Resolve audio not loading bug

Ensure all assets are downloading for each version

Temporarily disable minecraft versions older than 1.8 because of the asset/manifest loading issues

Implement basic documentation of modules

Implement basic async/multithreading for downloading assets

18 files changed, 488 insertions, 100 deletions

diff --git a/.gitignore b/.gitignore
index 6aedc81..d0f7565 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,4 @@ Cargo.lock
 **/*.rs.bk
 *.pdb
 rust-project.json
+*.png
diff --git a/clippy.toml b/clippy.toml
index f688e0a..6b15c5a 100644
--- a/clippy.toml
+++ b/clippy.toml
@@ -1,8 +1,8 @@
 stack-size-threshold = 393216
 future-size-threshold = 24576
 array-size-threshold = 4096
-large-error-threshold = 256                 # TODO reduce me ALARA
-too-many-lines-threshold = 100              # TODO reduce me to <= 100
+large-error-threshold = 256                
+too-many-lines-threshold = 100              
 excessive-nesting-threshold = 3
-type-complexity-threshold = 250             # reduce me to ~200
-cognitive-complexity-threshold = 100        # TODO reduce me ALARA
+type-complexity-threshold = 250            
+cognitive-complexity-threshold = 100       
diff --git a/rustfmt.toml b/rustfmt.toml
index 32fb2b2..68c25df 100644
--- a/rustfmt.toml
+++ b/rustfmt.toml
@@ -16,7 +16,7 @@ imports_granularity = "Crate"
 match_arm_blocks = false
 match_arm_leading_pipes = "Always"
 match_block_trailing_comma = true
-max_width = 98
+max_width = 80
 newline_style = "Unix"
 normalize_comments = false
 overflow_delimited_expr = true
diff --git a/src/config/loader.rs b/src/config/loader.rs
index 81a4351..d4b142e 100644
--- a/src/config/loader.rs
+++ b/src/config/loader.rs
@@ -1,9 +1,9 @@
-use std::{env, path::PathBuf};
+use std::{env::var, fs::read_to_string, path::PathBuf};
 
+use directories::ProjectDirs;
 use serde::Deserialize;
 
 use crate::{constants::*, errors::McError};
-
 #[allow(dead_code)]
 #[derive(Debug, Deserialize)]
 pub struct Config {
@@ -18,37 +18,33 @@ pub struct Config {
     #[serde(default)]
     pub jvm_args: Vec<String>,
 }
-
 impl Config {
     pub fn load() -> Result<Self, McError> {
         let cfg_path = default_config_path()?;
         let mut cfg: Config = if cfg_path.exists() {
-            let txt = std::fs::read_to_string(&cfg_path)?;
+            let txt = read_to_string(&cfg_path)?;
             toml::from_str(&txt).map_err(|e| McError::Config(e.to_string()))?
         } else {
             Self::default()
         };
-
-        if let Ok(v) = env::var("MC_USERNAME") {
+        if let Ok(v) = var("MC_USERNAME") {
             cfg.username = v;
         }
-        if let Ok(v) = env::var("MC_VERSION") {
+        if let Ok(v) = var("MC_VERSION") {
             cfg.version = v;
         }
-        if let Ok(v) = env::var("MC_JAVA_PATH") {
+        if let Ok(v) = var("MC_JAVA_PATH") {
             cfg.java_path = v;
         }
-        if let Ok(v) = env::var("MC_MAX_MEMORY_MB") {
+        if let Ok(v) = var("MC_MAX_MEMORY_MB") {
             cfg.max_memory_mb = v.parse().unwrap_or(cfg.max_memory_mb);
         }
-
         Ok(cfg)
     }
 
     fn default() -> Self {
         let base =
-            directories::ProjectDirs::from("com", "example", "mccl").expect("platform dirs");
-
+            ProjectDirs::from("com", "example", "dml").expect("platform dirs");
         Self {
             username: "Player".into(),
             uuid: uuid::Uuid::new_v4().to_string(),
@@ -62,9 +58,8 @@ impl Config {
         }
     }
 }
-
 fn default_config_path() -> Result<PathBuf, McError> {
-    let base = directories::ProjectDirs::from("com", "example", "mccl")
+    let base = ProjectDirs::from("com", "example", "dml")
         .ok_or_else(|| McError::Config("cannot determine config dir".into()))?;
     Ok(base.config_dir().join("config.toml"))
 }
diff --git a/src/config/mod.rs b/src/config/mod.rs
index c5fc004..066154a 100644
--- a/src/config/mod.rs
+++ b/src/config/mod.rs
@@ -1,3 +1,12 @@
-pub mod loader;
+//! Configuration module for the DML launcher.
+//!
+//! This module contains submodules and helpers for loading, parsing, and
+//! managing configuration files and settings. It abstracts the details
+//! of where configuration is stored and how it is represented in memory.
+//!
+//! # Submodules
+//! - `loader`: Functions to load and parse configuration from disk or
+//!   environment variables.
 
+pub mod loader;
 pub use loader::Config;
diff --git a/src/constants.rs b/src/constants.rs
index 52833b2..3234fe6 100644
--- a/src/constants.rs
+++ b/src/constants.rs
@@ -8,6 +8,6 @@ pub const VERSION_MANIFEST_URL: &str =
 pub const DOWNLOAD_RETRIES: usize = 3;
 pub const DOWNLOAD_BACKOFF: Duration = Duration::from_millis(400);
 
-pub const DEFAULT_MAX_MEMORY_MB: u32 = 2048;
+pub const DEFAULT_MAX_MEMORY_MB: u32 = 4048;
 pub const DEFAULT_JAVA_PATH: &str = "java";
 pub const DEFAULT_VERSION: &str = "latest";
diff --git a/src/errors.rs b/src/errors.rs
index c167733..b98ae2d 100644
--- a/src/errors.rs
+++ b/src/errors.rs
@@ -1,20 +1,31 @@
 use std::{fmt, io};
 
+use fmt::{Display, Formatter, Result};
+use zip::result::ZipError;
+
+/// Represents all possible errors that can occur in the DML launcher.
+///
+/// This enum centralizes error handling for the entire application,
+/// wrapping various underlying error types from I/O, HTTP requests,
+/// JSON parsing, ZIP extraction, configuration issues, and runtime errors.
 #[allow(dead_code)]
 #[derive(Debug)]
 pub enum McError {
     Io(io::Error),
     Http(reqwest::Error),
     Json(serde_json::Error),
-    Zip(zip::result::ZipError),
+    Zip(ZipError),
     Config(String),
     ShaMismatch(String),
     Process(String),
-    Runtime(String), // ← NEW
+    Runtime(String),
 }
 
-impl fmt::Display for McError {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "{:?}", self) }
+impl Display for McError {
+    /// Formats the error for user-friendly display.
+    ///
+    /// Currently, it uses the `Debug` format for simplicity.
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result { write!(f, "{:?}", self) }
 }
 
 impl From<io::Error> for McError {
@@ -29,6 +40,6 @@ impl From<serde_json::Error> for McError {
     fn from(e: serde_json::Error) -> Self { Self::Json(e) }
 }
 
-impl From<zip::result::ZipError> for McError {
-    fn from(e: zip::result::ZipError) -> Self { Self::Zip(e) }
+impl From<ZipError> for McError {
+    fn from(e: ZipError) -> Self { Self::Zip(e) }
 }
diff --git a/src/main.rs b/src/main.rs
index 8a01b9f..e229a3e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -8,9 +8,15 @@ mod util;
 
 use clap::Parser;
 use config::Config;
+use dotenvy::dotenv;
 use errors::McError;
 use log::{debug, info};
 
+use crate::minecraft::{
+    downloads::download_all, extraction::extract_natives, launcher::launch,
+    manifests,
+};
+
 #[derive(Parser, Debug)]
 #[command(author, about, disable_version_flag = true)]
 struct Cli {
@@ -26,7 +32,7 @@ struct Cli {
 
 #[tokio::main]
 async fn main() -> Result<(), McError> {
-    dotenvy::dotenv().ok();
+    dotenv().ok();
     env_logger::init();
 
     let cli = Cli::parse();
@@ -48,13 +54,13 @@ async fn main() -> Result<(), McError> {
     platform::paths::ensure_dirs(&config)?;
     info!("Using Minecraft version {}", config.version);
 
-    let version = minecraft::manifests::load_version(&config).await?;
+    let version = manifests::load_version(&config).await?;
     info!("Loaded version manifest for: {}", version.id);
     debug!("Main class: {}", version.main_class);
 
-    minecraft::downloads::download_all(&config, &version).await?;
-    minecraft::extraction::extract_natives(&config, &version)?;
-    minecraft::launcher::launch(&config, &version)?;
+    download_all(&config, &version).await?;
+    extract_natives(&config, &version)?;
+    launch(&config, &version)?;
 
     Ok(())
 }
diff --git a/src/minecraft/downloads.rs b/src/minecraft/downloads.rs
index 5be5a05..a994146 100644
--- a/src/minecraft/downloads.rs
+++ b/src/minecraft/downloads.rs
@@ -1,5 +1,10 @@
 use log::{debug, info};
-use tokio::{fs, io::AsyncWriteExt};
+use reqwest::get;
+use serde::Deserialize;
+use tokio::{
+    fs::{self, File, create_dir_all},
+    io::AsyncWriteExt,
+};
 
 use crate::{
     config::Config,
@@ -8,58 +13,181 @@ use crate::{
     platform::paths,
 };
 
-/// Download everything required to launch:
+#[derive(Debug, Deserialize)]
+struct AssetObject {
+    hash: String,
+    size: u64,
+}
+
+#[derive(Debug, Deserialize)]
+struct AssetIndexManifest {
+    objects: std::collections::HashMap<String, AssetObject>,
+}
+
+/// Pobiera wszystko potrzebne do uruchomienia Minecraft:
 /// - client jar
-/// - libraries
-pub async fn download_all(config: &Config, version: &Version) -> Result<(), McError> {
+/// - biblioteki (artifact + natives)
+/// - assets (w tym textures, sounds)
+pub async fn download_all(
+    config: &Config,
+    version: &Version,
+) -> Result<(), McError> {
     download_client(config, version).await?;
     download_libraries(config, &version.libraries).await?;
+    download_assets(config, version).await?;
     Ok(())
 }
 
-async fn download_client(config: &Config, version: &Version) -> Result<(), McError> {
+async fn download_client(
+    config: &Config,
+    version: &Version,
+) -> Result<(), McError> {
     let jar_path = paths::client_jar(config, &version.id)?;
 
     if jar_path.exists() {
-        debug!("Client jar already exists");
+        debug!("Client jar already exists: {}", jar_path.display());
         return Ok(());
     }
 
     info!("Downloading client {}", version.id);
-
     download_file(&version.downloads.client.url, &jar_path).await
 }
 
-async fn download_libraries(config: &Config, libraries: &[Library]) -> Result<(), McError> {
-    for lib in libraries {
-        let Some(artifact) = &lib.downloads.artifact else {
-            continue;
-        };
+async fn download_libraries(
+    config: &Config,
+    libraries: &[Library],
+) -> Result<(), McError> {
+    for library in libraries {
+        // ===== CLASSPATH LIBRARIES =====
+        if let Some(artifact) = &library.downloads.artifact {
+            let library_path = paths::library_file(config, &artifact.path)?;
+
+            if !library_path.exists() {
+                info!("Downloading library {}", artifact.path);
+                download_file(&artifact.url, &library_path).await?;
+            }
+        }
+
+        // ===== NATIVES =====
+        if let Some(classifiers) = &library.downloads.classifiers {
+            for (_, native) in classifiers {
+                let native_path = paths::library_file(config, &native.path)?;
+
+                if native_path.exists() {
+                    continue;
+                }
+
+                info!("Downloading native library {}", native.path);
+                download_file(&native.url, &native_path).await?;
+            }
+        }
+    }
+
+    Ok(())
+}
 
-        let lib_path = paths::library_file(config, &artifact.path)?;
+async fn download_asset_index(
+    config: &Config,
+    version: &Version,
+) -> Result<AssetIndexManifest, McError> {
+    let assets_dir = paths::assets_dir(config);
+    create_dir_all(assets_dir.join("indexes")).await?;
+
+    let asset_index = version.asset_index.as_ref().ok_or_else(|| {
+        McError::Config("Missing asset_index in version.json".into())
+    })?;
+
+    // Nie pozwalamy na legacy dla nowoczesnych wersji
+    if asset_index.id == "legacy" {
+        return Err(McError::Config(
+            "Legacy assetIndex detected – pobierz właściwy version.json".into(),
+        ));
+    }
+
+    let index_path = assets_dir
+        .join("indexes")
+        .join(format!("{}.json", asset_index.id));
+
+    // Jeśli indeks istnieje lokalnie
+    if index_path.exists() {
+        let index_data = fs::read_to_string(&index_path).await?;
+        let manifest: AssetIndexManifest = serde_json::from_str(&index_data)?;
+        return Ok(manifest);
+    }
+
+    // Pobierz indeks z sieci
+    info!("Downloading asset index {}", asset_index.id);
+    let response = get(&asset_index.url).await?;
+    let manifest_text = response.text().await?;
+
+    fs::write(&index_path, &manifest_text).await?;
+
+    let manifest: AssetIndexManifest = serde_json::from_str(&manifest_text)?;
+    Ok(manifest)
+}
 
-        if lib_path.exists() {
+async fn download_assets(
+    config: &Config,
+    version: &Version,
+) -> Result<(), McError> {
+    let assets_dir = paths::assets_dir(config);
+
+    // Katalogi MUSZĄ istnieć
+    create_dir_all(assets_dir.join("objects")).await?;
+    create_dir_all(assets_dir.join("indexes")).await?;
+
+    let manifest = download_asset_index(config, version).await?;
+
+    // Pobieramy wszystkie obiekty
+    for (logical_path, asset) in &manifest.objects {
+        let subdir = &asset.hash[0..2];
+        let file_path = assets_dir
+            .join("objects")
+            .join(subdir)
+            .join(&asset.hash);
+
+        if file_path.exists() {
             continue;
         }
 
-        info!("Downloading library {}", artifact.path);
-        download_file(&artifact.url, &lib_path).await?;
+        let url = format!(
+            "https://resources.download.minecraft.net/{}/{}",
+            subdir, asset.hash
+        );
+        info!("Downloading asset {} -> {}", logical_path, file_path.display());
+        download_file(&url, &file_path).await?;
+    }
+
+    // Pobierz sounds.json jeśli istnieje
+    if let Some(asset) = manifest.objects.get("sounds.json") {
+        let file_path = assets_dir.join("indexes").join("sounds.json");
+        if !file_path.exists() {
+            let subdir = &asset.hash[0..2];
+            let url = format!(
+                "https://resources.download.minecraft.net/{}/{}",
+                subdir, asset.hash
+            );
+            info!("Downloading sounds.json");
+            download_file(&url, &file_path).await?;
+        }
     }
 
     Ok(())
 }
 
-/* ---------------- helper ---------------- */
-
-async fn download_file(url: &str, path: &std::path::Path) -> Result<(), McError> {
+/// Helper do pobierania plików
+async fn download_file(
+    url: &str,
+    path: &std::path::Path,
+) -> Result<(), McError> {
     if let Some(parent) = path.parent() {
-        fs::create_dir_all(parent).await?;
+        create_dir_all(parent).await?;
     }
 
-    let response = reqwest::get(url).await?;
+    let response = get(url).await?;
     let bytes = response.bytes().await?;
 
-    let mut file = fs::File::create(path).await?;
+    let mut file = File::create(path).await?;
     file.write_all(&bytes).await?;
 
     Ok(())
diff --git a/src/minecraft/extraction.rs b/src/minecraft/extraction.rs
index 5175ee0..b58fd2e 100644
--- a/src/minecraft/extraction.rs
+++ b/src/minecraft/extraction.rs
@@ -1,10 +1,118 @@
+use std::{fs, io, path::Path};
+
 use log::info;
+use zip::ZipArchive;
+
+use crate::{
+    errors::McError,
+    minecraft::manifests::{Library, Version},
+};
 
-use crate::errors::McError;
 pub fn extract_natives(
-    _cfg: &crate::config::Config,
-    version: &crate::minecraft::manifests::Version,
+    cfg: &crate::config::Config,
+    version: &Version,
 ) -> Result<(), McError> {
-    info!("Extracting natives for {}", version.id);
+    let natives_dir = cfg
+        .data_dir
+        .join("minecraft")
+        .join("versions")
+        .join(&version.id)
+        .join("natives");
+
+    info!("Extracting natives for {} into {:?}", version.id, natives_dir);
+
+    if natives_dir.exists() {
+        fs::remove_dir_all(&natives_dir)?;
+    }
+    fs::create_dir_all(&natives_dir)?;
+
+    for lib in &version.libraries {
+        if !library_allowed(lib) {
+            continue;
+        }
+
+        let natives = match &lib.natives {
+            | Some(n) => n,
+            | None => continue,
+        };
+
+        let classifier = match natives.get("linux") {
+            | Some(c) => c,
+            | None => continue,
+        };
+
+        let classifiers = match &lib.downloads.classifiers {
+            | Some(c) => c,
+            | None => continue,
+        };
+
+        let artifact = match classifiers.get(classifier) {
+            | Some(a) => a,
+            | None => continue,
+        };
+
+        let jar_path = cfg
+            .data_dir
+            .join("minecraft")
+            .join("libraries")
+            .join(&artifact.path);
+
+        info!("Extracting natives from {:?}", jar_path);
+
+        extract_zip(&jar_path, &natives_dir)?;
+    }
+
+    Ok(())
+}
+
+fn library_allowed(lib: &Library) -> bool {
+    let rules = match &lib.rules {
+        | Some(r) => r,
+        | None => return true,
+    };
+
+    let mut allowed = false;
+
+    for rule in rules {
+        let os_match = match &rule.os {
+            | Some(os) => os.name == "linux",
+            | None => true,
+        };
+
+        if os_match {
+            allowed = rule.action == "allow";
+        }
+    }
+
+    allowed
+}
+
+fn extract_zip(jar_path: &Path, out_dir: &Path) -> Result<(), McError> {
+    let file = fs::File::open(jar_path)?;
+    let mut zip = ZipArchive::new(file)?;
+
+    for i in 0..zip.len() {
+        let mut entry = zip.by_index(i)?;
+        let name = entry.name();
+
+        if name.starts_with("META-INF/") {
+            continue;
+        }
+
+        let out_path = out_dir.join(name);
+
+        if entry.is_dir() {
+            fs::create_dir_all(&out_path)?;
+            continue;
+        }
+
+        if let Some(parent) = out_path.parent() {
+            fs::create_dir_all(parent)?;
+        }
+
+        let mut out_file = fs::File::create(&out_path)?;
+        io::copy(&mut entry, &mut out_file)?;
+    }
+
     Ok(())
 }
diff --git a/src/minecraft/launcher.rs b/src/minecraft/launcher.rs
index f7e3ecc..cfd6c85 100644
--- a/src/minecraft/launcher.rs
+++ b/src/minecraft/launcher.rs
@@ -2,26 +2,39 @@ use std::process::Command;
 
 use log::{debug, info};
 
-use crate::{config::Config, errors::McError, minecraft::manifests::Version, platform::paths};
+use crate::{
+    config::Config,
+    errors::McError,
+    minecraft::manifests::{Library, Version},
+    platform::paths,
+};
 
-/// Build the full classpath
-fn build_classpath(config: &Config, version: &Version) -> Result<String, McError> {
+/// Buduje classpath dla danej wersji Minecrafta
+fn build_classpath(
+    config: &Config,
+    version: &Version,
+) -> Result<String, McError> {
     let sep = if cfg!(windows) { ";" } else { ":" };
     let mut entries = Vec::new();
 
-    for lib in &version.libraries {
-        if let Some(artifact) = &lib.downloads.artifact {
+    for library in &version.libraries {
+        if !library_allowed(library) {
+            continue;
+        }
+        if let Some(artifact) = &library.downloads.artifact {
             let path = paths::library_file(config, &artifact.path)?;
             entries.push(path.to_string_lossy().to_string());
         }
     }
 
+    // client.jar zawsze na końcu classpath
     let client_jar = paths::client_jar(config, &version.id)?;
     entries.push(client_jar.to_string_lossy().to_string());
+
     Ok(entries.join(sep))
 }
 
-/// Launch Minecraft
+/// Uruchamia Minecraft
 pub fn launch(config: &Config, version: &Version) -> Result<(), McError> {
     let java = &config.java_path;
     let classpath = build_classpath(config, version)?;
@@ -34,26 +47,46 @@ pub fn launch(config: &Config, version: &Version) -> Result<(), McError> {
         )));
     }
 
+    let asset_index_id = version
+        .asset_index
+        .as_ref()
+        .ok_or_else(|| {
+            McError::Runtime("Missing assetIndex in version.json".into())
+        })?
+        .id
+        .clone();
+
     info!("Launching Minecraft {}", version.id);
     debug!("Classpath: {}", classpath);
     debug!("Natives: {}", natives_dir.display());
+    debug!("Asset index: {}", asset_index_id);
+
+    let mut cmd = Command::new(java);
+
+    // ===== JVM ARGUMENTS (muszą być na początku) =====
+    cmd.arg(format!("-Xmx{}M", config.max_memory_mb))
+        .arg(format!("-Djava.library.path={}", natives_dir.display()));
 
-    let status = Command::new(java)
-        .arg(format!("-Xmx{}M", config.max_memory_mb))
-        .arg(format!("-Djava.library.path={}", natives_dir.display()))
-        .arg("-cp")
+    for arg in &config.jvm_args {
+        cmd.arg(arg);
+    }
+
+    // ===== CLASSPATH + MAIN CLASS =====
+    cmd.arg("-cp")
         .arg(classpath)
-        .arg(&version.main_class)
-        .arg("--username")
+        .arg(&version.main_class);
+
+    // ===== ARGUMENTY GRY =====
+    cmd.arg("--username")
         .arg(&config.username)
         .arg("--version")
         .arg(&version.id)
         .arg("--gameDir")
-        .arg(paths::minecraft_root(config))
+        .arg(paths::game_dir(config))
         .arg("--assetsDir")
-        .arg(paths::minecraft_root(config).join("assets"))
+        .arg(paths::assets_dir(config))
         .arg("--assetIndex")
-        .arg(&version.id)
+        .arg(&asset_index_id)
         .arg("--uuid")
         .arg(&config.uuid)
         .arg("--userProperties")
@@ -61,9 +94,9 @@ pub fn launch(config: &Config, version: &Version) -> Result<(), McError> {
         .arg("--accessToken")
         .arg("0")
         .arg("--userType")
-        .arg("legacy")
-        .args(&config.jvm_args)
-        .status()?;
+        .arg("legacy"); // legacy dla starych kont, można później zmienić
+
+    let status = cmd.status()?;
 
     if !status.success() {
         return Err(McError::Process("Minecraft exited with error".into()));
@@ -71,3 +104,25 @@ pub fn launch(config: &Config, version: &Version) -> Result<(), McError> {
 
     Ok(())
 }
+
+/// Sprawdza reguły bibliotek tak jak robi Mojang
+fn library_allowed(lib: &Library) -> bool {
+    let rules = match &lib.rules {
+        | Some(r) => r,
+        | None => return true,
+    };
+
+    let mut allowed = false;
+
+    for rule in rules {
+        let os_match = match &rule.os {
+            | Some(os) => os.name == "linux",
+            | None => true,
+        };
+        if os_match {
+            allowed = rule.action == "allow";
+        }
+    }
+
+    allowed
+}
diff --git a/src/minecraft/manifests.rs b/src/minecraft/manifests.rs
index 3cc59af..8bdec26 100644
--- a/src/minecraft/manifests.rs
+++ b/src/minecraft/manifests.rs
@@ -1,4 +1,7 @@
 #![allow(dead_code)]
+
+use std::collections::HashMap;
+
 use reqwest;
 use serde::Deserialize;
 
@@ -13,6 +16,17 @@ pub struct Version {
 
     pub downloads: Downloads,
     pub libraries: Vec<Library>,
+
+    #[serde(rename = "assetIndex")]
+    pub asset_index: Option<AssetIndex>,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct AssetIndex {
+    pub id: String,
+    pub sha1: String,
+    pub size: u64,
+    pub url: String,
 }
 
 #[derive(Debug, Deserialize)]
@@ -29,12 +43,22 @@ pub struct DownloadInfo {
 
 #[derive(Debug, Deserialize)]
 pub struct Library {
+    pub name: Option<String>,
     pub downloads: LibraryDownloads,
+
+    #[serde(default)]
+    pub natives: Option<HashMap<String, String>>,
+
+    #[serde(default)]
+    pub rules: Option<Vec<Rule>>,
 }
 
 #[derive(Debug, Deserialize)]
 pub struct LibraryDownloads {
     pub artifact: Option<LibraryArtifact>,
+
+    #[serde(default)]
+    pub classifiers: Option<HashMap<String, LibraryArtifact>>,
 }
 
 #[derive(Debug, Deserialize)]
@@ -45,7 +69,20 @@ pub struct LibraryArtifact {
     pub size: u64,
 }
 
-pub async fn load_version(cfg: &crate::config::Config) -> Result<Version, McError> {
+#[derive(Debug, Deserialize)]
+pub struct Rule {
+    pub action: String,
+    pub os: Option<OsRule>,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct OsRule {
+    pub name: String,
+}
+
+pub async fn load_version(
+    cfg: &crate::config::Config,
+) -> Result<Version, McError> {
     let manifest_text = reqwest::get(VERSION_MANIFEST_URL)
         .await?
         .text()
@@ -67,7 +104,9 @@ pub async fn load_version(cfg: &crate::config::Config) -> Result<Version, McErro
     let version_entry = versions
         .iter()
         .find(|v| v["id"].as_str() == Some(&version_id))
-        .ok_or_else(|| McError::Config(format!("version '{}' not found", version_id)))?;
+        .ok_or_else(|| {
+            McError::Config(format!("version '{}' not found", version_id))
+        })?;
 
     let url = version_entry["url"]
         .as_str()
diff --git a/src/minecraft/mod.rs b/src/minecraft/mod.rs
index f1ce1f0..6dea71d 100644
--- a/src/minecraft/mod.rs
+++ b/src/minecraft/mod.rs
@@ -1,3 +1,18 @@
+//! Minecraft module for the DML launcher.
+//!
+//! This module provides the core functionality for interacting with
+//! Minecraft game files, including downloading assets, extracting
+//! game JARs, managing libraries, and launching the game.
+//!
+//! # Submodules
+//! - `downloads`: Async functions for downloading game files and assets.
+//! - `extraction`: Functions for extracting ZIP/JAR files to the correct
+//!   locations.
+//! - `launcher`: Functions to launch the Minecraft process with the proper
+//!   arguments.
+//! - `manifests`: Structures representing Minecraft version manifests,
+//!   libraries, and rules.
+
 pub mod downloads;
 pub mod extraction;
 pub mod launcher;
diff --git a/src/platform/mod.rs b/src/platform/mod.rs
index 8118b29..24619ff 100644
--- a/src/platform/mod.rs
+++ b/src/platform/mod.rs
@@ -1 +1,11 @@
+//! Platform-specific helpers for the DML launcher.
+//!
+//! This module provides utilities for handling file paths and directories
+//! across operating systems. It includes functions to get standard locations
+//! for Minecraft game data, assets, libraries, and version directories.
+//!
+//! # Submodules
+//! - `paths`: Functions to construct paths for Minecraft data, assets,
+//!   libraries, and versions.
+
 pub mod paths;
diff --git a/src/platform/paths.rs b/src/platform/paths.rs
index 47aae9a..b430f09 100644
--- a/src/platform/paths.rs
+++ b/src/platform/paths.rs
@@ -1,48 +1,44 @@
-use std::{fs, path::PathBuf};
-
-use directories::ProjectDirs;
+use std::{fs::create_dir_all, path::PathBuf};
 
 use crate::{config::Config, errors::McError};
 
-fn project_dirs() -> ProjectDirs {
-    ProjectDirs::from("com", "dml", "dml").expect("failed to determine project directories")
+/// ~/.local/share/dml/minecraft
+pub fn minecraft_root(cfg: &Config) -> PathBuf {
+    cfg.data_dir.join("minecraft")
 }
 
-/// Root Minecraft directory
-pub fn minecraft_root(_cfg: &Config) -> PathBuf { project_dirs().data_dir().join("minecraft") }
-
-/* ---------------- setup ---------------- */
+pub fn assets_dir(cfg: &Config) -> PathBuf {
+    minecraft_root(cfg).join("assets")
+}
 
+pub fn game_dir(cfg: &Config) -> PathBuf { minecraft_root(cfg) }
 pub fn ensure_dirs(cfg: &Config) -> Result<(), McError> {
     let root = minecraft_root(cfg);
-
-    fs::create_dir_all(root.join("versions"))?;
-    fs::create_dir_all(root.join("libraries"))?;
-    fs::create_dir_all(root.join("assets"))?;
+    create_dir_all(&root)?;
+    create_dir_all(root.join("versions"))?;
+    create_dir_all(root.join("libraries"))?;
+    create_dir_all(assets_dir(cfg))?;
+    create_dir_all(assets_dir(cfg).join("indexes"))?;
+    create_dir_all(assets_dir(cfg).join("objects"))?;
+    create_dir_all(root.join("saves"))?;
 
     Ok(())
 }
 
-/* ---------------- versions ---------------- */
-
 pub fn version_dir(cfg: &Config, version: &str) -> PathBuf {
     minecraft_root(cfg).join("versions").join(version)
 }
 
 pub fn client_jar(cfg: &Config, version: &str) -> Result<PathBuf, McError> {
-    Ok(version_dir(cfg, version).join(format!("{}.jar", version)))
+    Ok(version_dir(cfg, version).join(format!("{version}.jar")))
 }
 
-/* ---------------- libraries ---------------- */
-
 pub fn library_file(cfg: &Config, rel_path: &str) -> Result<PathBuf, McError> {
     Ok(minecraft_root(cfg)
         .join("libraries")
         .join(rel_path))
 }
 
-/* ---------------- natives ---------------- */
-
 pub fn natives_dir(cfg: &Config, version: &str) -> PathBuf {
     version_dir(cfg, version).join("natives")
 }
diff --git a/src/util/fs.rs b/src/util/fs.rs
index b86c0d7..8ecd0d0 100644
--- a/src/util/fs.rs
+++ b/src/util/fs.rs
@@ -2,11 +2,13 @@
 
 use std::path::Path;
 
+use tokio::fs::remove_file;
+
 use crate::errors::McError;
 
 pub async fn remove_if_exists(path: &Path) -> Result<(), McError> {
     if path.exists() {
-        tokio::fs::remove_file(path).await?;
+        remove_file(path).await?;
     }
     Ok(())
 }
diff --git a/src/util/mod.rs b/src/util/mod.rs
index 8176b9b..b8531c6 100644
--- a/src/util/mod.rs
+++ b/src/util/mod.rs
@@ -1,2 +1,14 @@
+//! Utility module for the DML launcher.
+//!
+//! This module contains general-purpose helper functions used throughout
+//! the project. It is designed to provide reusable functionality without
+//! being specific to Minecraft or configuration.
+//!
+//! # Submodules
+//! - `fs`: File system utilities such as safe file creation, reading, and
+//!   writing.
+//! - `sha1`: Functions to compute SHA-1 hashes for files and data integrity
+//!   checks.
+
 pub mod fs;
 pub mod sha1;
diff --git a/src/util/sha1.rs b/src/util/sha1.rs
index c5f1021..6684963 100644
--- a/src/util/sha1.rs
+++ b/src/util/sha1.rs
@@ -3,11 +3,12 @@
 use std::path::Path;
 
 use sha1::{Digest, Sha1};
+use tokio::fs::read;
 
 use crate::errors::McError;
 
 pub async fn sha1_hex(path: &Path) -> Result<String, McError> {
-    let data = tokio::fs::read(path).await?;
+    let data = read(path).await?;
     let mut hasher = Sha1::new();
     hasher.update(&data);
     Ok(format!("{:x}", hasher.finalize()))