from pathlib              import Path
from unittest             import TestCase

import pyGHDL.libghdl     as libghdl
from pyGHDL.libghdl       import name_table, files_map, errorout_console
from pyGHDL.libghdl.vhdl  import nodes, sem_lib


if __name__ == "__main__":
	print("ERROR: you called a testcase declaration file as an executable module.")
	print("Use: 'python -m unitest <testcase module>'")
	exit(1)


class Instantiate(TestCase):
	_root = Path(__file__).resolve().parent.parent
	_filename : Path = _root / "SimpleEntity.vhdl"

	@staticmethod
	def getIdentifier(node):
		"""Return the Python string from node :obj:`node` identifier"""
		return name_table.Get_Name_Ptr(nodes.Get_Identifier(node))

	def test_InitializeGHDL(self) -> None:
		"""Initialization: set options and then load libaries"""
		libghdl.initialize()

		# Print error messages on the console.
		errorout_console.Install_Handler()

		# Set options. This must be done before analyze_init()
		libghdl.set_option("--std=08")

		# Finish initialization. This will load the standard package.
		if libghdl.analyze_init_status() != 0:
			self.fail("libghdl initialization error")

		# Load the file
		file_id = name_table.Get_Identifier(str(self._filename))
		sfe = files_map.Read_Source_File(name_table.Null_Identifier, file_id)
		if sfe == files_map.No_Source_File_Entry:
			self.fail("Cannot read file '{!s}'".format(self._filename))

		# Parse
		file = sem_lib.Load_File(sfe)

		# Display all design units
		designUnit = nodes.Get_First_Design_Unit(file)
		while designUnit != nodes.Null_Iir:
			libraryUnit = nodes.Get_Library_Unit(designUnit)

			if nodes.Get_Kind(libraryUnit) == nodes.Iir_Kind.Entity_Declaration:
				entityName = self.getIdentifier(libraryUnit)
				self.assertEqual(entityName, "e1", "expected entity name 'e1', got '{}'".format(entityName))

			elif nodes.Get_Kind(libraryUnit) == nodes.Iir_Kind.Architecture_Body:
				architectureName = self.getIdentifier(libraryUnit)
				self.assertEqual(architectureName, "behav", "expected architecture name 'behav', got '{}'".format(architectureName))

			else:
				self.fail("Unknown unit.")

			designUnit = nodes.Get_Chain(designUnit)