/// <summary>
/// Squashes the given changesets into one that has the same effect.
/// </summary>
public static OsmChange Squash(this IEnumerable <OsmChange> changes)
{
var deletions = new Dictionary <OsmGeoVersionKey, OsmGeo>();
var modifications = new Dictionary <OsmGeoVersionKey, OsmGeo>();
var creations = new Dictionary <OsmGeoVersionKey, OsmGeo>();
foreach (var change in changes)
{
if (change.Create != null)
{
foreach (var create in change.Create)
{ // just add all creates as normal.
creations[new OsmGeoVersionKey(create)] = create;
}
}
if (change.Modify != null)
{
foreach (var mod in change.Modify)
{
OsmGeo creationOfMod;
var key = new OsmGeoVersionKey(mod);
if (creations.TryGetPreviousVersion(key, out creationOfMod))
{ // don't modify a new creation, create it properly once.
creations.Remove(new OsmGeoVersionKey(creationOfMod));
creations[key] = mod;
}
else
{ // add to modifications as normal.
modifications[key] = mod;
}
}
}
if (change.Delete != null)
{
foreach (var del in change.Delete)
{
var key = new OsmGeoVersionKey(del);
if (creations.ContainsKey(key))
{ // don't delete after create, just don't create.
creations.Remove(key);
}
else
{ // add delete as normal.
deletions[new OsmGeoVersionKey(del)] = del;
}
}
}
}
return(new OsmChange()
{
Create = creations.Values.ToArray(),
Delete = deletions.Values.ToArray(),
Modify = modifications.Values.ToArray(),
Generator = "OsmSharp",
Version = 6
});
}
public void OsmGeoVersionKey_Nodes_CompareVersion()
{
var n1 = new OsmGeoVersionKey(OsmGeoType.Node, 42, 0);
var n2 = new OsmGeoVersionKey(OsmGeoType.Node, 42, 1);
Assert.AreEqual(-1, n1.CompareTo(n2));
Assert.AreEqual(1, n2.CompareTo(n1));
}
public void OsmGeoVersionKey_NodeAndWay_CompareId()
{
var n1 = new OsmGeoVersionKey(OsmGeoType.Node, 42, 0);
var n2 = new OsmGeoVersionKey(OsmGeoType.Way, 0, 0);
Assert.AreEqual(-1, n1.CompareTo(n2));
Assert.AreEqual(1, n2.CompareTo(n1));
}
/// <summary>
/// Tries to get a previous version in the given dictionary.
/// </summary>
private static bool TryGetPreviousVersion(this Dictionary <OsmGeoVersionKey, OsmGeo> data, OsmGeoVersionKey key,
out OsmGeo result)
{
var previous = key;
result = null;
while (!data.TryGetValue(previous, out result))
{
previous = previous.Previous;
if (previous == null)
{
return(false);
}
}
return(true);
}
/// <summary>
/// Returns true if the given key is in the dictionary.
/// </summary>
private static bool ContainsPreviousVersion(this Dictionary <OsmGeoVersionKey, OsmGeo> data, OsmGeoVersionKey key)
{
OsmGeo result;
return(data.TryGetPreviousVersion(key, out result));
}
