| repDir server changeHolder oldChanges newChanges stream installedMC installedVN |
Cursor wait showWhile:[

csBlock _ [:csName :block | changeHolder _ (ChangeSet respondsTo: #newChanges:)
						ifTrue: [ChangeSet]
						ifFalse: [Smalltalk].
	oldChanges _ (ChangeSet respondsTo: #current)
						ifTrue: [ChangeSet current]
						ifFalse: [Smalltalk changes].
	newChanges _ ChangeSet new name: csName.
	changeHolder newChanges: newChanges.
	[block value] ensure: [changeHolder newChanges: oldChanges]].

"Begin by toasting the old SMLoader"
(Smalltalk hasClassNamed: #SMLoader) ifTrue: [
	(Smalltalk at: #SMLoader) allInstances do: [:e | e myDependents: #(). e delete].
	csBlock value: 'SM1-loader-removal' value: [	
		SystemOrganization removeSystemCategory: 'SM-Loader']].

"Remember installed packages if we have them and toast old SM"
(Smalltalk hasClassNamed: #SMSqueakMap) ifTrue: [
	installed _ (Smalltalk at: #SMSqueakMap) default installedPackagesDictionary.
	csBlock value: 'SM1-removal' value: [

		"Have no idea why this does not work:"
		"SystemOrganization removeSystemCategory: 'SM-domain'"
		"Instead I use the older method:"
	(SystemOrganization superclassOrder: 'SM-domain') reverseDo: [:class | class removeFromSystem].
	SystemOrganization removeEmptyCategories
]].

installedVN _ false.
"Install first versions of VersionNumber for SM2 if it is missing, we can't rely on using old SM because it is removed"
(Smalltalk hasClassNamed: #VersionNumber) ifFalse: [
	ChangeSorter newChangesFromStream:
		((('http://map1.squeakfoundation.org/sm/package/35e02e3a-48e2-4843-94ee-e86d651aeafe/autoversion/1/downloadurl')
		asUrl retrieveContents content) asUrl retrieveContents content unzipped
		readStream)	
	named: (ChangeSet uniqueNameLike: 'VersionNumber').
	installedVN _ true].

"Load the new SM base, version 4, using available Monticello or MCInstaller, and installing version 1 of MCInstaller otherwise"
stream _ HTTPClient httpGet:
	('http://map1.squeakfoundation.org/sm/package/c4c13ea3-e376-42c7-8d9e-dc23b09f9f29/autoversion/4/downloadurl'
		asUrl retrieveContents content).

installedMC _ false.
(Smalltalk hasClassNamed: #MCMczReader)
	ifTrue: [(MCMczReader versionFromStream: stream) load "Using Monticello"]
	ifFalse: [
		"No Monticello installed, will use MCInstaller and install it first if needed"
		(Smalltalk hasClassNamed: #MczInstaller) ifFalse: [
			ChangeSorter
				newChangesFromStream:
					((('http://map1.squeakfoundation.org/sm/package/af9d090d-2896-4a4e-82d0-c61cf2fdf40e/autoversion/1/downloadurl')
				asUrl retrieveContents content) asUrl retrieveContents content unzipped
				readStream)
			named: (ChangeSet uniqueNameLike: 'MCInstaller').
			installedMC _ true].
		MczInstaller installStream: stream].

"This clears the default map, but keeps info on installed packages if there where any"
map _ (Smalltalk at: #SMSqueakMap) default.
installed ifNotNil: [map installedPackagesDictionary: installed].
"Remove old SM Package Loader, if present"
map clearInstalledPackageWithId: '047a3b12-7e52-4c5d-be8b-d06635fc4f1c'.
"Remove old SqueakMap Base, if present"
map clearInstalledPackageWithId: 'fffa45d3-2459-4b7d-b594-9cfae17c864d'.
"Remove old SqueakMap loadscript, if present"
map clearInstalledPackageWithId: '4f0b9db6-8add-43aa-8d6b-53e6a0ea8442'.

"Add that we now have version 4 of SqueakMap2 base, VersionNumber and MCInstaller installed"
map noteInstalledPackageWithId: 'c4c13ea3-e376-42c7-8d9e-dc23b09f9f29' autoVersion: '4'.
installedVN ifTrue: [map noteInstalledPackageWithId: '35e02e3a-48e2-4843-94ee-e86d651aeafe' autoVersion: '1'].
installedMC ifTrue: [map noteInstalledPackageWithId: 'af9d090d-2896-4a4e-82d0-c61cf2fdf40e' autoVersion: '1'].

"Make sure map is updated"
map loadUpdates.

"Install version 2 (bugfixed) of new SMLoader using SM2, hmmm, MCInstaller makes silly changesetnames..."
map installPackageWithId: '941c0108-4039-4071-9863-a8d7d2b3d4a3' autoVersion: '2'.

"Ok, open a new loader"
(Smalltalk at: #SMLoader) open].

"And kill this Process - This is because we don't want to return to the obsolete old SMLoader"
Project spawnNewProcessAndTerminateOld: true