# registrar.py - utilities to register function for specific purpose

#

#  Copyright FUJIWARA Katsunori <foozy@lares.dti.ne.jp> and others

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from . import (

    configitems,

    error,

    pycompat,

    util,

)

# unlike the other registered items, config options are neither functions or

# classes. Registering the option is just small function call.

#

# We still add the official API to the registrar module for consistency with

# the other items extensions want might to register.

configitem = configitems.getitemregister

class _funcregistrarbase(object):

    """Base of decorator to register a function for specific purpose

    This decorator stores decorated functions into own dict 'table'.

    The least derived class can be defined by overriding 'formatdoc',

    for example::

        class keyword(_funcregistrarbase):

            _docformat = ":%s: %s"

    This should be used as below:

        keyword = registrar.keyword()

        @keyword('bar')

        def barfunc(*args, **kwargs):

            '''Explanation of bar keyword ....

            '''

            pass

    In this case:

    - 'barfunc' is stored as 'bar' in '_table' of an instance 'keyword' above

    - 'barfunc.__doc__' becomes ":bar: Explanation of bar keyword"

    """

    def __init__(self, table=None):

        if table is None:

            self._table = {}

        else:

            self._table = table

    def __call__(self, decl, *args, **kwargs):

        return lambda func: self._doregister(func, decl, *args, **kwargs)

    def _doregister(self, func, decl, *args, **kwargs):

        name = self._getname(decl)

        if name in self._table:

            msg = 'duplicate registration for name: "%s"' % name

            raise error.ProgrammingError(msg)

        if func.__doc__ and not util.safehasattr(func, '_origdoc'):

            doc = pycompat.sysbytes(func.__doc__).strip()

            func._origdoc = doc

            func.__doc__ = pycompat.sysstr(self._formatdoc(decl, doc))

        self._table[name] = func

        self._extrasetup(name, func, *args, **kwargs)

        return func

    def _parsefuncdecl(self, decl):

        """Parse function declaration and return the name of function in it

        """

        i = decl.find('(')

        if i >= 0:

            return decl[:i]

        else:

            return decl

    def _getname(self, decl):

        """Return the name of the registered function from decl

        Derived class should override this, if it allows more

        descriptive 'decl' string than just a name.

        """

        return decl

    _docformat = None

    def _formatdoc(self, decl, doc):

        """Return formatted document of the registered function for help

        'doc' is '__doc__.strip()' of the registered function.

        """

        return self._docformat % (decl, doc)

    def _extrasetup(self, name, func):

        """Execute exra setup for registered function, if needed

        """

class command(_funcregistrarbase):

    """Decorator to register a command function to table

    This class receives a command table as its argument. The table should

    be a dict.

    The created object can be used as a decorator for adding commands to

    that command table. This accepts multiple arguments to define a command.

    The first argument is the command name.

    The options argument is an iterable of tuples defining command arguments.

    See ``mercurial.fancyopts.fancyopts()`` for the format of each tuple.

    The synopsis argument defines a short, one line summary of how to use the

    command. This shows up in the help output.

    The norepo argument defines whether the command does not require a

    local repository. Most commands operate against a repository, thus the

    default is False.

    The optionalrepo argument defines whether the command optionally requires

    a local repository.

    The inferrepo argument defines whether to try to find a repository from the

    command line arguments. If True, arguments will be examined for potential

    repository locations. See ``findrepo()``. If a repository is found, it

    will be used.

    """

    def _doregister(self, func, name, options=(), synopsis=None,

        func.norepo = norepo

        func.optionalrepo = optionalrepo

        func.inferrepo = inferrepo

        if synopsis:

            self._table[name] = func, list(options), synopsis

        else:

            self._table[name] = func, list(options)

        return func

class revsetpredicate(_funcregistrarbase):

    """Decorator to register revset predicate

    Usage::

        revsetpredicate = registrar.revsetpredicate()

        @revsetpredicate('mypredicate(arg1, arg2[, arg3])')

        def mypredicatefunc(repo, subset, x):

            '''Explanation of this revset predicate ....

            '''

            pass

    The first string argument is used also in online help.

    Optional argument 'safe' indicates whether a predicate is safe for

    DoS attack (False by default).

    Optional argument 'takeorder' indicates whether a predicate function

    takes ordering policy as the last argument.

    Optional argument 'weight' indicates the estimated run-time cost, useful

    for static optimization, default is 1. Higher weight means more expensive.

    Usually, revsets that are fast and return only one revision has a weight of

    0.5 (ex. a symbol); revsets with O(changelog) complexity and read only the

    changelog have weight 10 (ex. author); revsets reading manifest deltas have

    weight 30 (ex. adds); revset reading manifest contents have weight 100

    (ex. contains). Note: those values are flexible. If the revset has a

    same big-O time complexity as 'contains', but with a smaller constant, it

    might have a weight of 90.

    'revsetpredicate' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'revsetpredicate' is used for

    decorating in extension.

    Otherwise, explicit 'revset.loadpredicate()' is needed.

    """

    _getname = _funcregistrarbase._parsefuncdecl

    _docformat = "``%s``\n    %s"

    def _extrasetup(self, name, func, safe=False, takeorder=False, weight=1):

        func._safe = safe

        func._takeorder = takeorder

        func._weight = weight

class filesetpredicate(_funcregistrarbase):

    """Decorator to register fileset predicate

    Usage::

        filesetpredicate = registrar.filesetpredicate()

        @filesetpredicate('mypredicate()')

        def mypredicatefunc(mctx, x):

            '''Explanation of this fileset predicate ....

            '''

            pass

    The first string argument is used also in online help.

    Optional argument 'callstatus' indicates whether a predicate

     implies 'matchctx.status()' at runtime or not (False, by

     default).

    Optional argument 'callexisting' indicates whether a predicate

    implies 'matchctx.existing()' at runtime or not (False, by

    default).

    'filesetpredicate' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'filesetpredicate' is used for

    decorating in extension.

    Otherwise, explicit 'fileset.loadpredicate()' is needed.

    """

    _getname = _funcregistrarbase._parsefuncdecl

    _docformat = "``%s``\n    %s"

    def _extrasetup(self, name, func, callstatus=False, callexisting=False):

        func._callstatus = callstatus

        func._callexisting = callexisting

class _templateregistrarbase(_funcregistrarbase):

    """Base of decorator to register functions as template specific one

    """

    _docformat = ":%s: %s"

class templatekeyword(_templateregistrarbase):

    """Decorator to register template keyword

    Usage::

        templatekeyword = registrar.templatekeyword()

        @templatekeyword('mykeyword')

        def mykeywordfunc(repo, ctx, templ, cache, revcache, **args):

            '''Explanation of this template keyword ....

            '''

            pass

    The first string argument is used also in online help.

    'templatekeyword' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'templatekeyword' is used for

    decorating in extension.

    Otherwise, explicit 'templatekw.loadkeyword()' is needed.

    """

class templatefilter(_templateregistrarbase):

    """Decorator to register template filer

    Usage::

        templatefilter = registrar.templatefilter()

        @templatefilter('myfilter')

        def myfilterfunc(text):

            '''Explanation of this template filter ....

            '''

            pass

    The first string argument is used also in online help.

    'templatefilter' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'templatefilter' is used for

    decorating in extension.

    Otherwise, explicit 'templatefilters.loadkeyword()' is needed.

    """

class templatefunc(_templateregistrarbase):

    """Decorator to register template function

    Usage::

        templatefunc = registrar.templatefunc()

        @templatefunc('myfunc(arg1, arg2[, arg3])', argspec='arg1 arg2 arg3')

        def myfuncfunc(context, mapping, args):

            '''Explanation of this template function ....

            '''

            pass

    The first string argument is used also in online help.

    If optional 'argspec' is defined, the function will receive 'args' as

    a dict of named arguments. Otherwise 'args' is a list of positional

    arguments.

    'templatefunc' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'templatefunc' is used for

    decorating in extension.

    Otherwise, explicit 'templater.loadfunction()' is needed.

    """

    _getname = _funcregistrarbase._parsefuncdecl

    def _extrasetup(self, name, func, argspec=None):

        func._argspec = argspec

class internalmerge(_funcregistrarbase):

    """Decorator to register in-process merge tool

    Usage::

        internalmerge = registrar.internalmerge()

        @internalmerge('mymerge', internalmerge.mergeonly,

                       onfailure=None, precheck=None):

        def mymergefunc(repo, mynode, orig, fcd, fco, fca,

                        toolconf, files, labels=None):

            '''Explanation of this internal merge tool ....

            '''

            return 1, False # means "conflicted", "no deletion needed"

    The first string argument is used to compose actual merge tool name,

    ":name" and "internal:name" (the latter is historical one).

    The second argument is one of merge types below:

    ========== ======== ======== =========

    merge type precheck premerge fullmerge

    ========== ======== ======== =========

    nomerge     x        x        x

    mergeonly   o        x        o

    fullmerge   o        o        o

    ========== ======== ======== =========

    Optional argument 'onfailure' is the format of warning message

    to be used at failure of merging (target filename is specified

    at formatting). Or, None or so, if warning message should be

    suppressed.

    Optional argument 'precheck' is the function to be used

    before actual invocation of internal merge tool itself.

    It takes as same arguments as internal merge tool does, other than

    'files' and 'labels'. If it returns false value, merging is aborted

    immediately (and file is marked as "unresolved").

    'internalmerge' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'internalmerge' is used for

    decorating in extension.

    Otherwise, explicit 'filemerge.loadinternalmerge()' is needed.

    """

    _docformat = "``:%s``\n    %s"

    # merge type definitions:

    nomerge = None

    mergeonly = 'mergeonly'  # just the full merge, no premerge

    fullmerge = 'fullmerge'  # both premerge and merge

    def _extrasetup(self, name, func, mergetype,

                    onfailure=None, precheck=None):

        func.mergetype = mergetype

        func.onfailure = onfailure

        func.precheck = precheck