started the level.dat file creation and completion... I may need to continue the code of level.rs and make an update function to level.dat

src/level.rs

@@ -0,0 +1,80 @@
+use std::fs::File;
+
+use nbt::{Tag, write_nbt};
+
+pub fn create_nbt(
+    name: String,
+    seed: i64,
+    is_hardcore: bool,
+    structures: bool,
+    raining: bool,
+    thundering: bool,
+    game_type: i32,
+    generator_version: i32,
+    raintime: i32,
+    spawnx: i32,
+    spawny: i32,
+    spawnz: i32,
+    thundertime: i32,
+    version: i32,
+    last_played: i64,
+    disk_size: i64,
+    time: i64,
+    generator_name: String,
+    level_name: String,
+    path: String,
+) -> std::io::Result<()> {
+    let mut root = Tag::new_compound(name);
+    root.insert("RandomSeed".to_string(), Tag::new_long("RandomSeed", seed));
+    root.insert(
+        "hardcore".to_string(),
+        Tag::new_byte("hardcore", i8::from(is_hardcore)),
+    );
+    root.insert(
+        "MapFeatures".to_string(),
+        Tag::new_byte("MapFeatures", i8::from(structures)),
+    );
+    root.insert(
+        "raining".to_string(),
+        Tag::new_byte("raining", i8::from(raining)),
+    );
+    root.insert(
+        "thundering".to_string(),
+        Tag::new_byte("thundering", i8::from(thundering)),
+    );
+    root.insert("GameType".to_string(), Tag::new_int("GameType", game_type));
+    root.insert(
+        "GeneratorVersion".to_string(),
+        Tag::new_int("GeneratorVersion", generator_version),
+    );
+    root.insert("RainTime".to_string(), Tag::new_int("RainTime", raintime));
+    root.insert("SpawnX".to_string(), Tag::new_int("SpawnX", spawnx));
+    root.insert("SpawnY".to_string(), Tag::new_int("SpawnY", spawny));
+    root.insert("SpawnZ".to_string(), Tag::new_int("SpawnZ", spawnz));
+    root.insert(
+        "ThunderTime".to_string(),
+        Tag::new_int("ThunderTime", thundertime),
+    );
+    root.insert("Version".to_string(), Tag::new_int("Version", version));
+    root.insert(
+        "LastPlayed".to_string(),
+        Tag::new_long("LastPlayed", last_played),
+    ); // Not sure if I should keep LastPlayed field because of the fact that this isn't for a
+    // client world but for a server world
+    root.insert(
+        "SizeOnDisk".to_string(),
+        Tag::new_long("SizeOnDisk", disk_size),
+    );
+    root.insert("Time".to_string(), Tag::new_long("Time", time));
+    root.insert(
+        "GeneratorName".to_string(),
+        Tag::new_string("GeneratorName", generator_name),
+    );
+    root.insert(
+        "LevelName".to_string(),
+        Tag::new_string("LevelName", level_name),
+    );
+    let file = File::create(path)?;
+    write_nbt(&root, file)?;
+    Ok(())
+}