withPivot('account_id')->withTimestamps(); }
public function Roles() { return $this->belongsToMany('Role', 'role_user')->withTimestamps(); }
}
class Account extends Eloquent {
protected $table = 'accounts';
public function User() { return $this->belongsTo('User', 'user_id'); }
public function AccountRoles() { return $this->belongsToMany('Role', 'account_role')->withPivot('user_id')->withTimestamps(); }
}
class AccountRole extends Eloquent {
protected $table = 'account_role';
protected $fillable = array();
public function Account() { return $this->belongsTo('Account', 'account_id'); }
}
Here's what works:
$user = User::find($id);
foreach($user->AccountRoles as $account_role)
{
echo 'Account ID: ' . $account_role->pivot->account_id . '<br/>';
echo 'Role: ' . $account_role->name . '<br/>';
}
When I ...
var_dump($account_role->pivot->Account);
... I get "null".
I have also tried ...
$account_role->pivot->Account;
$account_role->pivot->Account();
$account_role->Account;
$account_role->Account();
I have also tried hasOne() rather than belongsTo(). I'm totally lost.
I need $account_role->pivot->Account to return the Account object. Clearly I'm not totally messed up because $account_role->pivot->account_id returns the correct account ID.
What am I missing or where did I mess up? How do I correctly define the relationship in the pivot model to return the Account model???
Thanks in advance for any help you have to offer!