package com.ruoyi.device.bts;

import java.io.IOException;
import java.io.StringReader;
import java.math.BigDecimal;
import java.time.Instant;
import java.util.ArrayList;
import java.util.List;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamReader;
import com.ruoyi.device.model.DeviceWorkStatus;
import com.ruoyi.device.simulator.BtsSimulatorStateStore;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.ChannelState;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.ChannelTombstone;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.CollectorChannelState;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.CollectorHistoryAppend;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.CollectorHistoryFaults;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.CollectorMeasurementRecord;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.CollectorMetricState;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.CollectorRealtimeMeasurement;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.CollectorState;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.DeviceState;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.BtsDeviceProfile;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.RecentRequest;
import com.ruoyi.device.simulator.BtsSimulatorStateStore.SimulatorState;
import com.ruoyi.device.simulator.InMemoryBtsSimulatorStateStore;
import com.ruoyi.device.simulator.DevelopmentCollectorSimulation;
import com.ruoyi.device.simulator.DevelopmentCollectorSimulation.CollectorAdvance;
import com.ruoyi.device.simulator.DevelopmentCollectorSimulation.CollectorHistoryPage;
import com.ruoyi.device.simulator.DevelopmentCollectorSimulation.CollectorRealtimeSnapshot;

/** 提供由开发后端托管的临时只读 BTS 模拟端点。 */
public final class BtsDevelopmentSimulator implements AutoCloseable
{
    public static final String HOST = "127.0.0.1";
    public static final int DEFAULT_PORT = 15020;
    public static final String ADAPTER_CODE = "dev-sim";
    public static final String ADAPTER_NAME = "dev-sim BTS 模拟器";
    public static final int POLL_INTERVAL_MS = 5000;
    public static final String NEWARE_CT_4008T_5V6A_S1_F = "CT-4008T-5V6A-S1-F";
    public static final String NEWARE_CT_4008TN_5V12A_S1_F = "CT-4008Tn-5V12A-S1-F";

    private static final int MAX_CHANNEL_COUNT = 99;
    private static final int MAX_RECENT_REQUESTS = 20;
    private static final int TOMBSTONE_DISCOVERY_COUNT = 3;

    private final ScriptedBtsTcpSimulator simulator;
    private final BtsSimulatorStateStore stateStore;
    private SimulatorState state;
    private boolean running = true;
    private long observationSequence;

    /** 启动仅监听 IPv4 本机回环地址的开发模拟器；传入 0 时由系统分配测试端口。 */
    public BtsDevelopmentSimulator(int port) throws IOException
    {
        this(port, new InMemoryBtsSimulatorStateStore());
    }

    /** 从长期状态恢复后再启动 TCP 服务，避免服务先暴露默认拓扑。 */
    public BtsDevelopmentSimulator(int port, BtsSimulatorStateStore stateStore) throws IOException
    {
        this.stateStore = stateStore;
        state = stateStore.loadOrInitialize(defaultState());
        validateRestoredState();
        stateStore.completeValidatedRestore(state);
        simulator = ScriptedBtsTcpSimulator.responding(port, this::respond);
    }

    public int port()
    {
        return simulator.port();
    }

    /** 新增一台具有独立虚拟 IP 和通道数的开发设备。 */
    public synchronized int addDevice(String ip, int channelCount)
    {
        validateDeviceConfiguration(ip, channelCount, null);
        int deviceId = state.nextDeviceId();
        List<DeviceState> devices = new ArrayList<>(state.devices());
        devices.add(newDevice(deviceId, ip, BtsDeviceProfile.virtual(channelCount)));
        persist(new SimulatorState(BtsSimulatorStateStore.CURRENT_VERSION, devices, state.collectors(),
                deviceId + 1, state.nextCollectorId(), state.tombstones()));
        return deviceId;
    }

    /** 修改开发设备的虚拟地址、通道数和在线状态。 */
    public synchronized void updateDevice(int deviceId, String ip, int channelCount, boolean online)
    {
        DeviceState current = requireDevice(deviceId);
        validateDeviceConfiguration(ip, channelCount, deviceId);
        List<ChannelState> channels = new ArrayList<>(channelCount);
        for (int channelId = 1; channelId <= channelCount; channelId++)
        {
            channels.add(channelId <= current.channels().size()
                    ? current.channels().get(channelId - 1)
                    : new ChannelState(channelId, true, DeviceWorkStatus.STOPPED));
        }
        List<DeviceState> devices = replaceDevice(new DeviceState(deviceId, ip.trim(), online, channels,
                resizeProfile(current.profile(), channelCount)));
        List<ChannelTombstone> tombstones = new ArrayList<>(state.tombstones());
        for (int channelId = channelCount + 1; channelId <= current.channels().size(); channelId++)
            upsertTombstone(tombstones, current.deviceId(), current.ip(), channelId);
        tombstones.removeIf(item -> item.deviceId() == deviceId && item.channelId() <= channelCount);
        persist(new SimulatorState(state.version(), devices, state.collectors(), state.nextDeviceId(),
                state.nextCollectorId(), tombstones));
    }

    /** 使用现场确认的新威检测柜 profile 新增设备，型号之外的控制语义仍保持只读。 */
    public synchronized int addNewareDevice(String ip, String model)
    {
        BtsDeviceProfile profile = newareProfile(model);
        validateDeviceConfiguration(ip, profile.channelCount(), null);
        int deviceId = state.nextDeviceId();
        List<DeviceState> devices = new ArrayList<>(state.devices());
        devices.add(newDevice(deviceId, ip, profile));
        persist(new SimulatorState(state.version(), devices, state.collectors(), deviceId + 1,
                state.nextCollectorId(), state.tombstones()));
        return deviceId;
    }

    /** 将已有模拟设备切换为新威 profile，并按 profile 通道数调整拓扑。 */
    public synchronized void configureNewareProfile(int deviceId, String model)
    {
        DeviceState current = requireDevice(deviceId);
        BtsDeviceProfile profile = newareProfile(model);
        updateDeviceWithProfile(current, profile);
    }

    /** 删除指定开发设备；后续发现响应不再返回它。 */
    public synchronized void deleteDevice(int deviceId)
    {
        DeviceState removed = requireDevice(deviceId);
        List<DeviceState> devices = new ArrayList<>(state.devices());
        devices.removeIf(item -> item.deviceId() == deviceId);
        List<ChannelTombstone> tombstones = new ArrayList<>(state.tombstones());
        for (ChannelState channel : removed.channels())
            upsertTombstone(tombstones, removed.deviceId(), removed.ip(), channel.channelId());
        persist(new SimulatorState(state.version(), devices, state.collectors(), state.nextDeviceId(),
                state.nextCollectorId(), tombstones));
    }

    /** 修改指定开发设备的单个通道状态。 */
    public synchronized void updateChannel(int deviceId, int channelId, boolean online,
            DeviceWorkStatus workStatus)
    {
        requireControllableStatus(workStatus);
        DeviceState device = requireDevice(deviceId);
        if (channelId < 1 || channelId > device.channels().size())
            throw new IllegalArgumentException("channelId must be between 1 and " + device.channels().size());
        List<ChannelState> channels = new ArrayList<>(device.channels());
        channels.set(channelId - 1, new ChannelState(channelId, online, workStatus));
        persist(new SimulatorState(state.version(),
                replaceDevice(new DeviceState(deviceId, device.ip(), device.online(), channels, device.profile())), state.collectors(),
                state.nextDeviceId(), state.nextCollectorId(), state.tombstones()));
    }

    /** 新增一台与 BTS 检测柜拓扑隔离的开发采集器。 */
    public synchronized int addCollector(String ip, int channelCount)
    {
        validateCollectorConfiguration(ip, channelCount, null);
        int collectorId = state.nextCollectorId();
        List<CollectorState> collectors = new ArrayList<>(state.collectors());
        collectors.add(newCollector(collectorId, ip, channelCount));
        persist(new SimulatorState(state.version(), state.devices(), collectors, state.nextDeviceId(),
                collectorId + 1, state.tombstones()));
        return collectorId;
    }

    /** 修改开发采集器的虚拟地址、通道数和在线状态。 */
    public synchronized void updateCollector(int collectorId, String ip, int channelCount, boolean online)
    {
        validateCollectorConfiguration(ip, channelCount, collectorId);
        CollectorState current = requireCollector(collectorId);
        List<CollectorState> collectors = new ArrayList<>(state.collectors());
        collectors.replaceAll(item -> item.collectorId() == collectorId
                ? DevelopmentCollectorSimulation.resize(current, ip, channelCount, online, Instant.now())
                : item);
        persist(new SimulatorState(state.version(), state.devices(), collectors, state.nextDeviceId(),
                state.nextCollectorId(), state.tombstones()));
    }

    /** 删除指定开发采集器，不影响检测柜 TCP 发现结果。 */
    public synchronized void deleteCollector(int collectorId)
    {
        CollectorState collector = requireCollector(collectorId);
        List<CollectorState> collectors = new ArrayList<>(state.collectors());
        collectors.removeIf(item -> item.collectorId() == collectorId);
        SimulatorState next = new SimulatorState(state.version(), state.devices(), collectors, state.nextDeviceId(),
                state.nextCollectorId(), state.tombstones());
        stateStore.saveAndDeleteCollectorHistory(next, collector.deviceCode());
        this.state = next;
    }

    /** 配置采集器独立采样频率和历史下载故障场景。 */
    public synchronized void configureCollectorSampling(int collectorId, int sampleIntervalMs,
            CollectorHistoryFaults historyFaults)
    {
        CollectorState current = requireCollector(collectorId);
        replaceCollector(DevelopmentCollectorSimulation.configureSampling(current, sampleIntervalMs, historyFaults));
    }

    /** 配置一个稳定 S 通道的固定或动态演示指标。 */
    public synchronized void configureCollectorChannel(int collectorId, String channelCode,
            List<CollectorMetricState> metrics)
    {
        CollectorState current = requireCollector(collectorId);
        replaceCollector(DevelopmentCollectorSimulation.configureChannel(current, channelCode, metrics));
    }

    /**
     * 模拟现场人工统一开关机：关机停止采样但保留历史，开机后检测柜通道保持待机。
     * 该操作只改变模拟设备事实，不代表系统具备真实设备控制能力。
     */
    public synchronized void setAllDevicesPoweredOn(boolean poweredOn)
    {
        List<DeviceState> devices = state.devices().stream()
                .map(device -> new DeviceState(device.deviceId(), device.ip(), poweredOn,
                        device.channels().stream()
                                .map(channel -> new ChannelState(channel.channelId(), poweredOn,
                                        DeviceWorkStatus.STOPPED))
                                .toList(), device.profile()))
                .toList();
        Instant changedAt = Instant.now();
        List<CollectorState> collectors = state.collectors().stream()
                .map(collector -> DevelopmentCollectorSimulation.resize(collector, collector.ip(),
                        collector.channelCount(), poweredOn, changedAt))
                .toList();
        persist(new SimulatorState(state.version(), devices, collectors, state.nextDeviceId(),
                state.nextCollectorId(), state.tombstones()));
    }

    /** 按每台采集器自己的频率推进实时和历史采样。 */
    public synchronized void advanceCollectors(Instant now)
    {
        boolean hasOnlineCollector = false;
        for (CollectorState collector : state.collectors())
        {
            if (!collector.online()) continue;
            hasOnlineCollector = true;
            break;
        }
        if (!hasOnlineCollector) return;
        List<CollectorState> collectors = new ArrayList<>(state.collectors().size());
        List<CollectorHistoryAppend> historyAppends = new ArrayList<>();
        for (CollectorState collector : state.collectors())
        {
            CollectorAdvance advance = DevelopmentCollectorSimulation.advance(collector, now);
            collectors.add(advance.state());
            if (!advance.appendedRecords().isEmpty())
                historyAppends.add(new CollectorHistoryAppend(collector.deviceCode(), advance.appendedRecords()));
        }
        if (!historyAppends.isEmpty())
            persist(new SimulatorState(state.version(), state.devices(), collectors, state.nextDeviceId(),
                    state.nextCollectorId(), state.tombstones()), historyAppends);
    }

    /** 返回采集器最新实时快照；快照与分页历史保持不同读取路径。 */
    public synchronized CollectorRealtimeSnapshot collectorRealtime(int collectorId)
    {
        return DevelopmentCollectorSimulation.realtime(requireCollector(collectorId));
    }

    /** 分页下载采集器模拟历史，并应用已配置的重复、冲突、乱序或缺失场景。 */
    public synchronized CollectorHistoryPage collectorHistory(int collectorId, long offset, int limit)
    {
        CollectorState collector = requireCollector(collectorId);
        return DevelopmentCollectorSimulation.history(collector, stateStore, offset, limit);
    }

    /** 返回控制页需要的运行状态快照。 */
    public synchronized StateSnapshot snapshot()
    {
        List<DeviceSnapshot> deviceSnapshots = state.devices().stream()
                .map(device -> new DeviceSnapshot(device.deviceId(), device.ip(), device.online(), device.profile(),
                        device.channels().stream()
                                .map(channel -> new ChannelSnapshot(channel.channelId(), channel.online(),
                                        channel.workStatus()))
                                .toList()))
                .toList();
        List<CollectorSnapshot> collectorSnapshots = state.collectors().stream()
                .map(collector -> new CollectorSnapshot(collector.collectorId(), collector.deviceCode(),
                        collector.ip(), collector.mac(), collector.name(), collector.manufacturer(),
                        collector.model(), collector.channelCount(), collector.online(), collector.sampleIntervalMs(),
                        collector.channels(), collector.historyFaults(), collector.historyRecordCount(),
                        DevelopmentCollectorSimulation.realtime(collector).measurements()))
                .toList();
        return new StateSnapshot(running, HOST + ":" + port(), deviceSnapshots, collectorSnapshots,
                stateStore.loadRecentRequests());
    }

    /** 人工恢复默认拓扑；这是正常运行中唯一清空长期模拟状态的入口。 */
    public synchronized void reset()
    {
        SimulatorState defaultState = defaultState();
        stateStore.reset(defaultState);
        state = defaultState;
    }

    private SimulatorState defaultState()
    {
        return new SimulatorState(BtsSimulatorStateStore.CURRENT_VERSION,
                List.of(newDevice(1, "127.0.0.2", 4)),
                List.of(newCollector(1, "127.0.1.2", 4)), 2, 2, List.of());
    }

    private DeviceState newDevice(int deviceId, String ip, int channelCount)
    {
        return newDevice(deviceId, ip, BtsDeviceProfile.virtual(channelCount));
    }

    private DeviceState newDevice(int deviceId, String ip, BtsDeviceProfile profile)
    {
        List<ChannelState> channels = new ArrayList<>(profile.channelCount());
        for (int channelId = 1; channelId <= profile.channelCount(); channelId++)
            channels.add(new ChannelState(channelId, true, DeviceWorkStatus.STOPPED));
        return new DeviceState(deviceId, ip.trim(), true, channels, profile);
    }

    private CollectorState newCollector(int collectorId, String ip, int channelCount)
    {
        return new CollectorState(collectorId, "dev-sim-collector-" + collectorId,
                ip.trim(), simulatorCollectorMac(collectorId), "dev-sim 采集器 " + collectorId,
                "开发模拟器", "Virtual Collector", channelCount, true);
    }

    private void replaceCollector(CollectorState replacement)
    {
        List<CollectorState> collectors = new ArrayList<>(state.collectors());
        collectors.replaceAll(item -> item.collectorId() == replacement.collectorId() ? replacement : item);
        persist(new SimulatorState(state.version(), state.devices(), collectors, state.nextDeviceId(),
                state.nextCollectorId(), state.tombstones()));
    }

    private String respond(String request)
    {
        String command = readCommand(request);
        recordRequest(command, request);
        return switch (command)
        {
            case "getdevinfo" -> deviceInfoResponse();
            case "inquire" -> observationResponse(request);
            default -> "<bts version=\"1.0\"><cmd>error</cmd></bts>";
        };
    }

    private synchronized void recordRequest(String command, String request)
    {
        List<RecentRequest> recentRequests = new ArrayList<>(stateStore.loadRecentRequests());
        recentRequests.add(0, new RecentRequest(Instant.now(), command, request));
        if (recentRequests.size() > MAX_RECENT_REQUESTS)
            recentRequests = new ArrayList<>(recentRequests.subList(0, MAX_RECENT_REQUESTS));
        stateStore.saveRecentRequests(recentRequests);
    }

    private String readCommand(String request)
    {
        try
        {
            XMLInputFactory factory = XMLInputFactory.newFactory();
            factory.setProperty(XMLInputFactory.SUPPORT_DTD, false);
            factory.setProperty("javax.xml.stream.isSupportingExternalEntities", false);
            XMLStreamReader reader = factory.createXMLStreamReader(new StringReader(request));
            while (reader.hasNext())
            {
                if (reader.next() == XMLStreamConstants.START_ELEMENT && "cmd".equals(reader.getLocalName()))
                    return reader.getElementText().trim();
            }
        }
        catch (Exception exception)
        {
            throw new IllegalArgumentException("Invalid BTS request XML", exception);
        }
        throw new IllegalArgumentException("BTS request does not contain cmd");
    }

    private synchronized String deviceInfoResponse()
    {
        int channelCount = state.devices().stream().mapToInt(device -> device.channels().size()).sum()
                + state.tombstones().size();
        StringBuilder response = new StringBuilder("<bts version=\"1.0\"><cmd>getdevinfo_resp</cmd>")
                .append("<serverip count=\"0\"/><middle count=\"").append(channelCount).append("\">");
        for (DeviceState device : state.devices())
        {
            for (ChannelState channel : device.channels())
            {
                boolean available = device.online() && channel.online();
                appendDiscoveredChannel(response, device.deviceId(), device.ip(), channel.channelId(), available);
            }
        }
        List<ChannelTombstone> remaining = new ArrayList<>();
        for (ChannelTombstone tombstone : state.tombstones())
        {
            appendDiscoveredChannel(response, tombstone.deviceId(), tombstone.ip(), tombstone.channelId(), false);
            if (tombstone.remainingDiscoveries() > 1)
                remaining.add(new ChannelTombstone(tombstone.deviceId(), tombstone.ip(), tombstone.channelId(),
                        tombstone.remainingDiscoveries() - 1));
        }
        if (!remaining.equals(state.tombstones()))
            persist(new SimulatorState(state.version(), state.devices(), state.collectors(), state.nextDeviceId(),
                    state.nextCollectorId(), remaining));
        return response.append("</middle></bts>").toString();
    }

    private void appendDiscoveredChannel(StringBuilder response, int deviceId, String ip, int channelId,
            boolean available)
    {
        // 展示元数据是开发模拟器扩展，不代表真实 BTS 协议必然提供这些属性。
        DeviceState device = state.devices().stream().filter(item -> item.deviceId() == deviceId).findFirst().orElse(null);
        BtsDeviceProfile profile = device == null ? BtsDeviceProfile.virtual(channelId) : profileFor(device);
        response.append("<channel ip=\"").append(ip).append("\" devtype=\"").append(profile.devtype())
                .append("\" devid=\"").append(deviceId).append("\" subdevid=\"").append(profile.subDeviceId())
                .append("\" Channelid=\"").append(channelId).append("\" name=\"").append(profile.name())
                .append("\" manufacturer=\"").append(profile.manufacturer()).append("\" model=\"")
                .append(profile.model()).append("\" serialNumber=\"").append(profile.serialNumber())
                .append("\" firmwareVersion=\"").append(profile.firmwareVersion()).append("\" mac=\"")
                .append(simulatorMac(profile.devtype(), deviceId)).append("\">")
                .append(available).append("</channel>");
    }

    private synchronized String observationResponse(String request)
    {
        long tick = ++observationSequence;
        java.util.Set<String> requested = requestedChannels(request);
        List<ObservedChannel> available = new ArrayList<>();
        for (DeviceState device : state.devices())
            for (ChannelState channel : device.channels())
                if (device.online() && channel.online()
                        && (requested.isEmpty() || requested.contains(device.deviceId() + ":" + channel.channelId())))
                    available.add(new ObservedChannel(device.deviceId(), channel));

        StringBuilder response = new StringBuilder("<bts version=\"1.0\"><cmd>inquire_resp</cmd><list count=\"")
                .append(available.size()).append("\">");
        for (ObservedChannel observed : available)
        {
            ChannelState channel = observed.channel();
            DeviceState device = requireDevice(observed.deviceId());
            BtsDeviceProfile profile = profileFor(device);
            boolean working = channel.workStatus() == DeviceWorkStatus.WORKING;
            double wave = Math.sin((tick + channel.channelId()) * 0.7d);
            double current = working ? clamp(profile.currentMaxA().doubleValue() * (0.18d + wave * 0.02d),
                    profile.currentMinA().doubleValue(), profile.currentMaxA().doubleValue()) : 0d;
            double voltage = clamp(3.7d + wave * 0.01d, profile.voltageMinV().doubleValue(),
                    profile.voltageMaxV().doubleValue());
            double capacity = working ? Math.max(0d, tick * 0.001d * current) : 0d;
            double energy = capacity * voltage;
            response.append("<inquire dev=\"").append(profile.devtype()).append('-').append(observed.deviceId())
                    .append('-').append(profile.subDeviceId()).append('-').append(channel.channelId())
                    .append("-0\" cycle_id=\"1\" step_id=\"1\" step_type=\"cc\" workstatus=\"")
                    .append(toBtsWorkStatus(channel.workStatus()))
                    .append("\" current=\"").append(decimal(current)).append("\" voltage=\"")
                    .append(decimal(voltage)).append("\" capacity=\"").append(decimal(capacity))
                    .append("\" energy=\"").append(decimal(energy)).append("\" totaltime=\"")
                    .append(working ? tick : 0).append("\" relativetime=\"").append(working ? tick : 0)
                    .append("\" open_or_close=\"0\" log_code=\"0\"/>");
        }
        return response.append("</list></bts>").toString();
    }

    private java.util.Set<String> requestedChannels(String request)
    {
        java.util.Set<String> channels = new java.util.HashSet<>();
        try
        {
            XMLInputFactory factory = XMLInputFactory.newFactory();
            factory.setProperty(XMLInputFactory.SUPPORT_DTD, false);
            factory.setProperty("javax.xml.stream.isSupportingExternalEntities", false);
            XMLStreamReader reader = factory.createXMLStreamReader(new StringReader(request));
            while (reader.hasNext())
            {
                if (reader.next() == XMLStreamConstants.START_ELEMENT && "inquire".equals(reader.getLocalName()))
                {
                    String devid = reader.getAttributeValue(null, "devid");
                    String chlid = reader.getAttributeValue(null, "chlid");
                    if (devid != null && chlid != null) channels.add(devid + ":" + chlid);
                }
            }
            return channels;
        }
        catch (Exception exception)
        {
            throw new IllegalArgumentException("Invalid BTS inquire XML", exception);
        }
    }

    private BtsDeviceProfile profileFor(DeviceState device)
    {
        return device.profile() == null ? BtsDeviceProfile.virtual(device.channels().size()) : device.profile();
    }

    private BtsDeviceProfile resizeProfile(BtsDeviceProfile profile, int channelCount)
    {
        return new BtsDeviceProfile(profile.devtype(), profile.subDeviceId(), profile.name(), profile.manufacturer(),
                profile.model(), profile.serialNumber(), profile.firmwareVersion(), channelCount,
                profile.currentMinA(), profile.currentMaxA(), profile.voltageMinV(), profile.voltageMaxV(),
                profile.sampleIntervalMs());
    }

    private void updateDeviceWithProfile(DeviceState current, BtsDeviceProfile profile)
    {
        int channelCount = profile.channelCount();
        List<ChannelState> channels = new ArrayList<>(channelCount);
        for (int channelId = 1; channelId <= channelCount; channelId++)
            channels.add(channelId <= current.channels().size() ? current.channels().get(channelId - 1)
                    : new ChannelState(channelId, true, DeviceWorkStatus.STOPPED));
        List<DeviceState> devices = replaceDevice(new DeviceState(current.deviceId(), current.ip(), current.online(),
                channels, profile));
        List<ChannelTombstone> tombstones = new ArrayList<>(state.tombstones());
        for (int channelId = channelCount + 1; channelId <= current.channels().size(); channelId++)
            upsertTombstone(tombstones, current.deviceId(), current.ip(), channelId);
        tombstones.removeIf(item -> item.deviceId() == current.deviceId() && item.channelId() <= channelCount);
        persist(new SimulatorState(state.version(), devices, state.collectors(), state.nextDeviceId(),
                state.nextCollectorId(), tombstones));
    }

    private BtsDeviceProfile newareProfile(String model)
    {
        if (NEWARE_CT_4008T_5V6A_S1_F.equals(model))
            return new BtsDeviceProfile(22, 1, "新威 CT-4008T", "新威", model, "SIM-CT4008T-5V6A",
                    "BTS7.5.4", 8, new BigDecimal("-6.000"), new BigDecimal("6.000"), BigDecimal.ZERO,
                    new BigDecimal("5.000"), 100);
        if (NEWARE_CT_4008TN_5V12A_S1_F.equals(model))
            return new BtsDeviceProfile(22, 1, "新威 CT-4008Tn", "新威", model, "SIM-CT4008TN-5V12A",
                    "BTS8.0", 8, new BigDecimal("-12.000"), new BigDecimal("12.000"), BigDecimal.ZERO,
                    new BigDecimal("5.000"), 100);
        throw new IllegalArgumentException("Unsupported Neware simulator model: " + model);
    }

    private double clamp(double value, double minimum, double maximum)
    {
        return Math.max(minimum, Math.min(maximum, value));
    }

    private String decimal(double value)
    {
        return String.format(java.util.Locale.ROOT, "%.3f", value);
    }

    private String toBtsWorkStatus(DeviceWorkStatus status)
    {
        return switch (status)
        {
            case STOPPED -> "stop";
            case WORKING -> "working";
            case PAUSED -> "pause";
            case FINISHED -> "finish";
            default -> throw new IllegalArgumentException("Unsupported simulator work status: " + status);
        };
    }

    private void validateDeviceConfiguration(String ip, int channelCount, Integer currentDeviceId)
    {
        if (!isIpv4(ip)) throw new IllegalArgumentException("Simulator device IP must be a valid IPv4 address");
        if (channelCount < 1 || channelCount > MAX_CHANNEL_COUNT)
            throw new IllegalArgumentException("channelCount must be between 1 and " + MAX_CHANNEL_COUNT);
        boolean duplicate = state.devices().stream()
                .anyMatch(device -> device.ip().equals(ip.trim())
                        && device.deviceId() != (currentDeviceId == null ? -1 : currentDeviceId));
        duplicate = duplicate || state.collectors().stream().anyMatch(collector -> collector.ip().equals(ip.trim()));
        if (duplicate) throw new IllegalArgumentException("Simulator device IP must be unique");
    }

    private void validateCollectorConfiguration(String ip, int channelCount, Integer currentCollectorId)
    {
        if (!isIpv4(ip)) throw new IllegalArgumentException("Simulator collector IP must be a valid IPv4 address");
        if (channelCount < 1 || channelCount > MAX_CHANNEL_COUNT)
            throw new IllegalArgumentException("channelCount must be between 1 and " + MAX_CHANNEL_COUNT);
        boolean duplicate = state.collectors().stream()
                .anyMatch(collector -> collector.ip().equals(ip.trim())
                        && collector.collectorId() != (currentCollectorId == null ? -1 : currentCollectorId));
        duplicate = duplicate || state.devices().stream().anyMatch(device -> device.ip().equals(ip.trim()));
        if (duplicate) throw new IllegalArgumentException("Simulator collector IP must be unique");
    }

    private boolean isIpv4(String ip)
    {
        if (ip == null) return false;
        String[] parts = ip.trim().split("\\.", -1);
        if (parts.length != 4) return false;
        for (String part : parts)
        {
            try
            {
                int value = Integer.parseInt(part);
                if (part.isEmpty() || value < 0 || value > 255) return false;
            }
            catch (NumberFormatException exception)
            {
                return false;
            }
        }
        return true;
    }

    private DeviceState requireDevice(int deviceId)
    {
        return state.devices().stream().filter(item -> item.deviceId() == deviceId).findFirst()
                .orElseThrow(() -> new IllegalArgumentException("Unknown simulator device: " + deviceId));
    }

    private CollectorState requireCollector(int collectorId)
    {
        return state.collectors().stream().filter(item -> item.collectorId() == collectorId).findFirst()
                .orElseThrow(() -> new IllegalArgumentException("Unknown simulator collector: " + collectorId));
    }

    private List<DeviceState> replaceDevice(DeviceState replacement)
    {
        List<DeviceState> devices = new ArrayList<>(state.devices());
        devices.replaceAll(item -> item.deviceId() == replacement.deviceId() ? replacement : item);
        return devices;
    }

    private void upsertTombstone(List<ChannelTombstone> tombstones, int deviceId, String ip, int channelId)
    {
        tombstones.removeIf(item -> item.deviceId() == deviceId && item.channelId() == channelId);
        tombstones.add(new ChannelTombstone(deviceId, ip, channelId, TOMBSTONE_DISCOVERY_COUNT));
    }

    private void persist(SimulatorState nextState)
    {
        // 写穿失败时保留当前内存副本，避免控制页显示未持久化状态。
        stateStore.save(nextState);
        state = nextState;
    }

    private void persist(SimulatorState nextState, List<CollectorHistoryAppend> historyAppends)
    {
        // 主状态与原始历史批次必须一起成功，内存序号才能向前推进。
        stateStore.save(nextState, historyAppends);
        state = nextState;
    }

    private String simulatorMac(int devtype, int devid)
    {
        return String.format("02:44:%02X:%02X:%02X:%02X",
                (devtype >>> 8) & 0xFF, devtype & 0xFF, (devid >>> 8) & 0xFF, devid & 0xFF);
    }

    private String simulatorCollectorMac(int collectorId)
    {
        return String.format("02:43:00:00:%02X:%02X", (collectorId >>> 8) & 0xFF, collectorId & 0xFF);
    }

    private void requireControllableStatus(DeviceWorkStatus status)
    {
        if (status == null || (status != DeviceWorkStatus.STOPPED && status != DeviceWorkStatus.WORKING
                && status != DeviceWorkStatus.PAUSED && status != DeviceWorkStatus.FINISHED))
            throw new IllegalArgumentException("Simulator work status must be STOPPED, WORKING, PAUSED or FINISHED");
    }

    private void validateRestoredState()
    {
        java.util.Set<Integer> deviceIds = new java.util.HashSet<>();
        java.util.Set<Integer> collectorIds = new java.util.HashSet<>();
        java.util.Set<String> ips = new java.util.HashSet<>();
        int maximumDeviceId = 0;
        for (DeviceState device : state.devices())
        {
            if (device.deviceId() < 1 || !deviceIds.add(device.deviceId()) || !isIpv4(device.ip())
                    || !ips.add(device.ip()) || device.channels().isEmpty()
                    || device.channels().size() > MAX_CHANNEL_COUNT)
                throw new IllegalStateException("Invalid BTS simulator device state in Redis");
            if (profileFor(device).channelCount() != device.channels().size())
                throw new IllegalStateException("BTS simulator device profile channel count does not match topology");
            maximumDeviceId = Math.max(maximumDeviceId, device.deviceId());
            for (int index = 0; index < device.channels().size(); index++)
            {
                ChannelState channel = device.channels().get(index);
                if (channel.channelId() != index + 1)
                    throw new IllegalStateException("Invalid BTS simulator channel state in Redis");
                requireControllableStatus(channel.workStatus());
            }
        }
        int maximumCollectorId = 0;
        for (CollectorState collector : state.collectors())
        {
            if (collector.collectorId() < 1 || !collectorIds.add(collector.collectorId())
                    || !isIpv4(collector.ip()) || !ips.add(collector.ip())
                    || collector.channelCount() < 1 || collector.channelCount() > MAX_CHANNEL_COUNT)
                throw new IllegalStateException("Invalid BTS simulator collector state in Redis");
            DevelopmentCollectorSimulation.validate(collector, stateStore);
            maximumCollectorId = Math.max(maximumCollectorId, collector.collectorId());
        }
        java.util.Set<String> tombstoneIds = new java.util.HashSet<>();
        boolean invalidTombstone = state.tombstones().stream().anyMatch(item -> item.deviceId() < 1
                || !isIpv4(item.ip()) || item.channelId() < 1 || item.channelId() > MAX_CHANNEL_COUNT
                || item.remainingDiscoveries() < 1 || item.remainingDiscoveries() > TOMBSTONE_DISCOVERY_COUNT
                || !tombstoneIds.add(item.deviceId() + ":" + item.channelId()));
        if (state.nextDeviceId() <= maximumDeviceId || state.nextCollectorId() <= maximumCollectorId
                || invalidTombstone)
            throw new IllegalStateException("Invalid BTS simulator numbering or tombstone state in Redis");
    }

    @Override
    public synchronized void close() throws Exception
    {
        running = false;
        simulator.close();
    }

    private record ObservedChannel(int deviceId, ChannelState channel) { }

    public record StateSnapshot(boolean running, String listenAddress, List<DeviceSnapshot> devices,
            List<CollectorSnapshot> collectors, List<RecentRequest> recentRequests) { }

    public record DeviceSnapshot(int deviceId, String ip, boolean online, BtsDeviceProfile profile,
            List<ChannelSnapshot> channels) { }

    public record ChannelSnapshot(int channelId, boolean online, DeviceWorkStatus workStatus) { }

    public record CollectorSnapshot(int collectorId, String deviceCode, String ip, String mac, String name,
            String manufacturer, String model, int channelCount, boolean online, int sampleIntervalMs,
            List<CollectorChannelState> channels, CollectorHistoryFaults historyFaults, long historyRecordCount,
            List<CollectorRealtimeMeasurement> latestMeasurements)
    {
        public CollectorSnapshot
        {
            channels = List.copyOf(channels);
            latestMeasurements = List.copyOf(latestMeasurements);
        }
    }

}