# Copyright 2013-2021 The Meson development team

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from .base import Dependency, ExternalDependency, DependencyException, DependencyMethods, NotFoundDependency
from .cmake import CMakeDependency
from .dub import DubDependency
from .framework import ExtraFrameworkDependency
from .pkgconfig import PkgConfigDependency

from ..mesonlib import listify, MachineChoice, PerMachine
from .. import mlog
import functools
import typing as T

if T.TYPE_CHECKING:
    from ..environment import Environment
    from .factory import DependencyFactory, WrappedFactoryFunc, DependencyGenerator

# These must be defined in this file to avoid cyclical references.
packages: T.Dict[
    str,
    T.Union[T.Type[ExternalDependency], 'DependencyFactory', 'WrappedFactoryFunc']
] = {}
_packages_accept_language: T.Set[str] = set()

if T.TYPE_CHECKING:
    TV_DepIDEntry = T.Union[str, bool, int, T.Tuple[str, ...]]
    TV_DepID = T.Tuple[T.Tuple[str, TV_DepIDEntry], ...]


def get_dep_identifier(name: str, kwargs: T.Dict[str, T.Any]) -> 'TV_DepID':
    identifier: 'TV_DepID' = (('name', name), )
    from ..interpreter import permitted_dependency_kwargs
    assert len(permitted_dependency_kwargs) == 19, \
           'Extra kwargs have been added to dependency(), please review if it makes sense to handle it here'
    for key, value in kwargs.items():
        # 'version' is irrelevant for caching; the caller must check version matches
        # 'native' is handled above with `for_machine`
        # 'required' is irrelevant for caching; the caller handles it separately
        # 'fallback' and 'allow_fallback' is not part of the cache because,
        #     once a dependency has been found through a fallback, it should
        #     be used for the rest of the Meson run.
        # 'default_options' is only used in fallback case
        # 'not_found_message' has no impact on the dependency lookup
        # 'include_type' is handled after the dependency lookup
        if key in ('version', 'native', 'required', 'fallback', 'allow_fallback', 'default_options',
                   'not_found_message', 'include_type'):
            continue
        # All keyword arguments are strings, ints, or lists (or lists of lists)
        if isinstance(value, list):
            value = frozenset(listify(value))
            for i in value:
                assert isinstance(i, str)
        else:
            assert isinstance(value, (str, bool, int))
        identifier += (key, value)
    return identifier

display_name_map = {
    'boost': 'Boost',
    'cuda': 'CUDA',
    'dub': 'DUB',
    'gmock': 'GMock',
    'gtest': 'GTest',
    'hdf5': 'HDF5',
    'llvm': 'LLVM',
    'mpi': 'MPI',
    'netcdf': 'NetCDF',
    'openmp': 'OpenMP',
    'wxwidgets': 'WxWidgets',
}

def find_external_dependency(name: str, env: 'Environment', kwargs: T.Dict[str, object]) -> T.Union['ExternalDependency', NotFoundDependency]:
    assert(name)
    required = kwargs.get('required', True)
    if not isinstance(required, bool):
        raise DependencyException('Keyword "required" must be a boolean.')
    if not isinstance(kwargs.get('method', ''), str):
        raise DependencyException('Keyword "method" must be a string.')
    lname = name.lower()
    if lname not in _packages_accept_language and 'language' in kwargs:
        raise DependencyException(f'{name} dependency does not accept "language" keyword argument')
    if not isinstance(kwargs.get('version', ''), (str, list)):
        raise DependencyException('Keyword "Version" must be string or list.')

    # display the dependency name with correct casing
    display_name = display_name_map.get(lname, lname)

    for_machine = MachineChoice.BUILD if kwargs.get('native', False) else MachineChoice.HOST

    type_text = PerMachine('Build-time', 'Run-time')[for_machine] + ' dependency'

    # build a list of dependency methods to try
    candidates = _build_external_dependency_list(name, env, for_machine, kwargs)

    pkg_exc: T.List[DependencyException] = []
    pkgdep:  T.List[ExternalDependency]  = []
    details = ''

    for c in candidates:
        # try this dependency method
        try:
            d = c()
            d._check_version()
            pkgdep.append(d)
        except DependencyException as e:
            pkg_exc.append(e)
            mlog.debug(str(e))
        else:
            pkg_exc.append(None)
            details = d.log_details()
            if details:
                details = '(' + details + ') '
            if 'language' in kwargs:
                details += 'for ' + d.language + ' '

            # if the dependency was found
            if d.found():

                info: mlog.TV_LoggableList = []
                if d.version:
                    info.append(mlog.normal_cyan(d.version))

                log_info = d.log_info()
                if log_info:
                    info.append('(' + log_info + ')')

                mlog.log(type_text, mlog.bold(display_name), details + 'found:', mlog.green('YES'), *info)

                return d

    # otherwise, the dependency could not be found
    tried_methods = [d.log_tried() for d in pkgdep if d.log_tried()]
    if tried_methods:
        tried = '{}'.format(mlog.format_list(tried_methods))
    else:
        tried = ''

    mlog.log(type_text, mlog.bold(display_name), details + 'found:', mlog.red('NO'),
             f'(tried {tried})' if tried else '')

    if required:
        # if an exception occurred with the first detection method, re-raise it
        # (on the grounds that it came from the preferred dependency detection
        # method)
        if pkg_exc and pkg_exc[0]:
            raise pkg_exc[0]

        # we have a list of failed ExternalDependency objects, so we can report
        # the methods we tried to find the dependency
        raise DependencyException('Dependency "%s" not found' % (name) +
                                  (', tried %s' % (tried) if tried else ''))

    return NotFoundDependency(env)


def _build_external_dependency_list(name: str, env: 'Environment', for_machine: MachineChoice,
                                    kwargs: T.Dict[str, T.Any]) -> T.List['DependencyGenerator']:
    # First check if the method is valid
    if 'method' in kwargs and kwargs['method'] not in [e.value for e in DependencyMethods]:
        raise DependencyException('method {!r} is invalid'.format(kwargs['method']))

    # Is there a specific dependency detector for this dependency?
    lname = name.lower()
    if lname in packages:
        # Create the list of dependency object constructors using a factory
        # class method, if one exists, otherwise the list just consists of the
        # constructor
        if isinstance(packages[lname], type):
            entry1 = T.cast(T.Type[ExternalDependency], packages[lname])  # mypy doesn't understand isinstance(..., type)
            if issubclass(entry1, ExternalDependency):
                # TODO: somehow make mypy understand that entry1(env, kwargs) is OK...
                func: T.Callable[[], 'ExternalDependency'] = lambda: entry1(env, kwargs)  # type: ignore
                dep = [func]
        else:
            entry2 = T.cast(T.Union['DependencyFactory', 'WrappedFactoryFunc'], packages[lname])
            dep = entry2(env, for_machine, kwargs)
        return dep

    candidates: T.List['DependencyGenerator'] = []

    # If it's explicitly requested, use the dub detection method (only)
    if 'dub' == kwargs.get('method', ''):
        candidates.append(functools.partial(DubDependency, name, env, kwargs))
        return candidates

    # If it's explicitly requested, use the pkgconfig detection method (only)
    if 'pkg-config' == kwargs.get('method', ''):
        candidates.append(functools.partial(PkgConfigDependency, name, env, kwargs))
        return candidates

    # If it's explicitly requested, use the CMake detection method (only)
    if 'cmake' == kwargs.get('method', ''):
        candidates.append(functools.partial(CMakeDependency, name, env, kwargs))
        return candidates

    # If it's explicitly requested, use the Extraframework detection method (only)
    if 'extraframework' == kwargs.get('method', ''):
        # On OSX, also try framework dependency detector
        if env.machines[for_machine].is_darwin():
            candidates.append(functools.partial(ExtraFrameworkDependency, name, env, kwargs))
        return candidates

    # Otherwise, just use the pkgconfig and cmake dependency detector
    if 'auto' == kwargs.get('method', 'auto'):
        candidates.append(functools.partial(PkgConfigDependency, name, env, kwargs))

        # On OSX, also try framework dependency detector
        if env.machines[for_machine].is_darwin():
            candidates.append(functools.partial(ExtraFrameworkDependency, name, env, kwargs))

        # Only use CMake as a last resort, since it might not work 100% (see #6113)
        candidates.append(functools.partial(CMakeDependency, name, env, kwargs))

    return candidates