#hide
#default_exp export
#default_cls_lvl 3
from nbdev.showdoc import show_doc

#export
from nbdev.imports import *
from fastcore.script import *
from fastcore.foundation import *
from keyword import iskeyword
import nbformat

create_config("github", "nbdev", user='fastai', path='..', tst_flags='tst', cfg_name='test_settings.ini', recursive='False')
cfg = Config(cfg_name='test_settings.ini')
test_eq(cfg.lib_name, 'nbdev')
test_eq(cfg.git_url, "https://github.com/fastai/nbdev/tree/master/")
# test_eq(cfg.path("lib_path"), Path.cwd().parent/'nbdev')
# test_eq(cfg.path("nbs_path"), Path.cwd())
# test_eq(cfg.path("doc_path"), Path.cwd().parent/'docs')
test_eq(cfg.custom_sidebar, 'False')
test_eq(cfg.recursive, 'False')

#export
def read_nb(fname):
    "Read the notebook in `fname`."
    with open(Path(fname),'r', encoding='utf8') as f: return nbformat.reads(f.read(), as_version=4)

test_nb = read_nb('00_export.ipynb')

#export
def check_re(cell, pat, code_only=True):
    "Check if `cell` contains a line with regex `pat`"
    if code_only and cell['cell_type'] != 'code': return
    if isinstance(pat, str): pat = re.compile(pat, re.IGNORECASE | re.MULTILINE)
    cell_source = cell['source'].replace('\r', '') # Eliminate \r\n
    result = pat.search(cell_source)
    return result

cell = test_nb['cells'][1].copy()
assert check_re(cell, '#export') is not None
assert check_re(cell, re.compile('#export')) is not None
assert check_re(cell, '# bla') is None
cell['cell_type'] = 'markdown'
assert check_re(cell, '#export') is None
assert check_re(cell, '#export', code_only=False) is not None

#export
def check_re_multi(cell, pats, code_only=True):
    "Check if `cell` contains a line matching any regex in `pats`, returning the first match found"
    return L(pats).map_first(partial(check_re, cell, code_only=code_only))

cell = test_nb['cells'][0].copy()
cell['source'] = "a b c"
assert check_re(cell, 'a') is not None
assert check_re(cell, 'd') is None
# show that searching with patterns ['d','b','a'] will match 'b'
# i.e. 'd' is not found and we don't search for 'a'
assert check_re_multi(cell, ['d','b','a']).span() == (2,3)

#export
def _mk_flag_re(body, n_params, comment):
    "Compiles a regex for finding nbdev flags"
    assert body!=True, 'magics no longer supported'
    prefix = r"\s*\#\s*"
    param_group = ""
    if n_params == -1: param_group = r"[ \t]+(.+)"
    if n_params == 1: param_group = r"[ \t]+(\S+)"
    if n_params == (0,1): param_group = r"(?:[ \t]+(\S+))?"
    return re.compile(rf"""
# {comment}:
^            # beginning of line (since re.MULTILINE is passed)
{prefix}
{body}
{param_group}
[ \t]*       # any number of spaces and/or tabs
$            # end of line (since re.MULTILINE is passed)
""", re.MULTILINE | re.VERBOSE)

#hide
re_blank_test = _mk_flag_re('export[si]?', 0, "test")
re_mod_test = _mk_flag_re('export[si]?', 1, "test")
re_opt_test = _mk_flag_re('export[si]?', (0,1), "test")
for f in ['export', 'exports', 'exporti']:
    cell = nbformat.v4.new_code_cell(f'#{f}  \n some code')
    assert check_re(cell, re_blank_test) is not None
    assert check_re(cell, re_mod_test) is None
    assert check_re(cell, re_opt_test) is not None
    test_eq(check_re(cell, re_opt_test).groups()[0], None)
    cell.source = f'#{f} special.module \n some code'
    assert check_re(cell, re_blank_test) is None
    assert check_re(cell, re_mod_test) is not None
    test_eq(check_re(cell, re_mod_test).groups()[0], 'special.module')
    assert check_re(cell, re_opt_test) is not None
    test_eq(check_re(cell, re_opt_test).groups()[0], 'special.module')

#export
_re_blank_export = _mk_flag_re("export[si]?", 0,
    "Matches any line with #export, #exports or #exporti without any module name")

#export
_re_mod_export = _mk_flag_re("export[si]?", 1,
    "Matches any line with #export, #exports or #exporti with a module name and catches it in group 1")

#export
_re_internal_export = _mk_flag_re("exporti", (0,1),
    "Matches any line with #exporti with or without a module name")

#exporti
def _is_external_export(tst):
    "Check if a cell is an external or internal export. `tst` is an re match"
    return _re_internal_export.search(tst.string) is None

#export
def is_export(cell, default):
    "Check if `cell` is to be exported and returns the name of the module to export it if provided"
    tst = check_re(cell, _re_blank_export)
    if tst:
        if default is None:
            print(f"No export destination, ignored:\n{cell['source']}")
        return default, _is_external_export(tst)
    tst = check_re(cell, _re_mod_export)
    if tst: return os.path.sep.join(tst.groups()[0].split('.')), _is_external_export(tst)
    else: return None

cell = test_nb['cells'][1].copy()
test_eq(is_export(cell, 'export'), ('export', True))
cell['source'] = "# exports"
test_eq(is_export(cell, 'export'), ('export', True))
cell['source'] = "# exporti"
test_eq(is_export(cell, 'export'), ('export', False))
cell['source'] = "# export mod"
test_eq(is_export(cell, 'export'), ('mod', True))

#hide
cell['source'] = "# export mod.file"
test_eq(is_export(cell, 'export'), (f'mod{os.path.sep}file', True))
cell['source'] = "# exporti mod.file"
test_eq(is_export(cell, 'export'), (f'mod{os.path.sep}file', False))
cell['source'] = "# expt mod.file"
assert is_export(cell, 'export') is None
cell['source'] = "# exportmod.file"
assert is_export(cell, 'export') is None
cell['source'] = "# exportsmod.file"
assert is_export(cell, 'export') is None
cell['source'] = "# exporti mod file"
assert is_export(cell, 'export') is None

#export
_re_default_exp = _mk_flag_re('default_exp', 1, "Matches any line with #default_exp with a module name")

#export
def find_default_export(cells):
    "Find in `cells` the default export module."
    res = L(cells).map_first(check_re, pat=_re_default_exp)
    return res.groups()[0] if res else None

test_eq(find_default_export(test_nb['cells']), 'export')
assert find_default_export(test_nb['cells'][2:]) is None

#hide
mods = [f'mod{i}' for i in range(3)]
cells = [{'cell_type': 'code', 'source': f'#default_exp {mod}'} for mod in mods]
for i, mod in enumerate(mods): test_eq(mod, find_default_export(cells[i:]))

#export
_re_patch_func = re.compile(r"""
# Catches any function decorated with @patch, its name in group 1 and the patched class in group 2
@patch         # At any place in the cell, something that begins with @patch
(?:\s*@.*)*    # Any other decorator applied to the function
\s*def         # Any number of whitespace (including a new line probably) followed by def
\s+            # One whitespace or more
([^\(\s]+)     # Catch a group composed of anything but whitespace or an opening parenthesis (name of the function)
\s*\(          # Any number of whitespace followed by an opening parenthesis
[^:]*          # Any number of character different of : (the name of the first arg that is type-annotated)
:\s*           # A column followed by any number of whitespace
(?:            # Non-catching group with either
([^,\s\(\)]*)  #    a group composed of anything but a comma, a parenthesis or whitespace (name of the class)
|              #  or
(\([^\)]*\)))  #    a group composed of something between parenthesis (tuple of classes)
\s*            # Any number of whitespace
(?:,|\))       # Non-catching group with either a comma or a closing parenthesis
""", re.VERBOSE)

#hide
tst = _re_patch_func.search("""
@patch
def func(obj:Class):""")
test_eq(tst.groups(), ("func", "Class", None))
tst = _re_patch_func.search("""
@patch
def func (obj:Class, a)""")
test_eq(tst.groups(), ("func", "Class", None))
tst = _re_patch_func.search("""
@patch
def func (obj:(Class1, Class2), a)""")
test_eq(tst.groups(), ("func", None, "(Class1, Class2)"))
tst = _re_patch_func.search("""
@patch
def func (obj:(Class1, Class2), a:int)->int:""")
test_eq(tst.groups(), ("func", None, "(Class1, Class2)"))
tst = _re_patch_func.search("""
@patch
@log_args(but='a,b')
@funcs_kwargs
def func (obj:(Class1, Class2), a:int)->int:""")
test_eq(tst.groups(), ("func", None, "(Class1, Class2)"))
tst = _re_patch_func.search("""
@patch
@contextmanager
def func (obj:Class, a:int)->int:""")
test_eq(tst.groups(), ("func", "Class", None))

#export
_re_typedispatch_func = re.compile(r"""
# Catches any function decorated with @typedispatch
(@typedispatch  # At any place in the cell, catch a group with something that begins with @typedispatch
\s*def          # Any number of whitespace (including a new line probably) followed by def
\s+             # One whitespace or more
[^\(]+          # Anything but whitespace or an opening parenthesis (name of the function)
\s*\(           # Any number of whitespace followed by an opening parenthesis
[^\)]*          # Any number of character different of )
\)[\s\S]*:)     # A closing parenthesis followed by any number of characters and whitespace (type annotation) and :
""", re.VERBOSE)

#hide
assert _re_typedispatch_func.search("@typedispatch\ndef func(a, b):").groups() == ('@typedispatch\ndef func(a, b):',)
assert (_re_typedispatch_func.search("@typedispatch\ndef func(a:str, b:bool)->int:").groups() ==
                                    ('@typedispatch\ndef func(a:str, b:bool)->int:',))

#export
_re_class_func_def = re.compile(r"""
# Catches any 0-indented function or class definition with its name in group 1
^              # Beginning of a line (since re.MULTILINE is passed)
(?:async\sdef|def|class)  # Non-catching group for def or class
\s+            # One whitespace or more
([^\(\s]+)     # Catching group with any character except an opening parenthesis or a whitespace (name)
\s*            # Any number of whitespace
(?:\(|:)       # Non-catching group with either an opening parenthesis or a : (classes don't need ())
""", re.MULTILINE | re.VERBOSE)

#hide
test_eq(_re_class_func_def.search("class Class:").groups(), ('Class',))
test_eq(_re_class_func_def.search("def func(a, b):").groups(), ('func',))
test_eq(_re_class_func_def.search("def func(a:str, b:bool)->int:").groups(), ('func',))
test_eq(_re_class_func_def.search("async def func(a, b):").groups(), ('func',))

#export
_re_obj_def = re.compile(r"""
# Catches any 0-indented object definition (bla = thing) with its name in group 1
^                          # Beginning of a line (since re.MULTILINE is passed)
([_a-zA-Z]+[a-zA-Z0-9_\.]*)  # Catch a group which is a valid python variable name
\s*                        # Any number of whitespace
(?::\s*\S.*|)=  # Non-catching group of either a colon followed by a type annotation, or nothing; followed by an =
""", re.MULTILINE | re.VERBOSE)

#hide
test_eq(_re_obj_def.search("a = 1").groups(), ('a',))
test_eq(_re_obj_def.search("a.b = 1").groups(), ('a.b',))
test_eq(_re_obj_def.search("_aA1=1").groups(), ('_aA1',))
test_eq(_re_obj_def.search("a : int =1").groups(), ('a',))
test_eq(_re_obj_def.search("a:f(':=')=1").groups(), ('a',))
assert _re_obj_def.search("@abc=2") is None
assert _re_obj_def.search("a a=2") is None

#export
def _not_private(n):
    for t in n.split('.'):
        if (t.startswith('_') and not t.startswith('__')) or t.startswith('@'): return False
    return '\\' not in t and '^' not in t and '[' not in t and t != 'else'

def export_names(code, func_only=False):
    "Find the names of the objects, functions or classes defined in `code` that are exported."
    #Format monkey-patches with @patch
    def _f(gps):
        nm, cls, t = gps.groups()
        if cls is not None: return f"def {cls}.{nm}():"
        return '\n'.join([f"def {c}.{nm}():" for c in re.split(', *', t[1:-1])])

    code = _re_typedispatch_func.sub('', code)
    code = _re_patch_func.sub(_f, code)
    names = _re_class_func_def.findall(code)
    if not func_only: names += _re_obj_def.findall(code)
    return [n for n in names if _not_private(n) and not iskeyword(n)]

test_eq(export_names("def my_func(x):\n  pass\nclass MyClass():"), ["my_func", "MyClass"])

#hide
#Indented funcs are ignored (funcs inside a class)
test_eq(export_names("  def my_func(x):\n  pass\nclass MyClass():"), ["MyClass"])

#Private funcs are ignored, dunder are not
test_eq(export_names("def _my_func():\n  pass\nclass MyClass():"), ["MyClass"])
test_eq(export_names("__version__ = 1:\n  pass\nclass MyClass():"), ["MyClass", "__version__"])

#trailing spaces
test_eq(export_names("def my_func ():\n  pass\nclass MyClass():"), ["my_func", "MyClass"])

#class without parenthesis
test_eq(export_names("def my_func ():\n  pass\nclass MyClass:"), ["my_func", "MyClass"])

#object and funcs
test_eq(export_names("def my_func ():\n  pass\ndefault_bla=[]:"), ["my_func", "default_bla"])
test_eq(export_names("def my_func ():\n  pass\ndefault_bla=[]:", func_only=True), ["my_func"])

#Private objects are ignored
test_eq(export_names("def my_func ():\n  pass\n_default_bla = []:"), ["my_func"])

#Objects with dots are privates if one part is private
test_eq(export_names("def my_func ():\n  pass\ndefault.bla = []:"), ["my_func", "default.bla"])
test_eq(export_names("def my_func ():\n  pass\ndefault._bla = []:"), ["my_func"])

#Monkey-path with @patch are properly renamed
test_eq(export_names("@patch\ndef my_func(x:Class):\n  pass"), ["Class.my_func"])
test_eq(export_names("@patch\ndef my_func(x:Class):\n  pass", func_only=True), ["Class.my_func"])
test_eq(export_names("some code\n@patch\ndef my_func(x:Class, y):\n  pass"), ["Class.my_func"])
test_eq(export_names("some code\n@patch\ndef my_func(x:(Class1,Class2), y):\n  pass"), ["Class1.my_func", "Class2.my_func"])

#Check delegates
test_eq(export_names("@delegates(keep=True)\nclass someClass:\n  pass"), ["someClass"])

#Typedispatch decorated functions shouldn't be added
test_eq(export_names("@patch\ndef my_func(x:Class):\n  pass\n@typedispatch\ndef func(x: TensorImage): pass"), ["Class.my_func"])

#try, except and other keywords should not be picked up (these can look like object def with type annotation)
test_eq(export_names("try:\n    a=1\nexcept:\n    b=2"), [])
test_eq(export_names("try:\n    this_might_work\nexcept:\n    b=2"), [])

#export
_re_all_def   = re.compile(r"""
# Catches a cell with defines \_all\_ = [\*\*] and get that \*\* in group 1
^_all_   #  Beginning of line (since re.MULTILINE is passed)
\s*=\s*  #  Any number of whitespace, =, any number of whitespace
\[       #  Opening [
([^\n\]]*) #  Catching group with anything except a ] or newline
\]       #  Closing ]
""", re.MULTILINE | re.VERBOSE)

#Same with __all__
_re__all__def = re.compile(r'^__all__\s*=\s*\[([^\]]*)\]', re.MULTILINE)

#export
def extra_add(flags, code):
    "Catch adds to `__all__` required by a cell with `_all_=`"
    m = check_re({'source': code}, _re_all_def, False)
    if m:
        code = m.re.sub('#nbdev_' + 'comment \g<0>', code)
        code = re.sub(r'([^\n]|^)\n*$', r'\1', code)
    if not m: return [], code
    def clean_quotes(s):
        "Return `s` enclosed in single quotes, removing double quotes if needed"
        if s.startswith("'") and s.endswith("'"): return s
        if s.startswith('"') and s.endswith('"'): s = s[1:-1]
        return f"'{s}'"
    return [clean_quotes(s) for s in parse_line(m.group(1))], code

#hide
for code, expected in [
        ['_all_ = ["func", "func1", "func2"]', 
         (["'func'", "'func1'", "'func2'"],'#nbdev_comment _all_ = ["func", "func1", "func2"]')],
        ['_all_=[func, func1, func2]', 
         (["'func'", "'func1'", "'func2'"],'#nbdev_comment _all_=[func, func1, func2]')],
        ["_all_ = ['func', 'func1', 'func2']", 
         (["'func'", "'func1'", "'func2'"],"#nbdev_comment _all_ = ['func', 'func1', 'func2']")],
        ['_all_ = ["func",   "func1" , "func2"]', 
         (["'func'", "'func1'", "'func2'"],'#nbdev_comment _all_ = ["func",   "func1" , "func2"]')],
        ["_all_ = ['func','func1', 'func2']\n", 
         (["'func'", "'func1'", "'func2'"],"#nbdev_comment _all_ = ['func','func1', 'func2']")],
        ["_all_ = ['func']\n_all_ = ['func1', 'func2']\n", 
         (["'func'"],"#nbdev_comment _all_ = ['func']\n#nbdev_comment _all_ = ['func1', 'func2']")],
        ['code\n\n_all_ = ["func", "func1", "func2"]', 
         (["'func'", "'func1'", "'func2'"],'code\n\n#nbdev_comment _all_ = ["func", "func1", "func2"]')],
        ['code\n\n_all_ = [func]\nmore code', 
         (["'func'"],'code\n\n#nbdev_comment _all_ = [func]\nmore code')]]:
    test_eq(extra_add('', code), expected)
    
# line breaks within the list of names means _all_ is ignored
test_eq(extra_add('', "_all_ = ['func',\n'func1', 'func2']\n"), ([],"_all_ = ['func',\n'func1', 'func2']\n"))

#export
_re_from_future_import = re.compile(r"^from[ \t]+__future__[ \t]+import.*$", re.MULTILINE)

def _from_future_import(fname, flags, code, to_dict=None):
    "Write `__future__` imports to `fname` and return `code` with `__future__` imports commented out"
    from_future_imports = _re_from_future_import.findall(code)
    if from_future_imports: code = _re_from_future_import.sub('#nbdev' + '_comment \g<0>', code)
    else: from_future_imports = _re_from_future_import.findall(flags)
    if not from_future_imports or to_dict is not None: return code
    with open(fname, 'r', encoding='utf8') as f: text = f.read()
    start = _re__all__def.search(text).start()
    with open(fname, 'w', encoding='utf8') as f:
        f.write('\n'.join([text[:start], *from_future_imports, '\n', text[start:]]))
    return code

#hide
txt = """
# AUTOHEADER ... File to edit: mod.ipynb (unless otherwise specified).

__all__ = [my_file, MyClas]
# Cell
def valid_code(): pass"""
expected_txt = """
# AUTOHEADER ... File to edit: mod.ipynb (unless otherwise specified).


from  __future__ import  annotations    
from __future__ import generator_stop


__all__ = [my_file, MyClas]
# Cell
def valid_code(): pass"""
flags="# export"
code = """
# comment
from  __future__ import  annotations    
valid_code = False # but _from_future_import will work anyway
from __future__ import generator_stop
 from __future__ import not_zero_indented
valid_code = True
"""
expected_code = """
# comment
#nbdev_comment from  __future__ import  annotations    
valid_code = False # but _from_future_import will work anyway
#nbdev_comment from __future__ import generator_stop
 from __future__ import not_zero_indented
valid_code = True
"""

def _run_from_future_import_test():
    fname = 'test_from_future_import.txt'
    with open(fname, 'w', encoding='utf8') as f: f.write(txt)

    actual_code=_from_future_import(fname, flags, code, {})
    test_eq(expected_code, actual_code)
    with open(fname, 'r', encoding='utf8') as f: test_eq(f.read(), txt)

    actual_code=_from_future_import(fname, flags, code)
    test_eq(expected_code, actual_code)
    with open(fname, 'r', encoding='utf8') as f: test_eq(f.read(), expected_txt)

    os.remove(fname)

_run_from_future_import_test()

flags="""from  __future__ import  annotations    
from __future__ import generator_stop
#export"""
code = ""
expected_code = ""
fname = 'test_from_future_import.txt'

_run_from_future_import_test()

#export
def _add2all(fname, names, line_width=120):
    if len(names) == 0: return
    with open(fname, 'r', encoding='utf8') as f: text = f.read()
    tw = TextWrapper(width=120, initial_indent='', subsequent_indent=' '*11, break_long_words=False)
    re_all = _re__all__def.search(text)
    start,end = re_all.start(),re_all.end()
    text_all = tw.wrap(f"{text[start:end-1]}{'' if text[end-2]=='[' else ', '}{', '.join(names)}]")
    with open(fname, 'w', encoding='utf8') as f: f.write(text[:start] + '\n'.join(text_all) + text[end:])

#hide
fname = 'test_add.txt'
with open(fname, 'w', encoding='utf8') as f: f.write("Bla\n__all__ = [my_file, MyClas]\nBli")
_add2all(fname, ['new_function'])
with open(fname, 'r', encoding='utf8') as f: 
    test_eq(f.read(), "Bla\n__all__ = [my_file, MyClas, new_function]\nBli")
_add2all(fname, [f'new_function{i}' for i in range(10)])
with open(fname, 'r', encoding='utf8') as f: 
    test_eq(f.read(), """Bla
__all__ = [my_file, MyClas, new_function, new_function0, new_function1, new_function2, new_function3, new_function4,
           new_function5, new_function6, new_function7, new_function8, new_function9]
Bli""")
os.remove(fname)

#export
def relative_import(name, fname):
    "Convert a module `name` to a name relative to `fname`"
    mods = name.split('.')
    splits = str(fname).split(os.path.sep)
    if mods[0] not in splits: return name
    i=len(splits)-1
    while i>0 and splits[i] != mods[0]: i-=1
    splits = splits[i:]
    while len(mods)>0 and splits[0] == mods[0]: splits,mods = splits[1:],mods[1:]
    return '.' * (len(splits)) + '.'.join(mods)

test_eq(relative_import('nbdev.core', Path.cwd()/'nbdev'/'data.py'), '.core')
test_eq(relative_import('nbdev.core', Path('nbdev')/'vision'/'data.py'), '..core')
test_eq(relative_import('nbdev.vision.transform', Path('nbdev')/'vision'/'data.py'), '.transform')
test_eq(relative_import('nbdev.notebook.core', Path('nbdev')/'data'/'external.py'), '..notebook.core')
test_eq(relative_import('nbdev.vision', Path('nbdev')/'vision'/'learner.py'), '.')

#export
_re_import = ReLibName(r'^(\s*)from (LIB_NAME\.\S*) import (.*)$')

#export
def _deal_import(code_lines, fname):
    def _replace(m):
        sp,mod,obj = m.groups()
        return f"{sp}from {relative_import(mod, fname)} import {obj}"
    return [_re_import.re.sub(_replace,line) for line in code_lines]

#hide
lines = ["from nbdev.core import *", 
         "nothing to see", 
         "  from nbdev.vision import bla1, bla2", 
         "from nbdev.vision import models",
         "import nbdev.vision"]
test_eq(_deal_import(lines, Path.cwd()/'nbdev'/'data.py'), [
    "from .core import *", 
    "nothing to see", 
    "  from .vision import bla1, bla2", 
    "from .vision import models",
    "import nbdev.vision"
])

#export
_re_index_custom = re.compile(r'def custom_doc_links\(name\):(.*)$', re.DOTALL)

#export
def reset_nbdev_module():
    "Create a skeleton for <code>_nbdev</code>"
    fname = Config().path("lib_path")/'_nbdev.py'
    fname.parent.mkdir(parents=True, exist_ok=True)
    sep = '\n'* (int(Config().get('cell_spacing', '1'))+1)
    if fname.is_file():
        with open(fname, 'r') as f: search = _re_index_custom.search(f.read())
    else: search = None
    prev_code = search.groups()[0] if search is not None else ' return None\n'
    with open(fname, 'w') as f:
        f.write(f"# AUTOGENERATED BY NBDEV! DO NOT EDIT!")
        f.write('\n\n__all__ = ["index", "modules", "custom_doc_links", "git_url"]')
        f.write('\n\nindex = {}')
        f.write('\n\nmodules = []')
        f.write(f'\n\ndoc_url = "{Config().doc_host}{Config().doc_baseurl}"')
        f.write(f'\n\ngit_url = "{Config().git_url}"')
        f.write(f'{sep}def custom_doc_links(name):{prev_code}')

#export
class _EmptyModule():
    def __init__(self):
        self.index,self.modules = {},[]
        self.doc_url,self.git_url = f"{Config().doc_host}{Config().doc_baseurl}",Config().git_url

    def custom_doc_links(self, name): return None

#export
def get_nbdev_module():
    "Reads <code>_nbdev</code>"
    try:
        spec = importlib.util.spec_from_file_location(f"{Config().lib_name}._nbdev", Config().path("lib_path")/'_nbdev.py')
        mod = importlib.util.module_from_spec(spec)
        spec.loader.exec_module(mod)
        return mod
    except: return _EmptyModule()

#export
_re_index_idx = re.compile(r'index\s*=\s*{[^}]*}')
_re_index_mod = re.compile(r'modules\s*=\s*\[[^\]]*\]')

#export
def save_nbdev_module(mod):
    "Save `mod` inside <code>_nbdev</code>"
    fname = Config().path("lib_path")/'_nbdev.py'
    with open(fname, 'r') as f: code = f.read()
    t = r',\n         '.join([f'"{k}": "{v}"' for k,v in mod.index.items()])
    code = _re_index_idx.sub("index = {"+ t +"}", code)
    t = r',\n           '.join(['"' + f.replace('\\','/') + '"' for f in mod.modules])
    code = _re_index_mod.sub(f"modules = [{t}]", code)
    with open(fname, 'w') as f: f.write(code)

#hide
ind,ind_bak = Config().path("lib_path")/'_nbdev.py',Config().path("lib_path")/'_nbdev.bak'
if ind.exists(): shutil.move(ind, ind_bak)
try:
    reset_nbdev_module()
    mod = get_nbdev_module()
    test_eq(mod.index, {})
    test_eq(mod.modules, [])

    mod.index = {'foo':'bar'}
    mod.modules.append('lala.bla')
    save_nbdev_module(mod)

    mod = get_nbdev_module()
    test_eq(mod.index, {'foo':'bar'})
    test_eq(mod.modules, ['lala.bla'])
finally:
    if ind_bak.exists(): shutil.move(ind_bak, ind)

#export
def split_flags_and_code(cell, return_type=list):
    "Splits the `source` of a cell into 2 parts and returns (flags, code)"
    source_str = cell['source'].replace('\r', '')
    code_lines = source_str.split('\n')
    split_pos = 0 if code_lines[0].strip().startswith('#') else -1
    for i, line in enumerate(code_lines):
        if not line.startswith('#') and line.strip() and not _re_from_future_import.match(line): break
    split_pos+=1
    res = code_lines[:split_pos], code_lines[split_pos:]
    if return_type is list: return res
    return tuple('\n'.join(r) for r in res)

def _test_split_flags_and_code(expected_flags, expected_code):
    cell = nbformat.v4.new_code_cell('\n'.join(expected_flags + expected_code))
    test_eq((expected_flags, expected_code), split_flags_and_code(cell))
    expected=('\n'.join(expected_flags), '\n'.join(expected_code))
    test_eq(expected, split_flags_and_code(cell, str))
    
_test_split_flags_and_code([
    '#export'],
    ['# TODO: write this function',
    'def func(x): pass'])

#export
def create_mod_file(fname, nb_path, bare=False):
    "Create a module file for `fname`."
    bare = str(Config().get('bare', bare)) == 'True'
    fname.parent.mkdir(parents=True, exist_ok=True)
    file_path = os.path.relpath(nb_path, Config().config_file.parent).replace('\\', '/')
    with open(fname, 'w') as f:
        if not bare: f.write(f"# AUTOGENERATED! DO NOT EDIT! File to edit: {file_path} (unless otherwise specified).")
        f.write('\n\n__all__ = []')

#export
def create_mod_files(files, to_dict=False, bare=False):
    "Create mod files for default exports found in `files`"
    modules = []
    for f in sorted(files):
        fname = Path(f)
        nb = read_nb(fname)
        default = find_default_export(nb['cells'])
        if default is not None:
            default = os.path.sep.join(default.split('.'))
            modules.append(default)
            if not to_dict:
                create_mod_file(Config().path("lib_path")/f'{default}.py', Config().path("nbs_path")/f'{fname}', bare=bare)
    return modules

#export
def _notebook2script(fname, modules, silent=False, to_dict=None, bare=False):
    "Finds cells starting with `#export` and puts them into a module created by `create_mod_files`"
    bare = str(Config().get('bare', bare)) == 'True'
    if os.environ.get('IN_TEST',0): return  # don't export if running tests
    sep = '\n'* (int(Config().get('cell_spacing', '1'))+1)
    fname = Path(fname)
    nb = read_nb(fname)
    default = find_default_export(nb['cells'])
    if default is not None:
        default = os.path.sep.join(default.split('.'))
    mod = get_nbdev_module()
    exports = [is_export(c, default) for c in nb['cells']]
    cells = [(i,c,e) for i,(c,e) in enumerate(zip(nb['cells'],exports)) if e is not None]
    for i,c,(e,a) in cells:
        if e not in modules: print(f'Warning: Exporting to "{e}.py" but this module is not part of this build')
        fname_out = Config().path("lib_path")/f'{e}.py'
        if bare: orig = "\n"
        else: orig = (f'# {"" if a else "Internal "}C' if e==default else f'# Comes from {fname.name}, c') + 'ell\n'
        flag_lines,code_lines = split_flags_and_code(c)
        code_lines = _deal_import(code_lines, fname_out)
        code = sep + orig + '\n'.join(code_lines)
        names = export_names(code)
        flags = '\n'.join(flag_lines)
        extra,code = extra_add(flags, code)
        code = _from_future_import(fname_out, flags, code, to_dict)
        if a:
            if to_dict is None: _add2all(fname_out, [f"'{f}'" for f in names if '.' not in f and len(f) > 0] + extra)
        mod.index.update({f: fname.name for f in names})
        code = re.sub(r' +$', '', code, flags=re.MULTILINE)
        if code != sep + orig[:-1]:
            if to_dict is not None: to_dict[e].append((i, fname, code))
            else:
                with open(fname_out, 'a', encoding='utf8') as f: f.write(code)
        if f'{e}.py' not in mod.modules: mod.modules.append(f'{e}.py')
    save_nbdev_module(mod)

    if not silent: print(f"Converted {fname.name}.")
    return to_dict

#hide
with open(Config().path("lib_path")/('export.py')) as f: l = f.readline()
test_eq(l, '# AUTOGENERATED! DO NOT EDIT! File to edit: nbs/00_export.ipynb (unless otherwise specified).\n')

#export
def add_init(path):
    "Add `__init__.py` in all subdirs of `path` containing python files if it's not there already"
    for p,d,f in os.walk(path):
        for f_ in f:
            if f_.endswith('.py'):
                if not (Path(p)/'__init__.py').exists(): (Path(p)/'__init__.py').touch()
                break

with tempfile.TemporaryDirectory() as d:
    os.makedirs(Path(d)/'a', exist_ok=True)
    (Path(d)/'a'/'f.py').touch()
    os.makedirs(Path(d)/'a/b', exist_ok=True)
    (Path(d)/'a'/'b'/'f.py').touch()
    add_init(d)
    assert not (Path(d)/'__init__.py').exists()
    for e in [Path(d)/'a', Path(d)/'a/b']:
        assert (e/'__init__.py').exists()

#export
_re_version = re.compile('^__version__\s*=.*$', re.MULTILINE)

#export
def update_version():
    "Add or update `__version__` in the main `__init__.py` of the library"
    fname = Config().path("lib_path")/'__init__.py'
    if not fname.exists(): fname.touch()
    version = f'__version__ = "{Config().version}"'
    with open(fname, 'r') as f: code = f.read()
    if _re_version.search(code) is None: code = version + "\n" + code
    else: code = _re_version.sub(version, code)
    with open(fname, 'w') as f: f.write(code)

#export
_re_baseurl = re.compile('^baseurl\s*:.*$', re.MULTILINE)

#export
def update_baseurl():
    "Add or update `baseurl` in `_config.yml` for the docs"
    fname = Config().path("doc_path")/'_config.yml'
    if not fname.exists(): return
    with open(fname, 'r') as f: code = f.read()
    if _re_baseurl.search(code) is None: code = code + f"\nbaseurl: {Config().doc_baseurl}"
    else: code = _re_baseurl.sub(f"baseurl: {Config().doc_baseurl}", code)
    with open(fname, 'w') as f: f.write(code)

#export
def nbglob(fname=None, recursive=None, extension='.ipynb', config_key='nbs_path') -> L:
    "Find all files in a directory matching an extension given a `config_key`. Ignores hidden directories and filenames starting with `_`.  If argument `recursive` is not set to `True` or `False`, this value is retreived from settings.ini with a default of `False`."
    if recursive == None: recursive=Config().get('recursive', 'False').lower() == 'true'
    fname = Config().path(config_key) if fname is None else Path(fname)
    if fname.is_dir(): fname = f'{fname.absolute()}/**/*{extension}' if recursive else f'{fname.absolute()}/*{extension}'
    fls = L(glob.glob(str(fname), recursive=recursive)).filter(lambda x: '/.' not in x).map(Path)
    return fls.filter(lambda x: not x.name.startswith('_') and x.name.endswith(extension))

#hide
with tempfile.TemporaryDirectory() as d:
    os.makedirs(Path(d)/'a', exist_ok=True)
    (Path(d)/'a'/'a.ipynb').touch()
    (Path(d)/'a'/'fake_a.ipynb').touch()
    os.makedirs(Path(d)/'a/b', exist_ok=True)
    (Path(d)/'a'/'b'/'fake_b.ipynb').touch()
    os.makedirs(Path(d)/'a/b/c', exist_ok=True)
    (Path(d)/'a'/'b'/'c'/'fake_c.ipynb').touch()
    (Path(d)/'a'/'b'/'c'/'foo_c.ipynb').touch()
    
    if sys.platform != "win32":
        assert len(nbglob(str(Path(f'{str(d)}/**/foo*')), recursive=True)) == 1
    assert len(nbglob(d, recursive=True)) == 5
    assert len(nbglob(d, recursive=False)) == 0
    assert len(nbglob(str(Path(f'{d}/a')), recursive=False)) == 2

#hide
if sys.platform != "win32":
    assert len(nbglob('*')) > 1
    assert len(nbglob('*')) >  len(nbglob('0*'))

assert not nbglob().filter(lambda x: '.ipynb_checkpoints' in str(x))

#hide
fnames = nbglob()
test_eq(len(fnames) > 0, True)

fnames = nbglob(fnames[0])
test_eq(len(fnames), 1)

#hide
fnames = nbglob(extension='.py', config_key='lib_path')
test_eq(len(fnames) > 1, True)

#export
def notebook2script(fname=None, silent=False, to_dict=False, bare=False):
    "Convert notebooks matching `fname` to modules"
    # initial checks
    if os.environ.get('IN_TEST',0): return  # don't export if running tests
    if fname is None:
        reset_nbdev_module()
        update_version()
        update_baseurl()
    files = nbglob(fname=fname)
    d = collections.defaultdict(list) if to_dict else None
    modules = create_mod_files(files, to_dict, bare=bare)
    for f in sorted(files): d = _notebook2script(f, modules, silent=silent, to_dict=d, bare=bare)
    if to_dict: return d
    else: add_init(Config().path("lib_path"))

#export
class DocsTestClass:
    "for tests only"
    def test(): pass

#hide
#exporti
#for tests only
def update_lib_with_exporti_testfn(): pass