fix: build on windows

- Added Windows batch file
- Fixed check for empty file on build

Reviewed-on: https://code.gri.mw/GUI/grim/pulls/45

build.rs

@@ -31,7 +31,7 @@ fn main() {
 
     // Build if Webtunnel binary is empty or not exists.
     let empty = match fs::File::open(&webtunnel_file) {
-        Ok(file) => file.metadata().unwrap().len() != 0,
+        Ok(file) => file.metadata().unwrap().len() == 0,
         Err(_) => true
     };
     let build = !exists || empty;
@@ -51,8 +51,12 @@ fn main() {
             "amd64"
         };
         // Run Webtunnel Go build.
-        if let Ok(out) = Command::new("bash")
-            .arg("./scripts/webtunnel.sh")
+        let mut command = if env::consts::OS == "windows" {
+            Command::new("./scripts/webtunnel.bat")
+        } else {
+            Command::new("bash ./scripts/webtunnel.sh")
+        };
+        if let Ok(out) = command
             .arg(go_os)
             .arg(go_arch)
             .arg(webtunnel_file)

scripts/webtunnel.bat

@@ -0,0 +1,70 @@
+@echo off
+setlocal enabledelayedexpansion
+
+:: Change directory to the script's location
+cd /d "%~dp0"
+
+:: Skip if Go not found.
+where go >nul 2>nul
+if %ERRORLEVEL% neq 0 (
+    echo Go could not be found
+    exit /b 0
+)
+
+set "go_os=%~1"
+set "go_arch=%~2"
+set "output_path=%~3"
+
+echo Go build for os: %go_os%, arch: %go_arch%
+
+:: Setup vars for Android.
+if "%go_os%"=="android" (
+
+    :: Setup NDK root path env.
+    if "%ANDROID_NDK_HOME%"=="" (
+        :: Extract ndkVersion from build.gradle
+        :: Equivalent to: cat ../android/app/build.gradle | grep 'ndkVersion' | cut -d ' -f 2
+        for /f "tokens=2 delims='" %%a in ('findstr "ndkVersion" ..\android\app\build.gradle') do (
+            set "NDK_VERSION=%%a"
+        )
+        set "ANDROID_NDK_HOME=%ANDROID_HOME%\ndk\!NDK_VERSION!"
+    )
+
+    :: Setup NDK host path.
+    :: Since this is a Batch script, the host is Windows.
+    set "arch_host=windows-x86_64"
+
+    :: Setup NDK target arch.
+    if "%go_arch%"=="arm64" (
+        set "arch_bin_prefix=aarch64-linux-android"
+    ) else if "%go_arch%"=="arm" (
+        set "arch_bin_prefix=armv7a-linux-androideabi"
+    ) else (
+        set "arch_bin_prefix=x86_64-linux-android"
+    )
+
+    :: Build for current target.
+    set "CGO_ENABLED=1"
+    set "GOOS=%go_os%"
+    set "GOARCH=%go_arch%"
+
+    :: Define CC and CXX paths
+    set "CC=!ANDROID_NDK_HOME!\toolchains\llvm\prebuilt\!arch_host!\bin\!arch_bin_prefix!35-clang"
+    set "CXX=!ANDROID_NDK_HOME!\toolchains\llvm\prebuilt\!arch_host!\bin\!arch_bin_prefix!35-clang++"
+
+    go build -C "../tor/webtunnel" -ldflags="-s -w" -o "%output_path%" code.gri.mw/WEB/webtunnel/main/client
+
+) else (
+    set "extra_flag="
+    if "%go_os%"=="windows" (
+        set "extra_flag=-H=windowsgui"
+    )
+
+    set "GOOS=%go_os%"
+    set "GOARCH=%go_arch%"
+
+    :: Build for non-android targets
+    go build -C "../tor/webtunnel" -ldflags="-s -w !extra_flag!" -o "%output_path%" code.gri.mw/WEB/webtunnel/main/client
+)
+
+endlocal