#![cfg_attr(docsrs, feature(doc_cfg))]

#![doc = include_str!("../README.md")]

// @@ begin lint list maintained by maint/add_warning @@

#![allow(renamed_and_removed_lints)] // @@REMOVE_WHEN(ci_arti_stable)

#![allow(unknown_lints)] // @@REMOVE_WHEN(ci_arti_nightly)

#![warn(missing_docs)]

#![warn(noop_method_call)]

#![warn(unreachable_pub)]

#![warn(clippy::all)]

#![deny(clippy::await_holding_lock)]

#![deny(clippy::cargo_common_metadata)]

#![deny(clippy::cast_lossless)]

#![deny(clippy::checked_conversions)]

#![allow(clippy::cognitive_complexity)] // See arti#2556

#![deny(clippy::debug_assert_with_mut_call)]

#![deny(clippy::exhaustive_enums)]

#![deny(clippy::exhaustive_structs)]

#![deny(clippy::expl_impl_clone_on_copy)]

#![deny(clippy::fallible_impl_from)]

#![deny(clippy::implicit_clone)]

#![deny(clippy::large_stack_arrays)]

#![warn(clippy::manual_ok_or)]

#![deny(clippy::missing_docs_in_private_items)]

#![warn(clippy::needless_borrow)]

#![warn(clippy::needless_pass_by_value)]

#![warn(clippy::option_option)]

#![deny(clippy::print_stderr)]

#![deny(clippy::print_stdout)]

#![warn(clippy::rc_buffer)]

#![deny(clippy::ref_option_ref)]

#![warn(clippy::semicolon_if_nothing_returned)]

#![warn(clippy::trait_duplication_in_bounds)]

#![deny(clippy::unchecked_time_subtraction)]

#![deny(clippy::unnecessary_wraps)]

#![warn(clippy::unseparated_literal_suffix)]

#![deny(clippy::unwrap_used)]

#![deny(clippy::mod_module_files)]

#![allow(clippy::let_unit_value)] // This can reasonably be done for explicitness

#![allow(clippy::uninlined_format_args)]

#![allow(clippy::significant_drop_in_scrutinee)] // arti/-/merge_requests/588/#note_2812945

#![allow(clippy::result_large_err)] // temporary workaround for arti#587

#![allow(clippy::needless_raw_string_hashes)] // complained-about code is fine, often best

#![allow(clippy::needless_lifetimes)] // See arti#1765

#![allow(mismatched_lifetime_syntaxes)] // temporary workaround for arti#2060

#![allow(clippy::collapsible_if)] // See arti#2342

#![deny(clippy::unused_async)]

#![deny(clippy::string_slice)] // See arti#2571

#![allow(recursion_depth_exceeding_limit)] // arti#2715, rust/issues/159228

//! <!-- @@ end lint list maintained by maint/add_warning @@ -->

use std::collections::HashMap;

use std::path::{Path, PathBuf};

use serde::{Deserialize, Serialize};

use std::borrow::Cow;

#[cfg(feature = "expand-paths")]

use {directories::BaseDirs, std::sync::LazyLock};

use tor_error::{ErrorKind, HasKind};

#[cfg(all(test, feature = "expand-paths"))]

use std::ffi::OsStr;

#[cfg(feature = "address")]

pub mod addr;

#[cfg(feature = "arti-client")]

mod arti_client_paths;

#[cfg(feature = "arti-client")]

pub use arti_client_paths::arti_client_base_resolver;

/// A path in a configuration file: tilde expansion is performed, along

/// with expansion of variables provided by a [`CfgPathResolver`].

///

/// The tilde expansion is performed using the home directory given by the

/// `directories` crate, which may be based on an environment variable. For more

/// information, see [`BaseDirs::home_dir`](directories::BaseDirs::home_dir).

///

/// Alternatively, a `CfgPath` can contain literal `PathBuf`, which will not be expanded.

#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq)]

#[serde(transparent)]

pub struct CfgPath(PathInner);

/// Inner implementation of CfgPath

///

/// `PathInner` exists to avoid making the variants part of the public Rust API

#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq)]

#[serde(untagged)]

enum PathInner {

    /// A path that should be used literally, with no expansion.

    Literal(LiteralPath),

    /// A path that should be expanded from a string using ShellExpand.

    Shell(String),

}

#[derive(Clone, Debug, Serialize, Deserialize, Eq, PartialEq)]

/// Inner implementation of PathInner:Literal

///

/// `LiteralPath` exists to arrange that `PathInner::Literal`'s (de)serialization

/// does not overlap with `PathInner::Shell`'s.

struct LiteralPath {

    /// The underlying `PathBuf`.

    literal: PathBuf,

}

/// An error that has occurred while expanding a path.

#[derive(thiserror::Error, Debug, Clone)]

#[non_exhaustive]

#[cfg_attr(test, derive(PartialEq))]

pub enum CfgPathError {

    /// The path contained a variable we didn't recognize.

    #[error("Unrecognized variable {0} in path")]

    UnknownVar(String),

    /// We couldn't construct a ProjectDirs object.

    #[error(

        "Couldn't determine XDG Project Directories, needed to resolve a path; probably, unable to determine HOME directory"

    )]

    NoProjectDirs,

    /// We couldn't construct a BaseDirs object.

    #[error("Can't construct base directories to resolve a path element")]

    NoBaseDirs,

    /// We couldn't find our current binary path.

    #[error("Can't find the path to the current binary")]

    NoProgramPath,

    /// We couldn't find the directory path containing the current binary.

    #[error("Can't find the directory of the current binary")]

    NoProgramDir,

    /// We couldn't convert a string to a valid path on the OS.

    //

    // NOTE: This is not currently generated. Shall we remove it?

    #[error("Invalid path string: {0:?}")]

    InvalidString(String),

    /// Variable interpolation (`$`) attempted, but not compiled in

    #[error(

        "Variable interpolation $ is not supported (tor-config/expand-paths feature disabled)); $ must still be doubled"

    )]

    VariableInterpolationNotSupported(String),

    /// Home dir interpolation (`~`) attempted, but not compiled in

    #[error("Home dir ~/ is not supported (tor-config/expand-paths feature disabled)")]

    HomeDirInterpolationNotSupported(String),

}

impl HasKind for CfgPathError {

        use CfgPathError as E;

        use ErrorKind as EK;

            E::VariableInterpolationNotSupported(_) | E::HomeDirInterpolationNotSupported(_) => {

            }

        }

}

/// A variable resolver for paths in a configuration file.

///

/// Typically there should be one resolver per application, and the application should share the

/// resolver throughout the application to have consistent path variable expansions. Typically the

/// application would create its own resolver with its application-specific variables, but note that

/// `TorClientConfig` is an exception which does not accept a resolver from the application and

/// instead generates its own. This is done for backwards compatibility reasons.

///

/// Once constructed, they are used during calls to [`CfgPath::path`] to expand variables in the

/// path.

#[derive(Clone, Debug, Default)]

pub struct CfgPathResolver {

    /// The variables and their values. The values can be an `Err` if the variable is expected but

    /// can't be expanded.

    vars: HashMap<String, Result<Cow<'static, Path>, CfgPathError>>,

}

impl CfgPathResolver {

    /// Get the value for a given variable name.

    #[cfg(feature = "expand-paths")]

        }

    /// Set a variable `var` that will be replaced with `val` when a [`CfgPath`] is expanded.

    ///

    /// Setting an `Err` is useful when a variable is supported, but for whatever reason it can't be

    /// expanded, and you'd like to return a more-specific error. An example might be a `USER_HOME`

    /// variable for a user that doesn't have a `HOME` environment variable set.

    ///

    /// ```

    /// use std::path::Path;

    /// use tor_config_path::{CfgPath, CfgPathResolver};

    ///

    /// let mut path_resolver = CfgPathResolver::default();

    /// path_resolver.set_var("FOO", Ok(Path::new("/foo").to_owned().into()));

    ///

    /// let path = CfgPath::new("${FOO}/bar".into());

    ///

    /// #[cfg(feature = "expand-paths")]

    /// assert_eq!(path.path(&path_resolver).unwrap(), Path::new("/foo/bar"));

    /// #[cfg(not(feature = "expand-paths"))]

    /// assert!(path.path(&path_resolver).is_err());

    /// ```

    /// Helper to create a `CfgPathResolver` from str `(name, value)` pairs.

    #[cfg(all(test, feature = "expand-paths"))]

    {

}

impl CfgPath {

    /// Create a new configuration path

    /// Construct a new `CfgPath` designating a literal not-to-be-expanded `PathBuf`

    /// Return the path on disk designated by this `CfgPath`.

    ///

    /// Variables may or may not be resolved using `path_resolver`, depending on whether the

    /// `expand-paths` feature is enabled or not.

        }

    /// If the `CfgPath` is a string that should be expanded, return the (unexpanded) string,

    ///

    /// Before use, this string would have be to expanded.  So if you want a path to actually use,

    /// call `path` instead.

    ///

    /// Returns `None` if the `CfgPath` is a literal `PathBuf` not intended for expansion.

        }

    /// If the `CfgPath` designates a literal not-to-be-expanded `Path`, return a reference to it

    ///

    /// Returns `None` if the `CfgPath` is a string which should be expanded, which is the

    /// usual case.

        }

}

impl std::fmt::Display for CfgPath {

        }

}

/// Return the user's home directory used when expanding paths.

// This is public so that applications which want to support for example a `USER_HOME` variable can

// use the same home directory expansion that we use in this crate for `~` expansion.

#[cfg(feature = "expand-paths")]

    /// Lazy lock holding the home directory.

    static HOME_DIR: LazyLock<Option<PathBuf>> =

/// Helper: expand a directory given as a string.

#[cfg(feature = "expand-paths")]

    );

/// Helper: convert a string to a path without expansion.

#[cfg(not(feature = "expand-paths"))]

fn expand(input: &str, _: &CfgPathResolver) -> Result<PathBuf, CfgPathError> {

    // We must still de-duplicate `$` and reject `~/`,, so that the behaviour is a superset

    if input.starts_with('~') {

        return Err(CfgPathError::HomeDirInterpolationNotSupported(input.into()));

    }

    let mut out = String::with_capacity(input.len());

    let mut s = input;

    while let Some((lhs, rhs)) = s.split_once('$') {

        if let Some(rhs) = rhs.strip_prefix('$') {

            // deduplicate the $

            out += lhs;

            out += "$";

            s = rhs;

        } else {

            return Err(CfgPathError::VariableInterpolationNotSupported(

                input.into(),

            ));

        }

    }

    out += s;

    Ok(out.into())

}

#[cfg(all(test, feature = "expand-paths"))]

mod test {

    #![allow(clippy::unwrap_used)]

    use super::*;

    #[test]

    fn expand_no_op() {

        let r = CfgPathResolver::from_pairs([("FOO", "foo")]);

        let p = CfgPath::new("Hello/world".to_string());

        assert_eq!(p.to_string(), "Hello/world".to_string());

        assert_eq!(p.path(&r).unwrap().to_str(), Some("Hello/world"));

        let p = CfgPath::new("/usr/local/foo".to_string());

        assert_eq!(p.to_string(), "/usr/local/foo".to_string());

        assert_eq!(p.path(&r).unwrap().to_str(), Some("/usr/local/foo"));

    }

    #[cfg(not(target_family = "windows"))]

    #[test]

    fn expand_home() {

        let r = CfgPathResolver::from_pairs([("USER_HOME", home().unwrap())]);

        let p = CfgPath::new("~/.arti/config".to_string());

        assert_eq!(p.to_string(), "~/.arti/config".to_string());

        let expected = dirs::home_dir().unwrap().join(".arti/config");

        assert_eq!(p.path(&r).unwrap().to_str(), expected.to_str());

        let p = CfgPath::new("${USER_HOME}/.arti/config".to_string());

        assert_eq!(p.to_string(), "${USER_HOME}/.arti/config".to_string());

        assert_eq!(p.path(&r).unwrap().to_str(), expected.to_str());

    }

    #[cfg(target_family = "windows")]

    #[test]

    fn expand_home() {

        let r = CfgPathResolver::from_pairs([("USER_HOME", home().unwrap())]);

        let p = CfgPath::new("~\\.arti\\config".to_string());

        assert_eq!(p.to_string(), "~\\.arti\\config".to_string());

        let expected = dirs::home_dir().unwrap().join(".arti\\config");

        assert_eq!(p.path(&r).unwrap().to_str(), expected.to_str());

        let p = CfgPath::new("${USER_HOME}\\.arti\\config".to_string());

        assert_eq!(p.to_string(), "${USER_HOME}\\.arti\\config".to_string());

        assert_eq!(p.path(&r).unwrap().to_str(), expected.to_str());

    }

    #[test]

    fn expand_bogus() {

        let r = CfgPathResolver::from_pairs([("FOO", "foo")]);

        let p = CfgPath::new("${ARTI_WOMBAT}/example".to_string());

        assert_eq!(p.to_string(), "${ARTI_WOMBAT}/example".to_string());

        assert!(matches!(p.path(&r), Err(CfgPathError::UnknownVar(_))));

        assert_eq!(

            &p.path(&r).unwrap_err().to_string(),

            "Unrecognized variable ARTI_WOMBAT in path"

        );

    }

    #[test]

    fn literal() {

        let r = CfgPathResolver::from_pairs([("ARTI_CACHE", "foo")]);

        let p = CfgPath::new_literal(PathBuf::from("${ARTI_CACHE}/literally"));

        // This doesn't get expanded, since we're using a literal path.

        assert_eq!(

            p.path(&r).unwrap().to_str().unwrap(),

            "${ARTI_CACHE}/literally"

        );

        assert_eq!(p.to_string(), "\"${ARTI_CACHE}/literally\" [exactly]");

    }

    #[test]

    #[cfg(feature = "expand-paths")]

    fn program_dir() {

        let current_exe = std::env::current_exe().unwrap();

        let r = CfgPathResolver::from_pairs([("PROGRAM_DIR", current_exe.parent().unwrap())]);

        let p = CfgPath::new("${PROGRAM_DIR}/foo".to_string());

        let mut this_binary = current_exe;

        this_binary.pop();

        this_binary.push("foo");

        let expanded = p.path(&r).unwrap();

        assert_eq!(expanded, this_binary);

    }

    #[test]

    #[cfg(not(feature = "expand-paths"))]

    fn rejections() {

        let r = CfgPathResolver::from_pairs([("PROGRAM_DIR", std::env::current_exe().unwrap())]);

        let chk_err = |s: &str, mke: &dyn Fn(String) -> CfgPathError| {

            let p = CfgPath::new(s.to_string());

            assert_eq!(p.path(&r).unwrap_err(), mke(s.to_string()));

        };

        let chk_ok = |s: &str, exp| {

            let p = CfgPath::new(s.to_string());

            assert_eq!(p.path(&r), Ok(PathBuf::from(exp)));

        };

        chk_err(

            "some/${PROGRAM_DIR}/foo",

            &CfgPathError::VariableInterpolationNotSupported,

        );

        chk_err("~some", &CfgPathError::HomeDirInterpolationNotSupported);

        chk_ok("some$$foo$$bar", "some$foo$bar");

        chk_ok("no dollars", "no dollars");

    }

}

#[cfg(test)]

mod test_serde {

    // @@ begin test lint list maintained by maint/add_warning @@

    #![allow(clippy::bool_assert_comparison)]

    #![allow(clippy::clone_on_copy)]

    #![allow(clippy::dbg_macro)]

    #![allow(clippy::mixed_attributes_style)]

    #![allow(clippy::print_stderr)]

    #![allow(clippy::print_stdout)]

    #![allow(clippy::single_char_pattern)]

    #![allow(clippy::unwrap_used)]

    #![allow(clippy::unchecked_time_subtraction)]

    #![allow(clippy::useless_vec)]

    #![allow(clippy::needless_pass_by_value)]

    #![allow(clippy::string_slice)] // See arti#2571

    //! <!-- @@ end test lint list maintained by maint/add_warning @@ -->

    use super::*;

    use std::ffi::OsString;

    use std::fmt::Debug;

    use derive_deftly::Deftly;

    use tor_config::load::TopLevel;

    #[derive(Serialize, Deserialize, Deftly, Eq, PartialEq, Debug)]

    #[derive_deftly(tor_config::derive::TorConfig)]

    #[deftly(tor_config(no_default_trait))]

    struct TestConfigFile {

        #[deftly(tor_config(no_default))]

        p: CfgPath,

    }

    impl TopLevel for TestConfigFile {

        type Builder = TestConfigFileBuilder;

    }

    fn deser_json(json: &str) -> CfgPath {

        dbg!(json);

        let TestConfigFile { p } = serde_json::from_str(json).expect("deser json failed");

        p

    }

    fn deser_toml(toml: &str) -> CfgPath {

        dbg!(toml);

        let TestConfigFile { p } = toml::from_str(toml).expect("deser toml failed");

        p

    }

    fn deser_toml_cfg(toml: &str) -> CfgPath {

        dbg!(toml);

        let mut sources = tor_config::ConfigurationSources::new_empty();

        sources.push_source(

            tor_config::ConfigurationSource::from_verbatim(toml.to_string()),

            tor_config::sources::MustRead::MustRead,

        );

        let cfg = sources.load().unwrap();

        dbg!(&cfg);

        let TestConfigFile { p } = tor_config::load::resolve(cfg).expect("cfg resolution failed");

        p

    }

    #[test]

    fn test_parse() {

        fn desers(toml: &str, json: &str) -> Vec<CfgPath> {

            vec![deser_toml(toml), deser_toml_cfg(toml), deser_json(json)]

        }

        for cp in desers(r#"p = "string""#, r#"{ "p": "string" }"#) {

            assert_eq!(cp.as_unexpanded_str(), Some("string"));

            assert_eq!(cp.as_literal_path(), None);

        }

        for cp in desers(

            r#"p = { literal = "lit" }"#,

            r#"{ "p": {"literal": "lit"} }"#,

        ) {

            assert_eq!(cp.as_unexpanded_str(), None);

            assert_eq!(cp.as_literal_path(), Some(&*PathBuf::from("lit")));

        }

    }

    fn non_string_path() -> PathBuf {

        #[cfg(target_family = "unix")]

        {

            use std::os::unix::ffi::OsStringExt;

            return PathBuf::from(OsString::from_vec(vec![0x80_u8]));

        }

        #[cfg(target_family = "windows")]

        {

            use std::os::windows::ffi::OsStringExt;

            return PathBuf::from(OsString::from_wide(&[0xD800_u16]));

        }

        #[allow(unreachable_code)]

        // Cannot test non-Stringy Paths on this platform

        PathBuf::default()

    }

    fn test_roundtrip_cases<SER, S, DESER, E, F>(ser: SER, deser: DESER)

    where

        SER: Fn(&TestConfigFile) -> Result<S, E>,

        DESER: Fn(&S) -> Result<TestConfigFile, F>,

        S: Debug,

        E: Debug,

        F: Debug,

    {

        let case = |easy, p| {

            let input = TestConfigFile { p };

            let s = match ser(&input) {

                Ok(s) => s,

                Err(e) if easy => panic!("ser failed {:?} e={:?}", input, e),

                Err(_) => return,

            };

            dbg!(&input, &s);

            let output = deser(&s).expect("deser failed");

            assert_eq!(&input, &output, "s={:?}", s);

        };

        case(true, CfgPath::new("string".into()));

        case(true, CfgPath::new_literal(PathBuf::from("nice path")));

        case(true, CfgPath::new_literal(PathBuf::from("path with ✓")));

        // Non-UTF-8 paths are really hard to serialize.  We allow the serializsaton

        // to fail, and if it does, we skip the rest of the round trip test.

        // But, if they did serialise, we want to make sure that we can deserialize.

        // Hence this test case.

        case(false, CfgPath::new_literal(non_string_path()));

    }

    #[test]

    fn roundtrip_json() {

        test_roundtrip_cases(

            |input| serde_json::to_string(&input),

            |json| serde_json::from_str(json),

        );

    }

    #[test]

    fn roundtrip_toml() {

        test_roundtrip_cases(|input| toml::to_string(&input), |toml| toml::from_str(toml));

    }

    #[test]

    fn roundtrip_mpack() {

        test_roundtrip_cases(

            |input| rmp_serde::to_vec(&input),

            |mpack| rmp_serde::from_slice(mpack),

        );

    }

}