#!/bin/bash

if [ -z ${ANDROID_NDK_HOME+x} ]; then
  echo "Error: \$ANDROID_NDK_HOME is not defined."
elif [ -z ${OPENSSL_PATH+x} ]; then
    echo "Error: \$OPENSSL_PATH is not defined."
else
  NDK_BIN_PATH="$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin"
  declare -a ABIs=("x86_64" "arm64-v8a" "armeabi-v7a")

  compile_openssl(){
    if [ ! -d "./lib/$1" ]; then
      if [ "$1" = "x86_64" ]; then
        OPENSSL_ARCH="android-x86_64"
      elif [ "$1" = "arm64-v8a" ]; then
        OPENSSL_ARCH="android-arm64"
      elif [ "$1" = "armeabi-v7a" ]; then
        OPENSSL_ARCH="android-arm"
      else
        echo "Invalid ABI: $1"
        exit
      fi

      export CFLAGS=-D__ANDROID_API__=21
      export PATH=$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin:$ANDROID_NDK_HOME/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin:$PATH
      (cd "$OPENSSL_PATH" && if [ -f "Makefile" ]; then make clean; fi && ./Configure $OPENSSL_ARCH -D__ANDROID_API__=21 no-stdio && make build_libs)
      mkdir -p "./lib/$1" && cp "$OPENSSL_PATH/libcrypto.a" "$OPENSSL_PATH/libssl.a" "./lib/$1"
      mkdir -p "./include/$1" && cp -r "$OPENSSL_PATH"/include/* "./include/$1/"
    fi
  }

  compile_for_arch(){
    compile_openssl $1
    MAIN_PACKAGE="main.go"
    if [ "$1" = "x86_64" ]; then
      CFN="x86_64-linux-android21-clang"
    elif [ "$1" = "arm64-v8a" ]; then
      CFN="aarch64-linux-android21-clang"
      export GOARCH=arm64
      export GOARM=7
    elif [ "$1" = "armeabi-v7a" ]; then
      CFN="armv7a-linux-androideabi21-clang"
      export GOARCH=arm
      export GOARM=7
      MAIN_PACKAGE="main32.go"
      #patch arch specific code
      sed "s/C.malloc(C.ulong/C.malloc(C.uint/g" main.go > $MAIN_PACKAGE
      sed -i "s/st.Mtim.Sec/int64(st.Mtim.Sec)/g" $MAIN_PACKAGE
    else
      echo "Invalid ABI: $1"
      exit
    fi

    export CC="$NDK_BIN_PATH/$CFN"
    export CXX="$NDK_BIN_PATH/$CFN++"
    export CGO_ENABLED=1
    export GOOS=android
    export CGO_CFLAGS="-I ${PWD}/include/$1"
    export CGO_LDFLAGS="-Wl,-soname=libgocryptfs.so -L${PWD}/lib/$1"
    go build -o build/$1/libgocryptfs.so -buildmode=c-shared $MAIN_PACKAGE
    if [ $MAIN_PACKAGE = "main32.go" ]; then
      rm $MAIN_PACKAGE
    fi
  }

  if [ "$#" -eq 1 ]; then
    compile_for_arch $1
  else
    for abi in ${ABIs[@]}; do
      echo "Compiling for $abi..."
      compile_for_arch $abi
    done
  fi
  echo "Done."
fi