//
//  MineGroupViewController.swift
//  PaiAi
//
//  Created by zhengjianfei on 16/4/4.
//  Copyright © 2016年 FFIB. All rights reserved.
//

import UIKit
import RxSwift
import RxCocoa
import RxDataSources
import PaiaiDataKit
import PaiaiUIKit
import PullToRefresh

final class MineGroupViewController: UIViewController {

    // MARK: Storyboard property
    @IBOutlet weak var tableView: UITableView!

    // MARK: data property
    fileprivate let disposeBag = DisposeBag()
    var viewModel: MineGroupViewModel!
    
    // MARK: view function
    override func viewDidLoad() {
        super.viewDidLoad()
        setup()
        binding()
        setNavigationBar()
    }
    
    private func setNavigationBar() {
        title = "我的照片群"
    }
    
    private func setup() {
        setupReloadControl()
        setupLoadingControl()
    }
    
    private func setupReloadControl() {
        tableView.addPullToRefresh(PullToRefresh()) {
            [weak self] in
            guard let `self` = self else { return }
            self.viewModel.reload()
        }
        tableView.startRefreshing(at: .top)
    }
    
    private func setupLoadingControl() {
        tableView.addPullToRefresh(PullToRefresh(position: .bottom)) {
            [weak self] in
            guard let `self` = self else { return }
            self.viewModel.preload()
        }
    }
}

fileprivate extension MineGroupViewController {
    func observeMessage() {
        viewModel.showMessage
            .asDriver { _ in fatalError("Unexpected error from error messages observable.") }
            .drive(onNext: { message in
                Toast.show(message: message)
            })
            .disposed(by: disposeBag)
    }
}

fileprivate extension MineGroupViewController {
    var dataSource: RxTableViewSectionedAnimatedDataSource<AnimatableSectionModel<Int, GroupItem>> {
        return RxTableViewSectionedAnimatedDataSource<AnimatableSectionModel<Int, GroupItem>>(configureCell: { (dataSource, tableView, indexPath, item) in
            let cell = tableView.dequeueReusableCell(withIdentifier: "groupCell", for: indexPath) as! GroupCell
            cell.setInfo(item)
            return cell
        }, canEditRowAtIndexPath: { _, _ in true })
    }
    
    func binding() {
        observeMessage()
        bindViewModelToTableView()
        bindTableViewToViewModel()
        bindViewModelToRefreshing()
    }
    
    func bindViewModelToTableView() {
        viewModel.contents
            .bind(to: tableView.rx.items(dataSource: dataSource))
            .disposed(by: disposeBag)
    }
    
    func bindTableViewToViewModel() {
        tableView.rx.itemDeleted
            .asDriver()
            .drive(onNext: { [unowned self] in self.viewModel.remove(of: $0.row) })
            .disposed(by: disposeBag)
        
        tableView.rx.modelSelected(GroupItem.self)
            .asDriver()
            .drive(onNext: { [unowned self] in self.viewModel.didSelect($0) })
            .disposed(by: disposeBag)
        
        tableView.rx.willDisplayCell
            .asDriver()
            .drive(onNext: { [unowned self] in self.preload(indexPath: $0.indexPath) })
            .disposed(by: disposeBag)
    }
    
    func preload(indexPath: IndexPath) {
        guard indexPath.row == tableView.numberOfRows(inSection: 0) - 5 else { return }
        tableView.startRefreshing(at: .bottom)
    }
    
    func bindViewModelToRefreshing() {
        viewModel.isLoading
            .asDriver(onErrorJustReturn: true)
            .drive(onNext: {[weak self] flag in
                guard let `self` = self else { return }
                if flag {
                    self.tableView.endRefreshing(at: .top)
                } else {
                    self.tableView.endRefreshing(at: .bottom)
                }
            }).disposed(by: disposeBag)
        
        viewModel.hasMoreData
            .asDriver(onErrorJustReturn: true)
            .drive(onNext: {[weak self] flag in
                guard let `self` = self else { return }
                if flag {
                    if self.tableView.bottomPullToRefresh == nil {
                        self.setupLoadingControl()
                    }
                } else {
                    //                    self.tableViewt
                }
            }).disposed(by: disposeBag)
    }
}

extension MineGroupViewController: NavigationBackViewController {}