//! The Arti key store.

//!

//! See the [`ArtiNativeKeystore`] docs for more details.

pub(crate) mod certs;

pub(crate) mod err;

pub(crate) mod ssh;

use std::io::{self};

use std::path::Path;

use std::result::Result as StdResult;

use std::str::FromStr;

use std::sync::Arc;

use crate::keystore::fs_utils::{checked_op, FilesystemAction, FilesystemError, RelKeyPath};

use crate::keystore::{EncodableItem, ErasedKey, KeySpecifier, Keystore};

use crate::{

    arti_path, ArtiPath, ArtiPathUnavailableError, KeyPath, KeystoreId, Result,

    UnknownKeyTypeError, UnrecognizedEntryError, UnrecognizedEntryId,

};

use certs::UnparsedCert;

use err::ArtiNativeKeystoreError;

use ssh::UnparsedOpenSshKey;

use fs_mistrust::{CheckedDir, Mistrust};

use itertools::Itertools;

use tor_error::internal;

use walkdir::WalkDir;

use tor_basic_utils::PathExt as _;

use tor_key_forge::{CertData, KeystoreItem, KeystoreItemType};

use super::KeystoreEntryResult;

/// The Arti key store.

///

/// This is a disk-based key store that encodes keys in OpenSSH format.

///

/// Some of the key types supported by the [`ArtiNativeKeystore`]

/// don't have a predefined SSH public key [algorithm name],

/// so we define several custom SSH algorithm names.

/// As per [RFC4251 § 6], our custom SSH algorithm names use the

/// `<something@subdomain.torproject.org>` format.

///

/// We have assigned the following custom algorithm names:

///   * `x25519@spec.torproject.org`, for x25519 keys

///   * `ed25519-expanded@spec.torproject.org`, for expanded ed25519 keys

///

/// See [SSH protocol extensions] for more details.

///

/// [algorithm name]: https://www.iana.org/assignments/ssh-parameters/ssh-parameters.xhtml#ssh-parameters-19

/// [RFC4251 § 6]: https://www.rfc-editor.org/rfc/rfc4251.html#section-6

/// [SSH protocol extensions]: https://spec.torproject.org/ssh-protocols.html

#[derive(Debug)]

pub struct ArtiNativeKeystore {

    /// The root of the key store.

    ///

    /// All the keys are stored within this directory.

    keystore_dir: CheckedDir,

    /// The unique identifier of this instance.

    id: KeystoreId,

}

impl ArtiNativeKeystore {

    /// Create a new [`ArtiNativeKeystore`] rooted at the specified `keystore_dir` directory.

    ///

    /// The `keystore_dir` directory is created if it doesn't exist.

    ///

    /// This function returns an error if `keystore_dir` is not a directory, if it does not conform

    /// to the requirements of the specified `Mistrust`, or if there was a problem creating the

    /// directory.

        // TODO: load the keystore ID from config.

    /// The path on disk of the key with the specified identity and type, relative to

    /// `keystore_dir`.

}

/// Extract the key path (relative to the keystore root) from the specified result `res`,

/// or return an error.

///

/// If the underlying error is `ArtiPathUnavailable` (i.e. the `KeySpecifier` cannot provide

/// an `ArtiPath`), return `ret`.

macro_rules! rel_path_if_supported {

    ($res:expr, $ret:expr) => {{

        use ArtiPathUnavailableError::*;

        match $res {

            Ok(path) => path,

            Err(ArtiPathUnavailable) => return $ret,

            Err(e) => return Err(tor_error::internal!("invalid ArtiPath: {e}").into()),

        }

    }};

}

impl Keystore for ArtiNativeKeystore {

            }

        };

        // The path exists, now check that it's actually a file and not a directory or symlink.

        } else {

        }

        };

            }

        }

        // Create the parent directories as needed

            }

            },

        };

        }

                    // Check the properties of the parent directory by attempting to list its

                    // contents.

                };

                };

                    }

                };

}

#[cfg(test)]

mod tests {

    // @@ 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_duration_subtraction)]

    #![allow(clippy::useless_vec)]

    #![allow(clippy::needless_pass_by_value)]

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

    use super::*;

    use crate::test_utils::ssh_keys::*;

    use crate::test_utils::sshkeygen_ed25519_strings;

    use crate::test_utils::TEST_SPECIFIER_PATH;

    use crate::test_utils::{assert_found, TestSpecifier};

    use crate::KeyPath;

    use std::cmp::Ordering;

    use std::fs;

    use std::path::PathBuf;

    use std::time::{Duration, SystemTime};

    use tempfile::{tempdir, TempDir};

    use tor_cert::{CertifiedKey, Ed25519Cert};

    use tor_checkable::{SelfSigned, Timebound};

    use tor_key_forge::{CertType, KeyType, ParsedEd25519Cert};

    use tor_llcrypto::pk::ed25519::{self, Ed25519PublicKey as _};

    #[cfg(unix)]

    use std::os::unix::fs::PermissionsExt;

    impl Ord for KeyPath {

        fn cmp(&self, other: &Self) -> Ordering {

            match (self, other) {

                (KeyPath::Arti(path1), KeyPath::Arti(path2)) => path1.cmp(path2),

                _ => unimplemented!("not supported"),

            }

        }

    }

    impl PartialOrd for KeyPath {

        fn partial_cmp(&self, other: &Self) -> Option<Ordering> {

            Some(self.cmp(other))

        }

    }

    fn key_path(key_store: &ArtiNativeKeystore, key_type: &KeyType) -> PathBuf {

        let rel_key_path = key_store

            .rel_path(&TestSpecifier::default(), &key_type.clone().into())

            .unwrap();

        rel_key_path.checked_path().unwrap()

    }

    fn init_keystore(gen_keys: bool) -> (ArtiNativeKeystore, TempDir) {

        let keystore_dir = tempdir().unwrap();

        #[cfg(unix)]

        fs::set_permissions(&keystore_dir, fs::Permissions::from_mode(0o700)).unwrap();

        let key_store =

            ArtiNativeKeystore::from_path_and_mistrust(&keystore_dir, &Mistrust::default())

                .unwrap();

        if gen_keys {

            let key_path = key_path(&key_store, &KeyType::Ed25519Keypair);

            let parent = key_path.parent().unwrap();

            fs::create_dir_all(parent).unwrap();

            #[cfg(unix)]

            fs::set_permissions(parent, fs::Permissions::from_mode(0o700)).unwrap();

            fs::write(key_path, ED25519_OPENSSH).unwrap();

        }

        (key_store, keystore_dir)

    }

    /// Checks if the `expected` list of `ArtiPath`s is the same as the specified `list`.

    macro_rules! assert_contains_arti_paths {

        ($expected:expr, $list:expr) => {{

            let mut expected = Vec::from_iter($expected.iter().cloned().map(KeyPath::Arti));

            expected.sort();

            let mut sorted_list = $list

                .iter()

                .filter_map(|entry| {

                    if let Ok((path, _)) = entry {

                        Some(path.clone())

                    } else {

                        None

                    }

                })

                .collect::<Vec<_>>();

            sorted_list.sort();

            assert_eq!(expected, sorted_list);

        }};

    }

    #[test]

    #[cfg(unix)]

    fn init_failure_perms() {

        use std::os::unix::fs::PermissionsExt;

        let keystore_dir = tempdir().unwrap();

        // Too permissive

        let mode = 0o777;

        fs::set_permissions(&keystore_dir, fs::Permissions::from_mode(mode)).unwrap();

        let err = ArtiNativeKeystore::from_path_and_mistrust(&keystore_dir, &Mistrust::default())

            .expect_err(&format!("expected failure (perms = {mode:o})"));

        assert_eq!(

            err.to_string(),

            format!(

                "Inaccessible path or bad permissions on {} while attempting to Init",

                keystore_dir.path().display_lossy()

            ),

            "expected keystore init failure (perms = {:o})",

            mode

        );

    }

    #[test]

    fn key_path_repr() {

        let (key_store, _) = init_keystore(false);

        assert_eq!(

            key_store

                .rel_path(&TestSpecifier::default(), &KeyType::Ed25519Keypair.into())

                .unwrap()

                .rel_path_unchecked(),

            PathBuf::from("parent1/parent2/parent3/test-specifier.ed25519_private")

        );

        assert_eq!(

            key_store

                .rel_path(

                    &TestSpecifier::default(),

                    &KeyType::X25519StaticKeypair.into()

                )

                .unwrap()

                .rel_path_unchecked(),

            PathBuf::from("parent1/parent2/parent3/test-specifier.x25519_private")

        );

    }

    #[cfg(unix)]

    #[test]

    fn get_and_rm_bad_perms() {

        use std::os::unix::fs::PermissionsExt;

        let (key_store, _keystore_dir) = init_keystore(true);

        let key_path = key_path(&key_store, &KeyType::Ed25519Keypair);

        // Make the permissions of the test key too permissive

        fs::set_permissions(&key_path, fs::Permissions::from_mode(0o777)).unwrap();

        assert!(key_store

            .get(&TestSpecifier::default(), &KeyType::Ed25519Keypair.into())

            .is_err());

        // Make the permissions of the parent directory too lax

        fs::set_permissions(

            key_path.parent().unwrap(),

            fs::Permissions::from_mode(0o777),

        )

        .unwrap();

        assert!(key_store.list().is_err());

        let key_spec = TestSpecifier::default();

        let ed_key_type = &KeyType::Ed25519Keypair.into();

        assert_eq!(

            key_store

                .remove(&key_spec, ed_key_type)

                .unwrap_err()

                .to_string(),

            format!(

                "Inaccessible path or bad permissions on {} while attempting to Remove",

                key_store

                    .rel_path(&key_spec, ed_key_type)

                    .unwrap()

                    .rel_path_unchecked()

                    .display_lossy()

            ),

        );

    }

    #[test]

    fn get() {

        // Initialize an empty key store

        let (key_store, _keystore_dir) = init_keystore(false);

        let mut expected_arti_paths = Vec::new();

        // Not found

        assert_found!(

            key_store,

            &TestSpecifier::default(),

            &KeyType::Ed25519Keypair,

            false

        );

        assert!(key_store.list().unwrap().is_empty());

        // Initialize a key store with some test keys

        let (key_store, _keystore_dir) = init_keystore(true);

        expected_arti_paths.push(TestSpecifier::default().arti_path().unwrap());

        // Found!

        assert_found!(

            key_store,

            &TestSpecifier::default(),

            &KeyType::Ed25519Keypair,

            true

        );

        assert_contains_arti_paths!(expected_arti_paths, key_store.list().unwrap());

    }

    #[test]

    fn insert() {

        // Initialize an empty key store

        let (key_store, keystore_dir) = init_keystore(false);

        let mut expected_arti_paths = Vec::new();

        // Not found

        assert_found!(

            key_store,

            &TestSpecifier::default(),

            &KeyType::Ed25519Keypair,

            false

        );

        assert!(key_store.list().unwrap().is_empty());

        let mut keys_and_specs = vec![(ED25519_OPENSSH.into(), TestSpecifier::default())];

        if let Ok((key, _)) = sshkeygen_ed25519_strings() {

            keys_and_specs.push((key, TestSpecifier::new("-sshkeygen")));

        }

        for (i, (key, key_spec)) in keys_and_specs.iter().enumerate() {

            // Insert the keys

            let key = UnparsedOpenSshKey::new(key.into(), PathBuf::from("/test/path"));

            let erased_kp = key

                .parse_ssh_format_erased(&KeyType::Ed25519Keypair)

                .unwrap();

            let Ok(key) = erased_kp.downcast::<ed25519::Keypair>() else {

                panic!("failed to downcast key to ed25519::Keypair")

            };

            let path = keystore_dir.as_ref().join(

                key_store

                    .rel_path(key_spec, &KeyType::Ed25519Keypair.into())

                    .unwrap()

                    .rel_path_unchecked(),

            );

            // The key and its parent directories don't exist for first key.

            // They are created after the first key is inserted.

            assert_eq!(!path.parent().unwrap().try_exists().unwrap(), i == 0);

            assert!(key_store.insert(&*key, key_spec).is_ok());

            // Update expected_arti_paths after inserting key

            expected_arti_paths.push(key_spec.arti_path().unwrap());

            // insert() is supposed to create the missing directories

            assert!(path.parent().unwrap().try_exists().unwrap());

            // Found!

            assert_found!(key_store, key_spec, &KeyType::Ed25519Keypair, true);

            // Check keystore list

            assert_contains_arti_paths!(expected_arti_paths, key_store.list().unwrap());

        }

    }

    #[test]

    fn remove() {

        // Initialize the key store

        let (key_store, _keystore_dir) = init_keystore(true);

        let mut expected_arti_paths = vec![TestSpecifier::default().arti_path().unwrap()];

        let mut specs = vec![TestSpecifier::default()];

        assert_found!(

            key_store,

            &TestSpecifier::default(),

            &KeyType::Ed25519Keypair,

            true

        );

        if let Ok((key, _)) = sshkeygen_ed25519_strings() {

            // Insert ssh-keygen key

            let key = UnparsedOpenSshKey::new(key, PathBuf::from("/test/path"));

            let erased_kp = key

                .parse_ssh_format_erased(&KeyType::Ed25519Keypair)

                .unwrap();

            let Ok(key) = erased_kp.downcast::<ed25519::Keypair>() else {

                panic!("failed to downcast key to ed25519::Keypair")

            };

            let key_spec = TestSpecifier::new("-sshkeygen");

            assert!(key_store.insert(&*key, &key_spec).is_ok());

            expected_arti_paths.push(key_spec.arti_path().unwrap());

            specs.push(key_spec);

        }

        let ed_key_type = &KeyType::Ed25519Keypair.into();

        for spec in specs {

            // Found!

            assert_found!(key_store, &spec, &KeyType::Ed25519Keypair, true);

            // Check keystore list before removing key

            assert_contains_arti_paths!(expected_arti_paths, key_store.list().unwrap());

            // Now remove the key... remove() should indicate success by returning Ok(Some(()))

            assert_eq!(key_store.remove(&spec, ed_key_type).unwrap(), Some(()));

            // Remove the current key_spec's ArtiPath from expected_arti_paths

            expected_arti_paths.retain(|arti_path| *arti_path != spec.arti_path().unwrap());

            // Can't find it anymore!

            assert_found!(key_store, &spec, &KeyType::Ed25519Keypair, false);

            // Check keystore list after removing key

            assert_contains_arti_paths!(expected_arti_paths, key_store.list().unwrap());

            // remove() returns Ok(None) now.

            assert!(key_store.remove(&spec, ed_key_type).unwrap().is_none());

        }

        assert!(key_store.list().unwrap().is_empty());

    }

    #[test]

    fn list() {

        // Initialize the key store

        let (key_store, keystore_dir) = init_keystore(true);

        let mut expected_arti_paths = vec![TestSpecifier::default().arti_path().unwrap()];

        assert_contains_arti_paths!(expected_arti_paths, key_store.list().unwrap());

        let mut keys_and_specs =

            vec![(ED25519_OPENSSH.into(), TestSpecifier::new("-i-am-a-suffix"))];

        if let Ok((key, _)) = sshkeygen_ed25519_strings() {

            keys_and_specs.push((key, TestSpecifier::new("-sshkeygen")));

        }

        // Insert more keys

        for (key, key_spec) in keys_and_specs {

            let key = UnparsedOpenSshKey::new(key, PathBuf::from("/test/path"));

            let erased_kp = key

                .parse_ssh_format_erased(&KeyType::Ed25519Keypair)

                .unwrap();

            let Ok(key) = erased_kp.downcast::<ed25519::Keypair>() else {

                panic!("failed to downcast key to ed25519::Keypair")

            };

            assert!(key_store.insert(&*key, &key_spec).is_ok());

            expected_arti_paths.push(key_spec.arti_path().unwrap());

            assert_contains_arti_paths!(expected_arti_paths, key_store.list().unwrap());

        }

        // Insert key with invalid ArtiPath

        let _ = fs::File::create(keystore_dir.path().join(TEST_SPECIFIER_PATH)).unwrap();

        let entries = key_store.list().unwrap();

        let mut unrecognized_entries = entries.iter().filter_map(|e| {

            let Err(entry) = e else {

                return None;

            };

            #[allow(irrefutable_let_patterns)]

            let UnrecognizedEntryId::Path(path) = entry.entry() else {

                return None;

            };

            Some(path)

        });

        assert_eq!(

            unrecognized_entries.next().unwrap(),

            Path::new(TEST_SPECIFIER_PATH)

        );

        assert!(unrecognized_entries.next().is_none());

    }

    #[test]

    fn key_path_not_regular_file() {

        let (key_store, _keystore_dir) = init_keystore(false);

        let key_path = key_path(&key_store, &KeyType::Ed25519Keypair);

        // The key is a directory, not a regular file

        fs::create_dir_all(&key_path).unwrap();

        assert!(key_path.try_exists().unwrap());

        let parent = key_path.parent().unwrap();

        #[cfg(unix)]

        fs::set_permissions(parent, fs::Permissions::from_mode(0o700)).unwrap();

        let err = key_store

            .contains(&TestSpecifier::default(), &KeyType::Ed25519Keypair.into())

            .unwrap_err();

        assert!(err.to_string().contains("not a regular file"), "{err}");

    }

    #[test]

    fn certs() {

        let (key_store, _keystore_dir) = init_keystore(false);

        let mut rng = rand::rng();

        let subject_key = ed25519::Keypair::generate(&mut rng);

        let signing_key = ed25519::Keypair::generate(&mut rng);

        // Note: the cert constructor rounds the expiration forward to the nearest hour

        // after the epoch.

        let cert_exp = SystemTime::UNIX_EPOCH + Duration::from_secs(60 * 60);

        let encoded_cert = Ed25519Cert::constructor()

            .cert_type(tor_cert::CertType::IDENTITY_V_SIGNING)

            .expiration(cert_exp)

            .signing_key(signing_key.public_key().into())

            .cert_key(CertifiedKey::Ed25519(subject_key.public_key().into()))

            .encode_and_sign(&signing_key)

            .unwrap();

        // The specifier doesn't really matter.

        let cert_spec = TestSpecifier::default();

        assert!(key_store.insert(&encoded_cert, &cert_spec).is_ok());

        let erased_cert = key_store

            .get(&cert_spec, &CertType::Ed25519TorCert.into())

            .unwrap()

            .unwrap();

        let Ok(found_cert) = erased_cert.downcast::<ParsedEd25519Cert>() else {

            panic!("failed to downcast cert to KewUnknownCert")

        };

        let found_cert = found_cert

            .should_be_signed_with(&signing_key.public_key().into())

            .unwrap()

            .dangerously_assume_wellsigned()

            .dangerously_assume_timely();

        assert_eq!(

            found_cert.as_ref().cert_type(),

            tor_cert::CertType::IDENTITY_V_SIGNING

        );

        assert_eq!(found_cert.as_ref().expiry(), cert_exp);

        assert_eq!(

            found_cert.as_ref().signing_key(),

            Some(&signing_key.public_key().into())

        );

        assert_eq!(

            found_cert.subject_key().unwrap(),

            &subject_key.public_key().into()

        );

    }

}