package com.mydocker.container;

import java.nio.file.Path;
import java.util.List;
import java.util.Map;
import java.util.UUID;

/**
 * Represents a container instance
 */
public class Container {
    private final String id;
    private final String name;
    private final ContainerConfig config;
    private ContainerState state;
    private int pid;
    private Path rootfs;
    
    public Container(ContainerConfig config) {
        this.id = UUID.randomUUID().toString().substring(0, 12);
        this.name = config.getName() != null ? config.getName() : "container_" + id.substring(0, 6);
        this.config = config;
        this.state = ContainerState.CREATED;
    }
    
    public String getId() { return id; }
    public String getName() { return name; }
    public ContainerConfig getConfig() { return config; }
    public ContainerState getState() { return state; }
    public int getPid() { return pid; }
    public Path getRootfs() { return rootfs; }
    
    public void setState(ContainerState state) { this.state = state; }
    public void setPid(int pid) { this.pid = pid; }
    public void setRootfs(Path rootfs) { this.rootfs = rootfs; }
}

/**
 * Container configuration
 */
class ContainerConfig {
    private String image;
    private String name;
    private List<String> command;
    private Map<String, String> env;
    private String hostname;
    private boolean tty;
    private boolean interactive;
    private ResourceLimits resources;
    private NetworkConfig network;
    private List<String> volumes;
    
    // Builder pattern for configuration
    public static class Builder {
        private ContainerConfig config = new ContainerConfig();
        
        public Builder image(String image) { config.image = image; return this; }
        public Builder name(String name) { config.name = name; return this; }
        public Builder command(List<String> cmd) { config.command = cmd; return this; }
        public Builder env(Map<String, String> env) { config.env = env; return this; }
        public Builder hostname(String hostname) { config.hostname = hostname; return this; }
        public Builder tty(boolean tty) { config.tty = tty; return this; }
        public Builder interactive(boolean i) { config.interactive = i; return this; }
        public Builder resources(ResourceLimits r) { config.resources = r; return this; }
        public Builder network(NetworkConfig n) { config.network = n; return this; }
        public Builder volumes(List<String> v) { config.volumes = v; return this; }
        
        public ContainerConfig build() { return config; }
    }
    
    public String getImage() { return image; }
    public String getName() { return name; }
    public List<String> getCommand() { return command; }
    public Map<String, String> getEnv() { return env; }
    public String getHostname() { return hostname; }
    public boolean isTty() { return tty; }
    public boolean isInteractive() { return interactive; }
    public ResourceLimits getResources() { return resources; }
    public NetworkConfig getNetwork() { return network; }
    public List<String> getVolumes() { return volumes; }
}

/**
 * Resource limits using cgroups
 */
class ResourceLimits {
    private long memoryLimit;      // bytes
    private long memorySwap;       // bytes
    private int cpuShares;         // relative weight
    private long cpuPeriod;        // microseconds
    private long cpuQuota;         // microseconds
    private int pidsLimit;         // max processes
    
    public long getMemoryLimit() { return memoryLimit; }
    public void setMemoryLimit(long limit) { this.memoryLimit = limit; }
    public int getCpuShares() { return cpuShares; }
    public void setCpuShares(int shares) { this.cpuShares = shares; }
    public long getCpuQuota() { return cpuQuota; }
    public void setCpuQuota(long quota) { this.cpuQuota = quota; }
    public int getPidsLimit() { return pidsLimit; }
    public void setPidsLimit(int limit) { this.pidsLimit = limit; }
}

/**
 * Network configuration
 */
class NetworkConfig {
    private String mode;           // bridge, host, none
    private List<String> ports;    // port mappings
    private String ipAddress;
    
    public String getMode() { return mode; }
    public void setMode(String mode) { this.mode = mode; }
    public List<String> getPorts() { return ports; }
    public String getIpAddress() { return ipAddress; }
}

/**
 * Container state
 */
enum ContainerState {
    CREATED,
    RUNNING,
    PAUSED,
    STOPPED,
    EXITED
}