#!/bin/bash
# Copyright 2020 gRPC authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

set -eu -o pipefail

WORKDIR=$(mktemp -d)

function finish {
  rm -rf "$WORKDIR"
}
trap finish EXIT

export GOBIN=${WORKDIR}/bin
export PATH=${GOBIN}:${PATH}
mkdir -p ${GOBIN}

echo "remove existing generated files"
# grpc_testingv3/testv3.pb.go is not re-generated because it was
# intentionally generated by an older version of protoc-gen-go.
rm -f $(find . -name '*.pb.go' | grep -v 'grpc_testingv3/testv3.pb.go')

echo "go install github.com/golang/protobuf/protoc-gen-go"
(cd test/tools && go install github.com/golang/protobuf/protoc-gen-go)

echo "go install cmd/protoc-gen-go-grpc"
(cd cmd/protoc-gen-go-grpc && go install .)

echo "git clone https://github.com/grpc/grpc-proto"
git clone --quiet https://github.com/grpc/grpc-proto ${WORKDIR}/grpc-proto

# Pull in code.proto as a proto dependency
mkdir -p ${WORKDIR}/googleapis/google/rpc
echo "curl https://raw.githubusercontent.com/googleapis/googleapis/master/google/rpc/code.proto"
curl --silent https://raw.githubusercontent.com/googleapis/googleapis/master/google/rpc/code.proto > ${WORKDIR}/googleapis/google/rpc/code.proto

# Pull in the following repos to build the MeshCA config proto.
ENVOY_API_REPOS=(
  "https://github.com/envoyproxy/data-plane-api"
  "https://github.com/cncf/udpa"
  "https://github.com/envoyproxy/protoc-gen-validate"
)
for repo in ${ENVOY_API_REPOS[@]}; do
  dirname=$(basename ${repo})
  mkdir -p ${WORKDIR}/${dirname}
  echo "git clone ${repo}"
  git clone --quiet ${repo} ${WORKDIR}/${dirname}
done

# Pull in the MeshCA service proto.
mkdir -p ${WORKDIR}/istio/istio/google/security/meshca/v1
echo "curl https://raw.githubusercontent.com/istio/istio/master/security/proto/providers/google/meshca.proto"
curl --silent https://raw.githubusercontent.com/istio/istio/master/security/proto/providers/google/meshca.proto > ${WORKDIR}/istio/istio/google/security/meshca/v1/meshca.proto

mkdir -p ${WORKDIR}/out

# Generates sources without the embed requirement
LEGACY_SOURCES=(
  ${WORKDIR}/grpc-proto/grpc/binlog/v1/binarylog.proto
  ${WORKDIR}/grpc-proto/grpc/channelz/v1/channelz.proto
  ${WORKDIR}/grpc-proto/grpc/health/v1/health.proto
  ${WORKDIR}/grpc-proto/grpc/lb/v1/load_balancer.proto
  profiling/proto/service.proto
  reflection/grpc_reflection_v1alpha/reflection.proto
)

# Generates only the new gRPC Service symbols
SOURCES=(
  $(git ls-files --exclude-standard --cached --others "*.proto" | grep -v '^\(profiling/proto/service.proto\|reflection/grpc_reflection_v1alpha/reflection.proto\)$')
  ${WORKDIR}/grpc-proto/grpc/gcp/altscontext.proto
  ${WORKDIR}/grpc-proto/grpc/gcp/handshaker.proto
  ${WORKDIR}/grpc-proto/grpc/gcp/transport_security_common.proto
  ${WORKDIR}/grpc-proto/grpc/lookup/v1/rls.proto
  ${WORKDIR}/grpc-proto/grpc/lookup/v1/rls_config.proto
  ${WORKDIR}/grpc-proto/grpc/service_config/service_config.proto
  ${WORKDIR}/grpc-proto/grpc/tls/provider/meshca/experimental/config.proto
  ${WORKDIR}/istio/istio/google/security/meshca/v1/meshca.proto
)

# These options of the form 'Mfoo.proto=bar' instruct the codegen to use an
# import path of 'bar' in the generated code when 'foo.proto' is imported in
# one of the sources.
OPTS=Mgrpc/service_config/service_config.proto=/internal/proto/grpc_service_config,\
Menvoy/config/core/v3/config_source.proto=github.com/envoyproxy/go-control-plane/envoy/config/core/v3

for src in ${SOURCES[@]}; do
  echo "protoc ${src}"
  protoc --go_out=${OPTS}:${WORKDIR}/out --go-grpc_out=${OPTS}:${WORKDIR}/out \
    -I"." \
    -I${WORKDIR}/grpc-proto \
    -I${WORKDIR}/googleapis \
    -I${WORKDIR}/data-plane-api \
    -I${WORKDIR}/udpa \
    -I${WORKDIR}/protoc-gen-validate \
    -I${WORKDIR}/istio \
    ${src}
done

for src in ${LEGACY_SOURCES[@]}; do
  echo "protoc ${src}"
  protoc --go_out=${OPTS}:${WORKDIR}/out --go-grpc_out=${OPTS},require_unimplemented_servers=false:${WORKDIR}/out \
    -I"." \
    -I${WORKDIR}/grpc-proto \
    -I${WORKDIR}/googleapis \
    -I${WORKDIR}/data-plane-api \
    -I${WORKDIR}/udpa \
    -I${WORKDIR}/protoc-gen-validate \
    -I${WORKDIR}/istio \
    ${src}
done

# The go_package option in grpc/lookup/v1/rls.proto doesn't match the
# current location. Move it into the right place.
mkdir -p ${WORKDIR}/out/google.golang.org/grpc/balancer/rls/internal/proto/grpc_lookup_v1
mv ${WORKDIR}/out/google.golang.org/grpc/lookup/grpc_lookup_v1/* ${WORKDIR}/out/google.golang.org/grpc/balancer/rls/internal/proto/grpc_lookup_v1

# grpc_testingv3/testv3.pb.go is not re-generated because it was
# intentionally generated by an older version of protoc-gen-go.
rm ${WORKDIR}/out/google.golang.org/grpc/reflection/grpc_testingv3/*.pb.go

# grpc/service_config/service_config.proto does not have a go_package option.
mv ${WORKDIR}/out/grpc/service_config/service_config.pb.go internal/proto/grpc_service_config

# istio/google/security/meshca/v1/meshca.proto does not have a go_package option.
mkdir -p ${WORKDIR}/out/google.golang.org/grpc/credentials/tls/certprovider/meshca/internal/v1/
mv ${WORKDIR}/out/istio/google/security/meshca/v1/* ${WORKDIR}/out/google.golang.org/grpc/credentials/tls/certprovider/meshca/internal/v1/

cp -R ${WORKDIR}/out/google.golang.org/grpc/* .