#!/bin/bash

# Copyright 2014 The Kubernetes 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 -o errexit
set -o nounset
set -o pipefail

KUBE_ROOT=$(dirname "${BASH_SOURCE}")/..
source "${KUBE_ROOT}/hack/lib/init.sh"

kube::golang::verify_go_version

cd "${KUBE_ROOT}"

array_contains () {
    local seeking=$1; shift # shift will iterate through the array
    local in=1 # in holds the exit status for the function
    for element; do
        if [[ "$element" == "$seeking" ]]; then
            in=0 # set in to 0 since we found it
            break
        fi
    done
    return $in
}

# Check that the file is in alphabetical order
linted_file="${KUBE_ROOT}/hack/.linted_packages"
if ! diff -u "${linted_file}" <(LC_ALL=C sort "${linted_file}"); then
	{
		echo
		echo "hack/.linted_packages is not in alphabetical order. Please sort it:"
		echo
		echo "  LC_ALL=C sort -o hack/.linted_packages hack/.linted_packages"
		echo
	} >&2
	false
fi

export IFS=$'\n'
# NOTE: when "go list -e ./..." is run within GOPATH, it turns the k8s.io/kubernetes
# as the prefix, however if we run it outside it returns the full path of the file
# with a leading underscore. We'll need to support both scenarios for all_packages.
all_packages=(
	$(go list -e ./... | egrep -v "/(third_party|vendor|staging/src/k8s.io/client-go/pkg|generated|clientset_generated)" | sed -e 's|^k8s.io/kubernetes/||' -e "s|^_${KUBE_ROOT}/\?||")
)
linted_packages=(
	$(cat $linted_file)
)
unset IFS
linted=()
errors=()
for p in "${all_packages[@]}"; do
	# Run golint on package/*.go file explicitly to validate all go files
	# and not just the ones for the current platform.
	failedLint=$(golint "$p"/*.go)
	if [ "$failedLint" ]; then
		if array_contains "$p" "${linted_packages[@]}"; then
			errors+=( "$failedLint" )
		fi
	else
		array_contains "$p" "${linted_packages[@]}" || linted+=( "$p" )
	fi
done

# Check that all linted_packages actually still exist
gone=()
for p in "${linted_packages[@]}"; do
	array_contains "$p" "${all_packages[@]}" || gone+=( "$p" )
done

# Check to be sure all the packages that should pass lint are.
if [ ${#errors[@]} -eq 0 ]; then
	echo 'Congratulations!  All Go source files have been linted.'
else
	{
		echo "Errors from golint:"
		for err in "${errors[@]}"; do
			echo "$err"
		done
		echo
		echo 'Please fix the above errors. You can test via "golint" and commit the result.'
		echo
	} >&2
	false
fi

# check to make sure all packages that pass lint are in the linted file.
echo
if [ ${#linted[@]} -eq 0 -a ${#gone[@]} -eq 0 ]; then
	echo 'Success! All packages that should pass lint are listed in the linted file.'
else
	{
		if [ ${#gone[@]} -gt 0 ]; then
			echo "Some packages in hack/.linted_packages do not exist anymore. Please remove them"
			echo "from hack/.linted_packages:"
			echo
			for p in "${gone[@]}"; do
				echo "  $p"
			done
			echo
		fi
		if [ ${#linted[@]} -gt 0 ]; then
			echo "Some packages passed golint but are not listed in hack/.linted_packages."
			echo "Please add them in alphabetical order:"
			echo
			for p in "${linted[@]}"; do
				echo "  echo $p >> hack/.linted_packages"
			done
			echo "  LC_ALL=C sort -o hack/.linted_packages hack/.linted_packages"
			echo
		fi
		echo 'You can test via this script and commit the result.'
		echo
	} >&2
	false
fi