Add C FFI bindings for library usage

1 files changed, 67 insertions, 11 deletions

diff --git a/build.rs b/build.rs
index d69d05e..4c8cec0 100644
--- a/build.rs
+++ b/build.rs
@@ -1,13 +1,64 @@
+use std::{env, path::PathBuf, str::FromStr};
+
 fn main() {
+    build_butck_ffi();
+
     #[cfg(target_os = "windows")]
     build_win32_gui();
 }
 
+fn build_butck_ffi() {
+    // Check if cbindgen is installed
+    let cbindgen_check = std::process::Command::new("cbindgen")
+        .arg("--version")
+        .output();
+
+    if let Err(e) = cbindgen_check {
+        if e.kind() == std::io::ErrorKind::NotFound {
+            eprintln!("Error: cbindgen is not installed. Please install it with:");
+            eprintln!("    cargo install cbindgen");
+            std::process::exit(1);
+        } else {
+            eprintln!("Error: Failed to check cbindgen installation: {}", e);
+            std::process::exit(1);
+        }
+    }
+
+    let target_dir = get_target_dir();
+
+    // Try to run cbindgen to generate C bindings
+    // > cbindgen --config cbindgen.toml ffi --output ffi/.temp/jvlib.h --quiet
+    let output = std::process::Command::new("cbindgen")
+        .args([
+            "--config",
+            "cbindgen.toml",
+            ".",
+            "--output",
+            &format!("{}/lib_butck.h", target_dir.display()),
+            "--quiet",
+        ])
+        .output();
+
+    match output {
+        Ok(output) if output.status.success() => {
+            // Successfully generated bindings
+        }
+        Ok(_) => {
+            eprintln!("cbindgen failed to generate bindings");
+        }
+        Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
+            eprintln!("cbindgen not found, skipping C binding generation");
+        }
+        Err(e) => {
+            eprintln!("Failed to run cbindgen: {}", e);
+        }
+    }
+}
+
 fn build_win32_gui() {
     use std::fs;
-    use std::path::{Path, PathBuf};
+    use std::path::Path;
     use std::process::Command;
-    use std::str::FromStr;
 
     const EXE_NAME: &str = "butckg.exe";
 
@@ -34,15 +85,7 @@ fn build_win32_gui() {
         .join("gui\\win32\\build\\bin")
         .join(EXE_NAME);
     if exe_path.exists() {
-        let out_dir = std::env::var("OUT_DIR").unwrap();
-        let out_dir_path = PathBuf::from_str(&out_dir).unwrap();
-        let target_dir = out_dir_path
-            .parent()
-            .unwrap()
-            .parent()
-            .unwrap()
-            .parent()
-            .unwrap();
+        let target_dir = get_target_dir();
 
         let dest_path = target_dir.join(EXE_NAME);
         if let Err(e) = fs::copy(&exe_path, &dest_path) {
@@ -55,3 +98,16 @@ fn build_win32_gui() {
         eprintln!("Warning: Executable not found at: {:?}", exe_path);
     }
 }
+
+fn get_target_dir() -> PathBuf {
+    let out_dir = std::env::var("OUT_DIR").unwrap();
+    let out_dir_path = PathBuf::from_str(&out_dir).unwrap();
+    out_dir_path
+        .parent()
+        .unwrap()
+        .parent()
+        .unwrap()
+        .parent()
+        .unwrap()
+        .to_path_buf()
+}