[joox] feat #1: add joox decipher implementation

um_wasm/src/exports/joox.rs

@@ -0,0 +1,29 @@
+use umc_joox::decrypt::JooxDecipher;
+use umc_joox::header::Header;
+use wasm_bindgen::prelude::wasm_bindgen;
+use wasm_bindgen::JsError;
+
+/// Joox file.
+#[wasm_bindgen(js_name=JooxFile)]
+pub struct JsJooxFile(Header);
+
+#[wasm_bindgen(js_class = JooxFile)]
+impl JsJooxFile {
+    /// Initialize header. Header should be 0x0c bytes.
+    pub fn parse(header: &[u8], uuid: String) -> Result<JsJooxFile, JsError> {
+        Ok(JsJooxFile(
+            Header::from_buffer(header, uuid.as_bytes()).map_err(JsError::from)?,
+        ))
+    }
+
+    #[wasm_bindgen(getter, js_name = "bufferLength")]
+    pub fn get_buffer_size(&self) -> usize {
+        self.0.get_audio_block_size()
+    }
+
+    #[wasm_bindgen(js_name = "decrypt")]
+    pub fn decrypt(&self, buffer: &mut [u8]) -> Result<usize, JsError> {
+        let decrypted = self.0.decrypt_audio_block(buffer).map_err(JsError::from)?;
+        Ok(decrypted.len())
+    }
+}

um_wasm/src/exports/mod.rs

@@ -1,4 +1,5 @@
 pub mod audio;
+pub mod joox;
 pub mod kgm;
 pub mod kuwo;
 pub mod ncm;