#!/bin/bash

set -ex  # Exit on error; debugging enabled.
set -o pipefail  # Fail a pipe if any sub-command fails.

# not makes sure the command passed to it does not exit with a return code of 0.
not() {
  # This is required instead of the earlier (! $COMMAND) because subshells and
  # pipefail don't work the same on Darwin as in Linux.
  ! "$@"
}

die() {
  echo "$@" >&2
  exit 1
}

fail_on_output() {
  tee /dev/stderr | not read
}

# Check to make sure it's safe to modify the user's git repo.
git status --porcelain | fail_on_output

# Undo any edits made by this script.
cleanup() {
  git reset --hard HEAD
}
trap cleanup EXIT

PATH="${HOME}/go/bin:${GOROOT}/bin:${PATH}"

if [[ "$1" = "-install" ]]; then
  # Check for module support
  if go help mod >& /dev/null; then
    # Install the pinned versions as defined in module tools.
    pushd ./test/tools
    go install \
      golang.org/x/lint/golint \
      golang.org/x/tools/cmd/goimports \
      honnef.co/go/tools/cmd/staticcheck \
      github.com/client9/misspell/cmd/misspell
    popd
  else
    # Ye olde `go get` incantation.
    # Note: this gets the latest version of all tools (vs. the pinned versions
    # with Go modules).
    go get -u \
      golang.org/x/lint/golint \
      golang.org/x/tools/cmd/goimports \
      honnef.co/go/tools/cmd/staticcheck \
      github.com/client9/misspell/cmd/misspell
  fi
  if [[ -z "${VET_SKIP_PROTO}" ]]; then
    if [[ "${TRAVIS}" = "true" ]]; then
      PROTOBUF_VERSION=3.14.0
      PROTOC_FILENAME=protoc-${PROTOBUF_VERSION}-linux-x86_64.zip
      pushd /home/travis
      wget https://github.com/google/protobuf/releases/download/v${PROTOBUF_VERSION}/${PROTOC_FILENAME}
      unzip ${PROTOC_FILENAME}
      bin/protoc --version
      popd
    elif [[ "${GITHUB_ACTIONS}" = "true" ]]; then
      PROTOBUF_VERSION=3.14.0
      PROTOC_FILENAME=protoc-${PROTOBUF_VERSION}-linux-x86_64.zip
      pushd /home/runner/go
      wget https://github.com/google/protobuf/releases/download/v${PROTOBUF_VERSION}/${PROTOC_FILENAME}
      unzip ${PROTOC_FILENAME}
      bin/protoc --version
      popd
    elif not which protoc > /dev/null; then
      die "Please install protoc into your path"
    fi
  fi
  exit 0
elif [[ "$#" -ne 0 ]]; then
  die "Unknown argument(s): $*"
fi

# - Ensure all source files contain a copyright message.
not git grep -L "\(Copyright [0-9]\{4,\} gRPC authors\)\|DO NOT EDIT" -- '*.go'

# - Make sure all tests in grpc and grpc/test use leakcheck via Teardown.
not grep 'func Test[^(]' *_test.go
not grep 'func Test[^(]' test/*.go

# - Do not import x/net/context.
not git grep -l 'x/net/context' -- "*.go"

# - Do not import math/rand for real library code.  Use internal/grpcrand for
#   thread safety.
git grep -l '"math/rand"' -- "*.go" 2>&1 | not grep -v '^examples\|^stress\|grpcrand\|^benchmark\|wrr_test'

# - Do not call grpclog directly. Use grpclog.Component instead.
git grep -l 'grpclog.I\|grpclog.W\|grpclog.E\|grpclog.F\|grpclog.V' -- "*.go" | not grep -v '^grpclog/component.go\|^internal/grpctest/tlogger_test.go'

# - Ensure all ptypes proto packages are renamed when importing.
not git grep "\(import \|^\s*\)\"github.com/golang/protobuf/ptypes/" -- "*.go"

# - Ensure all xds proto imports are renamed to *pb or *grpc.
git grep '"github.com/envoyproxy/go-control-plane/envoy' -- '*.go' ':(exclude)*.pb.go' | not grep -v 'pb "\|grpc "'

# - Check imports that are illegal in appengine (until Go 1.11).
# TODO: Remove when we drop Go 1.10 support
go list -f {{.Dir}} ./... | xargs go run test/go_vet/vet.go

# - gofmt, goimports, golint (with exceptions for generated code), go vet.
gofmt -s -d -l . 2>&1 | fail_on_output
goimports -l . 2>&1 | not grep -vE "\.pb\.go"
golint ./... 2>&1 | not grep -vE "\.pb\.go:"
go vet -all ./...

misspell -error .

# - Check that generated proto files are up to date.
if [[ -z "${VET_SKIP_PROTO}" ]]; then
  PATH="/home/travis/bin:${PATH}" make proto && \
    git status --porcelain 2>&1 | fail_on_output || \
    (git status; git --no-pager diff; exit 1)
fi

# - Check that our modules are tidy.
if go help mod >& /dev/null; then
  find . -name 'go.mod' | xargs -IXXX bash -c 'cd $(dirname XXX); go mod tidy'
  git status --porcelain 2>&1 | fail_on_output || \
    (git status; git --no-pager diff; exit 1)
fi

# - Collection of static analysis checks
#
# TODO(dfawley): don't use deprecated functions in examples or first-party
# plugins.
SC_OUT="$(mktemp)"
staticcheck -go 1.9 -checks 'inherit,-ST1015' ./... > "${SC_OUT}" || true
# Error if anything other than deprecation warnings are printed.
not grep -v "is deprecated:.*SA1019" "${SC_OUT}"
# Only ignore the following deprecated types/fields/functions.
not grep -Fv '.CredsBundle
.HeaderMap
.Metadata is deprecated: use Attributes
.NewAddress
.NewServiceConfig
.Type is deprecated: use Attributes
balancer.ErrTransientFailure
balancer.Picker
grpc.CallCustomCodec
grpc.Code
grpc.Compressor
grpc.CustomCodec
grpc.Decompressor
grpc.MaxMsgSize
grpc.MethodConfig
grpc.NewGZIPCompressor
grpc.NewGZIPDecompressor
grpc.RPCCompressor
grpc.RPCDecompressor
grpc.ServiceConfig
grpc.WithBalancerName
grpc.WithCompressor
grpc.WithDecompressor
grpc.WithDialer
grpc.WithMaxMsgSize
grpc.WithServiceConfig
grpc.WithTimeout
http.CloseNotifier
info.SecurityVersion
resolver.Backend
resolver.GRPCLB
extDesc.Filename is deprecated
BuildVersion is deprecated
github.com/golang/protobuf/jsonpb is deprecated
proto is deprecated
xxx_messageInfo_
proto.InternalMessageInfo is deprecated
proto.EnumName is deprecated
proto.ErrInternalBadWireType is deprecated
proto.FileDescriptor is deprecated
proto.Marshaler is deprecated
proto.MessageType is deprecated
proto.RegisterEnum is deprecated
proto.RegisterFile is deprecated
proto.RegisterType is deprecated
proto.RegisterExtension is deprecated
proto.RegisteredExtension is deprecated
proto.RegisteredExtensions is deprecated
proto.RegisterMapType is deprecated
proto.Unmarshaler is deprecated' "${SC_OUT}"

# - special golint on package comments.
lint_package_comment_per_package() {
  # Number of files in this go package.
  fileCount=$(go list -f '{{len .GoFiles}}' $1)
  if [ ${fileCount} -eq 0 ]; then
    return 0
  fi
  # Number of package errors generated by golint.
  lintPackageCommentErrorsCount=$(golint --min_confidence 0 $1 | grep -c "should have a package comment")
  # golint complains about every file that's missing the package comment. If the
  # number of files for this package is greater than the number of errors, there's
  # at least one file with package comment, good. Otherwise, fail.
  if [ ${fileCount} -le ${lintPackageCommentErrorsCount} ]; then
    echo "Package $1 (with ${fileCount} files) is missing package comment"
    return 1
  fi
}
lint_package_comment() {
  set +ex

  count=0
  for i in $(go list ./...); do
    lint_package_comment_per_package "$i"
    ((count += $?))
  done

  set -ex
  return $count
}
lint_package_comment

echo SUCCESS