gel-dsn 0.2.16

use std::{
    collections::{HashMap, HashSet},
    fmt::Debug,
    num::NonZeroU16,
    path::{Path, PathBuf},
    time::Duration,
};

use rustls_pki_types::CertificateDer;
use url::Url;

use super::{
    env::Env,
    error::*,
    project::{find_project_file, ProjectDir},
    stored::{StoredCredentials, StoredInformation},
    BuildContext, BuildContextImpl, ClientSecurity, CloudCerts, CloudCredentialsFile, Config,
    CredentialsFile, DatabaseBranch, FromParamStr, InstanceName, Logging, Param, ParamSource,
    TcpKeepalive, TlsSecurity, UnixPath, DEFAULT_CONNECT_TIMEOUT, DEFAULT_PORT, DEFAULT_WAIT,
};
use crate::{
    env::SystemEnvVars,
    file::SystemFileAccess,
    gel::{context_trace, Authentication, DEFAULT_USER},
    host::{Host, HostType},
    user::SystemUserProfile,
    EnvVar, FileAccess, UserProfile,
};

#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, derive_more::Display)]
pub enum BuildPhase {
    #[display("command-line or driver options")]
    Options,
    #[display("environment variables")]
    Environment,
    #[display("project directory")]
    Project,
}

/// A builder for [`Config`].
#[derive(Debug, Clone, Default)]
pub struct Builder {
    params: Params,
}

macro_rules! define_params {
    ($(
        $(#[doc = $doc:expr])* $name:ident: $type:ty
    ),* $(,)?) => {
        /// The parameters used to build the [`Config`].
        #[derive(Clone, Default, PartialEq, Eq)]
        #[non_exhaustive]
        pub struct Params {
            $(
                $(#[doc = $doc])*
                pub $name: Param<$type>,
            )*

            pub server_settings: HashMap<String, String>,
        }

        impl Debug for Params {
            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
                let mut s = f.debug_struct("Params");
                $(
                    if self.$name.is_some() {
                        s.field(stringify!($name), &self.$name);
                    }
                )*
                s.finish()
            }
        }

        impl Params {
            pub fn merge(&mut self, mut other: Self) {
                // Special case: database/branch cannot be set if the other is
                // already set.
                if self.database.is_none() && self.branch.is_some() {
                    other.database = Param::None;
                }
                if self.branch.is_none() && self.database.is_some() {
                    other.branch = Param::None;
                }

                $(
                    if self.$name.is_none() {
                        self.$name = other.$name;
                    }
                )*


                for (key, value) in other.server_settings {
                    self.server_settings.entry(key).or_insert(value);
                }
            }

            /// Compute the parameters.
            fn into_computed(self, context: &impl BuildContext) -> (Computed, Vec<ParseError>) {
                let mut errors = Vec::new();
                let computed = Computed {
                    $(
                        $name: self.$name.get(context).unwrap_or_else(|e| {
                            errors.push(e);
                            None
                        }),
                    )*

                    server_settings: self.server_settings.clone(),
                };
                (computed, errors)
            }
        }

        /// The parameters used to build the [`Config`].
        #[derive(Clone, Default)]
        #[cfg(feature = "unstable")]
        pub struct Computed {
            $(
                $(#[doc = $doc])*
                pub $name: Option<$type>,
            )*

            pub server_settings: HashMap<String, String>,
        }

        /// The parameters used to build the [`Config`].
        #[derive(Clone, Default)]
        #[cfg(not(feature = "unstable"))]
        pub(crate) struct Computed {
            $(
                $(#[doc = $doc])*
                pub $name: Option<$type>,
            )*

            pub server_settings: HashMap<String, String>,
        }

        impl Debug for Computed {
            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
                let mut s = f.debug_struct("Computed");
                $(
                    if let Some(value) = &self.$name {
                        s.field(stringify!($name), &value);
                    }
                )*
                s.finish()
            }
        }

        impl Builder {
            $(
                // Note that paste! forces re-interpretation of type token and allows us
                // to match the __maybe__* macros below.
                paste::paste!{
                    define_params!{__maybe_into__ $(#[doc = $doc])* $name: $type}

                    $(#[doc = $doc])*
                    #[doc = "\n\nThis value will be loaded from `path` in the filesystem and parsed as [`"]
                    #[doc = stringify!($type)]
                    #[doc = "`]."]
                    pub fn [<$name _file>](mut self, path: impl AsRef<Path>) -> Self {
                        self.params.$name = Param::File(path.as_ref().to_path_buf());
                        self
                    }

                    $(#[doc = $doc])*
                    #[doc = "\n\nWill be loaded from the provided environment variable and parsed as [`"]
                    #[doc = stringify!($type)]
                    #[doc = "`]."]
                    pub fn [<$name _env>](mut self, value: impl AsRef<str>) -> Self {
                        self.params.$name = Param::Env(ParamSource::Explicit, value.as_ref().to_string());
                        self
                    }

                    define_params!{__maybe_string__ $(#[doc = $doc])* $name: $type}
                }
            )*
        }
    };
    // NOTE: Special case u16 since number literals don't cooperate well with
    // type inference + Into.
    (__maybe_into__ $(#[doc = $doc:expr])* $name:ident: u16) => {
        $(#[doc = $doc])*
        pub fn $name(mut self, value: u16) -> Self {
            self.params.$name = Param::Parsed(value);
            self
        }
    };
    (__maybe_into__ $(#[doc = $doc:expr])* $name:ident: $type:ty) => {
        $(#[doc = $doc])*
        pub fn $name(mut self, value: impl Into<$type>) -> Self {
            self.params.$name = Param::Parsed(value.into());
            self
        }
    };
    (__maybe_string__ $(#[doc = $doc:expr])* $name:ident: String) => {
    };
    (__maybe_string__ $(#[doc = $doc:expr])* $name:ident: $type:ty) => {
        paste::paste!(
            $(#[doc = $doc])*
            #[doc = "\n\nWill be loaded from the provided string and parsed as [`"]
            #[doc = stringify!($type)]
            #[doc = "`]."]
            pub fn [<$name _string>](mut self, value: impl AsRef<str>) -> Self {
                self.params.$name = Param::Unparsed(value.as_ref().to_string());
                self
            }
        );
    };
}

define_params!(
    /// The datasource name URL. Valid URLs must start with `edgedb://` or `gel://`.
    dsn: String,
    /// The instance.
    instance: InstanceName,
    /// The credentials. Note that [`CredentialsFile`] is considered an opaque
    /// type that can only be created from a string (see [`std::str::FromStr`])
    /// or deserialized from a file (see [`Builder::credentials_file`]).
    credentials: CredentialsFile,
    /// The host. Note that [`HostType`] is considered an opaque type that can
    /// only be created from a string (see [`std::str::FromStr`]) or from
    /// [`std::net::Ipv4Addr`], [`std::net::Ipv6Addr`], or [`std::net::IpAddr`].
    ///
    /// ```rust
    /// # use gel_dsn::{HostType, gel::Builder};
    /// # use std::net::*;
    /// # use std::str::FromStr;
    /// # let builder = Builder::new();
    /// builder.host(HostType::from_str("localhost").unwrap());
    /// # let builder = Builder::new();
    /// builder.host(Ipv4Addr::new(127, 0, 0, 1));
    /// ```
    host: HostType,
    /// The port.
    port: u16,
    /// The unix socket path.
    unix_path: UnixPath,
    /// The database name. Used for EdgeDB < 5. For Gel or EdgeDB >= 5, use
    /// [`Builder::branch`].
    database: String,
    /// The branch name. Used for Gel or EdgeDB >= 5.
    branch: String,
    /// The username.
    user: String,
    /// The password.
    ///
    /// If set, the client will use SCRAM to authenticate with the server, if
    /// the server requests it.
    password: String,
    /// The client security mode. Setting this to [`ClientSecurity::InsecureDevMode`]
    /// will disable security checks unless they have been explicitly enabled.
    client_security: ClientSecurity,
    /// The TLS CA used to verify the server certificate.
    tls_ca: Vec<CertificateDer<'static>>,
    /// The TLS security mode.
    ///
    /// When set to [`TlsSecurity::Default`], the certificate chain is always
    /// verified to come from a root of trust. If a specific certificate is
    /// provided, hostname verification is disabled.
    ///
    /// See [`TlsSecurity`] for more details.
    tls_security: TlsSecurity,
    /// The TLS Server Name Indication to send.
    ///
    /// Overrides the default Server Name Indication (SNI) sent by the TLS
    /// library. In most cases this is not required to be set, but some load
    /// balancers or multi-tenant setups may require this setting to ensure the
    /// connection is correctly routed.
    tls_server_name: String,
    /// The secret key.
    ///
    /// Used for JWT authentication. When set, the client will send the token as
    /// part of the server handshake.
    secret_key: String,
    /// The cloud profile.
    cloud_profile: String,
    /// How long to wait for the server to be available.
    ///
    /// This works by ignoring certain errors known to happen while the database
    /// is starting up or restarting (e.g. "connection refused" or early
    /// "connection reset").
    ///
    /// Note: the amount of time establishing a connection can take is the sum
    /// of `wait_until_available` plus `connect_timeout`
    wait_until_available: Duration,
    /// The cloud certificates to use.
    cloud_certs: CloudCerts,
    /// The TCP keepalive.
    ///
    /// Sets the TCP keepalive interval and time for the database connection to
    /// ensure that the remote end of the connection is still alive, and to
    /// inform any network intermediaries that this connection is not idle. By
    /// default, a keepalive probe will be sent once every 60 seconds once the
    /// connection has been idle for 60 seconds.
    ///
    /// Note: If the connection is not made over a TCP socket, this value will
    /// be unused. If the current platform does not support explicit TCP
    /// keep-alive intervals on the socket, keepalives will be enabled and the
    /// operating-system default for the intervals will be used.
    tcp_keepalive: TcpKeepalive,
    /// The maximum number of concurrent connections.
    max_concurrency: usize,
    /// The connection timeout.
    ///
    /// The default is 10 seconds. A subsecond timeout should be fine for most
    /// networks. However, in some cases this can be much slower. That's because
    /// this timeout includes authentication, during which:
    /// * The password is checked (slow by design).
    /// * A compiler process is launched (slow now, may be optimized later).
    ///
    /// So in a concurrent case on slower VMs (such as CI with parallel tests),
    /// 10 seconds is more reasonable default.
    ///
    /// The `wait_until_available` setting should be larger than this value to
    /// allow multiple attempts.
    ///
    /// Note: the amount of time establishing a connection can take is the sum
    /// of `wait_until_available` plus `connect_timeout`
    connect_timeout: Duration,
);

impl Computed {
    pub fn is_complete(&self) -> bool {
        self.host.is_some() || self.port.is_some() || self.credentials.is_some()
    }
}

impl Builder {
    /// Create a new builder with default parameters.
    pub fn new() -> Self {
        Self::default()
    }

    /// Create a new builder from something that can be converted into a [`Params`] object.
    pub fn new_from(
        params: impl TryInto<Params, Error = ParseError>,
    ) -> Result<Self, gel_errors::Error> {
        let params = params.try_into().map_err(|e| e.gel_error())?;
        Ok(Self { params })
    }

    /// Merge the given parameters into this builder.
    pub fn params(mut self, params: impl Into<Params>) -> Self {
        self.params.merge(params.into());
        self
    }

    /// Merge the given parameters into this builder.
    pub fn try_params<E>(mut self, params: impl TryInto<Params, Error = E>) -> Result<Self, E> {
        self.params.merge(params.try_into()?);
        Ok(self)
    }

    /// Set the allowed certificate as a PEM file.
    #[deprecated(note = "Use `tls_ca` instead")]
    pub fn pem_certificates(mut self, cert_data: &str) -> Result<Self, gel_errors::Error> {
        self.params.tls_ca = Param::Unparsed(cert_data.to_string());
        Ok(self)
    }

    /// Build the [`Config`] from the parameters and the local system
    /// environment, including environment variables and credentials assumed
    /// from the current working directory.
    ///
    /// NOTE: This method is not actually `async` but maintains the `async`
    /// signature for compatibility.
    #[deprecated(note = "Use `build` instead")]
    pub async fn build_env(self) -> Result<Config, gel_errors::Error> {
        self.with_system().build()
    }

    /// Prepare the builder for building the config without any system access
    /// configured. `with_env` and `with_fs` can be used to add system access.
    #[allow(deprecated, private_interfaces)]
    pub fn without_system(
        self,
    ) -> BuilderPrepare<WithoutEnv, WithoutFs, WithoutUser, WithoutProject> {
        BuilderPrepare {
            params: self.params,
            project_dir: None,
            env: Default::default(),
            fs: Default::default(),
            user: Default::default(),
            logging: Default::default(),
            _phantom: std::marker::PhantomData,
        }
    }

    #[doc(hidden)]
    #[allow(deprecated, private_interfaces)]
    pub fn with_system_impl<S: EnvVar + FileAccess + UserProfile + Clone>(
        self,
        system: S,
    ) -> BuilderPrepare<WithEnv<S>, WithFs<S>, WithUser<S>, WithoutProject> {
        self.without_system()
            .set_env(system.clone())
            .set_fs(system.clone())
            .set_user(system)
    }

    /// Prepare the builder for building the config with system access
    /// configured. This is equivalent to calling
    /// `without_system().with_env().with_fs().with_auto_project_cwd()`.
    #[allow(deprecated, private_interfaces)]
    pub fn with_system(
        self,
    ) -> BuilderPrepare<
        WithEnv<SystemEnvVars>,
        WithFs<SystemFileAccess>,
        WithUser<SystemUserProfile>,
        WithProject,
    > {
        self.without_system()
            .with_env()
            .with_fs()
            .with_auto_project_cwd()
    }

    /// Prepare the builder for building the config with environment variables
    /// configured.
    #[allow(deprecated, private_interfaces)]
    pub fn with_env(
        self,
    ) -> BuilderPrepare<WithEnv<SystemEnvVars>, WithoutFs, WithoutUser, WithoutProject> {
        self.without_system().with_env()
    }

    /// Prepare the builder for building the config with file system access
    /// configured.
    #[allow(deprecated, private_interfaces)]
    pub fn with_fs(
        self,
    ) -> BuilderPrepare<
        WithoutEnv,
        WithFs<SystemFileAccess>,
        WithUser<SystemUserProfile>,
        WithoutProject,
    > {
        self.without_system().with_fs()
    }

    /// Build the [`Config`] from the parameters and the local system
    /// environment, including environment variables and credentials assumed
    /// from the current working directory.
    pub fn build(self) -> Result<Config, gel_errors::Error> {
        self.with_system().build()
    }

    /// Build the [`Computed`] parameters from the parameters and the local
    /// system environment, including environment variables and credentials
    /// assumed from the current working directory.
    #[cfg(feature = "unstable")]
    pub fn compute(self) -> Result<(Computed, Vec<ParseError>), ParseError> {
        self.with_system().compute()
    }

    /// Read and write stored credentials and project information.
    #[cfg(feature = "unstable")]
    #[allow(private_interfaces)]
    pub fn stored_info(self) -> StoredInformation<impl BuildContext> {
        self.with_system().stored_info()
    }
}

#[doc(hidden)]
pub struct WithEnv<E: EnvVar>(std::marker::PhantomData<E>);
#[doc(hidden)]
pub struct WithoutEnv;
#[doc(hidden)]
pub struct WithFs<F: FileAccess>(std::marker::PhantomData<F>);
#[doc(hidden)]
pub struct WithoutFs;
#[doc(hidden)]
pub struct WithUser<U: UserProfile>(std::marker::PhantomData<U>);
#[doc(hidden)]
pub struct WithoutUser;
#[doc(hidden)]
pub struct WithProject;
#[doc(hidden)]
pub struct WithoutProject;

trait BuilderEnv: Sized {
    type Env: EnvVar;
}
trait BuilderFs: Sized {
    type File: FileAccess;
}
trait BuilderUser: Sized {
    type UserProfile: UserProfile;
}
trait BuilderProject: Sized {}

impl<E: EnvVar> BuilderEnv for WithEnv<E> {
    type Env = E;
}
impl BuilderEnv for WithoutEnv {
    type Env = ();
}
impl<F: FileAccess> BuilderFs for WithFs<F> {
    type File = F;
}
impl BuilderFs for WithoutFs {
    type File = ();
}
impl<U: UserProfile> BuilderUser for WithUser<U> {
    type UserProfile = U;
}
impl BuilderUser for WithoutUser {
    type UserProfile = ();
}
impl BuilderProject for WithProject {}
impl BuilderProject for WithoutProject {}

/// An internal type used to prepare a [`Builder`] for building a [`Config`].
///
/// This type is considered an implementation detail and should not be named
/// directly.
#[allow(deprecated, private_bounds)]
pub struct BuilderPrepare<E: BuilderEnv, F: BuilderFs, U: BuilderUser, P: BuilderProject> {
    params: Params,
    project_dir: Option<ProjectDir>,
    env: E::Env,
    fs: F::File,
    user: U::UserProfile,
    logging: Logging,
    _phantom: std::marker::PhantomData<(E, F, P)>,
}

#[allow(deprecated, private_bounds)]
impl<E: BuilderEnv, F: BuilderFs, U: BuilderUser, P: BuilderProject> BuilderPrepare<E, F, U, P> {
    #[doc(hidden)]
    #[allow(deprecated, private_interfaces)]
    fn set_env<NEW: EnvVar>(self, env: NEW) -> BuilderPrepare<WithEnv<NEW>, F, U, P> {
        BuilderPrepare {
            params: self.params,
            project_dir: self.project_dir,
            env,
            fs: self.fs,
            user: self.user,
            logging: self.logging,
            _phantom: std::marker::PhantomData,
        }
    }

    #[doc(hidden)]
    #[allow(deprecated, private_interfaces)]
    fn set_fs<NEW: FileAccess>(self, fs: NEW) -> BuilderPrepare<E, WithFs<NEW>, U, P> {
        BuilderPrepare {
            params: self.params,
            project_dir: self.project_dir,
            env: self.env,
            fs,
            user: self.user,
            logging: self.logging,
            _phantom: std::marker::PhantomData,
        }
    }

    #[doc(hidden)]
    #[allow(deprecated, private_interfaces)]
    fn set_user<NEW: UserProfile>(self, user: NEW) -> BuilderPrepare<E, F, WithUser<NEW>, P> {
        BuilderPrepare {
            params: self.params,
            project_dir: self.project_dir,
            env: self.env,
            fs: self.fs,
            user,
            logging: self.logging,
            _phantom: std::marker::PhantomData,
        }
    }

    #[doc(hidden)]
    #[allow(deprecated, private_interfaces)]
    fn set_project_dir(
        self,
        project_dir: Option<ProjectDir>,
    ) -> BuilderPrepare<E, F, U, WithProject> {
        BuilderPrepare {
            params: self.params,
            project_dir,
            env: self.env,
            fs: self.fs,
            user: self.user,
            logging: self.logging,
            _phantom: std::marker::PhantomData,
        }
    }

    #[doc(hidden)]
    pub fn with_env_impl<NEW: EnvVar>(self, env: NEW) -> BuilderPrepare<WithEnv<NEW>, F, U, P> {
        self.set_env(env)
    }

    #[doc(hidden)]
    pub fn with_fs_impl<NEW: FileAccess>(self, fs: NEW) -> BuilderPrepare<E, WithFs<NEW>, U, P> {
        self.set_fs(fs)
    }

    #[doc(hidden)]
    pub fn with_user_impl<NEW: UserProfile>(
        self,
        user: NEW,
    ) -> BuilderPrepare<E, F, WithUser<NEW>, P> {
        self.set_user(user)
    }

    /// Enable tracing of the build process.
    pub fn with_tracing(mut self, f: impl Fn(&str) + 'static) -> BuilderPrepare<E, F, U, P> {
        self.logging.tracing = Some(Box::new(f));
        self
    }

    pub fn with_warning(mut self, f: impl Fn(Warning) + 'static) -> BuilderPrepare<E, F, U, P> {
        self.logging.warning = Some(Box::new(f));
        self
    }

    /// Enable logging for build warnings and traces.
    #[cfg(feature = "log")]
    pub fn with_logging(mut self) -> BuilderPrepare<E, F, U, P> {
        self.logging.log_warning = true;
        self.logging.log_trace = true;
        self
    }
}

#[allow(deprecated, private_bounds)]
impl<E: BuilderEnv, F: FileAccess, U: UserProfile, P: BuilderProject>
    BuilderPrepare<E, WithFs<F>, WithUser<U>, P>
{
    /// Configure the project directory based on the current working directory.
    /// If sufficient information is found is found in the initial
    /// configuration, the project will not be loaded.
    #[allow(deprecated)]
    pub fn with_auto_project_cwd(self) -> BuilderPrepare<E, WithFs<F>, WithUser<U>, WithProject> {
        self.set_project_dir(Some(ProjectDir::SearchCwd))
    }

    /// Configure the project directory to be the given directory. If no project
    /// is found, it is silently ignored. If sufficient information is found is found
    /// in the initial configuration, the project will not be loaded.
    #[allow(deprecated)]
    pub fn with_auto_project(
        self,
        project_dir: impl AsRef<Path>,
    ) -> BuilderPrepare<E, WithFs<F>, WithUser<U>, WithProject> {
        self.set_project_dir(Some(ProjectDir::Search(project_dir.as_ref().to_path_buf())))
    }

    /// Configure the project directory to be the given directory. Does not
    /// perform a search for project files. If sufficient information is found
    /// is found in the initial configuration, the project will not be loaded.
    #[allow(deprecated)]
    pub fn with_explicit_project(
        self,
        project_dir: impl AsRef<Path>,
    ) -> BuilderPrepare<E, WithFs<F>, WithUser<U>, WithProject> {
        self.set_project_dir(Some(ProjectDir::NoSearch(
            project_dir.as_ref().to_path_buf(),
        )))
    }
}

#[allow(deprecated, private_bounds)]
impl<F: BuilderFs, U: BuilderUser, P: BuilderProject> BuilderPrepare<WithoutEnv, F, U, P> {
    /// Configure the builder to use the environment for configuration.
    #[allow(deprecated)]
    pub fn with_env(self) -> BuilderPrepare<WithEnv<SystemEnvVars>, F, U, P> {
        self.set_env(SystemEnvVars)
    }
}

#[allow(deprecated, private_bounds)]
impl<E: BuilderEnv, P: BuilderProject> BuilderPrepare<E, WithoutFs, WithoutUser, P> {
    /// Configure the builder to use the file system for configuration.
    #[allow(deprecated)]
    pub fn with_fs(
        self,
    ) -> BuilderPrepare<E, WithFs<SystemFileAccess>, WithUser<SystemUserProfile>, P> {
        self.set_fs(SystemFileAccess).set_user(SystemUserProfile)
    }
}

#[allow(deprecated, private_bounds)]
impl<E: BuilderEnv, F: BuilderFs, U: BuilderUser, P: BuilderProject> BuilderPrepare<E, F, U, P> {
    /// Build the [`Config`] from the parameters, with optional environment,
    /// file system access, and project directory potentially configured.
    pub fn build(self) -> Result<Config, gel_errors::Error> {
        self.build_parse_error().map_err(|e| e.gel_error())
    }

    /// Build the [`Computed`] parameters from the parameters, with optional
    /// environment, file system access, and project directory potentially configured.
    ///
    /// This is a best-effort attempt to make sense of the provided options.
    #[cfg(feature = "unstable")]
    pub fn compute(self) -> Result<(Computed, Vec<ParseError>), ParseError> {
        let params = self.params;

        let mut context = BuildContextImpl::new_with_user_profile(self.env, self.fs, self.user);
        context.logging = self.logging;
        compute(params, &context, self.project_dir)
    }

    /// Read and write stored credentials and project information.
    #[cfg(feature = "unstable")]
    #[allow(private_interfaces)]
    pub fn stored_info(self) -> StoredInformation<impl BuildContext> {
        let mut context = BuildContextImpl::new_with_user_profile(self.env, self.fs, self.user);
        context.logging = self.logging;
        StoredInformation::new(context)
    }

    #[doc(hidden)]
    pub fn build_parse_error(self) -> Result<Config, ParseError> {
        let params = self.params;

        let mut context = BuildContextImpl::new_with_user_profile(self.env, self.fs, self.user);
        context.logging = self.logging;
        parse(params, &context, self.project_dir)
    }
}

impl Params {
    fn check_overlap(&self) -> Vec<CompoundSource> {
        let mut sources = Vec::new();
        if self.dsn.is_some() {
            sources.push(CompoundSource::Dsn);
        }
        if self.instance.is_some() && self.unix_path.is_none() {
            sources.push(CompoundSource::Instance);
        }
        if self.unix_path.is_some() {
            sources.push(CompoundSource::UnixSocket);
            if self.host.is_some() {
                sources.push(CompoundSource::HostPort);
            }
        } else if self.host.is_some() || self.port.is_some() {
            sources.push(CompoundSource::HostPort);
        }
        if self.credentials.is_some() {
            sources.push(CompoundSource::CredentialsFile);
        }
        sources
    }

    pub(crate) fn try_compute(
        &self,
        context: &impl BuildContext,
        phase: BuildPhase,
    ) -> Result<(Computed, Vec<ParseError>), ParseError> {
        // Step 0: Check for compound option overlap. If there is, return an error.
        let compound_sources = self.check_overlap();
        if compound_sources.len() > 1 {
            return Err(ParseError::MultipleCompound(phase, compound_sources));
        }

        // Step 1: Resolve DSN, credentials file, instance if available
        let mut explicit = self.clone();

        context_trace!(context, "Start: {:?}", explicit);

        // Take and compute the compound options first since they may have
        // special handling.
        let dsn = explicit.dsn.take().get(context);
        let instance = explicit.instance.take().get(context);
        let credentials = explicit.credentials.take().get(context);

        let dsn = dsn?;
        if let Some(dsn) = &dsn {
            let res = parse_dsn(dsn, context);
            if let Err(e) = &res {
                context_trace!(context, "DSN error: {:?}", e);
            }
            let dsn = res?;
            context_trace!(context, "DSN: {:?}", dsn);
            explicit.merge(dsn);
        }

        let credentials = credentials.map_err(|e| {
            // Special case: map FileNotFound to InvalidCredentialsFile
            if e == ParseError::FileNotFound {
                ParseError::InvalidCredentialsFile(InvalidCredentialsFileError::FileNotFound)
            } else {
                e
            }
        })?;
        if let Some(file) = &credentials {
            let file = parse_credentials(file, context)?;
            context_trace!(context, "Credentials: {:?}", file);
            explicit.merge(file);
        }

        let instance = instance?;
        if let Some(instance) = &instance {
            match &instance {
                InstanceName::Local(local) => {
                    let instance = parse_instance(local, context)?;
                    context_trace!(context, "Instance: {:?}", instance);
                    explicit.merge(instance);
                }
                InstanceName::Cloud { .. } => {
                    let profile = explicit
                        .cloud_profile
                        .get(context)?
                        .unwrap_or("default".to_string());
                    let cloud = parse_cloud(&profile, context)?;
                    context_trace!(context, "Cloud: {:?}", cloud);
                    explicit.merge(cloud);

                    if let Some(secret_key) = explicit.secret_key.get(context)? {
                        match instance.cloud_address(&secret_key) {
                            Ok(Some(address)) => {
                                explicit.host = Param::Unparsed(address);
                            }
                            Ok(None) => {
                                unreachable!();
                            }
                            Err(e) => {
                                // Special case: we ignore the secret key error until the final phase
                                if phase == BuildPhase::Project {
                                    return Err(e);
                                }
                            }
                        }
                    } else {
                        // Special case: we ignore the secret key error until the final phase
                        if phase == BuildPhase::Project {
                            return Err(ParseError::SecretKeyNotFound);
                        }
                    }
                }
            }
        }

        context_trace!(context, "Merged: {:?}", explicit);

        let (mut computed, errors) = explicit.into_computed(context);
        computed.instance = instance;
        computed.dsn = dsn;
        computed.credentials = credentials;

        Ok((computed, errors))
    }

    /// Try to build the config. Returns `None` if the config is incomplete.
    pub(crate) fn try_build(
        &self,
        context: &impl BuildContext,
        phase: BuildPhase,
    ) -> Result<Option<Config>, ParseError> {
        let (computed, errors) = self.try_compute(context, phase)?;
        if !errors.is_empty() {
            return Err(errors.into_iter().next().unwrap());
        }

        context_trace!(context, "Computed: {:?}", computed);

        // Step 2: Resolve host. If we have no host yet, exit.
        let port = computed.port;
        if port == Some(0) {
            return Err(ParseError::InvalidPort);
        }

        let host = if let Some(unix_path) = computed.unix_path {
            let path = unix_path
                .path_with_port(port.unwrap_or(DEFAULT_PORT))
                .into_owned();
            Host::new(HostType::from_unix_path(path), DEFAULT_PORT)
        } else {
            let host = match (computed.host, port) {
                (Some(host), Some(port)) => Host::new(host, port),
                (Some(host), None) => Host::new(host, DEFAULT_PORT),
                (None, Some(port)) => Host::new(HostType::try_from_str("localhost").unwrap(), port),
                (None, None) => {
                    return Ok(None);
                }
            };

            // Only allow the unix socket if it's explicitly set through unix_path
            if host.is_unix() {
                return Err(ParseError::UnixSocketUnsupported);
            }

            host
        };

        let authentication = if let Some(password) = computed.password {
            Authentication::Password(password)
        } else if let Some(secret_key) = computed.secret_key {
            Authentication::SecretKey(secret_key)
        } else {
            Authentication::None
        };

        let user = computed.user;
        let database = computed.database;
        let branch = computed.branch;

        for (param, error) in [
            (&user, ParseError::InvalidUser),
            (&database, ParseError::InvalidDatabase),
            (&branch, ParseError::InvalidDatabase),
        ] {
            if let Some(param) = param {
                if param.trim() != param || param.is_empty() {
                    return Err(error);
                }
            }
        }

        let db = match (database, branch) {
            (Some(db), Some(branch)) if db != branch => {
                return Err(ParseError::InvalidDatabase);
            }
            (Some(_), Some(branch)) => DatabaseBranch::Ambiguous(branch),
            (Some(db), None) => DatabaseBranch::Database(db),
            (None, Some(branch)) => DatabaseBranch::Branch(branch),
            (None, None) => DatabaseBranch::Default,
        };

        let tls_ca = computed.tls_ca;

        let client_security = computed.client_security.unwrap_or_default();
        let tls_security = computed.tls_security.unwrap_or_default();
        let tls_server_name = computed.tls_server_name;
        let wait_until_available = computed.wait_until_available;
        let cloud_certs = computed.cloud_certs;
        let tcp_keepalive = computed.tcp_keepalive;
        let max_concurrency = computed.max_concurrency;
        let connect_timeout = computed.connect_timeout;

        let server_settings = computed.server_settings;

        // If we have a client security option, we need to check if it's compatible with the TLS security option.
        let tls_security = match (client_security, tls_security) {
            (ClientSecurity::Strict, TlsSecurity::Insecure | TlsSecurity::NoHostVerification) => {
                return Err(ParseError::InvalidTlsSecurity(
                    TlsSecurityError::IncompatibleSecurityOptions,
                ));
            }
            (ClientSecurity::Strict, _) => TlsSecurity::Strict,
            (ClientSecurity::InsecureDevMode, TlsSecurity::Default) => TlsSecurity::Insecure,
            (ClientSecurity::Default, TlsSecurity::Insecure) => TlsSecurity::Insecure,
            (_, TlsSecurity::Default) if tls_ca.is_none() => TlsSecurity::Strict,
            (_, TlsSecurity::Default) => TlsSecurity::NoHostVerification,
            (_, TlsSecurity::NoHostVerification) => TlsSecurity::NoHostVerification,
            (_, TlsSecurity::Strict) => TlsSecurity::Strict,
            (_, TlsSecurity::Insecure) => TlsSecurity::Insecure,
        };

        let user = user.unwrap_or_else(|| DEFAULT_USER.to_string());

        let value = Some(Config {
            host,
            db,
            user,
            authentication,
            instance_name: computed.instance,
            client_security,
            tls_security,
            tls_ca,
            tls_server_name,
            wait_until_available: wait_until_available.unwrap_or(DEFAULT_WAIT),
            server_settings,
            connect_timeout: connect_timeout.unwrap_or(DEFAULT_CONNECT_TIMEOUT),
            max_concurrency,
            tcp_keepalive: tcp_keepalive.unwrap_or(TcpKeepalive::Default),
            cloud_certs,
        });
        Ok(value)
    }
}

fn parse_dsn(dsn: &str, context: &impl BuildContext) -> Result<Params, ParseError> {
    let mut explicit = Params::default();

    context_trace!(context, "Parsing DSN: {:?}", dsn);

    let dsn = <Url as FromParamStr>::from_param_str(dsn, context)
        .map_err(|_| ParseError::InvalidDsn(InvalidDsnError::ParseError))?;

    if !(dsn.scheme() == "edgedb" || dsn.scheme() == "gel") {
        return Err(ParseError::InvalidDsn(InvalidDsnError::InvalidScheme));
    }

    let mut set = HashSet::new();
    if let Some(host) = dsn.host() {
        set.insert("host".to_string());
        match host {
            url::Host::Domain(domain) => {
                explicit.host = Param::Unparsed(domain.to_string());
            }
            url::Host::Ipv4(address) => {
                explicit.host = Param::Parsed(address.into());
            }
            url::Host::Ipv6(address) => {
                explicit.host = Param::Parsed(address.into());
            }
        }
    } else {
        explicit.host = Param::Unparsed("localhost".to_string());
    }
    if let Some(port) = dsn.port() {
        if let Some(port) = NonZeroU16::new(port) {
            set.insert("port".to_string());
            explicit.port = Param::Parsed(port.into());
        } else {
            return Err(ParseError::InvalidPort);
        }
    } else {
        explicit.port = Param::Parsed(DEFAULT_PORT);
    }

    let path = dsn.path().strip_prefix('/').unwrap_or(dsn.path());
    if !path.is_empty() {
        set.insert("branch".to_string());
        explicit.branch = Param::Unparsed(path.to_string());
        set.insert("database".to_string());
        explicit.database = Param::Unparsed(path.to_string());
    }

    if !dsn.username().is_empty() {
        set.insert("user".to_string());
        explicit.user = Param::Unparsed(dsn.username().to_string());
    }

    if let Some(password) = dsn.password() {
        if !password.is_empty() {
            set.insert("password".to_string());
            explicit.password = Param::Unparsed(password.to_string());
        }
    }

    explicit.server_settings = HashMap::new();

    for (key, value) in dsn.query_pairs() {
        // Weird case: database and branch are stripped of the leading '/'
        let value = if key == "database" || key == "branch" {
            value.strip_prefix('/').unwrap_or(value.as_ref()).into()
        } else {
            value
        };

        let (key, param) = if let Some(key) = key.strip_suffix("_file_env") {
            (key, Param::EnvFile(ParamSource::Dsn, value.to_string()))
        } else if let Some(key) = key.strip_suffix("_env") {
            (
                key,
                Param::<String>::Env(ParamSource::Dsn, value.to_string()),
            )
        } else if let Some(key) = key.strip_suffix("_file") {
            (key, Param::File(PathBuf::from(value.to_string())))
        } else {
            (key.as_ref(), Param::Unparsed(value.to_string()))
        };
        if !set.insert(key.to_string()) {
            return Err(ParseError::InvalidDsn(InvalidDsnError::DuplicateOptions(
                key.to_string(),
            )));
        }
        match key {
            "host" => explicit.host = param.cast().unwrap(),
            "user" => explicit.user = param,
            "password" => explicit.password = param,
            "secret_key" => explicit.secret_key = param,
            "tls_ca" => explicit.tls_ca = param.cast().unwrap(),
            "tls_server_name" => explicit.tls_server_name = param,
            "database" => explicit.database = param,
            "branch" => explicit.branch = param,
            "port" => explicit.port = param.cast().unwrap(),
            "tls_security" => explicit.tls_security = param.cast().unwrap(),
            "cloud_profile" => explicit.cloud_profile = param,
            "wait_until_available" => explicit.wait_until_available = param.cast().unwrap(),
            key => {
                if explicit
                    .server_settings
                    .insert(key.to_string(), value.to_string())
                    .is_some()
                {
                    return Err(ParseError::InvalidDsn(InvalidDsnError::DuplicateOptions(
                        key.to_string(),
                    )));
                }
            }
        }
    }

    if explicit.database.is_some() && explicit.branch.is_some() && path.is_empty() {
        return Err(ParseError::InvalidDsn(InvalidDsnError::BranchAndDatabase));
    }

    Ok(explicit)
}

fn parse_credentials(
    credentials: &CredentialsFile,
    context: &impl BuildContext,
) -> Result<Params, ParseError> {
    for warning in credentials.warnings() {
        context.warn(warning.clone());
    }

    Ok(credentials.into())
}

fn parse_env(context: &impl BuildContext) -> Result<Params, ParseError> {
    let mut explicit = Params {
        dsn: Param::from_parsed(Env::dsn(context)?),
        instance: Param::from_parsed(Env::instance(context)?),
        credentials: Param::from_file(Env::credentials_file(context)?),
        host: Param::from_parsed(Env::host(context)?),
        port: Param::from_parsed(Env::port(context)?.map(|p| p.into())),
        database: Param::from_parsed(Env::database(context)?),
        branch: Param::from_parsed(Env::branch(context)?),
        user: Param::from_parsed(Env::user(context)?),
        password: Param::from_parsed(Env::password(context)?),
        tls_security: Param::from_parsed(Env::client_tls_security(context)?),
        tls_ca: Param::from_unparsed(Env::tls_ca(context)?),
        tls_server_name: Param::from_parsed(Env::tls_server_name(context)?),
        client_security: Param::from_parsed(Env::client_security(context)?),
        secret_key: Param::from_parsed(Env::secret_key(context)?),
        cloud_profile: Param::from_parsed(Env::cloud_profile(context)?),
        wait_until_available: Param::from_parsed(Env::wait_until_available(context)?),
        cloud_certs: Param::from_parsed(Env::_cloud_certs(context)?),
        ..Default::default()
    };

    if explicit.branch.is_some() && explicit.database.is_some() {
        return Err(ParseError::ExclusiveOptions(
            "branch".to_string(),
            "database".to_string(),
        ));
    }

    let ca_file = Param::from_file(Env::tls_ca_file(context)?);
    if explicit.tls_ca.is_none() {
        explicit.tls_ca = ca_file;
    } else if ca_file.is_some() {
        return Err(ParseError::ExclusiveOptions(
            "tls_ca".to_string(),
            "tls_ca_file".to_string(),
        ));
    }

    Ok(explicit)
}

/// Parse the early environment variables, ensuring that we always read the
/// client security and cloud certs.
fn parse_env_early(context: &impl BuildContext) -> Result<Params, ParseError> {
    let explicit = Params {
        client_security: Param::from_parsed(Env::client_security(context)?),
        cloud_certs: Param::from_parsed(Env::_cloud_certs(context)?),
        ..Default::default()
    };

    Ok(explicit)
}

fn parse_instance(local: &str, context: &impl BuildContext) -> Result<Params, ParseError> {
    let credentials = StoredCredentials::new_ref(context);
    let Some(credentials) = (match credentials.read(InstanceName::Local(local.to_string()))? {
        Some(credentials) => Some(credentials),
        None => {
            return Err(ParseError::CredentialsFileNotFound);
        }
    }) else {
        return {
            let value = Params::default();
            Ok(value)
        };
    };
    parse_credentials(&credentials, context)
}

fn parse_cloud(profile: &str, context: &impl BuildContext) -> Result<Params, ParseError> {
    let mut explicit = Params::default();

    let Some(cloud_credentials): Option<CloudCredentialsFile> =
        context.read_config_file(Path::new("cloud-credentials").join(format!("{profile}.json")))?
    else {
        return {
            let value = Params::default();
            Ok(value)
        };
    };
    explicit.secret_key = Param::Unparsed(cloud_credentials.secret_key);

    Ok(explicit)
}

/// Parse the connection from the given sources given the following precedence:
///
/// 1. Explicit options
/// 2. Environment variables (GEL_DSN / GEL_INSTANCE / GEL_CREDENTIALS_FILE / GEL_HOST+GEL_PORT)
///
/// If no explicit options or environment variables were provided, the project-linked credentials will be used.
///
pub(crate) fn parse(
    mut explicit: Params,
    context: &impl BuildContext,
    project: Option<ProjectDir>,
) -> Result<Config, ParseError> {
    // We always want to read the early environment variables.
    let env_params = parse_env_early(context)?;
    explicit.merge(env_params);

    if let Some(config) = explicit.try_build(context, BuildPhase::Options)? {
        return Ok(config);
    }

    let env_params = parse_env(context)?;
    explicit.merge(env_params);

    if let Some(config) = explicit.try_build(context, BuildPhase::Environment)? {
        return Ok(config);
    }

    if let Some(project) = project {
        if let Ok(Some(project)) = find_project_file(context, project) {
            if let Some(project) = project.project {
                explicit.merge(Params {
                    cloud_profile: Param::from_unparsed(project.cloud_profile),
                    instance: Param::from_parsed(Some(project.instance_name)),
                    database: Param::from_unparsed(project.database),
                    branch: Param::from_unparsed(project.branch),
                    ..Default::default()
                });
            } else {
                return Err(ParseError::ProjectNotInitialised);
            }
        }
    }

    if let Some(config) = explicit.try_build(context, BuildPhase::Project)? {
        return Ok(config);
    }

    Err(ParseError::NoOptionsOrToml)
}

pub(crate) fn compute(
    mut explicit: Params,
    context: &impl BuildContext,
    project: Option<ProjectDir>,
) -> Result<(Computed, Vec<ParseError>), ParseError> {
    // We always want to read the early environment variables.
    let env_params = parse_env_early(context)?;
    explicit.merge(env_params);

    let (computed, mut errors) = explicit.try_compute(context, BuildPhase::Options)?;
    if computed.is_complete() {
        return Ok((computed, errors));
    }

    let env_params = parse_env(context)?;
    explicit.merge(env_params);

    let (computed, env_errors) = explicit.try_compute(context, BuildPhase::Environment)?;
    errors.extend(env_errors);
    if computed.is_complete() {
        return Ok((computed, errors));
    }

    if let Some(project) = project {
        if let Ok(Some(project)) = find_project_file(context, project) {
            if let Some(project) = project.project {
                explicit.merge(Params {
                    cloud_profile: Param::from_unparsed(project.cloud_profile),
                    instance: Param::from_parsed(Some(project.instance_name)),
                    database: Param::from_unparsed(project.database),
                    branch: Param::from_unparsed(project.branch),
                    ..Default::default()
                });
            } else {
                return Err(ParseError::ProjectNotInitialised);
            }
        }
    }

    let (computed, project_errors) = explicit.try_compute(context, BuildPhase::Project)?;
    errors.extend(project_errors);

    Ok((computed, errors))
}

#[cfg(test)]
mod tests {
    use crate::host::LOCALHOST;

    use super::*;

    #[test]
    fn test_parse() {
        let _params = Builder::default().without_system();
        let _params = Builder::default()
            .with_fs()
            .with_explicit_project(Path::new("."));
        // This intentionally won't work
        // let params = Builder::default().with_env().project_dir(Path::new("."));
    }

    #[cfg(unix)]
    #[test]
    fn test_with_unix_socket() {
        let params = Builder::default()
            .unix_path(Path::new("/"))
            .without_system()
            .build()
            .expect("Just a unix path is OK");
        assert_eq!(params.host.to_string(), "/");
        eprintln!("{params:?}");

        let params = Builder::default()
            .unix_path(UnixPath::with_port_suffix(PathBuf::from(
                "/.s.EDGEDB.admin.",
            )))
            .port(1234)
            .without_system()
            .build()
            .expect("Unix path and port is OK");
        assert_eq!(params.host.to_string(), "/.s.EDGEDB.admin.1234");
        eprintln!("{params:?}");

        // Pull the port from the credentials.
        let params = Builder::default()
            .instance(InstanceName::Local("instancename".to_string()))
            .unix_path(UnixPath::with_port_suffix(PathBuf::from("/tmp/port.")))
            .without_system()
            .with_fs_impl(HashMap::from_iter([(
                PathBuf::from("/home/edgedb/.config/edgedb/credentials/instancename.json"),
                r#"{ "user": "user", "port": 12345 }"#.to_string(),
            )]))
            .with_user_impl("edgedb")
            .build()
            .expect("Unix path and instance is OK");
        assert_eq!(params.host.to_string(), "/tmp/port.12345");
        assert_eq!(
            params.instance_name,
            Some(InstanceName::Local("instancename".to_string()))
        );
        eprintln!("{params:?}");
    }

    #[test]
    fn test_credentials_file() {
        let credentials = CredentialsFile::default();
        assert_eq!(
            Params::from(&credentials),
            Params {
                host: Param::from_parsed(Some(LOCALHOST.clone())),
                port: Param::from_parsed(Some(5656)),
                tls_security: Param::from_parsed(Some(TlsSecurity::Default)),
                ..Default::default()
            }
        );
        assert_eq!(
            Params::from(credentials),
            Params {
                host: Param::from_parsed(Some(LOCALHOST.clone())),
                port: Param::from_parsed(Some(5656)),
                tls_security: Param::from_parsed(Some(TlsSecurity::Default)),
                ..Default::default()
            }
        );

        let credentials = CredentialsFile {
            password: Some("password".to_string()),
            ..Default::default()
        };
        assert_eq!(
            Params::from(&credentials),
            Params {
                host: Param::from_parsed(Some(LOCALHOST.clone())),
                port: Param::from_parsed(Some(5656)),
                password: Param::from_unparsed(Some("password".to_string())),
                tls_security: Param::from_parsed(Some(TlsSecurity::Default)),
                ..Default::default()
            }
        );
    }
}