Stuck at defining relationship in laravel 4 - laravel

Question

i'm trying to understand laravel by creating a messaging application. User should be able to send message to each other. i have made a similar application using core php.
I'm done with login/authentication and migration and now stuck at defining relationship in models;
i have created 3 tables using migrations:
users
conversations
conversations_reply
This is the Schema of:
users table (For storing detail of users)
$table->increments('id');
$table->string('username', 50);
$table->string('password', 50);
$table->string('name', 50);
$table->string('email', 254);
$table->timestamps();
conversations table(For storing conversation between users)
$table->increments('id');
$table->integer('user_one'); //foreign key of one friend from users table
$table->integer('user_two'); //foreign key of second friend from users table
$table->string('ip');
$table->timestamps();
conversations_reply table(For storing Conversation text)
$table->increments('id');
$table->text('reply');
$table->integer('user_id');
$table->integer('conversation_id'); //foreign key of conversations table
$table->string('ip');
$table->timestamps();
Now, i'm trying to define relationships in models as:
User model wil have hasMany relationship with both Conversation and ConversationReply model.
Conversation will have belongsToMany relationship with User model and hasMany relationship with ConversationReply model.
ConversationReply model will have belongsToMany relationship with both User and Conversation model.
Now i'm stuck at defining relationship in the first model(User)and unable to proceed further because i need to define local and foreign key, but i'm unable to do so because conversations table will have 2 foreign keys(of 2 users) and i can define only one foreign key.
Edit: There should be only two members in a conversation and and two users should have only one conversation(like facebook). Their new messages should be added to their old conversations. In conversations table, ip is the ip address of the user who would start the conversation and in the conversations_reply table, ip is the respective ip of the user

Answer 1

There seems to be a little flaw in your abstraction. You have actually designed user1 and user2 as attributes of the Conversation entity, but they are not attributes. Also, what is the IP of a conversation?
Attributes of a Conversation may be topic, start time, end time, amount of messages and things like that.
And then a conversation has members. Not exactly two but many. So you could just create an entity / model ConversationMembers that connects User and Conversation:
conversation_members table:
$table->increments('id');
$table->integer('conversation_id');
$table->integer('user_id');
$table->string('ip');
$table->string('nickname');
and change the conversations table accordingly:
$table->increments('id');
$table->boolean('public);
// other attributes you're interested in
$table->timestamps();
Now you can define the relationships on your models:
Conversation:
public function members()
{
return $this->hasMany('ConversationMember');
}
public function messages()
{
return $this->hasMany('ConversationReply');
}
ConversationMember:
public function user()
{
return $this->belongsTo('User');
}
public function conversation()
{
return $this->belongsTo('Conversation');
}
User:
public function conversations()
{
return $this->hasManyThrough('Conversation', 'ConversationMember');
}
public function replies()
{
return $this->hasMany('ConversationReply');
}
I hope this helps.