#!/bin/bash
set -euo pipefail

_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"
_protoc_version="21.7"
_protoc_path="/tmp/pomerium-protoc/protoc-$_protoc_version"
_protoc_3pp_path="/tmp/pomerium-protoc-3pp"
_os="linux"
if [ "$(uname -s)" == "Darwin" ]; then
  _os="osx"
fi

# fetch_zip dir name url
download() {
  local _dir="$1"
  local _name="$2"
  local _url="$3"

  local _dst="$_dir/$_name"
  # if we've already downloaded this zip, just return
  if echo "$_url" | cmp -s - "$_dst/.url"; then
    return
  fi

  echo downloading "$_name"
  local _archive
  _archive="$(mktemp)"
  curl -L -o "$_archive" "$_url"
  rm -rf "$_dst"
  mkdir -p "$_dst"
  tar xzf "$_archive" -C "$_dst" --strip-components=1
  rm "$_archive"
  echo "$_url" >"$_dst/.url"
}

download $_protoc_3pp_path protoc-gen-validate https://github.com/envoyproxy/protoc-gen-validate/tarball/v1.2.1
download $_protoc_3pp_path data-plane-api https://github.com/envoyproxy/data-plane-api/tarball/64bdd0e8c82109ba84569ed2e4eb50170fd9d4fe
download $_protoc_3pp_path udpa https://github.com/cncf/udpa/tarball/c52dc94e7fbe6449d8465faaeda22c76ca62d4ff
download $_protoc_3pp_path xds https://github.com/cncf/xds/tarball/2f005788dc42b92dee41c8ad934450dc4746f027
download $_protoc_3pp_path googleapis https://github.com/googleapis/googleapis/tarball/2fc4ca137765a3003097c58c3f7dab9f4ccfe2b5

mkdir -p "$_protoc_path" "$_protoc_3pp_path"
if [ ! -f "$_protoc_path/bin/protoc" ]; then
  echo "downloading protoc"
  curl -L \
    -o protoc.zip \
    "https://github.com/protocolbuffers/protobuf/releases/download/v$_protoc_version/protoc-$_protoc_version-$_os-x86_64.zip"
  unzip -o -d "$_protoc_path" protoc.zip
  rm protoc.zip
fi

exec "$_protoc_path/bin/protoc" \
  -I "$_protoc_3pp_path/data-plane-api" \
  -I "$_protoc_3pp_path/udpa" \
  -I "$_protoc_3pp_path/xds" \
  -I "$_protoc_3pp_path/protoc-gen-validate" \
  -I "$_protoc_3pp_path/googleapis" \
  --experimental_allow_proto3_optional \
  --plugin="protoc-gen-go=$_dir/protoc-gen-go" \
  --plugin="protoc-gen-go-grpc=$_dir/protoc-gen-go-grpc" \
  --plugin="protoc-gen-grpc-web=$_dir/protoc-gen-grpc-web" \
  --plugin="protoc-gen-validate=$_dir/protoc-gen-validate" \
  "$@"