//
//  LNRoomViewModel.swift
//  Gami
//
//  Created by OneeChan on 2026/3/9.
//

import Foundation
import AtomicXCore
import Combine


protocol LNRoomViewModelNotify {
    func onRoomMessageChanged(messages: [LNRoomMessageItem])
    func onRoomSeatsChanged()
    func onRoomSpeakingUsersChanged()
    func onRoomSeatApplyChanged()
    func onRoomInfoChanged()
    func onMySeatApplyChanged()
    
    func onRoomClosed()
}
extension LNRoomViewModelNotify {
    func onRoomMessageChanged(messages: [LNRoomMessageItem]) { }
    func onRoomSeatsChanged() { }
    func onRoomSpeakingUsersChanged() { }
    func onRoomSeatApplyChanged() { }
    func onRoomInfoChanged() { }
    func onMySeatApplyChanged() { }
    
    func onRoomClosed() { }
}


enum LNRoomSeatNum: Int, CaseIterable, Comparable {
    case none = -1
    case host = 0
    case guest
    case mic1
    case mic2
    case mic3
    case mic4
    case mic5
    case mic6
    case mic7
    case mic8
    
    static func < (lhs: LNRoomSeatNum, rhs: LNRoomSeatNum) -> Bool {
        lhs.rawValue < rhs.rawValue
    }
    
    var title: String {
        if case .host = self {
            .init(key: "A00328")
        } else if case .guest = self {
            .init(key: "A00329")
        } else {
            .init(key: "A00326", rawValue - 1)
        }
    }
    
    var giftHeaderTitle: String {
        if case .host = self {
            .init(key: "A00328")
        } else if case .guest = self {
            .init(key: "A00329")
        } else {
            "Mic \(rawValue - 1)"
        }
    }
}


enum LNApplyingSeatType: Int, Decodable {
    case none
    case guest
    case playmate
}


enum LNApplySeatErrCode: Int {
    case noPermission = 50001
}

class LNRoomViewModel: NSObject {
    let roomId: String
    private let seatStore: LiveSeatStore
    private let guestStore: CoGuestStore
    private let messageStore: BarrageStore
    private let audienceStore: LiveAudienceStore
    
    private(set) var seatsInfo: [LNRoomSeatItem] = []
    private(set) var roomInfo = LNRoomInfo()
    private(set) var speakingUser: [String] = []
    private(set) var lastmessage: Barrage? = nil
    private(set) var seatApplyCount: Int = 0
    private(set) var waitingForSeat: LNApplyingSeatType = .none {
        didSet {
            if oldValue != waitingForSeat {
                LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onMySeatApplyChanged() }
            }
        }
    }
    private let systemHandlerQueue = DispatchQueue(label: "com.gami.room.system.message", attributes: .concurrent)
    
    private var isLoadingGiftList = false
    private(set) var giftList: [LNGiftItemVO] = []
    
    init(roomId: String) {
        self.roomId = roomId
        
        seatStore = LiveSeatStore.create(liveID: roomId)
        guestStore = CoGuestStore.create(liveID: roomId)
        messageStore = BarrageStore.create(liveID: roomId)
        audienceStore = LiveAudienceStore.create(liveID: roomId)
        
        super.init()
        
        setupSeatObservers()
        setupMessageObservers()
        setupRoomInfoObserver()
        setupAudienceEventObservers()
        reloadGiftList()
        
        LNRoomManager.shared.updateCurRoom(self)
    }
    
    func closeRoom() {
        LNRoomManager.shared.closeRoom { success in
            LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomClosed() }
        }
    }
    
    func leaveRoom() {
        LNRoomManager.shared.leaveRoom { success in
            LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomClosed() }
        }
    }
}

// MARK: 麦位管理 - 普通用户
extension LNRoomViewModel {
    var mySeatInfo: LNRoomSeatItem? {
        seatsInfo.first { $0.uid.isMyUid }
    }
    
    private func setupSeatObservers() {
        seatStore.state.subscribe().receive(on: DispatchQueue.main).sink { [weak self] state in
            guard let self else { return }
            let wasOnMic = mySeatInfo != nil
            
            let seats = state.seatList
            var hasChanged = seats.count != seatsInfo.count
            var newSeats: [LNRoomSeatItem] = []
            for seat in seats {
                let item = seatsInfo.first(where: { $0.index.rawValue == seat.index })
                ?? LNRoomSeatItem(index: LNRoomSeatNum(rawValue: seat.index) ?? .none)
                hasChanged = item.update(seat) || hasChanged
                newSeats.append(item)
            }
            if hasChanged {
                seatsInfo = newSeats
                if !wasOnMic, mySeatInfo != nil {
                    // 自己上麦
                    waitingForSeat = .none
                    
                    if roomInfo.forbidAudio {
                        DeviceStore.shared.closeLocalMicrophone()
                    } else {
                        DeviceStore.shared.openLocalMicrophone(completion: nil)
                    }
                }
                LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomSeatsChanged() }
            }
            
            let speakings = state.speakingUsers.filter { $0.value > 0 }.map { $0.key }.sorted { $1 > $0 }
            if speakings != speakingUser {
                speakingUser = speakings
                LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomSpeakingUsersChanged() }
            }
        }.store(in: &cancellables)
    }
    
    // 申请列表
    func getApplyList(type: LNRoomApplySeatType, next: String?, filter: String?,
                      handler: @escaping (LNRoomMicApplyListResponse?) -> Void) {
        LNHttpManager.shared.getApplySeatList(roomId: roomId, searchType: type, filter: filter,
                                              size: 30, next: next ?? "")
        { res, err in
            runOnMain {
                handler(res)
            }
            res?.list.forEach {
                LNProfileManager.shared.updateProfileCache(uid: $0.user.userNo, name: $0.user.nickname, avatar: $0.user.avatar)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
    
    // 申请列表的技能类别
    func getApplyListCategory(handler: @escaping (LNRoomGameCategoryResponse?) -> Void) {
        LNHttpManager.shared.getApplySeatCategory(roomId: roomId) { res, err in
            runOnMain {
                handler(res)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
    
    // 申请上麦
    func applySeat(index: LNRoomSeatNum, handler: @escaping (Bool) -> Void) {
        LNPermissionHelper.requestMicrophoneAccess { [weak self] success in
            guard let self else { return }
            guard success else {
                showToast(.init(key: "A00362"))
                return
            }
            LNHttpManager.shared.applySeat(roomId: roomId, index: index.rawValue) { [weak self] err in
                runOnMain {
                    handler(err == nil)
                }
                if let err {
                    if case .serverError(let code, _) = err,
                       code == LNApplySeatErrCode.noPermission.rawValue {
                        showToast(err.errorDesc, icon: .icAbout.withTintColor(.fill))
                    } else {
                        showToast(err.errorDesc)
                    }
                } else if let self {
                    waitingForSeat = index == .guest ? .guest : index != .host ? .playmate : .none
                }
            }
        }
    }
    
    // 取消上麦申请
    func cancelSeatApply(handler: @escaping (Bool) -> Void) {
        LNHttpManager.shared.cancelApplySeat(roomId: roomId) { [weak self] err in
            runOnMain {
                handler(err == nil)
            }
            if let err {
                showToast(err.errorDesc)
            } else if let self {
                waitingForSeat = .none
            }
        }
    }
    
    // 主动下麦
    func leaveSeat(handler: @escaping (Bool) -> Void) {
        seatStore.leaveSeat { result in
            switch result {
            case .success:
                handler(true)
            case .failure(let err):
                showTencentError(err)
                handler(false)
            }
        }
    }
}


// MARK: 麦位管理 - 管理员
extension LNRoomViewModel {
    // 踢人下麦
    func kickUserOffSeat(uid: String, handler: @escaping (Bool) -> Void) {
        seatStore.kickUserOutOfSeat(userID: uid) { result in
            switch result {
            case .success:
                handler(true)
            case .failure(let err):
                showTencentError(err)
                handler(false)
            }
        }
    }
    
    func clearApplyList(type: LNRoomApplySeatType, handler: @escaping (Bool) -> Void) {
        LNHttpManager.shared.clearApplySeatList(roomId: roomId, searchType: type) { err in
            runOnMain {
                handler(err == nil)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
    
    // 接受上麦申请
    func acceptSeatApply(applyId: String, handler: @escaping (Bool) -> Void) {
        LNHttpManager.shared.handleApplySeat(roomId: roomId, applyId: applyId, accept: true) { err in
            runOnMain {
                handler(err == nil)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
    
    // 拒绝上麦申请
    func rejectSeatApply(applyId: String, handler: @escaping (Bool) -> Void) {
        LNHttpManager.shared.handleApplySeat(roomId: roomId, applyId: applyId, accept: false) { err in
            runOnMain {
                handler(err == nil)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
    
    // 邀请上麦
    func inviteUserToSeat(uid: String, index: LNRoomSeatNum, handler: @escaping (Bool) -> Void) {
        LNHttpManager.shared.inviteUserToSeat(roomId: roomId, uid: uid, index: index.rawValue) { err in
            runOnMain {
                handler(err == nil)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
    
    // 关闭麦位
    func lockSeat(num: Int, handler: @escaping (Bool) -> Void) {
        seatStore.lockSeat(seatIndex: num) { result in
            switch result {
            case .success:
                handler(true)
            case .failure(let err):
                showTencentError(err)
                handler(false)
            }
        }
    }
    
    // 解锁麦位
    func unlockSeat(num: Int, handler: @escaping (Bool) -> Void) {
        seatStore.unlockSeat(seatIndex: num) { result in
            switch result {
            case .success:
                handler(true)
            case .failure(let err):
                showTencentError(err)
                handler(false)
            }
        }
    }
    
    // 用户列表
    func getRoomUserList(next: String?, playmete: Bool, filter: String?,
                         handler: @escaping (LNRoomUserListResponse?) -> Void) {
        LNHttpManager.shared.getRoomUserList(
            roomId: roomId, size: 30, next: next ?? "",
            playmete: playmete, filter: filter)
        { res, err in
            runOnMain {
                handler(res)
            }
            
            res?.list.forEach {
                LNProfileManager.shared.updateProfileCache(uid: $0.user.userNo, name: $0.user.nickname, avatar: $0.user.avatar)
            }
            
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
    
    // 申请列表的技能类别
    func getPlaymateCategory(handler: @escaping (LNRoomGameCategoryResponse?) -> Void) {
        LNHttpManager.shared.getRoomPlaymateCategory(roomId: roomId) { res, err in
            runOnMain {
                handler(res)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
}

// MARK: 麦克风管理 - 普通用户
extension LNRoomViewModel {
    // 关闭自己麦克风
    func muteMySeat() {
        seatStore.muteMicrophone()
    }
    
    // 打开自己麦克风
    func unmuteMySeat(handler: @escaping (Bool) -> Void) {
        let unmute = { [weak self] in
            guard let self else { return }
            seatStore.unmuteMicrophone { result in
                switch result {
                case .success:
                    handler(true)
                case .failure(let err):
                    showTencentError(err)
                    handler(false)
                }
            }
        }
        if DeviceStore.shared.state.value.microphoneStatus == .off {
            DeviceStore.shared.openLocalMicrophone { result in
                switch result {
                case .success:
                    unmute()
                case .failure(let err):
                    showTencentError(err)
                    handler(false)
                }
            }
        } else {
            unmute()
        }
    }
}

// MARK: 麦克风管理 - 管理员
extension LNRoomViewModel {
    // 禁止某人的麦克风
    func muteSeat(uid: String, handler: @escaping (Bool) -> Void) {
        seatStore.closeRemoteMicrophone(userID: uid) { result in
            switch result {
            case .success:
                handler(true)
            case .failure(let err):
                showTencentError(err)
                handler(false)
            }
        }
    }
    
    // 解锁某人麦克风
    func unmuteSeat(uid: String, handler: @escaping (Bool) -> Void) {
        seatStore.openRemoteMicrophone(userID: uid, policy: .unlockOnly) { result in
            switch result {
            case .success:
                handler(true)
            case .failure(let err):
                showTencentError(err)
                handler(false)
            }
        }
    }
}

// MARK: 公屏
extension LNRoomViewModel {
    private func setupMessageObservers() {
        messageStore.state.subscribe().receive(on: DispatchQueue.main).sink { [weak self] state in
            guard let self else { return }
            var newMessage: [Barrage] = []
            if let lastId = lastmessage?.sequence,
               let index = state.messageList.lastIndex(where: { $0.sequence == lastId }) {
                newMessage.append(contentsOf: state.messageList[(index + 1)...])
            } else {
                newMessage.append(contentsOf: state.messageList)
            }
            lastmessage = newMessage.last
            
            systemHandlerQueue.async { [weak self] in
                guard let self else { return }
                var chatMessage: [LNRoomMessageItem] = []
                var systemMessage: [LNRoomPushMessage] = []
                newMessage.forEach {
                    switch $0.messageType {
                    case .text:
                        if let messageItems = LNRoomUserMessage(info: $0)?.messageItems,
                           !messageItems.isEmpty {
                            chatMessage.append(contentsOf: messageItems)
                        }
                    case .custom:
                        if let item = LNRoomPushMessage(info: $0) {
                            systemMessage.append(item)
                            
                            if let messageItems = item.messageItems,
                                !messageItems.isEmpty {
                                chatMessage.append(contentsOf: messageItems)
                            }
                        }
                    default:
                        break
                    }
                }
                if !chatMessage.isEmpty {
                    LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomMessageChanged(messages: chatMessage) }
                }
                handleSystemMessage(messages: systemMessage)
            }
        }.store(in: &cancellables)
    }
    
    func sendChatMessage(text: String, handler: @escaping (Bool) -> Void) {
        messageStore.sendTextMessage(text: text, extensionInfo: [
            LNRoomChatMessageTypeKey: LNRoomChatMessageType.chat.rawValue
        ]) { result in
            switch result {
            case .success:
                handler(true)
            case .failure(let err):
                showTencentError(err)
                handler(false)
            }
        }
    }
}

// MARK: 房间信息
extension LNRoomViewModel {
    private func setupRoomInfoObserver() {
        LNRoomManager.shared.liveListStore.state.subscribe().receive(on: DispatchQueue.main).sink { [weak self] state in
            guard let self else { return }
            if state.currentLive.liveID.isEmpty { return }
            
            if !state.currentLive.roomType.contains(.playmate) {
                showToast(.init(key: "A00389"))
                leaveRoom()
                return
            }
            if roomInfo.update(state.currentLive) {
                LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomInfoChanged() }
            }
            
            let oldCount = seatApplyCount
            if state.currentLive.applySeatCount != seatApplyCount {
                seatApplyCount = state.currentLive.applySeatCount
            }
            if oldCount != seatApplyCount {
                LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomSeatApplyChanged() }
            }
        }.store(in: &cancellables)
        LNRoomManager.shared.liveListStore.liveListEventPublisher.receive(on: DispatchQueue.main).sink { [weak self] event in
            guard let self else { return }
            switch event {
            case .onLiveEnded(let roomId, _, _):
                if self.roomId == roomId {
                    LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomClosed() }
                }
            case .onKickedOutOfLive(let roomId, _, _):
                if self.roomId == roomId {
                    LNEventDeliver.notifyEvent { ($0 as? LNRoomViewModelNotify)?.onRoomClosed() }
                }
            default: break
            }
        }.store(in: &cancellables)
    }
    
    func updateRoomInfo(name: String, cover: String, forbidAudio: Bool, handler: @escaping (Bool) -> Void) {
        LNHttpManager.shared.updateRoom(roomId: roomId, roomTitle: name,
                                        roomCover: cover, forbidAudio: forbidAudio) { err in
            runOnMain {
                handler(err == nil)
            }
            if let err {
                showToast(err.errorDesc)
            }
        }
    }
}

// MARK: 观众事件
extension LNRoomViewModel {
    private func setupAudienceEventObservers() {
        audienceStore.liveAudienceEventPublisher.receive(on: DispatchQueue.main).sink { [weak self] event in
            guard let self else { return }
            switch event {
            case .onAudienceJoined(let info):
                messageStore.appendLocalTip(message: Barrage.welcomeMessage(userInfo: info))
            default:
                break
            }
        }.store(in: &cancellables)
    }
}

// MARK: 礼物
extension LNRoomViewModel {
    func sendGift(gift: LNGiftItemVO, to: [String], count: Int, handler: @escaping (Bool) -> Void) {
        let param = LNSendGiftParams()
        param.roomId = roomId
        param.giftId = gift.id
        param.userIds = to
        param.quantity = count
        LNGiftManager.shared.sendGift(params: param) { success in
            handler(success)
        }
    }
    
    func reloadGiftList() {
        guard !isLoadingGiftList else { return }
        isLoadingGiftList = true
        LNGiftManager.shared.fetchGiftList(roomId: roomId) { [weak self] list in
            guard let self else { return }
            if let list, !list.isEmpty  {
                giftList = list
            }
            isLoadingGiftList = false
        }
    }
}

extension LNRoomViewModel {
    private func handleSystemMessage(messages: [LNRoomPushMessage]) {
        messages.forEach { message in
            if message.cmd == .MicClear,
               let cmd: LNRoomMicClearMessage = message.decodeCmdMessage(),
               cmd.type == self.waitingForSeat {
                self.waitingForSeat = .none
            }
        }
    }
}