#!/usr/bin/env python3
# SPDX-License-Identifier: MIT
# Copyright (c) 2023 John Watts and the LuminaSensum contributors

## PARSER

class ASTStatement():
	def __repr__(self):
		return 'ASTStatement'

class ASTFunction():
	def __init__(self, name, statements):
		self.name = name
		self.statements = statements

	def __repr__(self):
		return 'ASTFunction(name="%s", statements="%s")' % (self.name, self.statements)

def tokenize(code):
	line = []
	lines = []
	tok = ""
	for c in code.strip():
		if c == ' ':
			line.append(tok)
			tok = ""
		elif c == '\n':
			line.append(tok)
			lines.append(line)
			line = []
			tok = ""
		else:
			tok += c
	line.append(tok)
	lines.append(line)
	return lines

def parse_statement(lines):
	line = lines[0]
	instr = line[0]
	if instr == "Set":
		print("SET")
		# ASTSet
	elif instr == "Return":
		print("RETURN")
		# ASTReturn
	else:
		print("COMMAND")
		# ASTCommand
	statement = ASTStatement()
	return (statement, lines[1:])

def parse_function(lines):
	line = lines[0]
	lines = lines[1:]
	if len(line) != 2 or line[0] != "Function":
		print("not a function? line: %s" % (' '.join(line)))
		return (None, [])
	name = line[1]
	statements = []
	print(lines)
	while len(lines) != 0:
		first_word = lines[0][0]
		if first_word == "EndFunction":
			lines = lines[1:]
			break
		(statement, lines) = parse_statement(lines)
		if statement == None:
			return None
		else:
			statements.append(statement)
	func = ASTFunction(name, statements)
	return (func, lines)

def parse_toplevel(lines):
	ast = []
	while len(lines) != 0:
		(func, lines) = parse_function(lines)
		if func == None:
			return None
		else:
			ast.append(func)
	return ast

code = """
Function MakeNumber
Set Halfish To 618
Set Double To Halfish Add Halfish
Set Final To Out Minus 2
Return Final
EndFunction
"""

lines = tokenize(code)
ast = parse_toplevel(lines)
print(ast)