2 files changed, 47 insertions, 3 deletions
diff --git a/bundle/src-tauri/src/compiler.rs b/bundle/src-tauri/src/compiler.rs
new file mode 100644
index 0000000..275a707
--- /dev/null
+++ b/bundle/src-tauri/src/compiler.rs
@@ -0,0 +1,41 @@
+use std::path::PathBuf;
+
+// Keep startup failures available to the UI, including an unwritable working directory.
+pub struct Compiler(pub Result<PathBuf, String>);
+
+impl Compiler {
+    pub fn load() -> Self {
+        Self(executable().map_err(|error| format!("Cannot load compiler: {error}")))
+    }
+}
+
+#[cfg(not(windows))]
+fn executable() -> std::io::Result<PathBuf> {
+    Ok(std::env::current_exe()?.with_file_name("cpsc"))
+}
+
+#[cfg(windows)]
+fn executable() -> std::io::Result<PathBuf> {
+    use std::{
+        fs::{self, File},
+        io,
+    };
+
+    let directory = std::env::current_dir()?;
+    let destination = directory.join("cpsc.exe");
+    let staged = directory.join(format!(".cpsc-{}.tmp", std::process::id()));
+    let result = (|| {
+        let mut compressed = flate2::read::GzDecoder::new(
+            &include_bytes!(concat!(env!("CARGO_MANIFEST_DIR"), "/binaries/cpsc.exe.gz"))[..],
+        );
+        let mut file = File::create(&staged)?;
+        io::copy(&mut compressed, &mut file)?;
+        drop(file);
+        fs::rename(&staged, &destination)?;
+        Ok(destination)
+    })();
+    if result.is_err() {
+        let _ = fs::remove_file(staged);
+    }
+    result
+}
diff --git a/bundle/src-tauri/src/main.rs b/bundle/src-tauri/src/main.rs
index 96f040c..07f25b3 100644
--- a/bundle/src-tauri/src/main.rs
+++ b/bundle/src-tauri/src/main.rs
@@ -1,6 +1,8 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
 
+mod compiler;
 mod runner;
+use compiler::Compiler;
 use runner::{OutputEvent, Runner};
 use tauri::{ipc::Channel, Manager, State};
 
@@ -20,10 +22,9 @@ async fn run_file(
     input: String,
     output: Channel<OutputEvent>,
     runner: State<'_, Runner>,
+    compiler: State<'_, Compiler>,
 ) -> Result<(), String> {
-    let executable = std::env::current_exe()
-        .map_err(|error| error.to_string())?
-        .with_file_name(if cfg!(windows) { "cpsc.exe" } else { "cpsc" });
+    let executable = compiler.inner().0.clone()?;
     let result = runner
         .run(executable, path.into(), input, |stream, bytes| {
             let _ = output.send(OutputEvent::Data {
@@ -47,9 +48,11 @@ async fn stop_run(runner: State<'_, Runner>) -> Result<(), String> {
 }
 
 fn main() {
+    let compiler = Compiler::load();
     tauri::Builder::default()
         .plugin(tauri_plugin_dialog::init())
         .manage(Runner::default())
+        .manage(compiler)
         .invoke_handler(tauri::generate_handler![
             read_file, write_file, run_file, stop_run
         ])