From 687885b88d6a58fa2f2769ce30f7b445e62d374d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=B2=81=E6=A0=91=E4=BA=BA?= <lu.shuren@um-react.app>
Date: Wed, 18 Sep 2024 23:01:01 +0100
Subject: [PATCH] [wasm/xmly] feat: add wasm glue

---
 Cargo.lock                  |  1 +
 um_wasm/Cargo.toml          |  1 +
 um_wasm/src/exports/mod.rs  |  1 +
 um_wasm/src/exports/xmly.rs | 70 +++++++++++++++++++++++++++++++++++++
 4 files changed, 73 insertions(+)
 create mode 100644 um_wasm/src/exports/xmly.rs

diff --git a/Cargo.lock b/Cargo.lock
index df15492..1302607 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -544,6 +544,7 @@ dependencies = [
  "umc_kuwo",
  "umc_ncm",
  "umc_qmc",
+ "umc_xmly",
  "wasm-bindgen",
  "wasm-bindgen-test",
 ]
diff --git a/um_wasm/Cargo.toml b/um_wasm/Cargo.toml
index 516a116..08def2b 100644
--- a/um_wasm/Cargo.toml
+++ b/um_wasm/Cargo.toml
@@ -28,6 +28,7 @@ umc_kgm = { path = "../um_crypto/kgm" }
 umc_kuwo = { path = "../um_crypto/kuwo" }
 umc_ncm = { path = "../um_crypto/ncm" }
 umc_qmc = { path = "../um_crypto/qmc" }
+umc_xmly = { path = "../um_crypto/xmly" }
 um_audio = { path = "../um_audio" }
 
 [dev-dependencies]
diff --git a/um_wasm/src/exports/mod.rs b/um_wasm/src/exports/mod.rs
index 5b63cdd..e29a581 100644
--- a/um_wasm/src/exports/mod.rs
+++ b/um_wasm/src/exports/mod.rs
@@ -4,3 +4,4 @@ pub mod kgm;
 pub mod kuwo;
 pub mod ncm;
 pub mod qmc;
+pub mod xmly;
diff --git a/um_wasm/src/exports/xmly.rs b/um_wasm/src/exports/xmly.rs
new file mode 100644
index 0000000..cd7b418
--- /dev/null
+++ b/um_wasm/src/exports/xmly.rs
@@ -0,0 +1,70 @@
+use std::convert::TryInto;
+use umc_xmly::android::{decrypt_android, FileType};
+use umc_xmly::pc::Header as PCHeader;
+use umc_xmly::XmlyError;
+use wasm_bindgen::prelude::wasm_bindgen;
+use wasm_bindgen::JsError;
+
+/// Decrypt X2M Header
+#[wasm_bindgen(js_name=decryptX2MHeader)]
+pub fn js_decrypt_x2m_header(buffer: &mut [u8]) -> Result<(), JsError> {
+    decrypt_android(FileType::X2M, buffer.try_into().map_err(JsError::from)?);
+    Ok(())
+}
+
+/// Decrypt X3M Header
+#[wasm_bindgen(js_name=decryptX3MHeader)]
+pub fn js_decrypt_x3m_header(buffer: &mut [u8]) -> Result<(), JsError> {
+    decrypt_android(FileType::X3M, buffer.try_into().map_err(JsError::from)?);
+    Ok(())
+}
+
+/// Ximalaya PC Decipher.
+#[wasm_bindgen(js_name=XmlyPC)]
+pub struct JsXmlyPC(PCHeader);
+
+#[wasm_bindgen(js_class=XmlyPC)]
+impl JsXmlyPC {
+    /// Get required bytes for the header, or throw error if not valid XM file.
+    #[wasm_bindgen(js_name = "getHeaderSize")]
+    pub fn get_header_size(buffer: &[u8]) -> Result<usize, JsError> {
+        let required_len = match PCHeader::from_buffer(buffer) {
+            Ok(hdr) => hdr.data_start_offset,
+            Err(XmlyError::MetadataTooSmall(n)) => n,
+            Err(err) => Err(JsError::from(err))?,
+        };
+
+        Ok(required_len)
+    }
+
+    /// Create a new XmlyPC decipher
+    #[wasm_bindgen(constructor)]
+    pub fn new(header: &[u8]) -> Result<JsXmlyPC, JsError> {
+        let hdr = PCHeader::from_buffer(header)?;
+        Ok(Self(hdr))
+    }
+
+    /// Get the first few bytes of the header.
+    #[wasm_bindgen(getter, js_name=audioHeader)]
+    pub fn get_audio_header(&self) -> Vec<u8> {
+        self.0.copy_m4a_header()
+    }
+
+    /// Get the offset where the encrypted header is
+    #[wasm_bindgen(getter, js_name=encryptedHeaderOffset)]
+    pub fn get_encrypted_header_offset(&self) -> usize {
+        self.0.data_start_offset
+    }
+
+    /// Get the size of encrypted header
+    #[wasm_bindgen(getter, js_name=encryptedHeaderSize)]
+    pub fn get_encrypted_header_len(&self) -> usize {
+        self.0.encrypted_header_size
+    }
+
+    /// Decrypt encrypted header
+    pub fn decrypt(&self, buffer: &mut [u8]) -> Result<usize, JsError> {
+        let size = self.0.decrypt(buffer)?.len();
+        Ok(size)
+    }
+}