feat: simple musicDB for title

sdgb-api/Cargo.toml

@@ -43,3 +43,4 @@ bincode = { version = "2.0.1", optional = true }
 
 # magic macro
 crabtime = { git = "https://github.com/wdanilo/crabtime.git", rev = "2ed856f5" }
+rustc-hash = "2.1.1"

sdgb-api/src/helper/mod.rs

@@ -10,6 +10,5 @@ pub fn level_name(level: u32) -> &'static str {
     }
 }
 
-// TODO: MusicDB lazy load
-// struct MusicDB;
-// static MUSIC_DB: LazyLock<MusicDB> = LazyLock::new(|| unimplemented!());
+mod music_db;
+pub use music_db::{MUSIC_DB, MusicInfo,};

sdgb-api/src/helper/music_db/mod.rs

@@ -0,0 +1,32 @@
+use std::{fs::OpenOptions, sync::LazyLock};
+
+use rustc_hash::FxHashMap;
+use serde::{Deserialize, Serialize};
+use spdlog::{info, warn};
+
+#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct MusicInfo {
+    pub id: u32,
+    pub name: String,
+    pub version: i64,
+}
+
+type MusicDB = FxHashMap<u32, MusicInfo>;
+
+pub static MUSIC_DB: LazyLock<Option<MusicDB>> = LazyLock::new(|| {
+    info!("loading musicDB...");
+
+    let json = OpenOptions::new()
+        .read(true)
+        .create(false)
+        .open("musicDB.json")
+        .inspect_err(|e| warn!("failed to load musicDB: {e}"))
+        .ok()?;
+
+    let db: Vec<MusicInfo> = serde_json::from_reader(json)
+        .inspect_err(|e| warn!("failed to load musicDB: {e}"))
+        .ok()?;
+
+    Some(db.into_iter().map(|entry| (entry.id, entry)).collect())
+});

sdgb-api/src/title/model/get_user_rating_api/mod.rs

@@ -3,6 +3,7 @@ use std::fmt::Display;
 use serde::Deserialize;
 use serde::Serialize;
 
+use crate::helper::MUSIC_DB;
 use crate::helper::level_name;
 
 #[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
@@ -109,6 +110,10 @@ impl Display for GetUserRatingApiResp {
 impl Display for MusicRating {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         f.write_fmt(format_args!("歌曲ID: \t{}\n", self.music_id))?;
+        if let Some(info) = MUSIC_DB.as_ref().map(|db| db.get(&self.music_id)).flatten() {
+            let title = &info.name;
+            f.write_fmt(format_args!("曲目标题: \t{title}\n"))?;
+        }
         f.write_fmt(format_args!(
             "谱面版本: \t{}\n",
             match (self.music_id / 10000) % 10 {