# 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.

# This file contains the base representation for import('modname')

from __future__ import annotations
import dataclasses
import typing as T

from .. import mesonlib
from ..mesonlib import relpath, HoldableObject, MachineChoice
from ..interpreterbase.decorators import noKwargs, noPosargs
from ..programs import ExternalProgram

if T.TYPE_CHECKING:
    from .. import build
    from ..interpreter import Interpreter
    from ..interpreter.interpreterobjects import MachineHolder
    from ..interpreterbase import TYPE_var, TYPE_kwargs
    from ..programs import OverrideProgram
    from ..wrap import WrapMode
    from ..build import EnvironmentVariables, Executable
    from ..dependencies import Dependency

class ModuleState:
    """Object passed to all module methods.

    This is a WIP API provided to modules, it should be extended to have everything
    needed so modules does not touch any other part of Meson internal APIs.
    """

    def __init__(self, interpreter: 'Interpreter') -> None:
        # Keep it private, it should be accessed only through methods.
        self._interpreter = interpreter

        self.source_root = interpreter.environment.get_source_dir()
        self.build_to_src = relpath(interpreter.environment.get_source_dir(),
                                    interpreter.environment.get_build_dir())
        self.subproject = interpreter.subproject
        self.subdir = interpreter.subdir
        self.current_lineno = interpreter.current_lineno
        self.environment = interpreter.environment
        self.project_name = interpreter.build.project_name
        self.project_version = interpreter.build.dep_manifest[interpreter.active_projectname].version
        # The backend object is under-used right now, but we will need it:
        # https://github.com/mesonbuild/meson/issues/1419
        self.backend = interpreter.backend
        self.targets = interpreter.build.targets
        self.data = interpreter.build.data
        self.headers = interpreter.build.get_headers()
        self.man = interpreter.build.get_man()
        self.global_args = interpreter.build.global_args.host
        self.project_args = interpreter.build.projects_args.host.get(interpreter.subproject, {})
        self.build_machine = T.cast('MachineHolder', interpreter.builtin['build_machine']).held_object
        self.host_machine = T.cast('MachineHolder', interpreter.builtin['host_machine']).held_object
        self.target_machine = T.cast('MachineHolder', interpreter.builtin['target_machine']).held_object
        self.current_node = interpreter.current_node

    def get_include_args(self, include_dirs: T.Iterable[T.Union[str, build.IncludeDirs]], prefix: str = '-I') -> T.List[str]:
        if not include_dirs:
            return []

        srcdir = self.environment.get_source_dir()
        builddir = self.environment.get_build_dir()

        dirs_str: T.List[str] = []
        for dirs in include_dirs:
            if isinstance(dirs, str):
                dirs_str += [f'{prefix}{dirs}']
            else:
                dirs_str.extend([f'{prefix}{i}' for i in dirs.to_string_list(srcdir, builddir)])
                dirs_str.extend([f'{prefix}{i}' for i in dirs.get_extra_build_dirs()])

        return dirs_str

    def find_program(self, prog: T.Union[str, T.List[str]], required: bool = True,
                     version_func: T.Optional[T.Callable[['ExternalProgram'], str]] = None,
                     wanted: T.Optional[str] = None, silent: bool = False,
                     for_machine: MachineChoice = MachineChoice.HOST) -> 'ExternalProgram':
        return self._interpreter.find_program_impl(prog, required=required, version_func=version_func,
                                                   wanted=wanted, silent=silent, for_machine=for_machine)

    def find_tool(self, name: str, depname: str, varname: str, required: bool = True,
                  wanted: T.Optional[str] = None) -> T.Union['Executable', ExternalProgram, 'OverrideProgram']:
        # Look in overrides in case it's built as subproject
        progobj = self._interpreter.program_from_overrides([name], [])
        if progobj is not None:
            return progobj

        # Look in machine file
        prog_list = self.environment.lookup_binary_entry(MachineChoice.HOST, name)
        if prog_list is not None:
            return ExternalProgram.from_entry(name, prog_list)

        # Check if pkgconfig has a variable
        dep = self.dependency(depname, native=True, required=False, wanted=wanted)
        if dep.found() and dep.type_name == 'pkgconfig':
            value = dep.get_variable(pkgconfig=varname)
            if value:
                return ExternalProgram(name, [value])

        # Normal program lookup
        return self.find_program(name, required=required, wanted=wanted)

    def dependency(self, depname: str, native: bool = False, required: bool = True,
                   wanted: T.Optional[str] = None) -> 'Dependency':
        kwargs = {'native': native, 'required': required}
        if wanted:
            kwargs['version'] = wanted
        # FIXME: Even if we fix the function, mypy still can't figure out what's
        # going on here. And we really dont want to call interpreter
        # implementations of meson functions anyway.
        return self._interpreter.func_dependency(self.current_node, [depname], kwargs) # type: ignore

    def test(self, args: T.Tuple[str, T.Union[build.Executable, build.Jar, 'ExternalProgram', mesonlib.File]],
             workdir: T.Optional[str] = None,
             env: T.Union[T.List[str], T.Dict[str, str], str] = None,
             depends: T.List[T.Union[build.CustomTarget, build.BuildTarget]] = None) -> None:
        kwargs = {'workdir': workdir,
                  'env': env,
                  'depends': depends,
                  }
        # typed_* takes a list, and gives a tuple to func_test. Violating that constraint
        # makes the universe (or at least use of this function) implode
        real_args = list(args)
        # TODO: Use interpreter internal API, but we need to go through @typed_kwargs
        self._interpreter.func_test(self.current_node, real_args, kwargs)

    def get_option(self, name: str, subproject: str = '',
                   machine: MachineChoice = MachineChoice.HOST,
                   lang: T.Optional[str] = None,
                   module: T.Optional[str] = None) -> T.Union[str, int, bool, 'WrapMode']:
        return self.environment.coredata.get_option(mesonlib.OptionKey(name, subproject, machine, lang, module))

    def is_user_defined_option(self, name: str, subproject: str = '',
                               machine: MachineChoice = MachineChoice.HOST,
                               lang: T.Optional[str] = None,
                               module: T.Optional[str] = None) -> bool:
        key = mesonlib.OptionKey(name, subproject, machine, lang, module)
        return key in self._interpreter.user_defined_options.cmd_line_options


class ModuleObject(HoldableObject):
    """Base class for all objects returned by modules
    """
    def __init__(self) -> None:
        self.methods: T.Dict[
            str,
            T.Callable[[ModuleState, T.List['TYPE_var'], 'TYPE_kwargs'], T.Union[ModuleReturnValue, 'TYPE_var']]
        ] = {}


class MutableModuleObject(ModuleObject):
    pass


@dataclasses.dataclass
class ModuleInfo:

    """Metadata about a Module."""

    name: str
    added: T.Optional[str] = None
    deprecated: T.Optional[str] = None
    unstable: bool = False
    stabilized: T.Optional[str] = None


class NewExtensionModule(ModuleObject):

    """Class for modern modules

    provides the found method.
    """

    INFO: ModuleInfo

    def __init__(self) -> None:
        super().__init__()
        self.methods.update({
            'found': self.found_method,
        })

    @noPosargs
    @noKwargs
    def found_method(self, state: 'ModuleState', args: T.List['TYPE_var'], kwargs: 'TYPE_kwargs') -> bool:
        return self.found()

    @staticmethod
    def found() -> bool:
        return True

    def get_devenv(self) -> T.Optional['EnvironmentVariables']:
        return None

# FIXME: Port all modules to stop using self.interpreter and use API on
# ModuleState instead. Modules should stop using this class and instead use
# ModuleObject base class.
class ExtensionModule(NewExtensionModule):
    def __init__(self, interpreter: 'Interpreter') -> None:
        super().__init__()
        self.interpreter = interpreter

class NotFoundExtensionModule(NewExtensionModule):

    """Class for modern modules

    provides the found method.
    """

    def __init__(self, name: str) -> None:
        super().__init__()
        self.INFO = ModuleInfo(name)

    @staticmethod
    def found() -> bool:
        return False


def is_module_library(fname):
    '''
    Check if the file is a library-like file generated by a module-specific
    target, such as GirTarget or TypelibTarget
    '''
    if hasattr(fname, 'fname'):
        fname = fname.fname
    suffix = fname.split('.')[-1]
    return suffix in ('gir', 'typelib')


class ModuleReturnValue:
    def __init__(self, return_value: T.Optional['TYPE_var'],
                 new_objects: T.Sequence[T.Union['TYPE_var', 'build.ExecutableSerialisation']]) -> None:
        self.return_value = return_value
        assert isinstance(new_objects, list)
        self.new_objects: T.List[T.Union['TYPE_var', 'build.ExecutableSerialisation']] = new_objects