Add support for mods (Probably)

build.rs

@@ -11,6 +11,6 @@ fn main() {
     }
 
     if !std::fs::exists("webui/index.html").unwrap_or(false) {
-        panic!("Could not compile crate! Missing webui! Did you pull submodules?");
+        panic!("Missing webui! Did you pull submodules?\nRun `git submodule update --init --recursive`");
     }
 }

src/main.rs

@@ -4,6 +4,7 @@ fn main() -> std::io::Result<()> {
     let args = ew::get_args();
     ew::runtime::update_data_path(&args.path);
     ew::runtime::update_masterdata_path(&args.masterdata);
+    ew::runtime::update_mod_paths(&args.mods);
     ew::run_server(false)
 }
 

src/options.rs

@@ -63,7 +63,10 @@ pub struct Args {
     pub image_asset_path: String,
 
     #[arg(long, default_value = "", help = "Optional directory to load asset lists and master data CSVs from at runtime. Layout mirrors the bundled assets (asset_lists/, csv/, csv-en/). Missing files fall back to the internal copies.")]
-    pub masterdata: String
+    pub masterdata: String,
+
+    #[arg(long = "mod", value_name = "DIR", action = clap::ArgAction::Append, help = "Path to a mod directory layered on top of --masterdata + the bundled defaults. May be passed multiple times. Each mod dir mirrors the masterdata layout (asset_lists/, csv/, csv-en/, userdata/) but only needs to include the files it adds rows to. CSV rows merge by primary key (first column), asset_lists entries merge by m_identifier, new_user.json top-level arrays union. Later --mod wins on collisions.")]
+    pub mods: Vec<String>
 }
 
 pub fn get_args() -> Args {

src/router/asset_lists.rs

@@ -1,8 +1,15 @@
 use actix_web::{HttpRequest, web, Responder, HttpResponse};
 use actix_web::http::header::ContentType;
 use jzon::object;
+use lazy_static::lazy_static;
+use std::collections::HashMap;
+use std::sync::Mutex;
 use crate::include_file;
 
+lazy_static! {
+    static ref MERGED_CACHE: Mutex<HashMap<String, String>> = Mutex::new(HashMap::new());
+}
+
 pub fn routes(cfg: &mut web::ServiceConfig) {
     cfg.service(
         web::scope("/assetLists")
@@ -25,18 +32,75 @@ async fn get(_req: HttpRequest) -> impl Responder {
 }
 
 fn load_list(name: &str) -> String {
+    if let Some(cached) = MERGED_CACHE.lock().unwrap().get(name) {
+        return cached.clone();
+    }
     let rel = format!("asset_lists/{}.json", name);
-    if let Some(bytes) = crate::runtime::read_masterdata_file(&rel) {
-        if let Ok(s) = String::from_utf8(bytes) {
-            return s;
+    let base = crate::runtime::read_masterdata_file(&rel)
+        .and_then(|b| String::from_utf8(b).ok())
+        .unwrap_or_else(|| match name {
+            "Bundle" => include_file!("src/router/asset_lists/Bundle.json"),
+            "Movie"  => include_file!("src/router/asset_lists/Movie.json"),
+            "Sound"  => include_file!("src/router/asset_lists/Sound.json"),
+            _ => unreachable!(),
+        });
+
+    let mod_files = crate::runtime::read_mod_files(&rel);
+    let merged = if mod_files.is_empty() {
+        base
+    } else {
+        merge_asset_list(name, base, mod_files)
+    };
+    MERGED_CACHE.lock().unwrap().insert(name.to_string(), merged.clone());
+    merged
+}
+
+fn merge_asset_list(name: &str, base: String, mod_files: Vec<(String, Vec<u8>)>) -> String {
+    let mut root = match jzon::parse(&base) {
+        Ok(v) => v,
+        Err(_) => return base,
+    };
+
+    let mut by_ident: HashMap<String, usize> = HashMap::new();
+    if let jzon::JsonValue::Array(ref arr) = root["m_manifestCollection"] {
+        for (i, e) in arr.iter().enumerate() {
+            let id = e["m_identifier"].to_string();
+            by_ident.insert(id.to_string(), i);
         }
     }
-    match name {
-        "Bundle" => include_file!("src/router/asset_lists/Bundle.json"),
-        "Movie" => include_file!("src/router/asset_lists/Movie.json"),
-        "Sound" => include_file!("src/router/asset_lists/Sound.json"),
-        _ => unreachable!(),
+
+    for (mod_dir, bytes) in mod_files {
+        let Ok(s) = String::from_utf8(bytes) else { continue };
+        let Ok(mod_root) = jzon::parse(&s) else { continue };
+        let mod_entries = match mod_root["m_manifestCollection"] {
+            jzon::JsonValue::Array(ref arr) => arr.clone(),
+            _ => continue,
+        };
+        let mut added = 0usize;
+        let mut replaced = 0usize;
+        for entry in mod_entries {
+            let ident = entry["m_identifier"].as_str().unwrap_or("").to_string();
+            if ident.is_empty() {
+                continue;
+            }
+            if let Some(&idx) = by_ident.get(&ident) {
+                root["m_manifestCollection"][idx] = entry;
+                replaced += 1;
+            } else {
+                let idx = root["m_manifestCollection"].len();
+                let _ = root["m_manifestCollection"].push(entry);
+                by_ident.insert(ident, idx);
+                added += 1;
+            }
+        }
+        if added > 0 || replaced > 0 {
+            println!(
+                "[mod {}] {}.json: +{} new entries, {} replaced",
+                mod_dir, name, added, replaced
+            );
+        }
     }
+    jzon::stringify(root)
 }
 
 async fn supported() -> impl Responder {

src/runtime.rs

@@ -9,6 +9,7 @@ lazy_static! {
     static ref DATAPATH: RwLock<String> = RwLock::new(String::new());
     static ref MASTERDATA_PATH: RwLock<String> = RwLock::new(String::new());
     static ref MASTERDATA_WARNED: Mutex<HashSet<String>> = Mutex::new(HashSet::new());
+    static ref MOD_PATHS: RwLock<Vec<String>> = RwLock::new(Vec::new());
     static ref EASTER: RwLock<bool> = RwLock::new(false);
 }
 
@@ -79,3 +80,39 @@ pub fn set_easter_mode(enabled: bool) {
 pub fn get_easter_mode() -> bool {
     *EASTER.read().unwrap()
 }
+
+pub fn update_mod_paths(paths: &[String]) {
+    let cleaned: Vec<String> = paths.iter()
+        .map(|p| p.trim_end_matches('/').to_string())
+        .filter(|p| !p.is_empty())
+        .filter_map(|p| {
+            if Path::new(&p).is_dir() {
+                Some(p)
+            } else {
+                println!("Couldn't find mod directory {} — skipping", p);
+                None
+            }
+        })
+        .collect();
+    if !cleaned.is_empty() {
+        println!("Loaded {} mod overlay{}", cleaned.len(),
+                 if cleaned.len() == 1 { "" } else { "s" });
+        for p in &cleaned {
+            println!("  mod: {}", p);
+        }
+    }
+    let mut w = MOD_PATHS.write().unwrap();
+    *w = cleaned;
+}
+
+pub fn read_mod_files(rel_path: &str) -> Vec<(String, Vec<u8>)> {
+    let paths = MOD_PATHS.read().unwrap().clone();
+    let mut out = Vec::new();
+    for p in paths {
+        let full = format!("{}/{}", p, rel_path);
+        if let Ok(bytes) = fs::read(&full) {
+            out.push((p, bytes));
+        }
+    }
+    out
+}