Servers/MoonlightServers.Daemon/ServerSystem/Implementations/Docker/ContainerConfigMapper.cs

using Docker.DotNet.Models;
using MoonlightServers.Daemon.Models;

namespace MoonlightServers.Daemon.ServerSystem.Implementations.Docker;

public class ContainerConfigMapper
{
    public CreateContainerParameters GetRuntimeConfig(
        string uuid,
        string name,
        RuntimeConfiguration configuration,
        string runtimeStoragePath
    )
    {
        var parameters = new CreateContainerParameters()
        {
            HostConfig = new()
        };

        ApplySharedOptions(parameters, configuration);

        // Limits

        if (configuration.Limits.CpuPercent.HasValue)
        {
            parameters.HostConfig.CPUQuota = configuration.Limits.CpuPercent.Value * 1000;
            parameters.HostConfig.CPUPeriod = 100000;
            parameters.HostConfig.CPUShares = 1024;
        }

        if (configuration.Limits.MemoryMb.HasValue)
        {
            var memoryLimit = configuration.Limits.MemoryMb.Value;

            // The overhead multiplier gives the container a little bit more memory to prevent crashes
            var memoryOverhead = memoryLimit + memoryLimit * 0.05f;

            parameters.HostConfig.Memory = (long)memoryOverhead * 1024L * 1024L;
            parameters.HostConfig.MemoryReservation = (long)memoryLimit * 1024L * 1024L;

            if (configuration.Limits.SwapMb.HasValue)
            {
                var rawSwap = configuration.Limits.SwapMb.Value * 1024L * 1024L;
                parameters.HostConfig.MemorySwap = rawSwap + (long)memoryOverhead;
            }
        }

        parameters.HostConfig.BlkioWeight = 100;
        parameters.HostConfig.OomKillDisable = true;

        // Storage

        parameters.HostConfig.Tmpfs = new Dictionary<string, string>()
        {
            { "/tmp", "rw,exec,nosuid,size=100M" } // TODO: Config
        };

        parameters.WorkingDir = "/home/container";

        parameters.HostConfig.Mounts = new List<Mount>();
        parameters.HostConfig.Mounts.Add(new Mount()
        {
            Source = runtimeStoragePath,
            Target = "/home/container",
            Type = "bind",
            ReadOnly = false
        });

        // Labels
        parameters.Labels = new Dictionary<string, string>()
        {
            { "dev.moonlightpanel", "true" },
            { "dev.moonlightpanel.id", uuid }
        };

        foreach (var label in configuration.Environment.Labels)
            parameters.Labels.Add(label.Key, label.Value);

        // Security

        parameters.HostConfig.CapDrop = new List<string>()
        {
            "setpcap", "mknod", "audit_write", "net_raw", "dac_override",
            "fowner", "fsetid", "net_bind_service", "sys_chroot", "setfcap"
        };

        parameters.HostConfig.ReadonlyRootfs = true;
        parameters.HostConfig.SecurityOpt = new List<string>()
        {
            "no-new-privileges"
        };

        // Name

        parameters.Name = name;

        // Docker Image
        parameters.Image = configuration.Template.DockerImage;

        // Networking

        if (configuration.Network.Ports.Length > 0 && !string.IsNullOrWhiteSpace(configuration.Network.FriendlyName))
            parameters.Hostname = configuration.Network.FriendlyName;

        parameters.ExposedPorts = new Dictionary<string, EmptyStruct>();
        parameters.HostConfig.PortBindings = new Dictionary<string, IList<PortBinding>>();

        foreach (var port in configuration.Network.Ports)
        {
            parameters.ExposedPorts.Add($"{port.Port}/tcp", new());
            parameters.ExposedPorts.Add($"{port.Port}/udp", new());

            parameters.HostConfig.PortBindings.Add($"{port.Port}/tcp", new List<PortBinding>
            {
                new()
                {
                    HostPort = port.Port.ToString(),
                    HostIP = port.IpAddress
                }
            });

            parameters.HostConfig.PortBindings.Add($"{port.Port}/udp", new List<PortBinding>
            {
                new()
                {
                    HostPort = port.Port.ToString(),
                    HostIP = port.IpAddress
                }
            });
        }

        // TODO: Force outgoing ip stuff

        // User
        parameters.User = "1000:1000";

        return parameters;
    }

    public CreateContainerParameters GetInstallConfig(
        string uuid,
        string name,
        RuntimeConfiguration runtimeConfiguration,
        InstallConfiguration installConfiguration,
        string runtimeStoragePath,
        string installStoragePath
    )
    {
        var parameters = new CreateContainerParameters()
        {
            HostConfig = new()
        };

        ApplySharedOptions(parameters, runtimeConfiguration);

        // Labels
        parameters.Labels = new Dictionary<string, string>()
        {
            { "dev.moonlightpanel", "true" },
            { "dev.moonlightpanel.id", uuid }
        };

        foreach (var label in runtimeConfiguration.Environment.Labels)
            parameters.Labels.Add(label.Key, label.Value);

        // Name

        parameters.Name = name;

        // Docker Image
        parameters.Image = installConfiguration.DockerImage;

        // User
        parameters.User = "1000:1000";

        // Storage
        parameters.WorkingDir = "/mnt/server";

        parameters.HostConfig.Mounts = new List<Mount>();

        parameters.HostConfig.Mounts.Add(new Mount()
        {
            Source = runtimeStoragePath,
            Target = "/mnt/server",
            ReadOnly = false,
            Type = "bind"
        });

        parameters.HostConfig.Mounts.Add(new Mount()
        {
            Source = installStoragePath,
            Target = "/mnt/install",
            ReadOnly = false,
            Type = "bind"
        });

        // Command
        parameters.Cmd = [installConfiguration.Shell, "/mnt/install/install.sh"];

        return parameters;
    }

    private void ApplySharedOptions(
        CreateContainerParameters parameters,
        RuntimeConfiguration configuration
    )
    {
        // Input, output & error streams and TTY

        parameters.Tty = true;
        parameters.AttachStderr = true;
        parameters.AttachStdin = true;
        parameters.AttachStdout = true;
        parameters.OpenStdin = true;

        // Logging

        parameters.HostConfig.LogConfig = new()
        {
            Type = "json-file", // We need to use this provider, as the GetLogs endpoint needs it
            Config = new Dictionary<string, string>()
        };

        // Environment variables

        parameters.Env = new List<string>()
        {
            $"STARTUP={configuration.Template.StartupCommand}",
            //TODO: Add timezone, add server ip
        };

        if (configuration.Limits.MemoryMb.HasValue)
            parameters.Env.Add($"SERVER_MEMORY={configuration.Limits.MemoryMb.Value}");

        if (configuration.Network.MainPort != null)
        {
            parameters.Env.Add($"SERVER_IP={configuration.Network.MainPort.IpAddress}");
            parameters.Env.Add($"SERVER_PORT={configuration.Network.MainPort.Port}");
        }

        // Handle port variables
        var i = 1;
        foreach (var port in configuration.Network.Ports)
        {
            parameters.Env.Add($"ML_PORT_{i}={port.Port}");
            i++;
        }

        // Copy variables as env vars
        foreach (var variable in configuration.Environment.Variables)
            parameters.Env.Add($"{variable.Key}={variable.Value}");
    }
}