LuaCsForBarotraumaEP/Barotrauma/BarotraumaShared/SharedSource/LuaCs/Services/PackageManagementService.cs

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.Linq;
using System.Threading.Tasks;
using Barotrauma.LuaCs.Data;
using FluentResults;
using Microsoft.Toolkit.Diagnostics;

namespace Barotrauma.LuaCs.Services;

public sealed class PackageManagementService : IPackageManagementService
{
    // svc
    private ILoggerService _logger;
    private IModConfigService _modConfigService;
    private IConfigService _configService;
    private ILuaScriptManagementService _luaScriptManagementService;
    private IPluginManagementService _pluginManagementService;
    private IPackageManagementServiceConfig _runConfig;
    // state
    private readonly ConcurrentDictionary<ContentPackage, IModConfigInfo> _loadedPackages = new();
    private readonly ConcurrentDictionary<ContentPackage, IModConfigInfo> _runningPackages = new();
    // control
    /// <summary>
    /// Service Disposal Lock.
    /// </summary>
    private readonly AsyncReaderWriterLock _operationsLock = new();
    /// <summary>
    /// Execution of packages lock.
    /// <br/> Read: Package loading/unloading (Multi-operation mode).
    /// <br/> Write: Package execution (exclusive mode).
    /// </summary>
    private readonly AsyncReaderWriterLock _executionLock = new();
    
    public PackageManagementService(ILoggerService logger, 
        IModConfigService modConfigService, 
        ILuaScriptManagementService luaScriptManagementService, 
        IPluginManagementService pluginManagementService, 
        IConfigService configService, IPackageManagementServiceConfig runConfig)
    {
        _logger = logger;
        _modConfigService = modConfigService;
        _luaScriptManagementService = luaScriptManagementService;
        _pluginManagementService = pluginManagementService;
        _configService = configService;
        _runConfig = runConfig;
    }
    
    public void Dispose()
    {
        using var lck = _operationsLock.AcquireWriterLock().ConfigureAwait(false).GetAwaiter().GetResult();
        if (!ModUtils.Threading.CheckIfClearAndSetBool(ref _isDisposed))
            return;
        
        _logger.LogMessage($"{nameof(PackageManagementService)} is disposing.");
        _luaScriptManagementService.Dispose();
        _pluginManagementService.Dispose();
        _modConfigService.Dispose();
        _logger.Dispose();

        _logger = null;
        _luaScriptManagementService = null;
        _pluginManagementService = null;
        _modConfigService = null;
        _loadedPackages.Clear();
        _runningPackages.Clear();
    }

    private int _isDisposed = 0;
    public bool IsDisposed
    {
        get => ModUtils.Threading.GetBool(ref  _isDisposed);
        set => ModUtils.Threading.SetBool(ref  _isDisposed, value);
    }
    
    public FluentResults.Result Reset()
    {
        using var lck  = _operationsLock.AcquireWriterLock().ConfigureAwait(false).GetAwaiter().GetResult();
        if (IsDisposed)
            return FluentResults.Result.Fail($"{nameof(PackageManagementService)}failed to reset. Has already been disposed.");

        try
        {
            var operationResult = new FluentResults.Result();
            operationResult.WithReasons(_configService.Reset().Reasons);
            operationResult.WithReasons(_luaScriptManagementService.Reset().Reasons);
            operationResult.WithReasons(_pluginManagementService.Reset().Reasons);
            _runningPackages.Clear();
            _loadedPackages.Clear();
            return operationResult;
        }
        catch (Exception e)
        {
            return FluentResults.Result.Fail(new ExceptionalError(e));
        }
    }

    public FluentResults.Result LoadPackageInfo(ContentPackage package)
    {
        Guard.IsNotNull(package, nameof(package));
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        using var executeLock = _executionLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        
        IService.CheckDisposed(this);
        if (_loadedPackages.TryGetValue(package, out var result))
        {
            _logger.LogWarning($"{nameof(LoadPackageInfo)}: Tried to load already-loaded package {package.Name}.");
            return FluentResults.Result.Ok();
        }

        var pkgCfgInfo = _modConfigService.CreateConfigAsync(package).ConfigureAwait(false).GetAwaiter().GetResult();
        if (pkgCfgInfo.IsFailed)
        {
            _logger.LogResults(pkgCfgInfo.ToResult());
            return pkgCfgInfo.ToResult();
        }
        return UnsafeAddPackageInternal(package, pkgCfgInfo.Value);
    }

    public FluentResults.Result LoadPackagesInfo(ImmutableArray<ContentPackage> packages)
    {
        if (packages.IsDefaultOrEmpty)
            ThrowHelper.ThrowArgumentException($"{nameof(LoadPackagesInfo)}: packages list is empty.");
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        using var executeLock = _executionLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        
        IService.CheckDisposed(this);
        var result = new FluentResults.Result();
        var pkgConfigs = _modConfigService.CreateConfigsAsync([..packages]).ConfigureAwait(false).GetAwaiter().GetResult();
        foreach (var pkgConfig in pkgConfigs)
        {
            result.WithReasons(pkgConfig.Config.Reasons);
            if (pkgConfig.Config.IsSuccess)
                result.WithReasons(UnsafeAddPackageInternal(pkgConfig.Source, pkgConfig.Config.Value).Reasons);
        }

        return result;
    }

    private FluentResults.Result UnsafeAddPackageInternal(ContentPackage package, IModConfigInfo config)
    {
        if (_loadedPackages.TryGetValue(package, out var result))
        {
            _logger.LogWarning($"Tried to load already-loaded package {package.Name}.");
            return FluentResults.Result.Ok();
        }

        _loadedPackages[package] = config;
        var res = new FluentResults.Result();
        res.WithReasons(_luaScriptManagementService.LoadScriptResourcesAsync(config.LuaScripts).ConfigureAwait(false).GetAwaiter().GetResult().Reasons);
        return res;
    }

    public FluentResults.Result ExecuteLoadedPackages(ImmutableArray<ContentPackage> executionOrder)
    {
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        using var executeLock = _executionLock.AcquireWriterLock().ConfigureAwait(false).GetAwaiter().GetResult();
        IService.CheckDisposed(this);

        if (executionOrder.IsDefaultOrEmpty)
            return FluentResults.Result.Fail($"{nameof(ExecuteLoadedPackages)}: No packages in the execution order list.");
        
        if (!_runningPackages.IsEmpty)
        {
            return FluentResults.Result.Fail(
                $"{nameof(ExecuteLoadedPackages)}: There are already packages running! List: {
                    _runningPackages.Aggregate(string.Empty, (acc, kvp) => "-" + kvp + "\n" + kvp.Key.Name)}");
        }

        if (_loadedPackages.IsEmpty)
            return FluentResults.Result.Fail($"{nameof(ExecuteLoadedPackages)}: No packages loaded. Nothing to run!)");

        var result = new FluentResults.Result();
        
        // get loading order. Note: packages not in the execution order list will load first.
        var loadingOrderedPackages = _loadedPackages.OrderBy(pkg => executionOrder.IndexOf(pkg.Key))
            .ToImmutableArray();
        
        //mod settings
        var settings = loadingOrderedPackages
            .SelectMany(pkg => pkg.Value.Configs.OrderBy(scr => scr.LoadPriority))
            .ToImmutableArray();
        if (!settings.IsDefaultOrEmpty)
        {
            result.WithReasons(_configService.LoadConfigsAsync(settings).ConfigureAwait(false).GetAwaiter()
                .GetResult().Reasons);
            result.WithReasons(_configService.LoadConfigsProfilesAsync(settings).ConfigureAwait(false)
                .GetAwaiter().GetResult().Reasons);
        }
        
        //lua scripts
        var luaScripts = loadingOrderedPackages
            .SelectMany(pkg => pkg.Value.LuaScripts.OrderBy(scr => scr.LoadPriority))
            .ToImmutableArray();
        if (!luaScripts.IsDefaultOrEmpty)
            result.WithReasons(_luaScriptManagementService.ExecuteLoadedScripts(luaScripts).Reasons);

        if (_runConfig.IsCsEnabled)
        {
            var plugins =
                loadingOrderedPackages.SelectMany(pkg => pkg.Value.Assemblies.OrderBy(scr => scr.LoadPriority))
                    .ToImmutableArray();
            if (!plugins.IsDefaultOrEmpty)
                result.WithReasons(_pluginManagementService.LoadAssemblyResources(plugins).Reasons);
        }
        
        return result;
    }
    
    public FluentResults.Result StopRunningPackages()
    {
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        using var executeLock = _executionLock.AcquireWriterLock().ConfigureAwait(false).GetAwaiter().GetResult();
        IService.CheckDisposed(this);
        
        if (_loadedPackages.IsEmpty || _runningPackages.IsEmpty)
        {
            _logger.LogWarning($"{nameof(StopRunningPackages)}: No packages are currently executing.");
            return FluentResults.Result.Ok();
        }
        
        var res = new FluentResults.Result();
        res.WithReasons(_luaScriptManagementService.UnloadActiveScripts().Reasons);
        res.WithReasons(_pluginManagementService.UnloadManagedAssemblies().Reasons);
        _runningPackages.Clear();
        return res;
    }
    
    public FluentResults.Result UnloadPackage(ContentPackage package)
    {
        Guard.IsNotNull(package, nameof(package));
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        using var executeLock = _executionLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        IService.CheckDisposed(this);
        
        if (!_loadedPackages.ContainsKey(package))
            return FluentResults.Result.Fail($"{nameof(UnloadPackage)}: The package is not loaded.");
        if (!_runningPackages.IsEmpty)
            return FluentResults.Result.Fail($"{nameof(UnloadPackage)}: Packages are currently executing.");
        var result = new  FluentResults.Result();
        result.WithReasons(_luaScriptManagementService.DisposePackageResources(package).Reasons);
        result.WithReasons(_configService.DisposePackageData(package).Reasons);
        _loadedPackages.TryRemove(package, out _);
        return result;
    }
    
    public FluentResults.Result UnloadPackages(ImmutableArray<ContentPackage> packages)
    {
        if (packages.IsDefaultOrEmpty)
            return FluentResults.Result.Fail($"{nameof(UnloadPackages)}: Package list is empty.");
        
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        using var executeLock = _executionLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        IService.CheckDisposed(this);
        
        var result =  new FluentResults.Result();
        foreach (var package in packages)
            result.WithReasons(UnloadPackage(package).Reasons);
        return result;
    }

    public FluentResults.Result UnloadAllPackages()
    {
        using var lck = _operationsLock.AcquireWriterLock().ConfigureAwait(false).GetAwaiter().GetResult();
        using var executeLock = _executionLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        IService.CheckDisposed(this);
        
        if (_loadedPackages.IsEmpty)
            return FluentResults.Result.Ok();
        if (!_runningPackages.IsEmpty)
            return FluentResults.Result.Fail($"{nameof(UnloadAllPackages)}: Packages are currently executing.");
        var result = new FluentResults.Result();
        result.WithReasons(_luaScriptManagementService.DisposeAllPackageResources().Reasons);
        result.WithReasons(_configService.DisposeAllPackageData().Reasons);
        _loadedPackages.Clear();
        return result;
    }

    public ImmutableArray<ContentPackage> GetAllLoadedPackages()
    {
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        IService.CheckDisposed(this);
        return [.._loadedPackages.Keys];
    }

    public bool IsPackageRunning(ContentPackage package)
    {
        Guard.IsNotNull(package, nameof(package));
        using var lck = _operationsLock.AcquireReaderLock().ConfigureAwait(false).GetAwaiter().GetResult();
        IService.CheckDisposed(this);
        return _runningPackages.ContainsKey(package);
    }
}