#!/usr/bin/env python3
# flake8: noqa

"""Build the docs with https://www.sphinx-doc.org."""

import functools
import pathlib
import sys
import webbrowser

from sphinx.cmd import build

SOURCE = pathlib.Path('docs')

TARGET = SOURCE / '_build'

RESULT = TARGET / 'index.html'

BROWSER_OPEN = '--open'

SKIP_OPEN_RESULT = '--no-open'

DEFAULT_ARGS = [BROWSER_OPEN, '-n', '-v', str(SOURCE), str(TARGET)]

OPEN_RESULT = BROWSER_OPEN in DEFAULT_ARGS

SELF = pathlib.Path(__file__)


print = functools.partial(print, sep='\n')


args = sys.argv[1:]
print(f'run {SELF.name} {args}')
if not args:
    args = DEFAULT_ARGS

if SKIP_OPEN_RESULT in args:
    open_result = None
    args = [a for a in args
            for name, value in [a.partition('=')[::2]]
            if name not in (SKIP_OPEN_RESULT, BROWSER_OPEN)]
elif any(a.partition('=')[0] == BROWSER_OPEN for a in args):
    open_result = RESULT

    values = {value for a in args
              for name, value in [a.partition('=')[::2]]
              if name == BROWSER_OPEN and value}
    if values:
        if len(values) != 1:
            raise ValueError(f'conflicting {BROWSER_OPEN}: {values}')
        value, = values
        if value:
            open_result = open_result.parent / value
    args = [a for a in args if a.partition('=')[0] != BROWSER_OPEN]

if not args:  # no pytest args given
    args = [a for a in DEFAULT_ARGS
            if a != SKIP_OPEN_RESULT and a.partition('=')[0] != BROWSER_OPEN]

if args == ['-b', 'doctest']:
    args += [str(SOURCE), str(SOURCE / '_doctest')]

print('', f'sphinx.cmd.build.main({args})',)
returncode = build.main(args)
print('', f'returncode: {returncode!r}', end='')

try:
    if 'doctest' not in args:
        print('', f'index: {RESULT}', f'assert {RESULT!r}.stat().st_size', end='')
        assert open_result.stat().st_size, f'non-empty {open_result}'
        if open_result:
            print('', f'webbrowser.open({open_result!r})', end='')
            webbrowser.open(open_result)
finally:
    sys.exit(returncode)

@@ -356,16 +356,22 @@
 ER_OPEN,
+ '-W',
  '-n', '
@@ -1510,16 +1510,22 @@
 rgs += %5B
+'-W', 
 str(SOUR

add -W for error on warning to build-docs.py