//
//  MessageViewModel.swift
//  PaiAi
//
//  Created by mac on 2016/10/19.
//  Copyright © 2016年 FFIB. All rights reserved.
//

import Foundation
import RxSwift
import RxCocoa
import RxDataSources

public struct MessageViewModel {
    
    let messageModel: MessageModel
    
    public init(type: MessageType) {
        self.messageModel = MessageModel(type: type)
    }
    
    public var messageContents: Observable<[AnimatableSectionModel<Int, MessageItem>]> {
        return messageModel.items.distinctUntilChanged().map({ model in
            return [AnimatableSectionModel(model: 0, items: model)]
        })
    }
    
    public func reload(isRefresh: Bool) {
        messageModel.loadContents(isRefresh: isRefresh)
    }
    
    public func preload(indexPath: IndexPath?) {
        guard let indexPath = indexPath,
            indexPath.row == messageModel.items.value.count - 5 else {
                return
        }
        messageModel.loadContents(isRefresh: false)
    }
    
    public func remove(_ item: MessageItem) {
        messageModel.remove(item)
    }
    
    public func removeAll() {
        messageModel.removeAll {
            
        }
    }
    
    public var hasData: Observable<Bool> {
        return messageModel.items.map { $0.count != 0 }
    }
}