from __future__ import annotations

import contextlib
import os
import re
import urllib.parse

from pathlib import Path
from typing import TYPE_CHECKING
from typing import Dict
from typing import List
from typing import TypeVar
from typing import Union
from typing import cast

from poetry.core.packages.dependency import Dependency
from tomlkit.items import InlineTable

from poetry.puzzle.provider import Provider


if TYPE_CHECKING:
    from poetry.core.packages.vcs_dependency import VCSDependency

    from poetry.utils.env import Env


DependencySpec = Dict[str, Union[str, bool, Dict[str, Union[str, bool]], List[str]]]


def _parse_dependency_specification_git_url(
    requirement: str, env: Env | None = None
) -> DependencySpec | None:
    from poetry.core.vcs.git import Git
    from poetry.core.vcs.git import ParsedUrl

    parsed = ParsedUrl.parse(requirement)
    url = Git.normalize_url(requirement)

    pair = {"name": parsed.name, "git": url.url}

    if parsed.rev:
        pair["rev"] = url.revision

    if parsed.subdirectory:
        pair["subdirectory"] = parsed.subdirectory

    source_root = env.path.joinpath("src") if env else None
    package = Provider.get_package_from_vcs(
        "git",
        url=url.url,
        rev=pair.get("rev"),
        subdirectory=parsed.subdirectory,
        source_root=source_root,
    )
    pair["name"] = package.name
    return pair


def _parse_dependency_specification_url(
    requirement: str, env: Env | None = None
) -> DependencySpec | None:
    url_parsed = urllib.parse.urlparse(requirement)
    if not (url_parsed.scheme and url_parsed.netloc):
        return None

    if url_parsed.scheme in ["git+https", "git+ssh"]:
        return _parse_dependency_specification_git_url(requirement, env)

    if url_parsed.scheme in ["http", "https"]:
        package = Provider.get_package_from_url(requirement)
        assert package.source_url is not None
        return {"name": package.name, "url": package.source_url}

    return None


def _parse_dependency_specification_path(
    requirement: str, cwd: Path
) -> DependencySpec | None:
    if (os.path.sep in requirement or "/" in requirement) and (
        cwd.joinpath(requirement).exists()
        or Path(requirement).expanduser().exists()
        and Path(requirement).expanduser().is_absolute()
    ):
        path = Path(requirement).expanduser()
        is_absolute = path.is_absolute()

        if not path.is_absolute():
            path = cwd.joinpath(requirement)

        if path.is_file():
            package = Provider.get_package_from_file(path.resolve())
        else:
            package = Provider.get_package_from_directory(path.resolve())

        return {
            "name": package.name,
            "path": (
                path.relative_to(cwd).as_posix() if not is_absolute else path.as_posix()
            ),
        }

    return None


def _parse_dependency_specification_simple(
    requirement: str,
) -> DependencySpec | None:
    extras: list[str] = []
    pair = re.sub("^([^@=: ]+)(?:@|==|(?<![<>~!])=|:| )(.*)$", "\\1 \\2", requirement)
    pair = pair.strip()

    require: DependencySpec = {}

    if " " in pair:
        name, version = pair.split(" ", 1)
        extras_m = re.search(r"\[([\w\d,-_]+)\]$", name)
        if extras_m:
            extras = [e.strip() for e in extras_m.group(1).split(",")]
            name, _ = name.split("[")

        require["name"] = name
        if version != "latest":
            require["version"] = version
    else:
        m = re.match(r"^([^><=!: ]+)((?:>=|<=|>|<|!=|~=|~|\^).*)$", requirement.strip())
        if m:
            name, constraint = m.group(1), m.group(2)
            extras_m = re.search(r"\[([\w\d,-_]+)\]$", name)
            if extras_m:
                extras = [e.strip() for e in extras_m.group(1).split(",")]
                name, _ = name.split("[")

            require["name"] = name
            require["version"] = constraint
        else:
            extras_m = re.search(r"\[([\w\d,-_]+)\]$", pair)
            if extras_m:
                extras = [e.strip() for e in extras_m.group(1).split(",")]
                pair, _ = pair.split("[")

            require["name"] = pair

    if extras:
        require["extras"] = extras

    return require


BaseSpec = TypeVar("BaseSpec", DependencySpec, InlineTable)


def dependency_to_specification(
    dependency: Dependency, specification: BaseSpec
) -> BaseSpec:
    if dependency.is_vcs():
        dependency = cast("VCSDependency", dependency)
        assert dependency.source_url is not None
        specification[dependency.vcs] = dependency.source_url
        if dependency.reference:
            specification["rev"] = dependency.reference
    elif dependency.is_file() or dependency.is_directory():
        assert dependency.source_url is not None
        specification["path"] = dependency.source_url
    elif dependency.is_url():
        assert dependency.source_url is not None
        specification["url"] = dependency.source_url
    elif dependency.pretty_constraint != "*" and not dependency.constraint.is_empty():
        specification["version"] = dependency.pretty_constraint

    if not dependency.marker.is_any():
        specification["markers"] = str(dependency.marker)

    if dependency.extras:
        specification["extras"] = sorted(dependency.extras)

    return specification


def pep508_to_dependency_specification(requirement: str) -> DependencySpec | None:
    if " ; " not in requirement and re.search(r"@[\^~!=<>\d]", requirement):
        # this is of the form package@<semver>, do not attempt to parse it
        return None

    with contextlib.suppress(ValueError):
        dependency = Dependency.create_from_pep_508(requirement)
        specification: DependencySpec = {}
        specification = dependency_to_specification(dependency, specification)

        if specification:
            specification["name"] = dependency.name
            return specification

    return None


def parse_dependency_specification(
    requirement: str, env: Env | None = None, cwd: Path | None = None
) -> DependencySpec:
    requirement = requirement.strip()
    cwd = cwd or Path.cwd()

    specification = pep508_to_dependency_specification(requirement)

    if specification is not None:
        return specification

    extras = []
    extras_m = re.search(r"\[([\w\d,-_ ]+)\]$", requirement)
    if extras_m:
        extras = [e.strip() for e in extras_m.group(1).split(",")]
        requirement, _ = requirement.split("[")

    specification = (
        _parse_dependency_specification_url(requirement, env=env)
        or _parse_dependency_specification_path(requirement, cwd=cwd)
        or _parse_dependency_specification_simple(requirement)
    )

    if specification:
        if extras and "extras" not in specification:
            specification["extras"] = extras
        return specification

    raise ValueError(f"Invalid dependency specification: {requirement}")
