Service Layer

15 specialized services for modular functionality - Clean separation of concerns

📋 Table of Contents

Overview
Service Architecture
Core Services
Feature Services
UI Services
Service Coordination
Code Examples

📖 Overview

The Service Layer provides modular, specialized functionality through 15 independent services, each responsible for a specific feature domain.

Design Principles:

✅ Single Responsibility - Each service has one clear purpose
✅ Loose Coupling - Services communicate through ViewModel
✅ Dependency Injection - Services receive dependencies via constructor
✅ Testability - Services can be unit-tested in isolation
✅ Reusability - Services can be used independently

Location: Services/

🏗️ Service Architecture

Component Diagram

graph TB
    subgraph "Presentation Layer"
        VM["HexEditorViewModel<br/>(Coordinator)"]
    end

    subgraph "Core Services"
        Search["SearchService"]
        Clipboard["ClipboardService"]
        UndoRedo["UndoRedoService"]
        Selection["SelectionService"]
    end

    subgraph "Feature Services"
        Bookmark["BookmarkService"]
        Highlight["HighlightService"]
        TBL["TBLService"]
        Compare["CompareService"]
        StatePersist["StatePersistenceService"]
    end

    subgraph "UI Services"
        Events["EventService"]
        Zoom["ZoomService"]
        UIHelper["UIHelperService"]
    end

    subgraph "Data Services"
        FileOps["FileOperationsService"]
        StreamOps["StreamOperationsService"]
        ByteOps["ByteOperationsService"]
    end

    VM --> Search
    VM --> Clipboard
    VM --> UndoRedo
    VM --> Selection
    VM --> Bookmark
    VM --> Highlight
    VM --> TBL
    VM --> Compare
    VM --> StatePersist
    VM --> Events
    VM --> Zoom
    VM --> UIHelper
    VM --> FileOps
    VM --> StreamOps
    VM --> ByteOps

    style VM fill:#e1f5ff,stroke:#0277bd,stroke-width:3px
    style Search fill:#c8e6c9,stroke:#388e3c,stroke-width:2px
    style Clipboard fill:#fff9c4,stroke:#f57c00,stroke-width:2px

Service Lifecycle

flowchart LR
    Create[Create ViewModel] --> InitServices[Initialize Services]
    InitServices --> ConfigureServices[Configure Services]
    ConfigureServices --> Ready[Services Ready]
    Ready --> UseServices[Use Services]
    UseServices --> Dispose[Dispose Services]

    style Create fill:#e1f5ff
    style Ready fill:#c8e6c9
    style Dispose fill:#ffccbc

⚙️ Core Services

1. SearchService

Purpose: Byte pattern and string search operations.

Location: SearchService.cs

Responsibilities:

Find byte patterns (FindFirst, FindNext, FindLast, FindAll)
String search with encoding support
Count occurrences (memory-efficient)
Highlight search results

API:

public class SearchService
{
    private readonly ByteProvider _provider;

    // Find operations
    public long FindFirst(byte[] pattern, long startPosition = 0);
    public long FindNext(byte[] pattern, long currentPosition);
    public long FindPrevious(byte[] pattern, long currentPosition);
    public long FindLast(byte[] pattern, long startPosition = -1);
    public List<long> FindAll(byte[] pattern, long startPosition = 0);

    // String search
    public long FindString(string text, Encoding encoding, long startPosition = 0);
    public List<long> FindAllStrings(string text, Encoding encoding);

    // Count
    public int CountOccurrences(byte[] pattern, long startPosition = 0);

    // Replace
    public int ReplaceFirst(byte[] find, byte[] replace);
    public int ReplaceAll(byte[] find, byte[] replace);
}

Example:

// Find pattern
var pattern = new byte[] { 0xDE, 0xAD, 0xBE, 0xEF };
long position = searchService.FindFirst(pattern);

if (position >= 0)
{
    Console.WriteLine($"Found at 0x{position:X}");
}

// Count occurrences
int count = searchService.CountOccurrences(pattern);
Console.WriteLine($"Total matches: {count}");

2. ClipboardService

Purpose: Clipboard operations with multiple format support.

Location: ClipboardService.cs

Responsibilities:

Copy bytes in multiple formats (Hex, ASCII, C# array, etc.)
Paste with format detection
Clipboard format conversion

Supported Formats:

Hex: DE AD BE EF
ASCII: DEADBEEF
C# Array: new byte[] { 0xDE, 0xAD, 0xBE, 0xEF }
C Array: {0xDE, 0xAD, 0xBE, 0xEF}
Binary: 11011110 10101101 10111110 11101111

API:

public class ClipboardService
{
    public void Copy(long position, long length, ClipboardFormat format);
    public void Paste(long position, ClipboardFormat format);
    public byte[] GetClipboardBytes(ClipboardFormat format);
    public bool CanPaste(ClipboardFormat format);
}

Example:

// Copy as C# array
clipboardService.Copy(0x100, 16, ClipboardFormat.CSharpArray);
// Clipboard: new byte[] { 0x41, 0x42, 0x43, ... }

// Paste from clipboard
clipboardService.Paste(0x200, ClipboardFormat.Auto);  // Auto-detect format

3. UndoRedoService

Purpose: History management (covered in Undo/Redo System).

API:

public class UndoRedoService
{
    public void Undo();
    public void Redo();
    public bool CanUndo { get; }
    public bool CanRedo { get; }
    public int UndoDepth { get; }
    public int RedoDepth { get; }
    public void ClearHistory();
}

4. SelectionService

Purpose: Text selection and range management.

Location: SelectionService.cs

Responsibilities:

Track selection start, end, length
Validate selection bounds
Raise selection changed events

API:

public class SelectionService
{
    public long SelectionStart { get; set; }
    public long SelectionLength { get; set; }
    public long SelectionEnd => SelectionStart + SelectionLength;

    public void SelectAll();
    public void ClearSelection();
    public void ExtendSelection(long newEnd);
    public bool HasSelection => SelectionLength > 0;

    public event EventHandler<SelectionChangedEventArgs> SelectionChanged;
}

Example:

// Select range
selectionService.SelectionStart = 0x100;
selectionService.SelectionLength = 256;

// Check selection
if (selectionService.HasSelection)
{
    Console.WriteLine($"Selected: 0x{selectionService.SelectionStart:X} - " +
                     $"0x{selectionService.SelectionEnd:X}");
}

// Select all
selectionService.SelectAll();

🎨 Feature Services

5. BookmarkService

Purpose: Bookmark management for quick navigation.

Location: BookmarkService.cs

API:

public class BookmarkService
{
    public void AddBookmark(long position, string description);
    public void RemoveBookmark(long position);
    public void ClearBookmarks();
    public List<Bookmark> GetBookmarks();
    public Bookmark GetBookmarkAt(long position);
    public bool HasBookmarkAt(long position);

    public event EventHandler<BookmarkEventArgs> BookmarkAdded;
    public event EventHandler<BookmarkEventArgs> BookmarkRemoved;
}

public class Bookmark
{
    public long Position { get; set; }
    public string Description { get; set; }
    public Color Color { get; set; }
}

Example:

// Add bookmarks
bookmarkService.AddBookmark(0x100, "File header start");
bookmarkService.AddBookmark(0x500, "Data section");
bookmarkService.AddBookmark(0x1000, "Footer");

// Navigate to bookmark
var bookmarks = bookmarkService.GetBookmarks();
foreach (var bm in bookmarks)
{
    Console.WriteLine($"{bm.Description} at 0x{bm.Position:X}");
}

6. HighlightService

Purpose: Custom background highlighting for byte ranges.

Location: HighlightService.cs

API:

public class HighlightService
{
    public void AddHighlight(long start, long length, Color color, string description);
    public void RemoveHighlight(long start);
    public void ClearHighlights();
    public List<Highlight> GetHighlights();
    public Highlight GetHighlightAt(long position);
}

public class Highlight
{
    public long StartPosition { get; set; }
    public long Length { get; set; }
    public Color Color { get; set; }
    public string Description { get; set; }
}

Example:

// Highlight file structure
highlightService.AddHighlight(0, 64, Colors.LightBlue, "DOS Header");
highlightService.AddHighlight(64, 248, Colors.LightGreen, "PE Header");
highlightService.AddHighlight(512, 1024, Colors.LightYellow, "Code Section");

7. TBLService

Purpose: Custom character table support (TBL files).

Location: TBLService.cs

API:

public class TBLService
{
    public void LoadTBL(string filePath);
    public void LoadTBLFromStream(Stream stream);
    public void UnloadTBL();
    public string GetCharacter(byte value);
    public bool HasTBL { get; }
}

Example:

// Load custom character table
tblService.LoadTBL("japanese.tbl");

// Read with custom characters
byte value = 0x81;
string character = tblService.GetCharacter(value);  // Returns Japanese character

8. CompareService

Purpose: Binary file comparison.

Location: CompareService.cs

API:

public class CompareService
{
    public CompareResult Compare(string file1, string file2);
    public List<Difference> GetDifferences(string file1, string file2);
}

public class Difference
{
    public long Position { get; set; }
    public byte File1Byte { get; set; }
    public byte File2Byte { get; set; }
}

Example:

// Compare two files
var result = compareService.Compare("original.bin", "modified.bin");
Console.WriteLine($"Files match: {result.AreEqual}");
Console.WriteLine($"Differences: {result.DifferenceCount}");

foreach (var diff in result.Differences)
{
    Console.WriteLine($"Position 0x{diff.Position:X}: " +
                     $"0x{diff.File1Byte:X2} vs 0x{diff.File2Byte:X2}");
}

9. StatePersistenceService

Purpose: Save and restore editor state.

Location: StatePersistenceService.cs

API:

public class StatePersistenceService
{
    public void SaveState(string stateFile);
    public void LoadState(string stateFile);
}

public class EditorState
{
    public string FileName { get; set; }
    public long Position { get; set; }
    public long SelectionStart { get; set; }
    public long SelectionLength { get; set; }
    public List<Bookmark> Bookmarks { get; set; }
    public List<Highlight> Highlights { get; set; }
}

Example:

// Save state
statePersistenceService.SaveState("session.state");

// Restore state later
statePersistenceService.LoadState("session.state");
// Bookmarks, highlights, position, and selection restored

🖥️ UI Services

10. EventService

Purpose: Event aggregation and routing.

Location: EventService.cs

API:

public class EventService
{
    public event EventHandler DataChanged;
    public event EventHandler LengthChanged;
    public event EventHandler<PositionEventArgs> PositionChanged;
    public event EventHandler<SelectionEventArgs> SelectionChanged;

    public void RaiseDataChanged();
    public void RaiseLengthChanged();
    public void RaisePositionChanged(long newPosition);
    public void RaiseSelectionChanged(long start, long length);
}

11. ZoomService

Purpose: Font size and zoom level management.

Location: ZoomService.cs

API:

public class ZoomService
{
    public double ZoomLevel { get; set; }
    public void ZoomIn();
    public void ZoomOut();
    public void ResetZoom();

    public event EventHandler<ZoomEventArgs> ZoomChanged;
}

Example:

// Zoom in
zoomService.ZoomIn();  // Increases by 10%

// Zoom out
zoomService.ZoomOut();  // Decreases by 10%

// Reset
zoomService.ResetZoom();  // Back to 100%

// Custom zoom
zoomService.ZoomLevel = 1.5;  // 150%

12. UIHelperService

Purpose: UI-related helper methods.

Location: UIHelperService.cs

API:

public class UIHelperService
{
    public void ScrollToPosition(long position);
    public void SetFocus();
    public void UpdateVisibleLines();
    public void InvalidateVisual();
}

📁 Data Services

13. FileOperationsService

Purpose: File I/O operations.

API:

public class FileOperationsService
{
    public void Open(string fileName);
    public void Save();
    public void SaveAs(string fileName);
    public void Close();
    public Task OpenAsync(string fileName, IProgress<double> progress);
    public Task SaveAsync(string fileName, IProgress<double> progress);
}

14. StreamOperationsService

Purpose: Stream-based data operations.

API:

public class StreamOperationsService
{
    public void OpenStream(Stream stream);
    public void OpenMemory(byte[] data);
    public Stream GetStream();
}

15. ByteOperationsService

Purpose: Low-level byte operations.

API:

public class ByteOperationsService
{
    public byte ReadByte(long position);
    public byte[] ReadBytes(long position, int count);
    public void ModifyByte(long position, byte value);
    public void ModifyBytes(long position, byte[] values);
    public void InsertByte(long position, byte value);
    public void InsertBytes(long position, byte[] values);
    public void DeleteByte(long position);
    public void DeleteBytes(long position, long count);
}

🔄 Service Coordination

ViewModel as Coordinator

public class HexEditorViewModel
{
    // All services
    public SearchService SearchService { get; }
    public ClipboardService ClipboardService { get; }
    public UndoRedoService UndoRedoService { get; }
    public SelectionService SelectionService { get; }
    public BookmarkService BookmarkService { get; }
    public HighlightService HighlightService { get; }
    public TBLService TBLService { get; }
    public CompareService CompareService { get; }
    public StatePersistenceService StatePersistenceService { get; }
    public EventService EventService { get; }
    public ZoomService ZoomService { get; }
    public UIHelperService UIHelperService { get; }
    public FileOperationsService FileOperationsService { get; }
    public StreamOperationsService StreamOperationsService { get; }
    public ByteOperationsService ByteOperationsService { get; }

    public HexEditorViewModel(ByteProvider provider)
    {
        // Initialize services with dependencies
        SearchService = new SearchService(provider);
        ClipboardService = new ClipboardService(provider);
        UndoRedoService = new UndoRedoService(provider);
        SelectionService = new SelectionService();
        BookmarkService = new BookmarkService();
        HighlightService = new HighlightService();
        TBLService = new TBLService();
        CompareService = new CompareService();
        StatePersistenceService = new StatePersistenceService(this);
        EventService = new EventService();
        ZoomService = new ZoomService();
        UIHelperService = new UIHelperService(this);
        FileOperationsService = new FileOperationsService(provider);
        StreamOperationsService = new StreamOperationsService(provider);
        ByteOperationsService = new ByteOperationsService(provider);

        // Wire up events
        WireUpEvents();
    }

    private void WireUpEvents()
    {
        // Subscribe to service events
        SearchService.SearchCompleted += OnSearchCompleted;
        SelectionService.SelectionChanged += OnSelectionChanged;
        BookmarkService.BookmarkAdded += OnBookmarkAdded;
        // ... more event subscriptions
    }
}

Service Communication

sequenceDiagram
    participant User
    participant VM as ViewModel
    participant Search as SearchService
    participant Selection as SelectionService
    participant Event as EventService

    User->>VM: Search for pattern
    VM->>Search: FindFirst(pattern)
    Search-->>VM: position
    VM->>Selection: SelectionStart = position
    VM->>Selection: SelectionLength = pattern.Length
    Selection->>Event: RaiseSelectionChanged()
    Event-->>VM: SelectionChanged event
    VM-->>User: Update UI

💻 Code Examples

Example 1: Using Multiple Services

// Search for pattern and bookmark matches
var pattern = new byte[] { 0xFF, 0xFF };
var positions = searchService.FindAll(pattern);

foreach (var pos in positions)
{
    bookmarkService.AddBookmark(pos, $"Pattern at 0x{pos:X}");
    highlightService.AddHighlight(pos, pattern.Length, Colors.Yellow, "Match");
}

Console.WriteLine($"Found {positions.Count} matches");

Example 2: Complex Operation with Services

// Find, select, copy operation
var pattern = new byte[] { 0xDE, 0xAD, 0xBE, 0xEF };
long position = searchService.FindFirst(pattern);

if (position >= 0)
{
    // Select found pattern
    selectionService.SelectionStart = position;
    selectionService.SelectionLength = pattern.Length;

    // Copy to clipboard
    clipboardService.Copy(position, pattern.Length, ClipboardFormat.HexString);

    // Add bookmark
    bookmarkService.AddBookmark(position, "Found pattern");

    // Highlight
    highlightService.AddHighlight(position, pattern.Length,
        Colors.LightGreen, "Match");
}

Example 3: Service Dependency Injection

// Custom service with dependencies
public class CustomAnalysisService
{
    private readonly SearchService _search;
    private readonly BookmarkService _bookmark;
    private readonly HighlightService _highlight;

    public CustomAnalysisService(
        SearchService search,
        BookmarkService bookmark,
        HighlightService highlight)
    {
        _search = search;
        _bookmark = bookmark;
        _highlight = highlight;
    }

    public void AnalyzeFileStructure()
    {
        // Use injected services
        var headers = _search.FindAll(new byte[] { 0x4D, 0x5A });  // MZ

        foreach (var pos in headers)
        {
            _bookmark.AddBookmark(pos, "PE Header");
            _highlight.AddHighlight(pos, 64, Colors.LightBlue, "Header");
        }
    }
}

🔗 See Also

Architecture Overview - System architecture
ByteProvider System - Data access coordination
Services Folder - Service implementations

Last Updated: 2026-02-19 Version: V2.0

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Service Layer

📋 Table of Contents

📖 Overview

🏗️ Service Architecture

Component Diagram

Service Lifecycle

⚙️ Core Services

1. SearchService

2. ClipboardService

3. UndoRedoService

4. SelectionService

🎨 Feature Services

5. BookmarkService

6. HighlightService

7. TBLService

8. CompareService

9. StatePersistenceService

🖥️ UI Services

10. EventService

11. ZoomService

12. UIHelperService

📁 Data Services

13. FileOperationsService

14. StreamOperationsService

15. ByteOperationsService

🔄 Service Coordination

ViewModel as Coordinator

Service Communication

💻 Code Examples

Example 1: Using Multiple Services

Example 2: Complex Operation with Services

Example 3: Service Dependency Injection

🔗 See Also

FilesExpand file tree

service-layer.md

Latest commit

History

service-layer.md

File metadata and controls

Service Layer

📋 Table of Contents

📖 Overview

🏗️ Service Architecture

Component Diagram

Service Lifecycle

⚙️ Core Services

1. SearchService

2. ClipboardService

3. UndoRedoService

4. SelectionService

🎨 Feature Services

5. BookmarkService

6. HighlightService

7. TBLService

8. CompareService

9. StatePersistenceService

🖥️ UI Services

10. EventService

11. ZoomService

12. UIHelperService

📁 Data Services

13. FileOperationsService

14. StreamOperationsService

15. ByteOperationsService

🔄 Service Coordination

ViewModel as Coordinator

Service Communication

💻 Code Examples

Example 1: Using Multiple Services

Example 2: Complex Operation with Services

Example 3: Service Dependency Injection

🔗 See Also