Started working on world

Source/land_of_barl/Cargo.toml

@@ -4,6 +4,10 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+dirs = "6.0.0"
+rmp-serde = "1.3.0"
+serde = { version = "1.0.217", features = ["derive"] }
+thiserror = "2.0.11"
 
 [build-dependencies]
 bindgen = "0.71.1"

Source/land_of_barl/src/lib.rs

@@ -1,3 +1,5 @@
+mod world;
+
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

Source/land_of_barl/src/world/mod.rs

@@ -0,0 +1,67 @@
+use serde::{Deserialize, Serialize};
+use std::fs;
+use std::path::PathBuf;
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error("{0}")]
+    Custom(String),
+    #[error("{0}")]
+    Io(#[from] std::io::Error),
+    #[error("{0}")]
+    RmpEncode(#[from] rmp_serde::encode::Error),
+    #[error("{0}")]
+    RmpDecode(#[from] rmp_serde::decode::Error),
+}
+
+fn get_save_dir() -> Result<PathBuf, Error> {
+    let path = dirs::home_dir()
+        .ok_or(Error::Custom("Failed to get home dir".into()))?
+        .join("land_of_barl");
+    if !path.exists() {
+        std::fs::create_dir_all(&path)?;
+    }
+    Ok(path)
+}
+
+#[derive(Serialize, Deserialize)]
+pub struct SerializedWorld {
+    name: String,
+    day: u32,
+    time: f32,
+}
+
+impl SerializedWorld {
+    pub fn new(name: String) -> Self {
+        Self {
+            name,
+            day: 0,
+            time: 7.0,
+        }
+    }
+
+    pub fn save(&self) -> Result<(), Error> {
+        let path = Self::dir(&self.name)?;
+        if !path.exists() {
+            fs::create_dir_all(&path)?;
+        }
+
+        let content = rmp_serde::to_vec(self)?;
+        fs::write(path.join("world.dat"), content)?;
+
+        Ok(())
+    }
+
+    pub fn load(name: &str) -> Result<Self, Error> {
+        let path = Self::dir(name)?;
+
+        let content = fs::read(path.join("world.dat"))?;
+
+        Ok(rmp_serde::from_slice(&content)?)
+    }
+
+    fn dir(name: &str) -> Result<PathBuf, Error> {
+        Ok(get_save_dir()?.join(name))
+    }
+}