use System.Diagnostics

class ObjcBackEnd inherits BackEnd

	cue init(compiler as Compiler)
		base.init(compiler)
		_name = 'objc'	
		_runTimeLibFileName = 'Cobra.Core.dll'
		_runTimeLibNativeSourceFileName = 'Native.m'  # back-end source file containing native code support for Cobra.Core

		_tagToTypeName = { 	# to-do
			'Object': '',
			'Type'	: '',
			}

	def makePhases(phases as IList<of Phase>) is override
		phases.add(GenerateObjcCodePhase(.compiler))
		phases.add(CompileObjcCodePhase(.compiler))

	def getRecommendedBuiltInType(parentNameSpace as NameSpace?, name as String) as String? is override
		n = nil to String?
		if parentNameSpace and parentNameSpace.fullName == '???'
			branch name
				on '???', n = 'bool'
				on '?? SByte',   n = 'int8'
				on '?? Byte',    n = 'uint8'
				on '?? Int16',   n = 'int16'
				on '?? UInt16',  n = 'uint16'
				on '?? Int32',   n = 'int32'
				on '?? UInt32',  n = 'uint32'
				on '?? Int64',   n = 'int64'
				on '?? UInt64',  n = 'uint64'
				on '?? Char',    n = 'char'
				on '?? Single',  n = 'float32'
				on '?? Double',  n = 'float'
				on '?? Decimal', n = 'decimal'
		return n

	def computeOutName as String is override
		return .compiler.computeOutNameObjc
		
	def genNativeModule(file as FileSpec, verbosity as int) as Module? is override
		m as Module?
		if file.path and file.path.endsWith('.objc') # ??
			if verbosity, print 'Noting  [file.path] as ObjCModule'  # extra space to line up with 'Parsing [filename]'
			assert false, 'Need code for an ObjCModule'	
			#m = ObjCModule(filename, verbosity)
		return m

	get baseExeName as String is override
		"""Resulting executable file name for compiled file(s) sans extension."""
		return .compiler.clrBaseExeFileName 	
	
	get fullExeName as String is override
		"""Resulting full executable file name (pathname+extn) for compiled file(s)."""
		return .compiler.clrFullExeFileName

	def setupRunProcess(baseExe as String, fullExe as String) as Process is override
		p = Process()
		p.startInfo.fileName = fullExe
		return p
		
	def setDefaultUseDirectives(ns as NameSpace) is override
		useToken = Token('(implicit)', 1, 1, 1, 'USE', 'use', nil)
		# these arent correct for ObjC but are here as a placeholder/reminder
		ns.addUseDirective(UseDirective(useToken, ['System']))
		ns.addUseDirective(UseDirective(useToken, ['System', 'Collections', 'Generic']))
		ns.addUseDirective(UseDirective(useToken, ['System', 'IO']))
		ns.addUseDirective(UseDirective(useToken, ['System', 'Text']))
		ns.addUseDirective(UseDirective(useToken, ['Cobra', 'Core']))
	
	def fixLibExtension(libRef as String) as String is override
		"""
		Augment given lib reference string with .dll backend extension if not already have one
		"""
		or require libRef.length
		and ensure result.endsWith('.dll')
		if not libRef.endsWith('.dll'), libRef += '.dll'
		return libRef
	
	def loadLibReference(reference as String) as String? is override
		return nil	# TODO
	
	def readSystemTypes is override
		pass
	
	def fixMemberSigs is override
		pass

	def installNativeMethods(box as Box, nativeType as NativeType) is override
		pass

	def cobraNameForNativeBoxName(nativeBoxName as String) as String is override
		return nativeBoxName # TODO
		
	def isRunnableFile(fullExeFileName as String) as bool is override
		return true # may need extending

	# Types
	get objectTypeProxy as AbstractTypeProxy  is override
		"""Type proxy for BE root of Object hierarchy."""
		return ClrTypeProxy(Object)  # Tmp pending ObjcTypeProxy
			
	get typeTypeProxy  as AbstractTypeProxy  is override
		"""Type proxy for BE notion of a class describing a Type."""
		return ClrTypeProxy(Type)  # Tmp pending ObjcTypeProxy
		
	def nativeTypeProxy(type as NativeType) as NativeTypeProxy  is override
		assert false, 'ObjcBackEnd ObjcNativeTypeProxy NYI'
		return ClrTypeProxy(type)  # Tmp pending ObjcTypeProxy
	
	def nativeType(type as dynamic) as NativeType  is override
		assert false, 'ObjcBackEnd ObjcNativeType NYI'
		return ClrNativeType(type) # Tmp pending ObjcNativeType
	
	def nativeTypeByName(qualifiedName as String) as NativeType is override
		assert false, 'ObjcBackEnd ObjcNativeType and objcTypeByName NYI'
		return ClrNativeType(.compiler.clrTypeByName(qualifiedName))
	
	def prepSystemObjectClass(box as Box)  is override
		pass 	#box.prepSystemObjectClassObjc
		
	def scanGenericArgs(box as Box)	 is override
		pass 	# box.scanGenericArgsObjc
		
	def scanNativeType(box as Box)	 is override
		pass 	# box.scanNativeTypeObjc

	def scanNativeType(edcl as EnumDecl)	 is override
		pass 	# edcl.scanNativeTypeObjc
		
	def setUnderlyingType(edcl as EnumDecl)	 is override
		pass # edecl.setUnderlyingTypeObjc

	# implement these if need override
	#def determineExtnNativeType(extn as Extension, nativeType as NativeType) as NativeType
	#	return extn.objcExtnNativeType(nativeType)

	#def handleNameSpaceNameCollision(ns as NameSpace, token as IToken, name as String) as NameSpace is override

	def getEnumeratorMember(box as Box) as IMember? is override
		""" Find iterator method member in given Box."""
		return nil 	#box.getIteratorMemberObjc
		
	def getEnumeratorMemberType(box as Box, rt as IType) as IType? is override
		"""Return type from lookup of iterator 'next' field in given Box."""
		return nil #	box.getIteratorNextTypeObjc(rt)
	
	def validatePrintDestType(t as IType, s as Stmt) is override
		"""Validate that the given Type is a valid destination for a print statement redirection."""
		pass
		
		
class GenerateObjcCodePhase inherits Phase

	cue init(c as Compiler)
		base.init(c)

	get description as String is override
		return 'Generating Objective-C code'

	def innerRun is override
		c = .compiler
		c.writeObjc  # extension method
		if c.willWriteTestInvocation
			c.writeObjcTestInvocation


class CompileObjcCodePhase inherits Phase

	cue init(c as Compiler)
		base.init(c)

	get description as String is override
		return 'Compiling Objective-C code'

	def innerRun is override
		.compiler.compileObjc