feat: public API for fluent presentation builder

Clippit/PowerPoint/Fluent/FluentPresentationBuilder.Deduplication.cs

@@ -0,0 +1,118 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using DocumentFormat.OpenXml.Packaging;
+using DocumentFormat.OpenXml.Presentation;
+
+namespace Clippit.PowerPoint.Fluent;
+
+internal partial class FluentPresentationBuilder
+{
+    private readonly List<ContentData> _mediaCache = [];
+    private readonly List<SlideMasterData> _slideMasterList = [];
+    private SlideSize _slideSize;
+
+    private void InitializeCaches()
+    {
+        if (_newDocument.PresentationPart is not { } presentation)
+            return;
+
+        foreach (var slideMasterPart in presentation.SlideMasterParts)
+        {
+            foreach (var slideLayoutPart in slideMasterPart.SlideLayoutParts)
+            {
+                _ = GetOrAddSlideLayoutPart(_newDocument, slideLayoutPart, 1.0f);
+            }
+        }
+
+        // TODO: enumerate all images, media, master and layouts
+        _slideSize = presentation.Presentation.SlideSize;
+    }
+
+    private double GetScaleFactor(PresentationDocument sourceDocument)
+    {
+        var slideSize = sourceDocument.PresentationPart.Presentation.SlideSize;
+        var scaleFactorX = (double)_slideSize.Cx / slideSize.Cx;
+        var scaleFactorY = (double)_slideSize.Cy / slideSize.Cy;
+        return Math.Min(scaleFactorX, scaleFactorY);
+    }
+
+    // General function for handling images that tries to use an existing image if they are the same
+    private ImageData GetOrAddImageCopy(ImagePart oldImage)
+    {
+        return GetOrAddCachedMedia(new ImageData(oldImage));
+    }
+
+    // General function for handling media that tries to use an existing media item if they are the same
+    private MediaData GetOrAddMediaCopy(DataPart oldMedia)
+    {
+        return GetOrAddCachedMedia(new MediaData(oldMedia));
+    }
+
+    private T GetOrAddCachedMedia<T>(T contentData)
+        where T : ContentData
+    {
+        var duplicateItem = _mediaCache.FirstOrDefault(x => x.Compare(contentData));
+        if (duplicateItem != null)
+        {
+            return (T)duplicateItem;
+        }
+
+        _mediaCache.Add(contentData);
+        return contentData;
+    }
+
+    // General function for handling SlideMasterPart that tries to use an existing SlideMasterPart if they are the same
+    private SlideMasterData GetOrAddSlideMasterPart(
+        PresentationDocument presentationDocument,
+        SlideMasterPart slideMasterPart,
+        double scaleFactor
+    )
+    {
+        var slideMasterData = new SlideMasterData(slideMasterPart, scaleFactor);
+        foreach (var item in _slideMasterList)
+        {
+            if (item.CompareTo(slideMasterData) == 0)
+                return item;
+        }
+
+        if (!ReferenceEquals(presentationDocument, _newDocument))
+        {
+            var newSlideMasterPart = CopySlideMasterPart(slideMasterPart, scaleFactor);
+            slideMasterData = new SlideMasterData(newSlideMasterPart, 1.0);
+        }
+
+        _slideMasterList.Add(slideMasterData);
+        return slideMasterData;
+    }
+
+    // General function for handling SlideMasterPart that tries to use an existing SlideMasterPart if they are the same
+    private SlideLayoutData GetOrAddSlideLayoutPart(
+        PresentationDocument presentationDocument,
+        SlideLayoutPart slideLayoutPart,
+        double scaleFactor
+    )
+    {
+        var slideMasterData = GetOrAddSlideMasterPart(
+            presentationDocument,
+            slideLayoutPart.SlideMasterPart,
+            scaleFactor
+        );
+
+        var slideLayoutData = new SlideLayoutData(slideLayoutPart, scaleFactor);
+        foreach (var item in slideMasterData.SlideLayoutList)
+        {
+            if (item.CompareTo(slideLayoutData) == 0)
+                return item;
+        }
+
+        if (!ReferenceEquals(presentationDocument, _newDocument))
+        {
+            var newSlideLayoutPart = CopySlideLayoutPart(slideMasterData.Part, slideLayoutPart, scaleFactor);
+            slideLayoutData = new SlideLayoutData(newSlideLayoutPart, 1.0);
+        }
+
+        slideMasterData.SlideLayoutList.Add(slideLayoutData);
+        return slideLayoutData;
+    }
+}