/// <summary>
/// Compares the specified pages and returns an object detailing the differences.
/// </summary>
/// <param name="pageA">The first page.</param>
/// <param name="pageB">The second page.</param>
/// <returns>An object of type Comparison.</returns>
private Comparison ComputeDiff(Scrape pageA, Scrape pageB)
{
Comparison comparison;
using (Image pageScreenshotA = ImageUtil.Base64ToImage(pageA.Screenshot), pageScreenshotB = ImageUtil.Base64ToImage(pageB.Screenshot))
{
// Html diff
var htmlDiff = GetHtmlDiffReport(pageA.Html, pageB.Html);
// Pixel diff
var pixelDiff = PixelDiff(pageScreenshotA, pageScreenshotB);
// Match up elements
var largestDiagonal = (decimal)Math.Max(
Hypotenuse(pageScreenshotA.Width, pageScreenshotA.Height),
Hypotenuse(pageScreenshotB.Width, pageScreenshotB.Height));
CorrespondingElements(pageA, pageB, largestDiagonal);
var matches = pageA.Elements.Where(e => e.CorrespondingScrapedElement != null).ToArray();
// Get changes
var changedItems = GetChanges(matches, pageScreenshotA, pageScreenshotB, pageA, pageB).ToArray();
var unchanged = matches.Count(m => !m.HasChanges);
var changed = matches.Where(m => m.HasChanges).ToArray();
var deleted = pageA.Elements.Where(e => e.CorrespondingScrapedElement == null).ToArray();
var added = pageB.Elements.Where(e => e.CorrespondingScrapedElement == null).ToArray();
var removedItems = deleted.Select(e => GetElementData(pageScreenshotA, e, pageA)).ToArray();
var addedItems = added.Select(e => GetElementData(pageScreenshotB, e, pageB)).ToArray();
// Compute overall percentages
var total = (added.Length + deleted.Length + unchanged + changed.Length) * 100;
var addedDeleted = (added.Length + deleted.Length) * 100;
var cssChangePercentage = TotalChangePercentage(total, changedItems.Sum(i => i.CssPercentageChange), addedDeleted);
var textChangePercentage = TotalChangePercentage(total, changedItems.Sum(i => i.TextPercentageChange), addedDeleted);
var overallElementPositionChangePercentage = TotalChangePercentage(total, changedItems.Sum(i => i.LocationPercentageChange), addedDeleted);
var htmlPercentChanged = TotalChangePercentage(total, changedItems.Sum(i => i.HtmlPercentageChange), addedDeleted);
// Create Added/Changed elements and Deleted elements images
var outlinedImages = OutlinedImagesAsBase64(pageScreenshotA, pageScreenshotB, added, deleted, changedItems).ToArray();
var scrapeHybridA = AssembleScrapeHybrid(pageA, true);
var scrapeHybridB = AssembleScrapeHybrid(pageB, false);
comparison = new Comparison
{
Scrapes = new[] { scrapeHybridA, scrapeHybridB },
Result = new PageResult
{
HtmlDiff = htmlDiff,
Pixels = pixelDiff,
ChangedItems = changedItems,
AddedItems = addedItems,
RemovedItems = removedItems,
UnchangedItems = unchanged,
CssChangePercentage = cssChangePercentage,
TextChangePercentage = textChangePercentage,
OverallElementPositionChangePercentage = overallElementPositionChangePercentage,
Html = new HtmlResult { PercentChanged = htmlPercentChanged, Images = outlinedImages },
}
};
}
return comparison;
}
public Comparison FakeComparison(FakeComparisonParams fakeComparisonParams)
{
var hybrid1 = new ScrapeHybrid();
var hybrid2 = new ScrapeHybrid();
var result = new PageResult();
if (fakeComparisonParams.ScrapeHybrids == null)
{
var idString = new StringAsReference {Value = "a1b2c3d4e5f6a7b8c9d1e"};
var htmlString = new StringAsReference {Value = ""};
hybrid1 = new ScrapeHybrid
{
ExcludeJquerySelector = @"''",
IncludeJquerySelector = @"'body*'",
Script = "",
BoundingRectangle = new Rectangle(0, 0, 0, 0),
Description = "",
IdString = idString,
Path = null,
Resources = null,
Html = htmlString,
Url = "http://www.google.com",
Screenshot = null,
ViewportSize = new Size(800, 600),
Browser = "Chrome",
BrowserVersion = "10",
TimeStamp = DateTime.Now,
Platform = "Windows",
Cookies = null
};
hybrid2 = new ScrapeHybrid
{
ExcludeJquerySelector = @"''",
IncludeJquerySelector = @"'body*'",
Script = "",
BoundingRectangle = new Rectangle(10, 10, 10, 10),
Description = "",
IdString = idString,
Path = null,
Resources = null,
Html = htmlString,
Url = "http://www.ancestry.com",
Screenshot = null,
ViewportSize = new Size(800, 600),
Browser = "FireFox",
BrowserVersion = "10",
TimeStamp = DateTime.Now.AddDays(10),
Platform = "Windows",
Cookies = null
};
}
if (fakeComparisonParams.Result == null)
{
result = FakePageResult(new FakeComparisonResult());
}
var fakedComparison = new Comparison
{
Scrapes = fakeComparisonParams.ScrapeHybrids ?? new[] { hybrid1, hybrid2 },
Id = fakeComparisonParams.ObjectId ?? new ObjectId("555b77b99b111d2aa4b33333"),
Path = fakeComparisonParams.Path ?? new StringAsReference(),
Result = fakeComparisonParams.Result ?? result
};
return fakedComparison;
}
