import sublime
import sublime_plugin
import re


class CycleCommentsCommand(sublime_plugin.TextCommand):

	def run(self, edit):

		view = self.view
		syntax_path = view.settings().get("syntax")

		if not syntax_path:
			return

		syntax_name = syntax_path.split("/")[-1] \
			.replace(".sublime-syntax", "") \
			.replace(".tmLanguage", "")

		settings = sublime.load_settings("commentcycle.sublime-settings")
		comment_styles = settings.get(syntax_name)

		if not comment_styles:
			sublime.status_message("No comment styles for {}".format(syntax_name))
			return

		# Match longest prefix first (## before #)
		comment_styles = sorted(comment_styles, key=lambda x: len(x[0]), reverse=True)

		for region in list(view.sel()):

			if region.empty():
				region = view.line(region)

			original = view.substr(region)

			indent_match = re.match(r'^(\s*)', original)
			indent = indent_match.group(1)
			content = original[len(indent):]

			stripped = content.strip()

			state = 0

			for i, pair in enumerate(comment_styles):

				start, end = pair

				if stripped.startswith(start):
					if not end or stripped.endswith(end):
						state = i + 1
						break

			next_state = (state + 1) % (len(comment_styles) + 1)

			# Remove current comment
			if state > 0:

				start, end = comment_styles[state - 1]

				stripped = stripped[len(start):].lstrip()

				if end:
					stripped = stripped[:-len(end)].rstrip()

			# Apply next comment
			if next_state > 0:

				start, end = comment_styles[next_state - 1]

				if end:
					stripped = "{} {} {}".format(start, stripped, end)
				else:
					stripped = "{} {}".format(start, stripped)

			new_line = indent + stripped

			view.replace(edit, region, new_line)