#!/usr/bin/env bash

# -x echos commands.
# -e exits if a command returns an error.
set -x -e

if [ ! -f make.bash ]; then
  echo "make.bash must be run from $GOPATH/src/github.com/Psiphon-Labs/psiphon-tunnel-core/ClientLibrary"
  exit 1
fi

# This script takes an optional second argument: 'private', if private plugins should
# be used. It should be omitted if private plugins are not desired.
if [[ $2 == "private" ]]; then
  FORCE_PRIVATE_PLUGINS=true
  echo "TRUE"
else
  FORCE_PRIVATE_PLUGINS=false
  echo "FALSE"
fi

# BUILD_TAGS needs to be outside of prepare_build because it determines what's fetched by go-get.

PRIVATE_PLUGINS_TAG=""
if [[ ${FORCE_PRIVATE_PLUGINS} == true ]]; then PRIVATE_PLUGINS_TAG="PRIVATE_PLUGINS"; fi
BUILD_TAGS="${PRIVATE_PLUGINS_TAG}"
WINDOWS_BUILD_TAGS="${BUILD_TAGS}"
LINUX_BUILD_TAGS="${BUILD_TAGS}"
ANDROID_BUILD_TAGS="${BUILD_TAGS}"

BUILD_DIR=build

if [ ! -d ${BUILD_DIR} ]; then
  mkdir ${BUILD_DIR}
fi


prepare_build () {

  BUILDDATE=$(date --iso-8601=seconds)
  BUILDREPO=$(git config --get remote.origin.url)
  BUILDREV=$(git rev-parse --short HEAD)
  GOVERSION=$(go version | perl -ne '/go version (.*?) / && print $1')

  # - starts the string with a `{`
  # - uses the `go list` command and passes it a template string (using the Go template syntax) saying I want all the dependencies of the package in the current directory, printing 1/line via printf
  # - pipes to `xargs` to run a command on each line output from the first command
  #  - uses `go list` with a template string to print the "Import Path" (from just below `$GOPATH/src`) if the package is not part of the standard library
  # - pipes to `xargs` again, specifiying `pkg` as the placeholder name for each item being operated on (which is the list of non standard library import paths from the previous step)
  #  - `xargs` runs a bash script (via `-c`) which changes to each import path in sequence, then echoes out `"<import path>":"<subshell output of getting the short git revision>",`
  # - this leaves a trailing `,` at the end, and no close to the JSON object, so simply `sed` replace the comma before the end of the line with `}` and you now have valid JSON
  DEPENDENCIES=$(echo -n "{" && go list -tags "$1" -f '{{range $dep := .Deps}}{{printf "%s\n" $dep}}{{end}}' | xargs go list -f '{{if not .Standard}}{{.ImportPath}}{{end}}' | xargs -I pkg bash -c 'cd $GOPATH/src/pkg && echo -n "\"pkg\":\"$(git rev-parse --short HEAD)\","' | sed 's/,$/}/')

  LDFLAGS="\
  -X github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common.buildDate=$BUILDDATE \
  -X github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common.buildRepo=$BUILDREPO \
  -X github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common.buildRev=$BUILDREV \
  -X github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common.goVersion=$GOVERSION \
  -X github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common.dependencies=$DEPENDENCIES \
  "

  echo "Variables for ldflags:"
  echo " Build date: ${BUILDDATE}"
  echo " Build repo: ${BUILDREPO}"
  echo " Build revision: ${BUILDREV}"
  echo " Go version: ${GOVERSION}"
  echo " Dependencies: ${DEPENDENCIES}"
  echo ""

}


build_for_android () {

  TARGET_OS=android
  OUTPUT_DIR="${BUILD_DIR}/${TARGET_OS}"

  echo "...Getting project dependencies (via go get) for Android."
  GOOS=windows go get -d -v -tags "$ANDROID_BUILD_TAGS" ./...
  prepare_build "$ANDROID_BUILD_TAGS"
  if [ $? != 0 ]; then
    echo "....'go get' failed, exiting"
    exit $?
  fi

  TARGET_NDK=android-ndk-r17b
  curl https://dl.google.com/android/repository/${TARGET_NDK}-linux-x86_64.zip -o ~/android-ndk.zip
  unzip ~/android-ndk.zip -d ~/

  NDK_TOOLCHAIN_DIR=~/android-ndk-toolchain
  mkdir -p ${NDK_TOOLCHAIN_DIR}

  TARGET_ARCH=arm
  ARMV=7
  ~/${TARGET_NDK}/build/tools/make_standalone_toolchain.py --arch "${TARGET_ARCH}" --install-dir "${NDK_TOOLCHAIN_DIR}/${TARGET_ARCH}"

  CC="${NDK_TOOLCHAIN_DIR}/${TARGET_ARCH}/bin/arm-linux-androideabi-clang" \
  CXX="${NDK_TOOLCHAIN_DIR}/${TARGET_ARCH}/bin/arm-linux-androideabi-clang++" \
  GOARM=${ARMV} \
  GOOS=${TARGET_OS} GOARCH=${TARGET_ARCH} go build -buildmode=c-shared -ldflags "$LDFLAGS" -tags "$ANDROID_BUILD_TAGS" -o "${OUTPUT_DIR}/PsiphonTunnel-${TARGET_OS}-${TARGET_ARCH}${ARMV}.so" PsiphonTunnel.go


  TARGET_ARCH=arm64
  ~/${TARGET_NDK}/build/tools/make_standalone_toolchain.py --arch "${TARGET_ARCH}" --install-dir "${NDK_TOOLCHAIN_DIR}/${TARGET_ARCH}"

  CC="${NDK_TOOLCHAIN_DIR}/${TARGET_ARCH}/bin/aarch64-linux-android-clang" \
  CXX="${NDK_TOOLCHAIN_DIR}/${TARGET_ARCH}/bin/aarch64-linux-android-clang++" \
  GOOS=${TARGET_OS} GOARCH=${TARGET_ARCH} go build -buildmode=c-shared -ldflags "$LDFLAGS" -tags "$ANDROID_BUILD_TAGS" -o "${OUTPUT_DIR}/PsiphonTunnel-${TARGET_OS}-${TARGET_ARCH}.so" PsiphonTunnel.go

}


build_for_linux () {

	TARGET_OS=linux
  OUTPUT_DIR="${BUILD_DIR}/${TARGET_OS}"

  echo "...Getting project dependencies (via go get) for Linux."
  GOOS=linux go get -d -v -tags "$LINUX_BUILD_TAGS" ./...
  prepare_build "$LINUX_BUILD_TAGS"
  if [ $? != 0 ]; then
    echo "....'go get' failed, exiting"
    exit $?
  fi

	TARGET_ARCH=386
	# TODO: is "CFLAGS=-m32" required?
	CFLAGS=-m32 \
	GOOS=${TARGET_OS} GOARCH=${TARGET_ARCH} go build -buildmode=c-shared -ldflags "$LDFLAGS" -tags "$LINUX_BUILD_TAGS" -o "${OUTPUT_DIR}/PsiphonTunnel-${TARGET_OS}-${TARGET_ARCH}.so" PsiphonTunnel.go


	TARGET_ARCH=amd64
	GOOS=linux GOARCH=${TARGET_ARCH} go build -buildmode=c-shared -ldflags "$LDFLAGS" -tags "$LINUX_BUILD_TAGS" -o "${OUTPUT_DIR}/PsiphonTunnel-${TARGET_OS}-${TARGET_ARCH}.so" PsiphonTunnel.go

}


build_for_windows () {

  TARGET_OS=windows
  OUTPUT_DIR="${BUILD_DIR}/${TARGET_OS}"

  echo "...Getting project dependencies (via go get) for Windows."
  GOOS=windows go get -d -v -tags "$WINDOWS_BUILD_TAGS" ./...
  prepare_build "$WINDOWS_BUILD_TAGS"
  if [ $? != 0 ]; then
    echo "....'go get' failed, exiting"
    exit $?
  fi

  TARGET_ARCH=386

  CGO_ENABLED=1 \
  CGO_LDFLAGS="-L /usr/i686-w64-mingw32/lib/ -lwsock32 -lcrypt32 -lgdi32" \
  CC=/usr/bin/i686-w64-mingw32-gcc \
  GOOS=${TARGET_OS} GOARCH=${TARGET_ARCH} go build -buildmode=c-shared -ldflags "$LDFLAGS" -tags "$WINDOWS_BUILD_TAGS" -o "${OUTPUT_DIR}/PsiphonTunnel-${TARGET_OS}-${TARGET_ARCH}.dll" PsiphonTunnel.go

  TARGET_ARCH=amd64

  CGO_ENABLED=1 \
  CGO_LDFLAGS="-L /usr/x86_64-w64-mingw32/lib/ -lwsock32 -lcrypt32 -lgdi32" \
  CC=/usr/bin/x86_64-w64-mingw32-gcc \
  GOOS=${TARGET_OS} GOARCH=${TARGET_ARCH} go build -buildmode=c-shared -ldflags "$LDFLAGS" -tags "$WINDOWS_BUILD_TAGS" -o "${OUTPUT_DIR}/PsiphonTunnel-${TARGET_OS}-${TARGET_ARCH}.dll" PsiphonTunnel.go

}


build_for_ios () {

  echo "To build for iOS please use build-darwin.sh"

}


build_for_macos () {

  echo "To build for macos please use build-darwin.sh"

}


TARGET=$1
case $TARGET in
  windows)
    echo "..Building for Windows"
    build_for_windows $2
    exit $?

    ;;
  linux)
    echo "..Building for Linux"
    build_for_linux $2
    exit $?

    ;;
  macos)
    echo "..Building for MacOS"
    build_for_macos
    exit $?

    ;;
  android)
    echo "..Building for Android"
    build_for_android
    exit $?

    ;;
  ios)
    echo "..Building for iOS"
    build_for_ios
    exit $?

    ;;
  all)
    echo "..Building all"
    build_for_windows $2
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_linux $2
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_macos
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_android
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_ios
    if [ $? != 0 ]; then
      exit $?
    fi

    ;;
  *)
    echo "..No selection made, building all"
    build_for_windows $2
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_linux $2
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_macos
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_android
    if [ $? != 0 ]; then
      exit $?
    fi

    build_for_ios
    if [ $? != 0 ]; then
      exit $?
    fi

    ;;

esac

echo "BUILD DONE"