Hi, I'm trying to extract a page from a PDF using pdfcpu and an io.ReadSeeker. When I use api.ReadContextFile(path) everything works correctly and ExtractPage succeeds. However, when I try to use api.ReadContext(readerSeeker, config) to read from an io.ReadSeeker, the context is created without error, but api.ExtractPage(ctx, pageNumber) fails with:

pdfcpu: page not found

I have confirmed that the readerSeeker is valid — other operations using the same readerSeeker work fine and detect the document correctly. The issue seems to be specific to how ReadContext sets up the context when using a ReadSeeker, particularly in relation to page access.

Here are the relevant code snippets:

conf := model.NewDefaultConfiguration()
ctx, err := api.ReadContext(readerSeeker, conf)
if err != nil {
    return fmt.Errorf("error creating context: %v\n", err)
}

Then later:

pageReader, err := api.ExtractPage(ctx, page)
if err != nil {
    fmt.Printf("Error splitting %s at page %d: %v\n", pdfName, page, err)
    continue
}

When using ReadContextFile(path) instead, the ExtractPage call works fine.

Is there a special consideration or additional step needed when using api.ReadContext with an io.ReadSeeker to properly initialize the context for page extraction?

Thanks in advance for any insights.