//
//  GroupChatVC.swift
//  QuickLocation
//
//  Created by 八条 on 2026/6/4.
//

import UIKit
import RxSwift
import RxCocoa
import RxDataSources
import OpenIMSDK
import AVFoundation
import AudioToolbox
import HXPHPicker
import IQKeyboardManagerSwift

final class GroupChatVC: BaseViewController {

    override var isNavigationBarHidden: Bool { true }

    fileprivate var rootView: GroupChatView!
    private let viewModel = GroupChatViewModel()
    private var msgListener: MessageListenerProxy?

    // MARK: - Init
    init(groupId: String) {
        viewModel.groupId = groupId
        super.init(nibName: nil, bundle: nil)
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

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

    override func viewDidLoad() {
        super.viewDidLoad()
        fd_interactivePopDisabled = true
        bindViewModel()
        requestGroupInfoByKey()
        reactiveAction()
        setupMessageListener()
        setupVoiceRecording()
        setupPanelDismiss()
        setupKeyboard()
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        IQKeyboardManager.shared.isEnabled = false
        IQKeyboardManager.shared.resignOnTouchOutside = false
    }
    
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
//        if !hasScrolledToBottom {
//            hasScrolledToBottom = true
//            scrollToBottom()
//        }
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        VoicePlayerManager.shared.stop()
        IQKeyboardManager.shared.isEnabled = true
        IQKeyboardManager.shared.resignOnTouchOutside = true
    }

    // MARK: - Keyboard
    private func setupKeyboard() {
        // 键盘升起
        NotificationCenter.default.rx.notification(UIResponder.keyboardWillShowNotification)
            .subscribe(onNext: { [weak self] noti in
                guard let self = self,
                      let userInfo = noti.userInfo,
                      let frame = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect
                else { return }
                let height = frame.height
                let duration = (userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double) ?? 0.25
                // 收起表情/语音面板
                self.rootView.dismissAllPanels(excludeTextField: true)
                UIView.animate(withDuration: duration) {
                    self.rootView.bottomBar.layoutChain.bottom(height + kSafeBottomMargin + 20)
                }
                self.scrollToBottom()
            })
            .disposed(by: disposeBag)
    }

    private func setupPanelDismiss() {
        // 用户开始拖拽 tableview 时收起面板
        rootView.tableView.panGestureRecognizer.rx.event
            .filter { $0.state == .began }
            .subscribe(onNext: { [weak self] _ in
                self?.rootView.dismissAllPanels()
            })
            .disposed(by: disposeBag)

        // 点击 cell 收起面板
        rootView.tableView.rx.itemSelected
            .subscribe(onNext: { [weak self] _ in
                self?.rootView.dismissAllPanels()
            })
            .disposed(by: disposeBag)
    }

    // MARK: - Bindings
    private func bindViewModel() {
        viewModel.output.messages
            .skip(1)
            .map { [ChatSectionModel(model: "", items: $0)] }
            .observe(on: MainScheduler.asyncInstance)
            .bind(to: rootView.tableView.rx.items(dataSource: dataSource))
            .disposed(by: disposeBag)

        viewModel.output.messages
            .skip(1)
            .observe(on: MainScheduler.asyncInstance)
            .subscribe(onNext: { [weak self] _ in
                self?.scrollToBottom()
            })
            .disposed(by: disposeBag)

        let emojiItems = UITableViewCell.emojiFileNames.map { $0 }
        Observable.just([SectionModel(model: "", items: emojiItems)])
            .bind(to: rootView.emojiCollectionView.rx.items(dataSource: emojiDataSource))
            .disposed(by: disposeBag)
    }

    private var hasScrolledToBottom = false

    private func scrollToBottom() {
        let count = dataSource.sectionModels.first?.items.count ?? 0
        guard count > 0 else { return }
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
            self.rootView.tableView.layoutIfNeeded()
            let indexPath = IndexPath(row: count - 1, section: 0)
            self.rootView.tableView.scrollToRow(at: indexPath, at: .bottom, animated: false)
        }
    }

    private lazy var emojiDataSource: RxCollectionViewSectionedReloadDataSource<SectionModel<String, String>> = {
        RxCollectionViewSectionedReloadDataSource<SectionModel<String, String>> { _, collectionView, indexPath, name in
            let cell: EmojiPanelCell = collectionView.dequeueReusableCell(for: indexPath)
            if let path = Bundle.main.path(forResource: name, ofType: "json") {
                cell.configure(path: path)
            }
            return cell
        }
    }()

    // MARK: - Message Listener
    private func setupMessageListener() {
        msgListener = MessageListenerProxy { [weak self] msg in
            guard let self = self, msg.groupID == self.viewModel.groupId else { return }
            self.viewModel.onReceiveMessage(msg)
        }
        OIMManager.callbacker.addAdvancedMsgListener(listener: msgListener!)
    }

    // MARK: - Actions
    private func reactiveAction() {
        rootView.backBtn.rx.tap
            .subscribe(onNext: { _ in
                AppRouter.shared.popOrDismiss()
            })
            .disposed(by: disposeBag)

        // 语音按钮
        rootView.voiceBtn.rx.tap.subscribe(onNext: { [weak self] _ in
            guard let self = self else { return }
            let status = AVCaptureDevice.authorizationStatus(for: .audio)
            switch status {
            case .authorized:
                break
            case .notDetermined:
                AVAudioSession.sharedInstance().requestRecordPermission { granted in
                    guard granted else { return }
                    DispatchQueue.main.async {
                        self.rootView.dismissAllPanels()
                        self.showSpeakPanel()
                    }
                }
                return
            default:
                Permission.openAppSetting(title: "请开启麦克风权限",
                                          message: "请在iPhone的“设置-隐私-麦克风”选项中允许\(kAppName)访问你的麦克风。")
                return
            }
            self.rootView.dismissAllPanels()
            self.showSpeakPanel()
        })
        .disposed(by: disposeBag)
        
        // 键盘按钮
        rootView.voiceRecordView.keyboardBtn.rx.tap
            .subscribe(onNext: { [weak self] _ in
                guard let self = self else { return }
                self.rootView.dismissAllPanels()
                self.rootView.textField.becomeFirstResponder()
            })
            .disposed(by: disposeBag)
        
        // 表情按钮
        rootView.emojiBtn.rx.tap
            .subscribe(onNext: { [weak self] _ in
                guard let self = self else { return }
                self.showEmojiPanel()
            })
            .disposed(by: disposeBag)

        rootView.voiceRecordView.emojiBtn.rx.tap
            .subscribe(onNext: { [weak self] _ in
                guard let self = self else { return }
                self.rootView.dismissAllPanels()
                self.showEmojiPanel()
            })
            .disposed(by: disposeBag)
        
        // 表情面板点击
        rootView.emojiCollectionView.rx.modelSelected(String.self)
            .subscribe(onNext: { [weak self] name in
                guard let self = self, let idx = UITableViewCell.emojiFileNames.firstIndex(of: name) else { return }
                self.viewModel.input.sendMessage.onNext("js_emoji:\(idx)")
            })
            .disposed(by: disposeBag)

        // ➕按钮
        Observable.merge(
            rootView.addBtn.rx.tap.asObservable(),
            rootView.voiceRecordView.addBtn.rx.tap.asObservable()
        )
        .subscribe(onNext: { [weak self] in
            guard let self = self else { return }
            self.rootView.dismissAllPanels()
            self.showAlbum()
        })
        .disposed(by: disposeBag)
        
        let sendText = Observable.merge(
            rootView.sendBtn.rx.tap.map { [weak self] _ in self?.rootView.textField.text ?? "" },
            rootView.textField.rx.controlEvent(.editingDidEndOnExit)
                .map { [weak self] _ in self?.rootView.textField.text ?? "" }
        )
        .filter { !$0.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty }
        .do(onNext: { [weak self] _ in self?.rootView.textField.text = "" })

        sendText
            .bind(to: viewModel.input.sendMessage)
            .disposed(by: disposeBag)
        
        // 设置
        rootView.settingBtn.rx.tap
            .subscribe(onNext: { [weak self] _ in
                guard let self = self else { return }
                AppRouter.push(Route.groupSetting, userInfo: ["groupId": self.viewModel.groupId])
            })
            .disposed(by: disposeBag)
    }
    
    // MARK: - 显示语音面板
    private func showSpeakPanel() {
        let show = rootView.voiceRecordView.isHidden
        rootView.voiceRecordView.isHidden = !show
        let offset: CGFloat = show ? 252 : 0
        UIView.animate(withDuration: 0.25) {
            self.rootView.bottomBar.layoutChain.bottom(show ? offset - self.rootView.bottomBar.dl.height : kSafeBottomMargin + 20)
            self.rootView.voiceRecordView.layoutChain.bottom(offset - 252 + kSafeBottomMargin)
        }
        scrollToBottom()
    }
    
    // MARK: - 显示表情面板
    private func showEmojiPanel() {
        let show = self.rootView.emojiPanelView.isHidden
        self.rootView.emojiPanelView.isHidden = !show
        let offset: CGFloat = show ? 220 : 0
        UIView.animate(withDuration: 0.25) {
            self.rootView.bottomBar.layoutChain.bottom(kSafeBottomMargin + 20 + offset)
        }
//        completion: { _ in
//            let offset: CGFloat = self.rootView.tableView.contentSize.height
//            self.rootView.tableView.setContentOffset(CGPointMake(0, offset), animated: false)
//        }
        scrollToBottom()
        
        if show {
            self.rootView.textField.resignFirstResponder()
            EmojiPanelCell.preloadAnimations()
        }
    }
    
    // MARK: - 显示相册
    private func showAlbum() {
        // 设置与微信主题一致的配置
        let config = PhotoTools.getWXPickerConfig()
        // 最多可以选择的资源数，如果为0则不限制
        config.selectOptions = [.photo]
        config.selectMode = .multiple
        config.maximumSelectedCount = 9
//                config.maximumSelectedPhotoFileSize = 5242880
        config.allowSyncICloudWhenSelectPhoto = false
        config.previewView.bottomView.editButtonHidden = true
        config.photoList.allowAddCamera = true
        config.photoList.camera.allowsEditing = false
        let pickerController = PhotoPickerController(picker: config)
        pickerController.pickerDelegate = self
        pickerController.modalPresentationStyle = .fullScreen
        self.present(pickerController, animated: true, completion: nil)
    }

    // MARK: - Voice Recording
    private var audioRecorder: AVAudioRecorder?
    private var recordFileURL: URL?
    private var recordTimer: Timer?
    private var recordDuration: Int = 0
    private func setupVoiceRecording() {
        let longPress = UILongPressGestureRecognizer(target: self, action: #selector(handleVoiceLongPress(_:)))
        longPress.minimumPressDuration = 0.2
        rootView.voiceRecordView.speakBtn.addGestureRecognizer(longPress)
    }

    @objc private func handleVoiceLongPress(_ gesture: UILongPressGestureRecognizer) {
        let location = gesture.location(in: rootView.voiceRecordView)
        let btnCenterX = rootView.voiceRecordView.speakBtn.center.x
        let isCancel = location.x < btnCenterX - 100

        switch gesture.state {
        case .began:
            AudioServicesPlaySystemSound(1519)
            rootView.voiceRecordView.state = .recording
            startRecording()
        case .changed:
            let wasRecording = rootView.voiceRecordView.state == .recording
            rootView.voiceRecordView.state = isCancel ? .canceling : .recording
            rootView.voiceRecordView.cancelBtn.isSelected = isCancel
            if isCancel && wasRecording {
                AudioServicesPlaySystemSound(1519)
            }
        case .ended:
            stopRecording(cancel: isCancel)
        default:
            break
        }
    }

    private func startRecording() {
        let session = AVAudioSession.sharedInstance()
        try? session.setCategory(.playAndRecord, mode: .default)
        try? session.setActive(true)

        let dir = NSTemporaryDirectory()
        let filename = "voice_\(Int(Date().timeIntervalSince1970)).wav"
        recordFileURL = URL(fileURLWithPath: dir + filename)

        let settings: [String: Any] = [
            AVFormatIDKey: kAudioFormatLinearPCM,
            AVSampleRateKey: 8000,
            AVNumberOfChannelsKey: 1,
            AVLinearPCMBitDepthKey: 16,
            AVLinearPCMIsFloatKey: false
        ]

        guard let url = recordFileURL else { return }
        audioRecorder = try? AVAudioRecorder(url: url, settings: settings)
        audioRecorder?.record()

        recordDuration = 0
        recordTimer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { [weak self] _ in
            self?.recordDuration += 1
        }
    }

    private func stopRecording(cancel: Bool) {
        audioRecorder?.stop()
        recordTimer?.invalidate()
        recordTimer = nil
        rootView.voiceRecordView.stopRotating()
        
        try? AVAudioSession.sharedInstance().setActive(false)

        if cancel {
            self.rootView.voiceRecordView.cancelBtn.isSelected = false
            if let url = recordFileURL { try? FileManager.default.removeItem(at: url) }
            return
        }

        guard let url = recordFileURL, recordDuration >= 1 else {
            DLToast.show(text: "说话时间太短")
            if let url = recordFileURL { try? FileManager.default.removeItem(at: url) }
            return
        }

        // Send voice message via OpenIM
        let msg = OIMMessageInfo.createSoundMessage(fromFullPath: url.path, duration: recordDuration * 1000)
        OIMManager.manager.sendMessage(msg,
                                       recvID: "",
                                       groupID: viewModel.groupId,
                                       offlinePushInfo: nil,
                                       onSuccess: { [weak self] _ in
            self?.viewModel.onReceiveMessage(msg)
        },
                                       onProgress: nil as OIMNumberCallback?,
                                       onFailure: { code, errMsg in
            print("Voice send failed: \(code) \(errMsg ?? "")")
        })
    }

    // MARK: - API
    private func requestGroupInfoByKey() {
        GroupService.groupInfoByKey(viewModel.groupId).subscribe { response in
            guard let model = response.model else { return }
            self.viewModel.memberList = response.list
            self.rootView.groupNameLabel.text = model.name
            self.rootView.groupAvatarView.image = model.groupIcon
            self.viewModel.loadMessages()
        }.disposed(by: disposeBag)
    }
    
    // MARK: - dataSource
    private lazy var dataSource: RxTableViewSectionedReloadDataSource<ChatSectionModel> = {
        RxTableViewSectionedReloadDataSource<ChatSectionModel> { _, tableView, indexPath, item in
            switch item {
            case let .send(msg):
                let cell: TextSendMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                return cell
            case let .received(msg):
                let cell: TextReceivedMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                return cell
            case let .emojiSend(msg):
                let cell: EmojiSendMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                return cell
            case let .emojiReceived(msg):
                let cell: EmojiReceivedMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                return cell
            case let .voiceSend(msg):
                let cell: VoiceSendMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                return cell
            case let .voiceReceived(msg):
                let cell: VoiceReceivedMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                return cell
            case let .imageSend(msg):
                let cell: ImageSendMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                cell.onImageTap = { [weak self] in
                    self?.showBigImage(imgUrlList: [msg.imageUrl], currentPage: 0, projectiveView: cell.photoView)
                }
                return cell
            case let .imageReceived(msg):
                let cell: ImageReceivedMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(msg)
                cell.onImageTap = { [weak self] in
                    self?.showBigImage(imgUrlList: [msg.imageUrl], currentPage: 0, projectiveView: cell.photoView)
                }
                return cell
            case let .notification(text):
                let cell: NotificationMsgCell = tableView.dequeueReusableCell(for: indexPath)
                cell.configure(text)
                return cell
            }
        }
    }()
}

// MARK: - MessageListenerProxy
private class MessageListenerProxy: NSObject, OIMAdvancedMsgListener {
    private let handler: (OIMMessageInfo) -> Void

    init(handler: @escaping (OIMMessageInfo) -> Void) {
        self.handler = handler
    }

    func onRecvNewMessage(_ msg: OIMMessageInfo) {
        handler(msg)
    }
}

// MARK: - PhotoPickerControllerDelegate
extension GroupChatVC: PhotoPickerControllerDelegate {
    /// 选择完成之后调用
    /// - Parameters:
    ///   - pickerController: 对应的 PhotoPickerController
    ///   - result: 选择的结果
    ///     result.photoAssets  选择的资源数组
    ///     result.isOriginal   是否选中原图
    func pickerController(_ pickerController: PhotoPickerController,
                            didFinishSelection result: PickerResult) {
        result.getImage { (image, photoAsset, index) in
        } completionHandler: { [weak self] (images) in
            guard let self = self else { return }
            for img in images {
                self.sendImageMessage(img)
            }
        }
    }

    private func sendImageMessage(_ image: UIImage) {
        guard let data = image.jpegData(compressionQuality: 0.8) else { return }
        let dir = NSTemporaryDirectory()
        let filename = "img_\(Int(Date().timeIntervalSince1970)).jpg"
        let fileURL = URL(fileURLWithPath: dir + filename)
        try? data.write(to: fileURL)

        let displaySize = Self.imageDisplaySize(w: image.size.width, h: image.size.height)

        let msg = OIMMessageInfo.createImageMessage(fromFullPath: fileURL.path)
        // 使用 SDK 的 clientMsgID 作为本地消息 ID，方便后续与监听器去重
        let localId = msg.clientMsgID ?? UUID().uuidString

        // 立即显示本地图片（带 loading）
        let localMsg = ChatMessage(
            id: localId,
            isSelf: true,
            avatar: viewModel.getUserAvatar(id: AppContextManager.shared.userId),
            senderName: AppContextManager.shared.name,
            content: "",
            voiceUrl: "",
            imageUrl: fileURL.path,
            imageWidth: displaySize.width,
            imageHeight: displaySize.height,
            timestamp: Date().timeIntervalSince1970,
            showTime: false,
            isUploading: true
        )
        viewModel.appendLocalMessage(.imageSend(localMsg))
        OIMManager.manager.sendMessage(msg,
                                       recvID: "",
                                       groupID: viewModel.groupId,
                                       offlinePushInfo: nil,
                                       onSuccess: { [weak self] returnedMsg in
            // 服务端返回后，更新本地消息为服务端图片URL，去掉loading
            // 注意：returnedMsg 是 SDK 回填服务端数据后的新 OIMMessageInfo，包含完整 URL
            let networkUrl = returnedMsg?.pictureElem?.sourcePicture?.url
                ?? returnedMsg?.pictureElem?.bigPicture?.url
                ?? returnedMsg?.pictureElem?.sourcePath
                ?? ""
            self?.viewModel.updateLocalMessage(id: localId) { chatMsg in
                // 仅在服务端有URL时才替换，否则保留本地路径让图片仍可见
                if !networkUrl.isEmpty {
                    chatMsg.imageUrl = networkUrl
                }
                chatMsg.isUploading = false
            }
            try? FileManager.default.removeItem(at: fileURL)
        },
                                       onProgress: nil as OIMNumberCallback?,
                                       onFailure: { [weak self] code, errMsg in
            print("Image send failed: \(code) \(errMsg ?? "")")
            // 发送失败，隐藏 loading
            self?.viewModel.updateLocalMessage(id: localId) { chatMsg in
                chatMsg.isUploading = false
            }
        })
    }

    private static func imageDisplaySize(w: CGFloat, h: CGFloat) -> CGSize {
        guard w > 0, h > 0 else { return CGSize(width: 160, height: 160) }
        let maxW: CGFloat = 200, maxH: CGFloat = 250, minW: CGFloat = 80
        var dw = maxW, dh = dw * (h / w)
        if dh > maxH { dh = maxH; dw = dh * (w / h) }
        if dw < minW { dw = minW; dh = dw * (h / w) }
        return CGSize(width: dw, height: dh)
    }
    
    /// 点击取消时调用
    /// - Parameter pickerController: 对应的 PhotoPickerController
    func pickerController(didCancel pickerController: PhotoPickerController) {
        
    }
}