initial commit

rust/src/formats/datafile.rs

@@ -0,0 +1,46 @@
+use binrw::{binread, NullString};
+use std::collections::HashMap;
+
+#[binread]
+#[br(little, magic = b"MHJNR")]
+#[derive(Debug)]
+pub struct Datafile {
+    #[br(align_after = 0x20)]
+    pub edition: Edition,
+
+    #[br(temp)]
+    pub count: u32,
+    #[br(align_after = 0x20)]
+    pub unk1: u32,
+
+    #[br(count = count)]
+    pub files: Vec<FileEntry>,
+}
+
+#[binread]
+#[derive(Debug)]
+pub enum Edition {
+    #[br(magic = b"-XS")]
+    Xs,
+    #[br(magic = b"-XXL")]
+    Xxl,
+}
+
+#[derive(Debug)]
+#[binread]
+pub struct FileEntry {
+    #[br(pad_size_to = 0x68)]
+    pub name: NullString,
+    pub pos: u32,
+    #[br(pad_after = 0x10)]
+    pub len: u32,
+}
+
+impl Datafile {
+    pub fn into_index(self) -> HashMap<String, FileEntry> {
+        self.files
+            .into_iter()
+            .map(|entry| (entry.name.to_string(), entry))
+            .collect()
+    }
+}