error_handling: use explicit thiserror over snafu + anyhow mixture

For now, drop snafu due to proc-macro magic that makes error handling in
code non-obvious. This is a first step towards transitioning to anyhow
or another application-based error handling strategy.

Cargo.toml

@@ -28,7 +28,7 @@ tracing-appender = "0.2.3"
 tracing-subscriber = { version = "0.3.18", features = ["fmt", "env-filter", "std", "registry"] }
 tokio = "1.35.1"
 reqwest = { version = "0.11.23", default-features = false, features = ["blocking", "rustls", "json"] }
-snafu = "0.8.0"
+thiserror = "1"
 
 [package]
 name = "mint"
@@ -80,7 +80,6 @@ sha2 = "0.10.8"
 steamlocate.workspace = true
 task-local-extensions = "0.1.4"
 tempfile = "3.9.0"
-thiserror = "1.0.56"
 tokio = { workspace = true, features = ["full"] }
 tracing.workspace = true
 typetag = "0.2.16"
@@ -92,7 +91,7 @@ repak.workspace = true
 include_dir = "0.7.3"
 postcard.workspace = true
 fs-err.workspace = true
-snafu.workspace = true
+thiserror.workspace = true
 strum = { version = "0.26", features = ["derive"] }
 itertools.workspace = true
 egui_dnd = "0.6.0"

mint_lib/Cargo.toml

@@ -17,4 +17,4 @@ tracing.workspace = true
 tracing-appender.workspace = true
 tracing-subscriber.workspace = true
 reqwest.workspace = true
-snafu.workspace = true
+thiserror.workspace = true

mint_lib/src/error.rs

@@ -1,32 +1,27 @@
-use snafu::Snafu;
+use thiserror::Error;
 
-#[derive(Debug, Snafu)]
-#[snafu(display("mint encountered an error: {msg}"))]
-pub struct GenericError {
-    pub msg: String,
-}
+/// Possible errors when using the mint lib.
+#[derive(Debug, Error)]
+#[non_exhaustive]
+pub enum MintError {
+    /// Failed to update.
+    #[error("failed to fetch github release: {summary}")]
+    FetchGithubReleaseFailed {
+        summary: String,
+        details: Option<String>,
+    },
 
-pub trait ResultExt<T, E> {
-    fn generic(self, msg: String) -> Result<T, GenericError>;
-    fn with_generic<F>(self, f: F) -> Result<T, GenericError>
-    where
-        F: FnOnce(E) -> String;
-}
+    /// Failed to locate Deep Rock Galactic installation.
+    #[error("unable to locate Deep Rock Galactic installation: {summary}")]
+    UnknownInstallation {
+        summary: String,
+        details: Option<String>,
+    },
 
-impl<T, E> ResultExt<T, E> for Result<T, E> {
-    fn generic(self, msg: String) -> Result<T, GenericError> {
-        match self {
-            Ok(ok) => Ok(ok),
-            Err(_) => Err(GenericError { msg }),
-        }
-    }
-    fn with_generic<F>(self, f: F) -> Result<T, GenericError>
-    where
-        F: FnOnce(E) -> String,
-    {
-        match self {
-            Ok(ok) => Ok(ok),
-            Err(e) => Err(GenericError { msg: f(e) }),
-        }
-    }
+    /// Failed to setup tracing.
+    #[error("failed to setup logging")]
+    LogSetupFailed {
+        summary: String,
+        details: Option<String>,
+    },
 }

mint_lib/src/installation.rs

@@ -0,0 +1,203 @@
+use std::path::{Path, PathBuf};
+
+use crate::MintError;
+
+#[derive(Debug)]
+pub enum DRGInstallationType {
+    Steam,
+    Xbox,
+}
+
+fn io_err<S: AsRef<str>>(e: std::io::Error, msg: S) -> MintError {
+    MintError::UnknownInstallation {
+        summary: msg.as_ref().to_string(),
+        details: Some(e.to_string()),
+    }
+}
+
+fn bad_file_name<S: AsRef<str>>(msg: S) -> MintError {
+    MintError::UnknownInstallation {
+        summary: msg.as_ref().to_string(),
+        details: None,
+    }
+}
+
+fn unexpected_file_name<S: AsRef<str>>(msg: S, expected: &[&str], found: &str) -> MintError {
+    let candidates = expected
+        .iter()
+        .map(|e| format!("\"{e}\""))
+        .collect::<Vec<_>>();
+    let candidates = candidates.join(", ");
+    let expectation = format!("expected one of [{candidates}] but found \"{found}\"");
+
+    MintError::UnknownInstallation {
+        summary: msg.as_ref().to_string(),
+        details: Some(expectation),
+    }
+}
+
+fn mk_lowercase_file_name<P: AsRef<Path>, S: AsRef<str>>(
+    path: P,
+    err_msg: S,
+) -> Result<String, MintError> {
+    let Some(mut file_name) = path
+        .as_ref()
+        .file_name()
+        .map(|n| n.to_string_lossy().to_string())
+    else {
+        return Err(bad_file_name(err_msg));
+    };
+    file_name.make_ascii_lowercase();
+    Ok(file_name)
+}
+
+const STEAM_EXE_FILE_NAME: &str = "fsd-win64-shipping.exe";
+const XBOX_EXE_FILE_NAME: &str = "fsd-wingdk-shipping.exe";
+
+const STEAM_PAK_FILE_NAME: &str = "fsd-windowsnoeditor.pak";
+const XBOX_PAK_FILE_NAME: &str = "fsd-wingdk.pak";
+
+impl DRGInstallationType {
+    pub fn from_exe_path() -> Result<Self, MintError> {
+        let exe_path = std::env::current_exe()
+            .map_err(|e| io_err(e, "failed to get path of current executable"))?;
+
+        let file_name = mk_lowercase_file_name(
+            exe_path,
+            "unable to get file name component of executable path",
+        )?;
+
+        match file_name.as_ref() {
+            STEAM_EXE_FILE_NAME => Ok(Self::Steam),
+            XBOX_EXE_FILE_NAME => Ok(Self::Xbox),
+            n => Err(unexpected_file_name(
+                "unexpected executable file name",
+                &[STEAM_EXE_FILE_NAME, XBOX_EXE_FILE_NAME],
+                n,
+            )),
+        }
+    }
+
+    pub fn from_pak_path<P: AsRef<Path>>(pak: P) -> Result<Self, MintError> {
+        let file_name = mk_lowercase_file_name(pak, "failed to get pak file name")?;
+        match file_name.as_ref() {
+            STEAM_PAK_FILE_NAME => Ok(Self::Steam),
+            XBOX_PAK_FILE_NAME => Ok(Self::Steam),
+            n => Err(unexpected_file_name(
+                "unexpected pak file name",
+                &[STEAM_PAK_FILE_NAME, XBOX_PAK_FILE_NAME],
+                n,
+            )),
+        }
+    }
+
+    pub fn binaries_directory_name(&self) -> &'static str {
+        match self {
+            Self::Steam => "Win64",
+            Self::Xbox => "WinGDK",
+        }
+    }
+
+    pub fn main_pak_name(&self) -> &'static str {
+        match self {
+            Self::Steam => "FSD-WindowsNoEditor.pak",
+            Self::Xbox => "FSD-WinGDK.pak",
+        }
+    }
+
+    pub fn hook_dll_name(&self) -> &'static str {
+        match self {
+            Self::Steam => "x3daudio1_7.dll",
+            Self::Xbox => "d3d9.dll",
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct DRGInstallation {
+    pub root: PathBuf,
+    pub installation_type: DRGInstallationType,
+}
+
+impl DRGInstallation {
+    /// Returns first DRG installation found. Only supports Steam version.
+    /// TODO locate Xbox version
+    pub fn find() -> Option<Self> {
+        steamlocate::SteamDir::locate()
+            .ok()
+            .and_then(|steamdir| {
+                steamdir
+                    .find_app(548430)
+                    .ok()
+                    .flatten()
+                    .map(|(app, library)| {
+                        library
+                            .resolve_app_dir(&app)
+                            .join("FSD/Content/Paks/FSD-WindowsNoEditor.pak")
+                    })
+            })
+            .and_then(|path| Self::from_pak_path(path).ok())
+    }
+
+    pub fn from_pak_path<P: AsRef<Path>>(pak: P) -> Result<Self, MintError> {
+        let pak_root = pak
+            .as_ref()
+            .parent()
+            .and_then(Path::parent)
+            .and_then(Path::parent);
+
+        match pak_root {
+            Some(root) => Ok(Self {
+                root: root.to_path_buf(),
+                installation_type: DRGInstallationType::from_pak_path(pak)?,
+            }),
+            None => Err(MintError::UnknownInstallation {
+                summary: "failed to determine pak root".to_string(),
+                details: Some(format!("given path was {}", pak.as_ref().display())),
+            }),
+        }
+    }
+
+    pub fn binaries_directory(&self) -> PathBuf {
+        self.root
+            .join("Binaries")
+            .join(self.installation_type.binaries_directory_name())
+    }
+
+    pub fn paks_path(&self) -> PathBuf {
+        self.root.join("Content").join("Paks")
+    }
+
+    pub fn main_pak(&self) -> PathBuf {
+        self.root
+            .join("Content")
+            .join("Paks")
+            .join(self.installation_type.main_pak_name())
+    }
+
+    pub fn modio_directory(&self) -> Option<PathBuf> {
+        match self.installation_type {
+            DRGInstallationType::Steam => {
+                #[cfg(target_os = "windows")]
+                {
+                    Some(PathBuf::from("C:\\Users\\Public\\mod.io\\2475"))
+                }
+                #[cfg(target_os = "linux")]
+                {
+                    steamlocate::SteamDir::locate()
+                        .map(|s| {
+                            s.path().join(
+                                "steamapps/compatdata/548430/pfx/drive_c/users/Public/mod.io/2475",
+                            )
+                        })
+                        .ok()
+                }
+                #[cfg(not(any(target_os = "windows", target_os = "linux")))]
+                {
+                    None // TODO
+                }
+            }
+            DRGInstallationType::Xbox => None,
+        }
+    }
+}