/**
 * 云原生应用生命周期管理系统
 * 支持应用的部署、扩展、更新和销毁等生命周期操作
 */
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

public class CloudNativeLifecycleManager {
    // 应用实例存储
    private final Map<String, Application> applications;
    // 资源管理器
    private final ResourceManager resourceManager;
    // 事件监听器列表
    private final List<LifecycleEventListener> eventListeners;
    // 单例实例
    private static volatile CloudNativeLifecycleManager instance;
    
    // 生命周期事件监听器接口
    public interface LifecycleEventListener {
        void onApplicationCreated(Application app);
        void onApplicationDeployed(Application app);
        void onApplicationScaled(Application app, int oldReplicas, int newReplicas);
        void onApplicationUpdated(Application app, ApplicationConfig oldConfig);
        void onApplicationDestroyed(String appId);
    }
    
    // 应用配置类
    public static class ApplicationConfig {
        private String name;
        private String image;
        private int replicas;
        private Map<String, String> envVars;
        private Map<String, Integer> resources;
        private List<PortMapping> ports;
        
        public ApplicationConfig(String name, String image) {
            this.name = name;
            this.image = image;
            this.replicas = 1;
            this.envVars = new HashMap<>();
            this.resources = new HashMap<>();
            this.ports = new ArrayList<>();
        }
        
        // Getters and Setters
        public String getName() { return name; }
        public void setName(String name) { this.name = name; }
        public String getImage() { return image; }
        public void setImage(String image) { this.image = image; }
        public int getReplicas() { return replicas; }
        public void setReplicas(int replicas) { this.replicas = replicas; }
        public Map<String, String> getEnvVars() { return envVars; }
        public void setEnvVars(Map<String, String> envVars) { this.envVars = envVars; }
        public Map<String, Integer> getResources() { return resources; }
        public void setResources(Map<String, Integer> resources) { this.resources = resources; }
        public List<PortMapping> getPorts() { return ports; }
        public void setPorts(List<PortMapping> ports) { this.ports = ports; }
        
        @Override
        public String toString() {
            return "ApplicationConfig{name='" + name + "', image='" + image + "', replicas=" + replicas + "}";
        }
    }
    
    // 端口映射类
    public static class PortMapping {
        private int containerPort;
        private int hostPort;
        private String protocol;
        
        public PortMapping(int containerPort, int hostPort, String protocol) {
            this.containerPort = containerPort;
            this.hostPort = hostPort;
            this.protocol = protocol;
        }
        
        public int getContainerPort() { return containerPort; }
        public int getHostPort() { return hostPort; }
        public String getProtocol() { return protocol; }
        
        @Override
        public String toString() {
            return hostPort + ":" + containerPort + "/" + protocol;
        }
    }
    
    // 应用实例类
    public static class Application {
        private final String id;
        private ApplicationConfig config;
        private String status;
        private List<Pod> pods;
        private final Map<String, String> metadata;
        private final String createdAt;
        private String updatedAt;
        
        public Application(String id, ApplicationConfig config) {
            this.id = id;
            this.config = config;
            this.status = "PENDING";
            this.pods = new ArrayList<>();
            this.metadata = new HashMap<>();
            String timestamp = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
            this.createdAt = timestamp;
            this.updatedAt = timestamp;
        }
        
        // Getters and Setters
        public String getId() { return id; }
        public ApplicationConfig getConfig() { return config; }
        public void setConfig(ApplicationConfig config) { this.config = config; }
        public String getStatus() { return status; }
        public void setStatus(String status) { this.status = status; }
        public List<Pod> getPods() { return pods; }
        public void setPods(List<Pod> pods) { this.pods = pods; }
        public Map<String, String> getMetadata() { return metadata; }
        public String getCreatedAt() { return createdAt; }
        public String getUpdatedAt() { return updatedAt; }
        public void setUpdatedAt(String updatedAt) { this.updatedAt = updatedAt; }
    }
    
    // Pod类（容器组）
    public static class Pod {
        private final String id;
        private final String appId;
        private String nodeId;
        private String status;
        private final String createdAt;
        
        public Pod(String id, String appId) {
            this.id = id;
            this.appId = appId;
            this.status = "PENDING";
            this.createdAt = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
        }
        
        public String getId() { return id; }
        public String getAppId() { return appId; }
        public String getNodeId() { return nodeId; }
        public void setNodeId(String nodeId) { this.nodeId = nodeId; }
        public String getStatus() { return status; }
        public void setStatus(String status) { this.status = status; }
        public String getCreatedAt() { return createdAt; }
    }
    
    // 资源管理器
    private static class ResourceManager {
        private final Map<String, Integer> availableResources;
        
        public ResourceManager() {
            this.availableResources = new HashMap<>();
            // 模拟初始资源
            availableResources.put("cpu", 16);
            availableResources.put("memory", 65536); // 64GB
            availableResources.put("disk", 1048576); // 1TB
        }
        
        public synchronized boolean allocateResources(Map<String, Integer> required) {
            // 检查资源是否足够
            for (Map.Entry<String, Integer> entry : required.entrySet()) {
                Integer available = availableResources.getOrDefault(entry.getKey(), 0);
                if (available < entry.getValue()) {
                    return false;
                }
            }
            
            // 分配资源
            for (Map.Entry<String, Integer> entry : required.entrySet()) {
                availableResources.put(entry.getKey(), 
                    availableResources.get(entry.getKey()) - entry.getValue());
            }
            
            return true;
        }
        
        public synchronized void releaseResources(Map<String, Integer> allocated) {
            for (Map.Entry<String, Integer> entry : allocated.entrySet()) {
                availableResources.put(entry.getKey(), 
                    availableResources.getOrDefault(entry.getKey(), 0) + entry.getValue());
            }
        }
        
        public Map<String, Integer> getAvailableResources() {
            return new HashMap<>(availableResources);
        }
    }
    
    private CloudNativeLifecycleManager() {
        this.applications = new ConcurrentHashMap<>();
        this.resourceManager = new ResourceManager();
        this.eventListeners = new ArrayList<>();
        System.out.println("云原生应用生命周期管理系统初始化完成");
    }
    
    // 获取单例实例
    public static CloudNativeLifecycleManager getInstance() {
        if (instance == null) {
            synchronized (CloudNativeLifecycleManager.class) {
                if (instance == null) {
                    instance = new CloudNativeLifecycleManager();
                }
            }
        }
        return instance;
    }
    
    // 注册事件监听器
    public void addEventListener(LifecycleEventListener listener) {
        if (listener != null && !eventListeners.contains(listener)) {
            eventListeners.add(listener);
        }
    }
    
    // 创建应用
    public Application createApplication(ApplicationConfig config) {
        String appId = "app-" + UUID.randomUUID().toString().substring(0, 8);
        Application app = new Application(appId, config);
        applications.put(appId, app);
        
        System.out.println("应用创建: " + appId + ", 配置: " + config);
        
        // 通知监听器
        for (LifecycleEventListener listener : eventListeners) {
            listener.onApplicationCreated(app);
        }
        
        return app;
    }
    
    // 部署应用
    public boolean deployApplication(String appId) {
        Application app = applications.get(appId);
        if (app == null) {
            System.err.println("应用不存在: " + appId);
            return false;
        }
        
        // 分配资源
        Map<String, Integer> resources = app.getConfig().getResources();
        if (!resourceManager.allocateResources(resources)) {
            System.err.println("资源不足，无法部署应用: " + appId);
            return false;
        }
        
        // 创建Pod实例
        List<Pod> pods = new ArrayList<>();
        for (int i = 0; i < app.getConfig().getReplicas(); i++) {
            String podId = "pod-" + UUID.randomUUID().toString().substring(0, 8);
            Pod pod = new Pod(podId, appId);
            pod.setNodeId("node-" + (i % 3 + 1)); // 模拟节点分配
            pod.setStatus("RUNNING");
            pods.add(pod);
            System.out.println("Pod创建: " + podId + " 应用: " + appId + " 节点: " + pod.getNodeId());
        }
        
        app.setPods(pods);
        app.setStatus("RUNNING");
        app.setUpdatedAt(LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        
        System.out.println("应用部署成功: " + appId + " 副本数: " + pods.size());
        
        // 通知监听器
        for (LifecycleEventListener listener : eventListeners) {
            listener.onApplicationDeployed(app);
        }
        
        return true;
    }
    
    // 扩展应用
    public boolean scaleApplication(String appId, int replicas) {
        Application app = applications.get(appId);
        if (app == null) {
            System.err.println("应用不存在: " + appId);
            return false;
        }
        
        if (replicas <= 0) {
            System.err.println("副本数必须大于0: " + replicas);
            return false;
        }
        
        int oldReplicas = app.getPods().size();
        if (oldReplicas == replicas) {
            System.out.println("应用已经是指定的副本数: " + appId + " replicas=" + replicas);
            return true;
        }
        
        if (replicas > oldReplicas) {
            // 扩容
            for (int i = oldReplicas; i < replicas; i++) {
                String podId = "pod-" + UUID.randomUUID().toString().substring(0, 8);
                Pod pod = new Pod(podId, appId);
                pod.setNodeId("node-" + (i % 3 + 1));
                pod.setStatus("RUNNING");
                app.getPods().add(pod);
                System.out.println("扩容Pod创建: " + podId + " 应用: " + appId);
            }
        } else {
            // 缩容
            List<Pod> pods = app.getPods();
            while (pods.size() > replicas) {
                Pod podToRemove = pods.remove(pods.size() - 1);
                System.out.println("缩容Pod删除: " + podToRemove.getId() + " 应用: " + appId);
            }
        }
        
        app.getConfig().setReplicas(replicas);
        app.setUpdatedAt(LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        
        System.out.println("应用扩展成功: " + appId + " 从 " + oldReplicas + " 到 " + replicas + " 副本");
        
        // 通知监听器
        for (LifecycleEventListener listener : eventListeners) {
            listener.onApplicationScaled(app, oldReplicas, replicas);
        }
        
        return true;
    }
    
    // 更新应用配置
    public boolean updateApplication(String appId, ApplicationConfig newConfig) {
        Application app = applications.get(appId);
        if (app == null) {
            System.err.println("应用不存在: " + appId);
            return false;
        }
        
        ApplicationConfig oldConfig = app.getConfig();
        
        // 保存旧配置的副本
        ApplicationConfig oldConfigCopy = new ApplicationConfig(oldConfig.getName(), oldConfig.getImage());
        oldConfigCopy.setReplicas(oldConfig.getReplicas());
        oldConfigCopy.setEnvVars(new HashMap<>(oldConfig.getEnvVars()));
        oldConfigCopy.setResources(new HashMap<>(oldConfig.getResources()));
        oldConfigCopy.setPorts(new ArrayList<>(oldConfig.getPorts()));
        
        // 更新配置
        app.setConfig(newConfig);
        app.setUpdatedAt(LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        
        // 如果副本数改变，重新调度
        if (newConfig.getReplicas() != oldConfig.getReplicas()) {
            scaleApplication(appId, newConfig.getReplicas());
        }
        
        System.out.println("应用更新成功: " + appId + " 配置从 " + oldConfig + " 更新到 " + newConfig);
        
        // 通知监听器
        for (LifecycleEventListener listener : eventListeners) {
            listener.onApplicationUpdated(app, oldConfigCopy);
        }
        
        return true;
    }
    
    // 销毁应用
    public boolean destroyApplication(String appId) {
        Application app = applications.remove(appId);
        if (app == null) {
            System.err.println("应用不存在: " + appId);
            return false;
        }
        
        // 释放资源
        resourceManager.releaseResources(app.getConfig().getResources());
        
        // 删除所有Pod
        System.out.println("销毁应用: " + appId + " 删除Pod数: " + app.getPods().size());
        
        // 通知监听器
        for (LifecycleEventListener listener : eventListeners) {
            listener.onApplicationDestroyed(appId);
        }
        
        return true;
    }
    
    // 获取应用列表
    public List<Application> getApplications() {
        return new ArrayList<>(applications.values());
    }
    
    // 获取应用详情
    public Application getApplication(String appId) {
        return applications.get(appId);
    }
    
    // 获取系统资源状态
    public Map<String, Integer> getResourceStatus() {
        return resourceManager.getAvailableResources();
    }
}