# Cmd that finds the mains of an `mentity`
class CmdMains
	super CmdEntityList

	redef fun init_results do
		if results != null then return new CmdSuccess

		var res = super
		if not res isa CmdSuccess then return res
		var mentity = self.mentity.as(not null)
		var mentities = new Array[MEntity]

		if mentity isa MPackage then
			for mmodule in mentity.collect_all_mmodules(filter) do
				if mmodule_has_main(mmodule) then mentities.add mmodule
			end
		else if mentity isa MGroup then
			for mmodule in mentity.collect_all_mmodules(filter) do
				if mmodule_has_main(mmodule) then mentities.add mmodule
			end
		else if mentity isa MModule then
			if mmodule_has_main(mentity) then mentities.add mentity
		else
			return new WarningNoMains(mentity)
		end

		if mentities.is_empty then return new WarningNoMains(mentity)

		self.results = mentities
		return res
	end

	# Does `mmodule` has a `main` method?
	private fun mmodule_has_main(mmodule: MModule): Bool do
		for mclassdef in mmodule.collect_redef_mclassdefs(filter) do
			if mclassdef.name != "Sys" then continue
			for mpropdef in mclassdef.collect_redef_mpropdefs(filter) do
				if mpropdef.name == "main" then return true
			end
		end
		return false
	end
end