Editorial Workflows

#coding: utf-8
import editor
import re

RGX_PFX = """
^([\t]*)			# In some cases some tab indents,
	(						# then possibly a prefix:
	[\-\*\+]\s| 	# unordered list item
  \d+\.\s|			# ordered list item,
  \#+\ *|				# hash header,
  \>+\s*|			# block quote, or
  \s{4}|					# literal code
  )
  (.*)$       # and perhaps some text ...
"""

def outdented_prefix(o_match):
	str_prefix = o_match.group(2)
	lng_prefix = len(str_prefix.rstrip())
	
	if len(str_prefix) > 0:
		str_first = str_prefix[0]
		
		if str_first in ['#', '>']:
			lng_new_level = lng_prefix - 1
			if lng_new_level < 1:
				return ''
			else:
				return ''.join([str_first * lng_new_level,' '])
		elif str_first == ' ':
			return str_prefix[4:]
		else:
			# bullets with zero or more tabs
			lng_tabs = len(o_match.group(1))
			if lng_tabs > 0: # tab(s) found
				return ''.join([(lng_tabs-1) * '\t', str_prefix])
			else:
				return ''
	else:
		return "# "

tpl_seln = editor.get_selection()

# FULLY SELECT FROM START TO END OF SELECTED LINE(S)
tpl_lines	 = editor.get_line_selection()
editor.set_selection(tpl_lines[0], tpl_lines[1])
str_text = editor.get_selected_text()

lst_lines = str_text.splitlines()
bln_single_line = (len(lst_lines) < 2)

# INDENT EACH LINE, ACCORDING TO ITS TYPE
rgx_pfx = re.compile(RGX_PFX, re.VERBOSE)
lst_new = []
for str_line in lst_lines:
	o_match = rgx_pfx.match(str_line)
	if o_match != None:
		lst_new += [outdented_prefix(o_match) + o_match.group(3)]
		

if lst_new != []:
	str_new = '\n'.join(lst_new) + '\n'
	lng_new = len(str_new)
	lng_delta = len(str_text) - lng_new
	editor.replace_text(tpl_lines[0], tpl_lines[1], str_new)
else:
	str_new = str_text
	lng_delta = 0
	
lng_new = len(str_new)
		
# AND RESTORE FULL LINE SELECTIONS, FOR FURTHER INDENT/OUTDENT
editor.set_selection(tpl_lines[0], tpl_lines[1])
tpl_lines = editor.get_line_selection()
lng_from = tpl_lines[0]
if bln_single_line:
	lng_start, lng_end = tpl_seln[0]-lng_delta, tpl_seln[1]-lng_delta
	if lng_start < lng_from:
		lng_start = lng_from
	if lng_end < lng_from:
		lng_end = lng_from
	
	editor.set_selection(lng_start, lng_end)
else:
	editor.set_selection(lng_from, lng_from + lng_new-1)