sequenceDiagram
    actor WPF as WPFFramework
    participant MI as MyImage
    participant Disp as Dispatcher
    participant Tasks as DownloadTasks
    participant Http as HttpRequestBuilder

    WPF->>MI: Initialized event
    MI->>MI: Load
    MI->>Disp: BeginInvoke(async delegate)
    activate Disp
    Disp->>MI: Async lambda execution
    MI->>MI: ActualSource = LoadingSource

    MI->>Tasks: GetOrAdd(Url, DownloadImage)
    alt New task for Url
        Tasks->>MI: Returns new Task for Url
        MI->>Http: Create(Url).SendAsync()
        Http-->>MI: HttpResponseMessage
        MI->>MI: Save stream to temp file
        MI->>MI: Move to cache path
        MI-->>Tasks: Return temp path
    else Existing task for Url
        Tasks-->>MI: Existing Task for Url
    end

    MI->>Tasks: await Task for Url
    alt Url download succeeded
        MI->>MI: ActualSource = urlTempPath
        Disp-->>MI: Async lambda returns
    else Url download failed or returned empty
        MI->>Tasks: GetOrAdd(FallbackSource, DownloadImage)
        alt New task for FallbackSource
            Tasks->>MI: Returns new Task for FallbackSource
            MI->>Http: Create(FallbackSource).SendAsync()
            Http-->>MI: HttpResponseMessage
            MI->>MI: Save stream to temp file
            MI->>MI: Move to fallback cache path
            MI-->>Tasks: Return fallback temp path
        else Existing task for FallbackSource
            Tasks-->>MI: Existing Task for FallbackSource
        end

        MI->>Tasks: await Task for FallbackSource
        alt Fallback succeeded
            MI->>MI: ActualSource = fallbackTempPath
        else Fallback failed or returned empty
            MI->>MI: Try load from local cache for Url
        end
    end

    Disp-->>WPF: UI updated with ActualSource

classDiagram
    class MyImage {
        +CornerRadius CornerRadius
        +String Source
        +String LoadingSource
        +String FallbackSource
        +Boolean EnableCache
        -String _ActualSource
        +String ActualSource
        -Shared ConcurrentDictionary~String, Task~String~~ _downloadTasks
        +Sub Load()
        +Sub UpdateClip()
        +Shared Function GetTempPath(Url As String) String
        -Shared Async Function DownloadImage(url As String) Task~String~
    }

    class MyBitmap {
        +Sub New()
        +Sub LoadFromPath(FilePathOrResourceName As String)
    }

    class MyListItem {
        +String Title
        +String Info
        +String Logo
        +Object Tags
        +Object Tag
        +Object PathLogo
        +Sub New()
    }

    MyListItem "1" o-- "1" MyImage : PathLogo
    MyBitmap ..> MyImage : loads image files for
    MyImage ..> ConcurrentDictionary : uses
    class ConcurrentDictionary {
        +Function GetOrAdd(key As String, valueFactory As Func~String, Task~String~~) Task~String~
        +Function Remove(key As String, value As Task~String~) Boolean
    }

flowchart TD
    A[Start DownloadImage url] --> B[Compute tempPath = GetTempPath url]
    B --> C[Compute TempDownloadingPath = tempPath + random]
    C --> D[CreateDirectory GetPathFromFullPath tempPath]
    D --> E[Create FileStream TempDownloadingPath]
    E --> F[SendAsync HttpRequestBuilder for url]
    F --> G{response.EnsureSuccessStatusCode}
    G -->|Success| H[Get response.AsStreamAsync]
    H --> I[Copy network stream to FileStream]
    I --> J[Dispose streams]
    J --> K[File.Move TempDownloadingPath to tempPath]
    K --> L[Return tempPath]

    G -->|Throws exception| X[Catch Exception]
    X --> M{File.Exists tempPath}
    M -->|Yes| N[File.Delete tempPath]
    M -->|No| O[Skip delete tempPath]
    N --> P{File.Exists TempDownloadingPath}
    O --> P
    P -->|Yes| Q[File.Delete TempDownloadingPath]
    P -->|No| R[Skip delete TempDownloadingPath]
    Q --> S[Log failure with url and tempPath]
    R --> S
    S --> T[Return String.Empty]
    T --> U[End]