//
//  PhotoDetailListViewModel.swift
//  PaiaiDataKit
//
//  Created by ffib on 2019/3/19.
//  Copyright © 2019 yb. All rights reserved.
//

import Foundation
import RxSwift
import RxCocoa
import RxDataSources

public protocol PhotoDetailListViewModelSynchronization: class {
    func willShow(_ item: PhotoItem)
}

public protocol PhotoDetailListViewModelDelegate: class {
    func didSelected()
}


public final class PhotoDetailListViewModel {
    private var items: BehaviorRelay<[PhotoItem]>
    public var currIndex: Int
    
    public weak var delegate: PhotoDetailListViewModelDelegate?
    public weak var synchronization: PhotoDetailListViewModelSynchronization?
    
    public var content: Observable<[AnimatableSectionModel<Int, PhotoItem>]> {
        return items.map({ model in
            return [AnimatableSectionModel(model: 0, items: model)]
        })
    }
 
    public init(items: [PhotoItem], currIndex: Int) {
        self.items = BehaviorRelay<[PhotoItem]>(value: items)
        self.currIndex = currIndex
    }
    
    public func willShow(index: Int) {
        currIndex = index
        synchronization?.willShow(items.value[currIndex])
    }
    
    public func didSelected() {
        delegate?.didSelected()
    }
}