SCR_DownloadManager.c

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/*
This entity is required for SCR_DownloadManager_Dialog to work.
 
It performs tracking of current downloads, while the Dialog class just visualizes them when opened.
 
!!! This entity relies on SCR_AddonManager, which also must be placed into the world.
*/
 
[EntityEditorProps(category: "", description: "Entity of the download manager. Most likely only needed in the main menu world.")]
class SCR_DownloadManagerClass: GenericEntityClass
{
};
 
void ScriptInvoker_DownloadManagerAction(SCR_WorkshopItemActionDownload action);
typedef func ScriptInvoker_DownloadManagerAction;
 
void ScriptInvoker_DownloadManagerActionError(SCR_WorkshopItemActionDownload action, int reason);
typedef func ScriptInvoker_DownloadManagerActionError;
 
class SCR_DownloadManager : GenericEntity
{
    protected const int DOWNLOAD_STUCK_DELAY = 60; // Max time in which download needs to progress in seconds
    
    protected const int ERROR_FULL_STORAGE = 19;
    
    protected static SCR_DownloadManager s_Instance;
    
    // All download actions
    protected ref array<ref SCR_DownloadManager_Entry> m_aDownloadActions = new array<ref SCR_DownloadManager_Entry>();
    
    // Download queue - it gets empty once all active downloads are complete, but keeps added up if new downloads are started
    // While previous are in progress.
    // This is mainly used by the panel.
    protected ref array<ref SCR_WorkshopItemActionDownload> m_aDownloadQueue = new array<ref SCR_WorkshopItemActionDownload>;
    protected int m_iQueueDownloadsCompleted; // Amount of completed downloads in the queue
    
    protected float m_fNoDownloadProgressTimer = 0; // Track how long there was no progress on downloading until stuck delay
    protected float m_fDownloadQueueSize;
    protected float m_fDownloadedSize;
    
    // Bool to pause all downloads
    protected bool m_bDownloadsPaused;
    
    protected const int FAIL_TIME = 500;
    protected ref array<ref SCR_WorkshopItemActionDownload> m_aFailedDownloads = {};

    ref ScriptInvoker m_OnNewDownload = new ScriptInvoker; // (SCR_WorkshopItem item, SCR_WorkshopItemActionDownload action)
    
    ref ScriptInvokerBase<ScriptInvoker_DownloadManagerAction> m_OnDownloadComplete = new ScriptInvokerBase<ScriptInvoker_DownloadManagerAction>();
    ref ScriptInvokerBase<ScriptInvoker_DownloadManagerActionError> m_OnDownloadFailed = new ScriptInvokerBase<ScriptInvoker_DownloadManagerActionError>();
    protected ref ScriptInvokerBase<ScriptInvoker_ActionDownloadFullStorage> m_OnFullStorageError;
    ref ScriptInvokerBase<ScriptInvoker_DownloadManagerAction> m_OnDownloadCanceled = new ScriptInvokerBase<ScriptInvoker_DownloadManagerAction>();
    protected ref ScriptInvokerVoid m_OnDownloadQueueCompleted
    protected ref ScriptInvokerVoid m_OnAllDownloadsStopped;
    
    //------------------------------------------------------------------------------------------------
    ScriptInvokerBase<ScriptInvoker_ActionDownloadFullStorage> GetOnFullStorageError()
    {
        if (!m_OnFullStorageError)
            m_OnFullStorageError = new ScriptInvokerBase<ScriptInvoker_ActionDownloadFullStorage>();
        
        return m_OnFullStorageError;
    }
    
    //-----------------------------------------------------------------------------------------------
    ScriptInvokerVoid GetOnDownloadQueueCompleted()
    {
        if (!m_OnDownloadQueueCompleted)
            m_OnDownloadQueueCompleted = new ScriptInvokerVoid();
        
        return m_OnDownloadQueueCompleted;
    }
    
    //-----------------------------------------------------------------------------------------------
    ScriptInvokerVoid GetOnAllDownloadsStopped()
    {
        if (!m_OnAllDownloadsStopped)
            m_OnAllDownloadsStopped = new ScriptInvokerVoid();
        
        return m_OnAllDownloadsStopped;
    }
    
    //-----------------------------------------------------------------------------------------------
    //              P U B L I C   A P I 
    //-----------------------------------------------------------------------------------------------
    
    
    //-----------------------------------------------------------------------------------------------
    static SCR_DownloadManager GetInstance()
    {
        return s_Instance;
    }
    
    //-----------------------------------------------------------------------------------------------
    void GetAllDownloads(array<ref SCR_DownloadManager_Entry> downloads)
    {
        downloads.Clear();
        
        foreach (auto dl : m_aDownloadActions)
            downloads.Insert(dl);
    }
    
    
    //-----------------------------------------------------------------------------------------------
    void GetDownloadQueueState(out int nCompleted, out int nTotal)
    {
        nTotal = m_aDownloadQueue.Count();
        nCompleted = m_iQueueDownloadsCompleted;
    }
    
    //-----------------------------------------------------------------------------------------------
    bool HasRunningDownloads()
    {
        return !m_aDownloadQueue.IsEmpty();
    }
    
    //-----------------------------------------------------------------------------------------------
    SCR_WorkshopItemActionDownload DownloadingActionAddonById(string id, bool runningOnly = true)
    {
        foreach (SCR_WorkshopItemActionDownload download : m_aDownloadQueue)
        {
            if (download.m_Wrapper.GetId() != id)
                continue;
            
            if (runningOnly && download.IsActive() && !download.IsCompleted() && !download.IsFailed() && !download.IsCanceled())
                return download;
        }
        
        return null;
    }
    
    //-----------------------------------------------------------------------------------------------
    array<ref SCR_WorkshopItemActionDownload> GetDownloadQueue()
    {
        array<ref SCR_WorkshopItemActionDownload> downloads = {};
        
        if (!m_aDownloadQueue)
            return downloads;
        
        foreach (SCR_WorkshopItemActionDownload action : m_aDownloadQueue)
        {
            downloads.Insert(action);
        }
        
        return downloads;
    }
    
    //-----------------------------------------------------------------------------------------------
    SCR_WorkshopItemActionDownload GetActionOfItem(SCR_WorkshopItem item)
    {
        foreach (SCR_DownloadManager_Entry entry : m_aDownloadActions)
        {
            if (entry.m_Item == item)
                return entry.m_Action;
        }
        
        return null;
    }
    
    //-----------------------------------------------------------------------------------------------
    void SetDownloadsPaused(bool pause, int count = -1)
    {
        if (pause == m_bDownloadsPaused)
            return;
        
        m_bDownloadsPaused = pause;
 
        // Setup calls count
        if (count == -1)
            count = m_aDownloadQueue.Count() - 1;
        
        // Paseu/resume
        PauseAction(m_aDownloadQueue[count], pause);
        
        // Late call 
        if (count > 0)
            GetGame().GetCallqueue().CallLater(SetDownloadsPaused, 0, false, pause, count - 1);
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void PauseAction(SCR_WorkshopItemActionDownload action, bool pause)
    {
        // Pause 
        if (pause)
        {
            if (action.IsActive())
                action.Pause();
            
            return;
        }
        
        // Resume
        if (action.IsPaused())
            action.Resume();
        else if (action.IsInactive())
            action.Activate();
    }
    
    //-----------------------------------------------------------------------------------------------
    bool GetDownloadsPaused()
    {
        return m_bDownloadsPaused;
    }
    
    
    //-----------------------------------------------------------------------------------------------
    void EndAllDownloads()
    {
        foreach (SCR_WorkshopItemActionDownload a : m_aDownloadQueue)
        {
            a.Cancel();
        }
    }
    
    //-----------------------------------------------------------------------------------------------
    // Given an array of required items, returns all those queued items that are outside of it, including mismatching versions
    array<ref SCR_WorkshopItemActionDownload> GetUnrelatedDownloads(array<ref SCR_WorkshopItem> requiredItems)
    {
        array<ref SCR_WorkshopItemActionDownload> unrelatedDownloads = {};
    
        foreach (SCR_WorkshopItemActionDownload action : m_aDownloadQueue)
        {
            if (!IsDownloadingActionRequired(action, requiredItems))
                unrelatedDownloads.Insert(action);
        }
        
        return unrelatedDownloads;
    }
    
    //-----------------------------------------------------------------------------------------------
    // Given an array of required items, returns true if the input action's item is part of it and is the correct version
    bool IsDownloadingActionRequired(SCR_WorkshopItemActionDownload action, array<ref SCR_WorkshopItem> requiredItems)
    {
        SCR_WorkshopItem item = action.GetWorkshopItem();
        if (!item)
            return true;
        
        bool required;
        bool sameId;
        bool sameVersion;       
        
        foreach (SCR_WorkshopItem requiredItem : requiredItems)
        {   
            sameId = requiredItem.GetId() == item.GetId();
            sameVersion = requiredItem.GetDependency().GetVersion() == action.GetTargetRevision().GetVersion();
            required = sameId && sameVersion;
 
            if (required)
                return true;
        }
        
        return false;   
    }
    
    // --- Helper functions for generic download functionality ---
    
    //-----------------------------------------------------------------------------------------------
    static bool IsLatestDownloadRequired(SCR_WorkshopItem item)
    {
        if (!item.GetOffline())
            return true;
        
        Revision latestRevision = item.GetLatestRevision();
        Revision targetRevision;
        bool downloading, paused;
        float progress;
        item.GetDownloadState(downloading, paused, progress, targetRevision);
        
        if (!downloading)
        {
            return !Revision.AreEqual(item.GetCurrentLocalRevision(), latestRevision);
        }
        else
        {
            // We are already downloading this, but what versoin?
            if (Revision.AreEqual(item.GetLatestRevision(), targetRevision))
                return false; // Already downloading this version, no need to start a new download
            else
                return true;    // Downloading a different version, we must download another one
        }
    }
    
    
    //-----------------------------------------------------------------------------------------------
    static void SelectAddonsForLatestDownload(array<ref SCR_WorkshopItem> arrayIn, array<ref SCR_WorkshopItem> arrayOut)
    {
        foreach (SCR_WorkshopItem addon : arrayIn)
        {
            if (IsLatestDownloadRequired(addon))
                arrayOut.Insert(addon);
        }
    }
    
    //-----------------------------------------------------------------------------------------------
    array<ref SCR_WorkshopItemAction> DownloadLatestWithDependencies(notnull SCR_WorkshopItem mainItem, bool downloadMainItem, array<ref SCR_WorkshopItem> dependencies)
    {
        array<ref SCR_WorkshopItemAction> actions = {};
        
        if (IsLatestDownloadRequired(mainItem) && downloadMainItem)
        {
            auto actionMain = mainItem.DownloadLatestVersion();
            if (actionMain)
            {
                actions.Insert(actionMain);
                if (!m_bDownloadsPaused)
                    actionMain.Activate();
            }
        }
        
        if (dependencies)
        {
            if (dependencies.Count() > 0)
            {
                auto actionDependencies = mainItem.DownloadDependenciesLatest(dependencies);
                if (actionDependencies)
                {
                    if (!m_bDownloadsPaused)
                        actionDependencies.Activate();
                    
                    actions.Insert(actionDependencies);
                }
            }
        }
        
        return actions;
    }
    
    //-----------------------------------------------------------------------------------------------
    
    //-----------------------------------------------------------------------------------------------
    array<ref SCR_WorkshopItemActionDownload> DownloadItems(array<ref SCR_WorkshopItem> items)
    {
        array<ref SCR_WorkshopItemActionDownload> actions = {};
        
        for (int i = 0, count = items.Count(); i < count; i++)
        {
            Revision target = items[i].GetItemTargetRevision();
            
            if (!target)
                target = items[i].GetDependency().GetRevision();
            
            if (!target)
            {
                return null;
            }
            
            // Create download action from dependency and depdency revision
            SCR_WorkshopItemActionDownload action = items[i].Download(target);
            actions.Insert(action); 
            action.Activate();
        }
        
        return actions; 
    }
    
    //-----------------------------------------------------------------------------------------------
    void DownloadDependecies(array<Dependency> dependencies)
    {
        for (int i = 0, count = dependencies.Count(); i < count; i++)
        {
            SCR_WorkshopItem item = SCR_WorkshopItem.Internal_CreateFromDependency(dependencies[i]);
            
            // Create download action from dependency and depdency revision
            SCR_WorkshopItemActionDownload action = item.Download(dependencies[i].GetRevision());   
            action.Activate();
        }
    }
    
    //-----------------------------------------------------------------------------------------------
    static float GetTotalSizeBytes(array<ref SCR_WorkshopItem> arrayIn, SCR_WorkshopItem extraItem = null)
    {
        float sizeOut = 0;
        
        foreach (SCR_WorkshopItem addon : arrayIn)
        {
            float s = addon.GetTargetRevisionPatchSize();
            sizeOut += s;
        }
        
        if (extraItem)
        {
            float s = extraItem.GetTargetRevisionPatchSize();
            sizeOut += s;
        }
        
        return sizeOut;
    }
    
    //-----------------------------------------------------------------------------------------------
    protected float DownloadQueueSize()
    {
        array<ref SCR_WorkshopItem> downloading = {};
        for (int i = 0, count = m_aDownloadQueue.Count(); i < count; i++)
        {
            downloading.Insert(m_aDownloadQueue[i].m_Wrapper);
        }
        
        return GetTotalSizeBytes(downloading);
    }
    
    //-----------------------------------------------------------------------------------------------
    static float GetDownloadActionsProgress(array<ref SCR_WorkshopItemActionDownload> actions)
    {
        float totalSizeBytes = 0;
        float totalBytesDownloaded = 0;
        
        foreach (SCR_WorkshopItemActionDownload dl : actions)
        {
            float dlsize = dl.GetSizeBytes();
            totalSizeBytes += dlsize;
            totalBytesDownloaded += dl.GetProgress() * dlsize;
        }
        
        if (totalSizeBytes == 0) // Don't divide by 0
            return 0;
        
        float progress = totalBytesDownloaded / totalSizeBytes;
        return progress;
    }
 
    //-----------------------------------------------------------------------------------------------
    static float GetItemDownloadActionsProgress(SCR_WorkshopItem item)
    {
        // Create an array of all download actions started from this tile
        // Get their aggregated progress
        
        SCR_WorkshopItemActionDownload actionThisItem = item.GetDownloadAction();                   // Action for downloading this item
        SCR_WorkshopItemActionComposite actionDependencies = item.GetDependencyCompositeAction();   // Action for downloading dependencies
        
        array<ref SCR_WorkshopItemAction> allActions;
        if (actionDependencies)
            allActions = actionDependencies.GetActions();
        else
            allActions = new array<ref SCR_WorkshopItemAction>;
        
        if (actionThisItem)
            allActions.Insert(actionThisItem);
        
        // Cast all actions to download actions...
        auto allDownloadActions = new array<ref SCR_WorkshopItemActionDownload>;
        foreach (auto a : allActions)
        {
            auto downloadAction = SCR_WorkshopItemActionDownload.Cast(a);
            if (downloadAction)
                allDownloadActions.Insert(downloadAction);
        }
        
        float progress = SCR_DownloadManager.GetDownloadActionsProgress(allDownloadActions);
        
        return progress;
    }
    
    //-----------------------------------------------------------------------------------------------
    array<ref SCR_WorkshopItemActionDownload> GetFailedDownloads()
    {
        array<ref SCR_WorkshopItemActionDownload> actions = {};
        for (int i = 0, count = m_aFailedDownloads.Count(); i < count; i++)
        {
            actions.Insert(m_aFailedDownloads[i]);  
        }
        
        return actions;
    }
    
    //-----------------------------------------------------------------------------------------------
    void ClearFailedDownloads()
    {
        m_aFailedDownloads.Clear();
    }
    
    //-----------------------------------------------------------------------------------------------
    void AddDownloadManagerEntry(notnull SCR_WorkshopItem item, notnull SCR_WorkshopItemActionDownload action)
    {
        RemoveSameAddonFromDownloads(item);
        
        SCR_DownloadManager_Entry entry = new SCR_DownloadManager_Entry(item, action);
        m_aDownloadActions.Insert(entry);
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void RemoveSameAddonFromDownloads(notnull SCR_WorkshopItem item)
    {
        // Release download actions
        for (int i = 0, count = m_aDownloadActions.Count(); i < count; i++)
        {
            // Same addon ids?
            if (m_aDownloadActions[i].m_Item.GetId() == item.GetId())
            {
                m_aDownloadActions.Remove(i);
                break;
            }
        }
        
        // Release download queue 
        for (int i = 0, count = m_aDownloadQueue.Count(); i < count; i++)
        {
            // Same addon ids?
            if (m_aDownloadQueue[i].m_Wrapper.GetId() == item.GetId())
            {
                m_aDownloadQueue.Remove(i);
                break;
            }
        }
    }
    
    //-----------------------------------------------------------------------------------------------
    float GetDownloadQueueSize()
    {
        return m_fDownloadQueueSize;
    }
    
    //-----------------------------------------------------------------------------------------------
    float GetDownloadedSize()
    {
        return m_fDownloadedSize;
    }
    
    //-----------------------------------------------------------------------------------------------
    //-----------------------------------------------------------------------------------------------
    //-----------------------------------------------------------------------------------------------
    
    
    
    
    
 
    
    
    //-----------------------------------------------------------------------------------------------
    //                  P R O T E C T E D   /   P R I V A T E
    //-----------------------------------------------------------------------------------------------
    
    
    
    //-----------------------------------------------------------------------------------------------
    override void EOnFrame(IEntity owner, float timeSlice)
    {
        int pausedCount = 0;
        
        // Remove failed or canceled actions from the download queue
        for (int i = m_aDownloadQueue.Count() - 1; i >= 0; i--)
        {
            SCR_WorkshopItemActionDownload action = m_aDownloadQueue[i];
 
            if (action.IsCanceled() || action.IsFailed())
                ClearUnfinishedAction(action);
            else if (action.IsPaused()) 
                pausedCount++;
        }
        
        // Restart no progress timer check
        if (pausedCount == m_aDownloadQueue.Count())
        {
            m_fNoDownloadProgressTimer = 0;
        }
        
        // If all are completed, clear the queue entirely
        // And reset 'all downloads paused' state.
        if (!m_aDownloadQueue.IsEmpty() && m_iQueueDownloadsCompleted == m_aDownloadQueue.Count())
        {
            m_aDownloadQueue.Clear();
            m_iQueueDownloadsCompleted = 0;
            m_fDownloadedSize = 0;
            m_bDownloadsPaused = false;
 
            if (m_OnDownloadQueueCompleted)
                m_OnDownloadQueueCompleted.Invoke();
            
            m_fNoDownloadProgressTimer = 0;
        }
        
        /*
        else 
        {
            // Increase time from last download progress
            m_fNoDownloadProgressTimer += timeSlice;
            
            // Quit downloads if nothing is progressing
            if (m_fNoDownloadProgressTimer >= DOWNLOAD_STUCK_DELAY)
            {
                // TODO: Display error if no progress for 1 min istead of force fail
            }
        }
        */
    }
    
    //-----------------------------------------------------------------------------------------------
    override void EOnInit(IEntity owner)
    {
        SCR_AddonManager addonManager = SCR_AddonManager.GetInstance();
        
        if (!addonManager)
        {
            Print("SCR_DownloadManager_Entity: SCR_AddonManager was not found. It must be placed in the world for download manager to work.", LogLevel.ERROR);
            return;
        }
        
        addonManager.m_OnNewDownload.Insert(Callback_OnNewDownload);
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void Callback_OnNewDownload(SCR_WorkshopItem item, SCR_WorkshopItemActionDownload action)
    {
        #ifdef WORKSHOP_DEBUG
        Revision rev = action.GetTargetRevision();
        if (rev)
            _print(string.Format("Callback_OnNewDownloadStarted: %1, %2", item.GetName(), action.GetTargetRevision().GetVersion()));
        else
            _print(string.Format("Callback_OnNewDownloadStarted: %1", item.GetName()));
        #endif
        
        RemoveSameAddonFromDownloads(item);
        
        // Create a new entry
        SCR_DownloadManager_Entry entry = new SCR_DownloadManager_Entry(item, action);
        m_aDownloadActions.Insert(entry);
        
        // Add the action to the queue
        m_aDownloadQueue.Insert(action);
        m_fDownloadQueueSize = DownloadQueueSize();
        
        m_OnNewDownload.Invoke(item, action);
        
        action.GetOnDownloadProgress().Insert(OnDownloadProgress);
        action.m_OnCompleted.Insert(Callback_OnDownloadCompleted);
        action.m_OnFailed.Insert(Callback_OnFailed);
        action.GetOnFullStorageError().Insert(Callback_OnFullStorageError);
        action.m_OnCanceled.Insert(Callback_OnCanceled);
        
        m_fNoDownloadProgressTimer = 0;
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void OnDownloadProgress(SCR_WorkshopItemActionDownload action, float progressSize)
    {
        m_fDownloadedSize += progressSize;
        
        // Restart progress timer
        m_fNoDownloadProgressTimer = 0;
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void Callback_OnDownloadCompleted(SCR_WorkshopItemActionDownload action)
    {   
        // Check user's settings if we need to enable the addon automatically
        // Ignore this if it was an update of an addon
        SCR_WorkshopSettings settings = SCR_WorkshopSettings.Get();
        if (settings.m_bAutoEnableDownloadedAddons && !action.GetUpdate())
        {   
            SCR_WorkshopItem item = action.GetWorkshopItem();
            
            if (!item)
                return;
            
            item.SetEnabled(true);
        }
        
        // Invoke for UI
        m_iQueueDownloadsCompleted++;
        m_OnDownloadComplete.Invoke(action);
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void Callback_OnFailed(SCR_WorkshopItemActionDownload action, int reason)
    {   
        m_aFailedDownloads.Insert(action);
        
        // TODO: hack, download manager should not open UI, but we lack a proper system to handle this better
        SCR_FailedModsDownloadDialog.ShowFailedModsDialog(action, reason);
        
        // Prevent error on full storage error
        if (reason == ERROR_FULL_STORAGE)
            return;
        
        // Generic error 
        m_OnDownloadFailed.Invoke(action, reason);
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void Callback_OnFullStorageError(SCR_WorkshopItemActionDownload action, float size)
    {   
        // TODO: hack, download manager should not open UI, but we lack a proper system to handle this better
        SCR_NotEnoughStorageDialog.ShowNotEnoughStorageDialog(size, action);
        
        if (m_OnFullStorageError)
            m_OnFullStorageError.Invoke(action, size);
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void Callback_OnCanceled(SCR_WorkshopItemActionDownload action)
    {   
        m_aFailedDownloads.Insert(action);
        m_OnDownloadCanceled.Invoke(action);
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void ForceFailRunningDownloads()
    {
        for (int i = 0, count = m_aDownloadQueue.Count(); i < count; i++)
        {
            m_aDownloadQueue[i].ForceFail();
        }
    }
    
    //-----------------------------------------------------------------------------------------------
    void DownloadAddons(array<ref SCR_WorkshopItem> items)
    {
        SCR_DownloadSequence sequence = SCR_DownloadSequence.Create(items, null, true);
        sequence.GetOnReady().Insert(OnDownloadAddonsReady);
        sequence.Init();
        
        /*
        array<ref SCR_WorkshopItem> offline = SCR_AddonManager.GetInstance().GetOfflineAddons();
        array<SCR_WorkshopItem> unfinished = {};
        
        // Filter out unfinished 
        foreach (SCR_WorkshopItem item : offline)
        {
            bool inProgress, paused;
            int progress;
            Revision targetRevision;
            
            item.GetDownloadState(inProgress, paused, progress, targetRevision);
            Print("item: " + item.GetName());
            Print("in progress: " + inProgress);
            Print("----------------------------------");
            
            //Print("item: " + item.GetDownloadState());
            //if (offline.ge)
        }
        */
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void OnDownloadAddonsReady(SCR_DownloadSequence sequence)
    {
        sequence.GetOnReady().Remove(OnDownloadAddonsReady);
        //sequence.
    }
    
    //-----------------------------------------------------------------------------------------------
    protected void ClearUnfinishedAction(SCR_WorkshopItemActionDownload action)
    {
        m_aDownloadQueue.RemoveItem(action);
                    
        // Remove canceled and failed from size count 
        m_fDownloadQueueSize = Math.Clamp(m_fDownloadQueueSize - action.GetDownloadSize(), 0, float.MAX);
        m_fDownloadedSize = Math.Clamp(m_fDownloadedSize - action.GetDownloadSize(), 0, float.MAX);
        
        if (m_OnAllDownloadsStopped && m_aDownloadQueue.IsEmpty())
            m_OnAllDownloadsStopped.Invoke();
    }
    
    //-----------------------------------------------------------------------------------------------
    private void SCR_DownloadManager(IEntitySource src, IEntity parent)
    {
        SetEventMask( EntityEvent.FRAME | EntityEvent.INIT);
        SetFlags(EntityFlags.NO_TREE | EntityFlags.NO_LINK);
        
        s_Instance = this;
    }
    
    //-----------------------------------------------------------------------------------------------
    private void ~SCR_DownloadManager()
    {
        s_Instance = null;
    }
    
    
    //-----------------------------------------------------------------------------------------------
    //-----------------------------------------------------------------------------------------------
    //-----------------------------------------------------------------------------------------------
 
    
    //------------------------------------------------------------------------------------------------
    void _print(string str, LogLevel logLevel = LogLevel.DEBUG)
    {
        Print(string.Format("[SCR_DownloadManager] %1 %2", this, str), logLevel);
    }   
};
 
 
//------------------------------------------------------------------------------------------------
class SCR_DownloadManager_Entry
{
    ref SCR_WorkshopItem m_Item;                    // We hold strong refs to both item and action!
    ref SCR_WorkshopItemActionDownload m_Action;
    
    //------------------------------------------------------------------------------------------------
    void SCR_DownloadManager_Entry(SCR_WorkshopItem item, SCR_WorkshopItemActionDownload action)
    {
        m_Item = item;
        m_Action = action;
    }
};
 
//------------------------------------------------------------------------------------------------
enum EDownloadManagerActionState
{
    INACTIVE,
    RUNNING,
    FAILED,
    DOWNLOADED,
};