# Copyright 2019 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 __future__ import annotations
import typing as T

from . import ExtensionModule, ModuleObject, MutableModuleObject
from .. import build
from .. import dependencies
from .. import mesonlib
from ..interpreterbase import (
    noPosargs, noKwargs,
    InterpreterException, InvalidArguments, InvalidCode, FeatureNew,
)
from ..interpreterbase.decorators import ContainerTypeInfo, KwargInfo, typed_kwargs, typed_pos_args
from ..mesonlib import OrderedSet

if T.TYPE_CHECKING:
    from typing_extensions import TypedDict

    from . import ModuleState
    from ..interpreter import Interpreter
    from ..interpreterbase import TYPE_var, TYPE_kwargs

    class AddKwargs(TypedDict):

        when: T.List[T.Union[str, dependencies.Dependency]]
        if_true: T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes, dependencies.Dependency]]
        if_false: T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes]]

    class AddAllKw(TypedDict):

        when: T.List[T.Union[str, dependencies.Dependency]]
        if_true: T.List[SourceSetImpl]

    class ApplyKw(TypedDict):

        strict: bool


_WHEN_KW: KwargInfo[T.List[T.Union[str, dependencies.Dependency]]] = KwargInfo(
    'when',
    ContainerTypeInfo(list, (str, dependencies.Dependency)),
    listify=True,
    default=[],
)


class SourceSetRule(T.NamedTuple):
    keys: T.List[str]
    """Configuration keys that enable this rule if true"""

    deps: T.List[dependencies.Dependency]
    """Dependencies that enable this rule if true"""

    sources: T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes]]
    """Source files added when this rule's conditions are true"""

    extra_deps: T.List[dependencies.Dependency]
    """Dependencies added when this rule's conditions are true, but
       that do not make the condition false if they're absent."""

    sourcesets: T.List[SourceSetImpl]
    """Other sourcesets added when this rule's conditions are true"""

    if_false: T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes]]
    """Source files added when this rule's conditons are false"""


class SourceFiles(T.NamedTuple):
    sources: OrderedSet[T.Union[mesonlib.FileOrString, build.GeneratedTypes]]
    deps: OrderedSet[dependencies.Dependency]


class SourceSet:
    """Base class to avoid circular references.

    Because of error messages, this class is called SourceSet, and the actual
    implementation is an Impl.
    """


class SourceSetImpl(SourceSet, MutableModuleObject):
    def __init__(self, interpreter: Interpreter):
        super().__init__()
        self.rules: T.List[SourceSetRule] = []
        self.subproject = interpreter.subproject
        self.environment = interpreter.environment
        self.subdir = interpreter.subdir
        self.frozen = False
        self.methods.update({
            'add': self.add_method,
            'add_all': self.add_all_method,
            'all_sources': self.all_sources_method,
            'all_dependencies': self.all_dependencies_method,
            'apply': self.apply_method,
        })

    def check_source_files(self, args: T.Sequence[T.Union[mesonlib.FileOrString, build.GeneratedTypes, dependencies.Dependency]],
                           ) -> T.Tuple[T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes]], T.List[dependencies.Dependency]]:
        sources: T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes]] = []
        deps: T.List[dependencies.Dependency] = []
        for x in args:
            if isinstance(x, dependencies.Dependency):
                deps.append(x)
            else:
                sources.append(x)
        to_check: T.List[str] = []

        # Get the actual output names to check
        for s in sources:
            if isinstance(s, str):
                to_check.append(s)
            elif isinstance(s, mesonlib.File):
                to_check.append(s.fname)
            else:
                to_check.extend(s.get_outputs())
        mesonlib.check_direntry_issues(to_check)
        return sources, deps

    def check_conditions(self, args: T.Sequence[T.Union[str, dependencies.Dependency]]
                         ) -> T.Tuple[T.List[str], T.List[dependencies.Dependency]]:
        keys: T.List[str] = []
        deps: T.List[dependencies.Dependency] = []
        for x in args:
            if isinstance(x, str):
                keys.append(x)
            else:
                deps.append(x)
        return keys, deps

    @typed_pos_args('sourceset.add', varargs=(str, mesonlib.File, build.GeneratedList, build.CustomTarget, build.CustomTargetIndex, dependencies.Dependency))
    @typed_kwargs(
        'sourceset.add',
        _WHEN_KW,
        KwargInfo(
            'if_true',
            ContainerTypeInfo(list, (str, mesonlib.File, build.GeneratedList, build.CustomTarget, build.CustomTargetIndex, dependencies.Dependency)),
            listify=True,
            default=[],
        ),
        KwargInfo(
            'if_false',
            ContainerTypeInfo(list, (str, mesonlib.File, build.GeneratedList, build.CustomTarget, build.CustomTargetIndex)),
            listify=True,
            default=[],
        ),
    )
    def add_method(self, state: ModuleState,
                   args: T.Tuple[T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes, dependencies.Dependency]]],
                   kwargs: AddKwargs) -> None:
        if self.frozen:
            raise InvalidCode('Tried to use \'add\' after querying the source set')
        when = kwargs['when']
        if_true = kwargs['if_true']
        if_false = kwargs['if_false']
        if not any([when, if_true, if_false]):
            if_true = args[0]
        elif args[0]:
            raise InterpreterException('add called with both positional and keyword arguments')
        keys, dependencies = self.check_conditions(when)
        sources, extra_deps = self.check_source_files(if_true)
        if_false, _ = self.check_source_files(if_false)
        self.rules.append(SourceSetRule(keys, dependencies, sources, extra_deps, [], if_false))

    @typed_pos_args('sourceset.add_all', varargs=SourceSet)
    @typed_kwargs(
        'sourceset.add_all',
        _WHEN_KW,
        KwargInfo(
            'if_true',
            ContainerTypeInfo(list, SourceSet),
            listify=True,
            default=[],
        )
    )
    def add_all_method(self, state: ModuleState, args: T.Tuple[T.List[SourceSetImpl]],
                       kwargs: AddAllKw) -> None:
        if self.frozen:
            raise InvalidCode('Tried to use \'add_all\' after querying the source set')
        when = kwargs['when']
        if_true = kwargs['if_true']
        if not when and not if_true:
            if_true = args[0]
        elif args[0]:
            raise InterpreterException('add_all called with both positional and keyword arguments')
        keys, dependencies = self.check_conditions(when)
        for s in if_true:
            if not isinstance(s, SourceSetImpl):
                raise InvalidCode('Arguments to \'add_all\' after the first must be source sets')
            s.frozen = True
        self.rules.append(SourceSetRule(keys, dependencies, [], [], if_true, []))

    def collect(self, enabled_fn: T.Callable[[str], bool],
                all_sources: bool,
                into: T.Optional['SourceFiles'] = None) -> SourceFiles:
        if not into:
            into = SourceFiles(OrderedSet(), OrderedSet())
        for entry in self.rules:
            if all(x.found() for x in entry.deps) and \
               all(enabled_fn(key) for key in entry.keys):
                into.sources.update(entry.sources)
                into.deps.update(entry.deps)
                into.deps.update(entry.extra_deps)
                for ss in entry.sourcesets:
                    ss.collect(enabled_fn, all_sources, into)
                if not all_sources:
                    continue
            into.sources.update(entry.if_false)
        return into

    @noKwargs
    @noPosargs
    def all_sources_method(self, state: ModuleState, args: T.List[TYPE_var], kwargs: TYPE_kwargs
                           ) -> T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes]]:
        self.frozen = True
        files = self.collect(lambda x: True, True)
        return list(files.sources)

    @noKwargs
    @noPosargs
    @FeatureNew('source_set.all_dependencies() method', '0.52.0')
    def all_dependencies_method(self, state: ModuleState, args: T.List[TYPE_var], kwargs: TYPE_kwargs
                                ) -> T.List[dependencies.Dependency]:
        self.frozen = True
        files = self.collect(lambda x: True, True)
        return list(files.deps)

    @typed_pos_args('sourceset.apply', (build.ConfigurationData, dict))
    @typed_kwargs('sourceset.apply', KwargInfo('strict', bool, default=True))
    def apply_method(self, state: ModuleState, args: T.Tuple[T.Union[build.ConfigurationData, T.Dict[str, TYPE_var]]], kwargs: ApplyKw) -> SourceFilesObject:
        config_data = args[0]
        self.frozen = True
        strict = kwargs['strict']
        if isinstance(config_data, dict):
            def _get_from_config_data(key: str) -> bool:
                assert isinstance(config_data, dict), 'for mypy'
                if strict and key not in config_data:
                    raise InterpreterException(f'Entry {key} not in configuration dictionary.')
                return bool(config_data.get(key, False))
        else:
            config_cache: T.Dict[str, bool] = {}

            def _get_from_config_data(key: str) -> bool:
                assert isinstance(config_data, build.ConfigurationData), 'for mypy'
                if key not in config_cache:
                    if key in config_data:
                        config_cache[key] = bool(config_data.get(key)[0])
                    elif strict:
                        raise InvalidArguments(f'sourceset.apply: key "{key}" not in passed configuration, and strict set.')
                    else:
                        config_cache[key] = False
                return config_cache[key]

        files = self.collect(_get_from_config_data, False)
        res = SourceFilesObject(files)
        return res

class SourceFilesObject(ModuleObject):
    def __init__(self, files: SourceFiles):
        super().__init__()
        self.files = files
        self.methods.update({
            'sources': self.sources_method,
            'dependencies': self.dependencies_method,
        })

    @noPosargs
    @noKwargs
    def sources_method(self, state: ModuleState, args: T.List[TYPE_var], kwargs: TYPE_kwargs
                       ) -> T.List[T.Union[mesonlib.FileOrString, build.GeneratedTypes]]:
        return list(self.files.sources)

    @noPosargs
    @noKwargs
    def dependencies_method(self, state: ModuleState, args: T.List[TYPE_var], kwargs: TYPE_kwargs
                            ) -> T.List[dependencies.Dependency]:
        return list(self.files.deps)

class SourceSetModule(ExtensionModule):
    @FeatureNew('SourceSet module', '0.51.0')
    def __init__(self, interpreter: Interpreter):
        super().__init__(interpreter)
        self.methods.update({
            'source_set': self.source_set,
        })

    @noKwargs
    @noPosargs
    def source_set(self, state: ModuleState, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> SourceSetImpl:
        return SourceSetImpl(self.interpreter)

def initialize(interp: Interpreter) -> SourceSetModule:
    return SourceSetModule(interp)