//
//  GroupViewController.swift
//  QuickLocation
//

import UIKit
import RxSwift
import RxCocoa
import RxDataSources
import SDCycleScrollView
import ObjectMapper

final class GroupViewController: BaseViewController {

    override var isNavigationBarHidden: Bool { true }

    fileprivate var rootView: GroupView!
    private let viewModel = GroupViewModel()

    /// 行程页当前圈子数据
    private var itineraryGroupModel: GroupModel?
    private var itinerarySchedules: [ScheduleModel] = []

    override func loadView() {
        rootView = GroupView(frame: UIScreen.main.bounds)
        view = rootView
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        bindViewModel()
        reactiveAction()
        observeTableViews()
        bindItineraryPage()
        requestRecommandGroup()
        requestGroupInfo()

        guard let config = AppContextManager.shared.systemConfig else { return }
        rootView.cycleScrollView.imageURLStringsGroup = config.groupBannerList
    }

    // MARK: - OpenIM
    private var hasSetupIMListeners = false

    /// 进入页面加载 IM 会话：圈子集合已由业务接口给出，这里只补未读/最后一条
    private func loadIMData() {
        GroupIMService.shared.ensureLogin { [weak self] success in
            guard let self = self else { return }
            guard success else { return }
            self.setupIMListenersIfNeeded()
            self.refreshIMData()
        }
    }

    /// 注册 IM 监听（仅一次）：会话变化更新未读/时间；群组变化后重拉会话
    private func setupIMListenersIfNeeded() {
        guard !hasSetupIMListeners else { return }
        hasSetupIMListeners = true

        GroupIMService.shared.setConversationListener { [weak self] conversations in
            DispatchQueue.main.async {
                self?.viewModel.updateConversations(conversations)
            }
        }

        GroupIMService.shared.setGroupListener { [weak self] in
            GroupIMService.shared.getConversationList { conversations in
                DispatchQueue.main.async {
                    self?.viewModel.loadConversations(conversations)
                }
            }
        }
    }

    private func refreshIMData() {
        GroupIMService.shared.getConversationList { [weak self] conversations in
            DispatchQueue.main.async {
                DLToast.dismiss()
                self?.viewModel.loadConversations(conversations)
            }
        }
    }

    // MARK: - Bindings
    private func bindViewModel() {
        viewModel.output.hotGroups
            .observe(on: MainScheduler.asyncInstance)
            .bind(to: rootView.hotGroupsCollectionView.rx.items(dataSource: hotGroupDataSource))
            .disposed(by: disposeBag)

        viewModel.output.createdSections
            .observe(on: MainScheduler.asyncInstance)
            .bind(to: rootView.createdTableView.rx.items(dataSource: createdDataSource))
            .disposed(by: disposeBag)

        viewModel.output.joinedSections
            .observe(on: MainScheduler.asyncInstance)
            .bind(to: rootView.joinedTableView.rx.items(dataSource: joinedDataSource))
            .disposed(by: disposeBag)

        rootView.hotGroupsCollectionView.rx.modelSelected(GroupInfoModel.self)
            .subscribe(viewModel.hotGroupCellAction.inputs)
            .disposed(by: disposeBag)
    }

    private func reactiveAction() {
        rootView.createGroupBtn.rx.tapGesture
            .subscribe(onNext: { _ in
                AppRouter.push(Route.createGroup)
            })
            .disposed(by: disposeBag)

        rootView.joinGroupBtn.rx.tapGesture
            .subscribe(onNext: { _ in
                AppRouter.push(Route.joinGroup)
            })
            .disposed(by: disposeBag)

        // 子 Tab：全部圈子(0=joined) / 我的圈子(1=created)
        rootView.joinedTabLabel.rx.tapGesture
            .subscribe(onNext: { [weak self] _ in self?.switchToSegment(0) })
            .disposed(by: disposeBag)

        rootView.createdTabLabel.rx.tapGesture
            .subscribe(onNext: { [weak self] _ in self?.switchToSegment(1) })
            .disposed(by: disposeBag)

        // 顶栏：圈子 / 行程
        rootView.circleTabLabel.rx.tapGesture
            .subscribe(onNext: { [weak self] _ in
                self?.rootView.selectTopTab(at: 0)
            })
            .disposed(by: disposeBag)

        rootView.itineraryTabLabel.rx.tapGesture
            .subscribe(onNext: { [weak self] _ in
                guard let self = self else { return }
                self.rootView.selectTopTab(at: 1)
                self.refreshItineraryPage()
            })
            .disposed(by: disposeBag)

        Observable.merge(
            rootView.createdTableView.rx.modelSelected(GroupCellData.self).asObservable(),
            rootView.joinedTableView.rx.modelSelected(GroupCellData.self).asObservable()
        )
        .subscribe(onNext: { data in
            let groupId = data.group.group_key
            guard !groupId.isEmpty else { return }
            AppRouter.push(Route.groupChat, userInfo: ["groupId": groupId])
        })
        .disposed(by: disposeBag)

        // MQTT join/leave/dismiss 后刷新群列表
        NotificationCenter.default.rx.notification(.RefreshIMGroupListNotification)
            .subscribe(onNext: { [weak self] _ in
                self?.requestGroupInfo()
            })
            .disposed(by: disposeBag)

        NotificationCenter.default.rx.notification(.RefreshUserConfigNotification)
            .subscribe(onNext: { [weak self] _ in
                self?.requestRecommandGroup()
                self?.requestGroupInfo()

                guard let config = AppContextManager.shared.systemConfig else { return }
                self?.rootView.cycleScrollView.imageURLStringsGroup = config.groupBannerList
            })
            .disposed(by: disposeBag)

        NotificationCenter.default.rx.notification(.RefreshGroupInfoNotification)
            .subscribe(onNext: { [weak self] _ in
                self?.refreshItineraryPage()
            })
            .disposed(by: disposeBag)
    }

    private func bindItineraryPage() {
        let page = rootView.itineraryPage

        page.onSwitchGroup = { [weak self] in
            self?.showSwitchGroupPop()
        }

        page.onSelectSchedule = { model in
            AppRouter.push(Route.scheduleDetail, userInfo: ["scheduleJson": model.toJSON()])
        }

        page.onDeleteSchedule = { [weak self] model in
            self?.deleteSchedule(model)
        }
    }

    private func switchToSegment(_ index: Int) {
        rootView.selectSegment(at: index)
        let offset = CGPoint(x: CGFloat(index) * rootView.segmentScrollView.bounds.width, y: 0)
        rootView.segmentScrollView.setContentOffset(offset, animated: false)
    }

    // MARK: - 行程页
    private func refreshItineraryPage() {
        GroupService.groupInfo().subscribe(onNext: { [weak self] response in
            guard let self = self, let model = response.model else { return }
            self.itineraryGroupModel = model
            let current = model.groups.first(where: { $0.group_key == model.default_group_key })
            self.rootView.itineraryPage.updateGroupName(current?.name ?? "")
            self.requestItinerarySchedules(groupKey: model.default_group_key)
        }).disposed(by: disposeBag)
    }

    private func requestItinerarySchedules(groupKey: String) {
        guard !groupKey.isEmpty else {
            itinerarySchedules = []
            rootView.itineraryPage.reloadSchedules([])
            return
        }
        ItineraryService.groupScheduleList(groupKey: groupKey)
            .subscribe(onNext: { [weak self] response in
                guard let self = self else { return }
                self.itinerarySchedules = response.list
                self.rootView.itineraryPage.reloadSchedules(response.list)
            })
            .disposed(by: disposeBag)
    }

    private func showSwitchGroupPop() {
        guard let groupModel = itineraryGroupModel else {
            refreshItineraryPage()
            return
        }
        GroupListPopView.show(groupModel: groupModel) { [weak self] groupKey in
            guard let self = self, let key = groupKey else { return }
            GroupService.operate(opType: "setdefault", requestData: ["group_key": key])
                .subscribe(onNext: { _ in
                    NotificationCenter.default.post(name: .RefreshGroupInfoNotification, object: nil)
                })
                .disposed(by: self.disposeBag)
        }
    }

    private func deleteSchedule(_ model: ScheduleModel) {
        guard !model.id.isEmpty else { return }
        DLToast.showLoading()
        ItineraryService.delete(id: model.id)
            .subscribe(onNext: { [weak self] _ in
                DLToast.dismiss()
                guard let self = self else { return }
                self.itinerarySchedules.removeAll { $0.id == model.id }
                self.rootView.itineraryPage.reloadSchedules(self.itinerarySchedules)
            }, onError: { _ in
                DLToast.dismiss()
            })
            .disposed(by: disposeBag)
    }

    // MARK: - 内层 tableView 滚动
    private func observeTableViews() {
        rootView.createdTableView.rx.didScroll
            .observe(on: MainScheduler.asyncInstance)
            .subscribe(onNext: { [weak self] in
                guard let self = self else { return }
                self.rootView.handleTableViewScroll(self.rootView.createdTableView)
            })
            .disposed(by: disposeBag)

        rootView.joinedTableView.rx.didScroll
            .observe(on: MainScheduler.asyncInstance)
            .subscribe(onNext: { [weak self] in
                guard let self = self else { return }
                self.rootView.handleTableViewScroll(self.rootView.joinedTableView)
            })
            .disposed(by: disposeBag)
    }

    // MARK: - dataSource
    private lazy var hotGroupDataSource: RxCollectionViewSectionedReloadDataSource<HotGroupListSectionModel> = {
        RxCollectionViewSectionedReloadDataSource<HotGroupListSectionModel> { datasource, collectionView, indexPath, model in
            let cell: HotGroupCell = collectionView.dequeueReusableCell(for: indexPath)
            cell.configure(model)
            return cell
        }
    }()

    private lazy var createdDataSource: RxTableViewSectionedReloadDataSource<CircleListSectionModel> = {
        RxTableViewSectionedReloadDataSource<CircleListSectionModel> { _, tableView, indexPath, model in
            let cell: CircleGroupCell = tableView.dequeueReusableCell(for: indexPath)
            cell.configure(model)
            return cell
        }
    }()

    private lazy var joinedDataSource: RxTableViewSectionedReloadDataSource<CircleListSectionModel> = {
        RxTableViewSectionedReloadDataSource<CircleListSectionModel> { _, tableView, indexPath, model in
            let cell: CircleGroupCell = tableView.dequeueReusableCell(for: indexPath)
            cell.configure(model)
            return cell
        }
    }()

    // MARK: - API
    private func requestRecommandGroup() {
        GroupService.recommand(count: 5).subscribe(onNext: { response in
            self.viewModel.loadHotGroupData(response.list)
        }).disposed(by: disposeBag)
    }

    private func requestGroupInfo() {
        GroupService.groupInfo().subscribe { response in
            guard let model = response.model else { return }
            self.viewModel.applyBusinessGroups(model.groups)
            self.loadIMData()
        }.disposed(by: disposeBag)
    }
}