FindUserConversations.swift

public final class User: Model, Content, Hashable {

    public static var schema = "users"

    public init() {}
    
    public init(id: ObjectId? = nil ,phoneNumber: String) {
        self.id = id
        self.phoneNumber = phoneNumber
        self.firstName = nil
        self.lastName = nil
    }
    
    @ID(custom: "id") public var id: ObjectId?
    @Field(key: "phoneNumber") public var phoneNumber: String
    
    @OptionalField(key: "firstName") public var firstName: String?
    @OptionalField(key: "lastName") public var lastName: String?
    @OptionalField(key: "email") public var email: String?
    
    @Children(for: \.$owner) public var event: [Event]
    @Children(for: \.$sender) public var sender: [Message]
    @Children(for: \.$recipient) public var recipient: [Message]

    @Siblings(through: UserConversation.self, from: \.$member, to: \.$conversation)
    public var membersConversaions: [Conversation]

    @Siblings(through: UserConversation.self, from: \.$admin, to: \.$conversation)
    public var adminsConversations: [Conversation]

    @Timestamp(key: "createdAt", on: .create) public var createdAt: Date?
    @Timestamp(key: "updatedAt", on: .update) public var updatedAt: Date?
    @Timestamp(key: "deletedAt", on: .delete) public var deletedAt: Date?
    
    public func hash(into hasher: inout Hasher) {
        hasher.combine(id)
    }
    
    public static func == (lhs: User, rhs: User) -> Bool {
        lhs.id == rhs.id
    }
}
public final class Conversation: Model, Content {
    
    public static var schema = "conversations"
    
    public init() {}
    
    public init(title: String) {
        self.title = title
    }

    @ID(custom: "id") public var id: ObjectId?
    @Field(key: "title") public var title: String

    @Children(for: \.$conversation) public var events: [Event]
    @Children(for: \.$conversation) public var messages: [Message]
    
    @Siblings(through: UserConversation.self, from: \.$conversation, to: \.$member)
    public var members: [User]
    
    @Siblings(through: UserConversation.self, from: \.$conversation, to: \.$admin)
    public var admins: [User]
    
    @Timestamp(key: "createdAt", on: .create) public var createdAt: Date?
    @Timestamp(key: "updatedAt", on: .update) public var updatedAt: Date?
    @Timestamp(key: "deletedAt", on: .delete) public var deletedAt: Date?
    
    public func addUser(userId: ObjectId, req: Request) {
        User.find(userId, on: req.db)
            .unwrap(or: Abort(.notFound, reason: "Cant find user") )
            .flatMap { user in
                    self.$admins.attach(user, on: req.db).flatMap {
                    self.$members.attach(user, on: req.db)
                }
            }
    }

}

public final class UserConversation: Model {
    public static let schema = "user_conversation_pivot"
    
    @ID(custom: "id") public var id: ObjectId?
    
    //@Parent(key: "user_id") var user: User
    @Parent(key: "memberId") public var member: User
    @Parent(key: "adminId") public var admin: User
    @Parent(key: "conversationId")  public var conversation: Conversation

    public init() { }
    
    public init(id: ObjectId? = nil, user: User, conversation: Conversation) throws {
        self.id = id
        self.$member.id = try user.requireID()
        self.$admin.id = try user.requireID()
        self.$conversation.id = try conversation.requireID()
    }
}

User.query(on: req.db)
//.filter(User.self, \._$id == req.payload.userId)
.with(\.$membersConversaions).with(\.$membersConversaions.$pivots)
.with(\.$adminsConversations).with(\.$adminsConversations.$pivots)
.first()
.unwrap(or: Abort(.notFound, reason: "No "))
.map { user in
  //let conversations = user.$membersConversaions.$pivots // + user.$adminsConversations
  print(#line, user)
  // how do i find user conversations (where user are admin + member)
}