/// <summary>
/// Usually we expect that a file at the same path but with extension .svg will
/// be found and returned. Failing this we try for one ending in .png. If this still fails we
/// start a process to generate an image from the template page content.
/// </summary>
/// <returns>Should always return a valid image path, unless we really can't come up with an image at all.</returns>
private string FindOrGenerateThumbnail(string expectedPathOfThumbnailImage)
{
var localPath = AdjustPossibleLocalHostPathToFilePath(expectedPathOfThumbnailImage);
var svgpath = Path.ChangeExtension(localPath, "svg");
if (RobustFile.Exists(svgpath))
{
return(svgpath);
}
var pngpath = Path.ChangeExtension(localPath, "png");
bool mustRegenerate = false;
if (RobustFile.Exists(pngpath))
{
var f = new FileInfo(pngpath);
if (f.IsReadOnly)
{
return(pngpath); // it's locked, don't try and replace it
}
if (!IsPageTypeFromCurrentBook(localPath))
{
return(pngpath);
}
mustRegenerate = true; // prevent thumbnailer using cached (obsolete) image
}
var altpath = GetAlternativeWritablePath(pngpath);
if (RobustFile.Exists(altpath))
{
if (!IsPageTypeFromCurrentBook(localPath))
{
return(altpath);
}
mustRegenerate = true; // prevent thumbnailer using cached (obsolete) image
}
// We don't have an image, or we want to make a fresh one
var templatesDirectoryInTemplateBook = Path.GetDirectoryName(expectedPathOfThumbnailImage);
var bookPath = Path.GetDirectoryName(templatesDirectoryInTemplateBook);
var templateBook = _bookFactory(new BookInfo(bookPath, false), _storageFactory(bookPath));
//note: the caption is used here as a key to find the template page.
var caption = Path.GetFileNameWithoutExtension(expectedPathOfThumbnailImage).Trim();
var isLandscape = caption.EndsWith("-landscape"); // matches string in page-chooser.ts
if (isLandscape)
{
caption = caption.Substring(0, caption.Length - "-landscape".Length);
}
var isSquare = caption.EndsWith("-square");
if (isSquare)
{
caption = caption.Substring(0, caption.Length - "-square".Length);
}
// The Replace of & with + corresponds to a replacement made in page-chooser.ts method loadPagesFromCollection.
// The Trim is needed because template may now be created by users editing the pageLabel div, and those
// labels typically include a trailing newline.
IPage templatePage = templateBook.GetPages().FirstOrDefault(page => page.Caption.Replace("&", "+").Trim() == caption);
if (templatePage == null)
{
templatePage = templateBook.GetPages().FirstOrDefault(); // may get something useful?? or throw??
}
Image thumbnail = _thumbNailer.GetThumbnailForPage(templateBook, templatePage, isLandscape, isSquare, mustRegenerate);
// lock to avoid BL-3781 where we got a "Object is currently in use elsewhere" while doing the Clone() below.
// Note: it would appear that the clone isn't even needed, since it was added in the past to overcome this
// same contention problem (but, in hindsight, only partially, see?). But for some reason if we just lock the image
// until it is saved, we get all gray rectangles. So for now, we just quickly do the clone and unlock.
var resultPath = "";
Bitmap clone;
// Review: the coarse lock(SyncObj) in BloomServer.ProcessRequest() may have removed the need for this finer grained lock.
lock (thumbnail)
{
clone = new Bitmap((Image)thumbnail.Clone());
}
using (clone)
{
try
{
//if the directory doesn't exist in the template's directory, make it (i.e. "templates/").
Directory.CreateDirectory(templatesDirectoryInTemplateBook);
//save this thumbnail so that we don't have to generate it next time
clone.Save(pngpath);
resultPath = pngpath;
}
catch (Exception)
{
var folder = Path.GetDirectoryName(altpath);
Directory.CreateDirectory(folder);
clone.Save(altpath);
resultPath = altpath;
}
}
return(resultPath);
}
/// <summary>
/// Usually we expect that a file at the same path but with extension .svg will
/// be found and returned. Failing this we try for one ending in .png. If this still fails we
/// start a process to generate an image from the template page content.
/// </summary>
/// <param name="expectedPathOfThumbnailImage"></param>
/// <returns>Should always return true, unless we really can't come up with an image at all.</returns>
private string FindOrGenerateThumbnail(string expectedPathOfThumbnailImage)
{
var localPath = AdjustPossibleLocalHostPathToFilePath(expectedPathOfThumbnailImage);
var svgpath = Path.ChangeExtension(localPath, "svg");
if (RobustFile.Exists(svgpath))
{
return(svgpath);
}
var pngpath = Path.ChangeExtension(localPath, "png");
bool mustRegenerate = false;
if (RobustFile.Exists(pngpath))
{
var f = new FileInfo(pngpath);
if (f.IsReadOnly)
{
return(pngpath); // it's locked, don't try and replace it
}
//If there is no svg, then we assume the we are using a generated image.
//If the book we want a thumbnail from is the one is the one we are currently editing,
//then the thumbnail we generated last time might not reflect how the page is laid out
//now. So in that case we ignore the existing png thumbnail (and any cached version
//of it we previously saved) and make a new one. Bloom saves the current page
//before invoking AddPage, so the file contains the right content for making the new one.
var testLocalPath = localPath.Replace("/", "\\");
var testFolderPath = _bookSelection.CurrentSelection.FolderPath.Replace("/", "\\");
if (Platform.IsWindows)
{
// Not a formality, since localPath comes from GetBookTemplatePaths and has been
// forced to LC on Windows, while the book's FolderPath has not.
testLocalPath = testLocalPath.ToLowerInvariant();
testFolderPath = testFolderPath.ToLowerInvariant();
}
if (!testLocalPath.Contains(testFolderPath))
{
return(pngpath);
}
mustRegenerate = true; // prevent thumbnailer using cached (obsolete) image
}
// We don't have an image, or we want to make a fresh one
var templatesDirectoryInTemplateBook = Path.GetDirectoryName(expectedPathOfThumbnailImage);
var bookPath = Path.GetDirectoryName(templatesDirectoryInTemplateBook);
var templateBook = _bookFactory(new BookInfo(bookPath, false), _storageFactory(bookPath));
//note: the caption is used here as a key to find the template page.
var caption = Path.GetFileNameWithoutExtension(expectedPathOfThumbnailImage).Trim();
var isLandscape = caption.EndsWith("-landscape"); // matches string in page-chooser.ts
if (isLandscape)
{
caption = caption.Substring(0, caption.Length - "-landscape".Length);
}
// The Replace of & with + corresponds to a replacement made in page-chooser.ts method loadPagesFromCollection.
// The Trim is needed because template may now be created by users editing the pageLabel div, and those
// labels typically include a trailing newline.
IPage templatePage = templateBook.GetPages().FirstOrDefault(page => page.Caption.Replace("&", "+").Trim() == caption);
if (templatePage == null)
{
templatePage = templateBook.GetPages().FirstOrDefault(); // may get something useful?? or throw??
}
Image thumbnail = _thumbNailer.GetThumbnailForPage(templateBook, templatePage, isLandscape, mustRegenerate);
// lock to avoid BL-3781 where we got a "Object is currently in use elsewhere" while doing the Clone() below.
// Note: it would appear that the clone isn't even needed, since it was added in the past to overcome this
// same contention problem (but, in hindsight, only partially, see?). But for some reason if we just lock the image
// until it is saved, we get all gray rectangles. So for now, we just quickly do the clone and unlock.
var resultPath = "";
Bitmap clone;
// Review: the coarse lock(SyncObj) in EnhancedImageServer.ProcessRequest() may have removed the need for this finer grained lock.
lock (thumbnail)
{
clone = new Bitmap((Image)thumbnail.Clone());
}
using (clone)
{
try
{
//if the directory doesn't exist in the template's directory, make it (i.e. "templates/").
Directory.CreateDirectory(templatesDirectoryInTemplateBook);
//save this thumbnail so that we don't have to generate it next time
clone.Save(pngpath);
resultPath = pngpath;
}
catch (Exception)
{
using (var file = new TempFile())
{
clone.Save(file.Path);
resultPath = file.Path;
}
}
}
return(resultPath);
}
