#!/usr/bin/env python3

# Import local files
from whitespace import *
from command import *
from util import *
import builtin_commands

from panflute import *
import re
import sys
from typing import List

from mj_show import show

flags = ["dog"]
commands = []

def executeCommand(source: Code, element: Element) -> List[Element]:
	mode = 'empty'
	text = ""
	content = []
	def print(s: str):
		if mode == 'elements':
			raise SyntaxError("Cannot use `print` and `appendChild` in one command at the same time.")
		mode = 'text'
		text += s
	
	def println(s: str):
		print(s+"\n")

	def appendChild(e: Element):
		if mode == 'text':
			raise SyntaxError("Cannot use `print` and `appendChild` in one command at the same time.")
		mode = 'elements'
		content.append(e)

	exec(source)

	if mode == 'text':
		return convert_text(text)
	if mode == 'elements':
		return content

	



def transform(e: Element) -> Element: # Returns next sibling element to transform
	"""Transform the AST, making format-agnostic changes."""
	
	if isinstance(e, Whitespace) and bavlna(e):
		e = replaceEl(e, NBSP())

	if hasattr(e, "attributes"):
		# `if` attribute. Only show this element if flag is set.
		if "if" in e.attributes:
			if not e.attributes["if"] in flags:
				deleteEl(e)
				return
		# `ifn` attribute. Only show this element if flag is NOT set
		if "ifn" in e.attributes:
			if e.attributes["ifn"] in flags:
				deleteEl(e)
				return
		
		# `c` attribute. Execute a command with the name saved in this attribute.
		if (isinstance(e, Div) or isinstance(e, Span)) and "c" in e.attributes:
			if isinstance(e, Div):
				e = replaceEl(e, MultilineCommand(*e.content, identifier=e.identifier, classes=e.classes, attributes=e.attributes))
			else:
				e = replaceEl(e, InlineCommand(*e.content, identifier=e.identifier, classes=e.classes, attributes=e.attributes))
	
	
	# Execute python code inside source code block
	if isinstance(e, CodeBlock) and hasattr(e, "classes") and "python" in e.classes and "run" in e.classes:
		exec(e.text)
		deleteEl(e)
		return
	
	
	if isinstance(e, CodeBlock) and hasattr(e, "classes") and "python" in e.classes and hasattr(e, attributes):
		if "define" in e.attributes:
			if not e.attributes["define"] in commands:
				commands[e.attributes["define"]] = compile(e.text, '<string>', 'exec')
			else:
				raise NameError(f"Command already defined: '{e.attributes['define']}'")
		if "redefine" in e.attributes:
			commands[e.attributes["redefine"]] = compile(e.text, '<string>', 'exec')
	
	# Handle special command shorthand [!commandname]{}
	if isinstance(e, Span) and len(e.content) == 1 and isinstance(e.content[0], Str) and re.match(r"^![\w.]+$", e.content[0].text):
		e = replaceEl(e, InlineCommand(identifier=e.identifier, classes=e.classes, attributes={**e.attributes, "c": e.content[0].text[1:]}))

	# The command is executed first and then its contents are transformed. TODO: Is this what we want?
	if isinstance(e, Command):
		if not e.attributes["c"] in commands:
			raise NameError(f"Command not defined '{e.attributes['c']}'.")
		e = e.replaceSelf(executeCommand(commands[e.attributes["c"]], e))

	# Transformation of other elements. This is not done using a for cycle,
	# because deletions of elements would mess with it.
	children = ((child_name, getattr(e, child_name)) for child_name in e._children)
	for child_name, child in children:
		if hasattr(e, "content") and len(e.content) > 0:
			next = transform(e.content[0])
			while next != None:
				next = transform(next)
				print(next)

	# Return nearest sibling to transform
	return e.next



doc = convert_text(open(sys.argv[1], "r").read(), standalone=True, extra_args=["-f", "markdown+fenced_code_attributes"])

print(show(doc))
print(doc.content._children)
#transform(doc)
#print("---------------------")
#print(convert_text(doc, input_format="panflute", output_format="markdown"))