# Cmd that finds the nitc command related to an `mentity`
class CmdMainCompile
	super CmdEntity

	var file: nullable SourceFile = null

	var command: nullable String is lazy do
		var path = test_path(file)
		if path == null then return null
		return "nitc {path}"
	end

	redef fun init_command do
		var res = super
		if not res isa CmdSuccess then return res
		var mentity = self.mentity.as(not null)

		if mentity isa MModule then
			file = mmodule_main(mentity)
			if file == null then return new WarningNoMain(mentity)
		else
			return new WarningNoMain(mentity)
		end
		return res
	end

	# Does `mmodule` has a `main` method?
	private fun mmodule_main(mmodule: MModule): nullable SourceFile do
		for mclassdef in mmodule.mclassdefs do
			if mclassdef.name != "Sys" then continue
			for mpropdef in mclassdef.mpropdefs do
				if mpropdef.name == "main" then return mmodule.location.file
			end
		end
		return null
	end

	# Return the sourcefile path
	#
	# This method exists for the only purpose to be redefined by nitunit tests
	# to avoid path diffs.
	private fun test_path(file: nullable SourceFile): nullable String do
		if file == null then return null
		var base_path = mentity.as(MModule).mpackage.as(not null).location.file.as(not null).filename
		return file.filename.replace(base_path, "")
	end
end