public Dictionary <int, ExportEntry> ExportDeltas = new Dictionary <int, ExportEntry>(); //includes header and data
/// <summary>
/// Compares two packages - vanilla vs modified - and returns the result. This MUST be a vanilla file as vanilla constraints are assumed.
/// </summary>
/// <param name="ancestorPackage">VANILLA FILE</param>
/// <param name="modifiedPackage"></param>
/// <returns></returns>
public static PackageDelta CalculateDelta(IMEPackage ancestorPackage, IMEPackage modifiedPackage)
{
PackageDelta delta = new PackageDelta();
#region Exports Comparison
{
int numExportsToEnumerate = ancestorPackage.ExportCount;
for (int i = 0; i < numExportsToEnumerate; i++)
{
ExportEntry exp1 = ancestorPackage.Exports[i];
ExportEntry exp2 = modifiedPackage.Exports[i];
//make data offset and data size the same, as the exports could be the same even if it was appended later.
//The datasize being different is a data difference not a true header difference so we won't list it here.
byte[] header1 = exp1.Header.TypedClone();
byte[] header2 = exp2.Header.TypedClone();
Buffer.BlockCopy(BitConverter.GetBytes((long)0), 0, header1, 32, sizeof(long)); //zero out offset
Buffer.BlockCopy(BitConverter.GetBytes((long)0), 0, header2, 32, sizeof(long)); //zero out offset
//if (!StructuralComparisons.StructuralEqualityComparer.Equals(header1, header2))
if (!header1.SequenceEqual(header2))
{
delta.ExportDeltas[i] = modifiedPackage.Exports[i];
continue;
}
if (!exp1.Data.SequenceEqual(exp2.Data))
{
delta.ExportDeltas[i] = modifiedPackage.Exports[i];
}
}
if (modifiedPackage.ExportCount > ancestorPackage.ExportCount)
{
for (int i = ancestorPackage.ExportCount; i < modifiedPackage.ExportCount; i++)
{
//added exports.
delta.ExportDeltas[i] = modifiedPackage.Exports[i];
}
}
}
#endregion
#region Imports
{
int numImportsToEnumerate = ancestorPackage.ImportCount;
for (int i = 0; i < numImportsToEnumerate; i++)
{
ImportEntry imp1 = ancestorPackage.Imports[i];
ImportEntry imp2 = modifiedPackage.Imports[i];
if (!imp1.Header.SequenceEqual(imp2.Header))
{
delta.ImportDeltas[i] = imp2; //0-based index
}
}
if (modifiedPackage.ImportCount > ancestorPackage.ImportCount)
{
//added imports
for (int i = ancestorPackage.ImportCount; i < modifiedPackage.ImportCount; i++)
{
delta.ImportDeltas[i] = modifiedPackage.Imports[i]; //0-based index
}
}
}
#endregion
#region Names
{
//you cannot delete names in packages.
//as such target will always have at least same amount of names as vanilla.
int numNamesToEnumerate = ancestorPackage.NameCount;
for (int i = 0; i < numNamesToEnumerate; i++)
{
var name1 = ancestorPackage.Names[i];
var name2 = modifiedPackage.Names[i];
if (!name1.Equals(name2, StringComparison.InvariantCultureIgnoreCase))
{
delta.NameDeltas[i] = name2; // i => name 2
}
}
if (modifiedPackage.NameCount > ancestorPackage.NameCount)
{
for (int i = ancestorPackage.NameCount; i < modifiedPackage.NameCount; i++)
{
//added names.
delta.NameDeltas[i] = modifiedPackage.Names[i];
}
}
}
#endregion
return(delta);
}
public static bool AttemptMerge(MEPackage vanillaPackage, MEPackage modifiedVanillaPackage, MEPackage targetPackage)
{
PackageDelta vanillaToModifiedDelta = PackageDelta.CalculateDelta(vanillaPackage, modifiedVanillaPackage);
PackageDelta vanillaToTargetDelta = PackageDelta.CalculateDelta(vanillaPackage, targetPackage);
string loggingPrefix = targetPackage.FilePath == null ? targetPackage.FileSourceForDebugging : Path.GetFileName(targetPackage.FilePath);
//Check merge conditions
var nameConflicts = vanillaToModifiedDelta.NameDeltas.Keys.Intersect(vanillaToTargetDelta.NameDeltas.Keys).ToList();
var importConflicts = vanillaToModifiedDelta.ImportDeltas.Keys.Intersect(vanillaToTargetDelta.ImportDeltas.Keys).ToList();
var exportConflicts = vanillaToModifiedDelta.ExportDeltas.Keys.Intersect(vanillaToTargetDelta.ExportDeltas.Keys).ToList();
Log.Information($@"[{loggingPrefix}] Performing three way merge pre-check");
//Name deltas
if (nameConflicts.Count > 0)
{
//need to check if the conflicts result in same value, in this case it would not be a conflict.
foreach (int nameIndex in nameConflicts)
{
var modifiedName = modifiedVanillaPackage.Names[nameIndex];
var targetName = targetPackage.Names[nameIndex];
if (modifiedName != targetName)
{
//Differing names in same spots.
Log.Information($@"[{loggingPrefix}] Cannot merge files: Name index {nameIndex} is different between modified and target.");
return(false);
}
}
}
if (importConflicts.Count > 0)
{
//todo
}
if (exportConflicts.Count > 0)
{
//hmm... this will be a tough one.
foreach (int exportTableIndex in exportConflicts)
{
//we will have to check sizes if we ever hope to have way to merge this
var modifiedData = modifiedVanillaPackage.Exports[exportTableIndex].Data;
var targetData = targetPackage.Exports[exportTableIndex].Data;
if (!modifiedData.SequenceEqual(targetData))
{
Log.Information($@"[{loggingPrefix}] Cannot merge files: Export table index {exportTableIndex} data is different between modified and target.");
return(false);
}
//We will have to ignore size here somehow...
//var modifiedHeader = modifiedVanillaPackage.Exports[exportTableIndex].Header;
//var targetHeader = targetPackage.Exports[exportTableIndex].Header;
}
}
//Merge is OK to perform
//Apply vanilla to modified delta to target package
foreach (var nameDelta in vanillaToModifiedDelta.NameDeltas)
{
if (nameDelta.Key >= targetPackage.NameCount)
{
//add it
Log.Information($@"[{loggingPrefix}] Adding name {nameDelta.Value}");
targetPackage.addName(nameDelta.Value);
}
else
{
Log.Information($@"[{loggingPrefix}] Updating name index {nameDelta.Key} to {nameDelta.Value}");
targetPackage.replaceName(nameDelta.Key, nameDelta.Value);
}
}
foreach (var exportDelta in vanillaToModifiedDelta.ExportDeltas)
{
if (exportDelta.Key >= targetPackage.ExportCount)
{
//add it
Log.Information($@"[{loggingPrefix}] Adding export {exportDelta.Value.GetInstancedFullPath}");
targetPackage.addExport(exportDelta.Value); //not sure if this is possible
}
else
{
//gonna need this reviewed, not entirely sure this is OK to do
Log.Information($@"[{loggingPrefix}] Updating export {exportDelta.Value.GetInstancedFullPath}");
targetPackage.Exports[exportDelta.Key].Data = exportDelta.Value.Data;
targetPackage.Exports[exportDelta.Key].Header = exportDelta.Value.Header;
}
}
foreach (var importDelta in vanillaToModifiedDelta.ImportDeltas)
{
if (importDelta.Key >= targetPackage.ImportCount)
{
//add it
Log.Information($@"[{loggingPrefix}] Adding import {importDelta.Value.GetInstancedFullPath}");
targetPackage.addImport(importDelta.Value); //not sure if this is possible
}
else
{
Log.Information($@"[{loggingPrefix}] Updating import {importDelta.Value.GetInstancedFullPath}");
//gonna need this reviewed, not entirely sure this is OK to do
//targetPackage.Imports[importDelta.Key].Data = importDelta.Value.Data;
targetPackage.Imports[importDelta.Key].Header = importDelta.Value.Header;
}
}
Log.Information($@"[{loggingPrefix}] Finished three way merge");
return(true);
}
