#!/bin/bash

#
#
# 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.
#

# ---------------------------------------
# versionOk checks version number against required version.
#   ``versionOk 1.2.3 2.0.4.7'' returns false value indicating
#       version you have is not at least version you need
#   if versionOk $haveversion $needversion; then
#      echo "Need at least version $needversion"; exit 1
#   fi
function versionOk() {
	local h=$1 n=$2
	# string compare -- no need to do more if the same
	[[ $h == $n ]] && return 0

	# split into fields
	local have=(${h//\./ })
	local need=(${n//\./ })
	# cmp first entry of each array.  Bail when unequal.
	while [[ -n $have && $have -eq $need ]]; do
		# pop 1st entry from each
		have=("${have[@]:1}")
		need=("${need[@]:1}")
	done
	if [[ ${have:-0} -lt ${need:-0} ]]; then
		return 1
	fi
	return 0
}

# ---------------------------------------
function getRevCount() {
	local buildNum=$(getBuildNumber)
	echo ${buildNum%.*}
}

# ---------------------------------------
function isInGitTree() {
	# ignore output -- use exit status
	git rev-parse --is-inside-work-tree >/dev/null 2>&1
}

# ---------------------------------------
function getBuildNumber() {
	local in_git=$()
	if isInGitTree; then
		local commits=$(git rev-list HEAD 2>/dev/null | wc -l)
		local sha=$(git rev-parse --short=8 HEAD)
		echo "$commits.$sha"
	else
		# Expect it's from the released tarball -- if BUILD_NUMBER file is not present,  abort
		if [[ ! -f $TC_DIR/BUILD_NUMBER ]]; then
			echo "Not in git repository and no BUILD_NUMBER present -- aborting!"
			exit 1
		fi
		grep -v '^#' $TC_DIR/BUILD_NUMBER
	fi
}

# ---------------------------------------
function getVersion() {
	local d="$1"
	local vf="$d/VERSION"
	[ -r $vf ] || { echo "Could not read $vf: $!"; exit 1; }
	cat "$vf"
}

# ---------------------------------------
function getRhelVersion {
        echo el$(rpm -q --qf "%{VERSION}" $(rpm -q --whatprovides redhat-release))
}

# ---------------------------------------
function getCommit() {
	local buildNum=$(getBuildNumber)
	echo ${buildNum%.*}
}

# ---------------------------------------
function checkEnvironment {
	export TC_VERSION=$(getVersion "$TC_DIR")
	export BUILD_NUMBER=$(getBuildNumber)
	export RHEL_VERSION=$(getRhelVersion)
	export WORKSPACE=${WORKSPACE:-$TC_DIR}
	export RPMBUILD="$WORKSPACE/rpmbuild"
	export DIST="$WORKSPACE/dist"

	mkdir -p "$DIST" || { echo "Could not create $DIST: $?"; exit 1; }

	# verify required tools available in path -- extra tools required by subsystem are passed in
	for pgm in git rpmbuild "$@"; do
		type $pgm 2>/dev/null || { echo "$pgm not found in PATH"; }
	done
	# verify git version
	requiredGitVersion=1.7.12
	if ! versionOk $(git --version | tr -dc 0-9. ) "$requiredGitVersion"; then
		echo "$(git --version) must be at least $requiredGitVersion"
		exit 1
	fi
	echo "Build environment has been verified."

	echo "=================================================="
	echo "WORKSPACE: $WORKSPACE"
	echo "BUILD_NUMBER: $BUILD_NUMBER"
	echo "RHEL_VERSION: $RHEL_VERSION"
	echo "TC_VERSION: $TC_VERSION"
	echo "--------------------------------------------------"
}

# ---------------------------------------
function createSourceDir() {
	local target="$1-$TC_VERSION"
	local srcpath="$RPMBUILD/SOURCES/$target"
	mkdir -p "$srcpath" || { echo "Could not create $srcpath: $?"; exit 1; }
	echo "$srcpath"
}

# ---------------------------------------
function buildRpm () {
	for package in "$@"; do
		local pre="${package}-${TC_VERSION}-${BUILD_NUMBER}.${RHEL_VERSION}"
		local rpm="${pre}.$(uname -m).rpm"
		local srpm="${pre}.src.rpm"
		echo "Building the rpm."

		cd "$RPMBUILD" && \
			rpmbuild --define "_topdir $(pwd)" \
				 --define "traffic_control_version $TC_VERSION" \
				 --define "commit $(getCommit)" \
				 --define "build_number $BUILD_NUMBER.$RHEL_VERSION" \
				 -ba SPECS/$package.spec || \
				 { echo "RPM BUILD FAILED: $?"; exit 1; }

		echo
		echo "========================================================================================"
		echo "RPM BUILD FOR $package SUCCEEDED, See $DIST/$rpm for the newly built rpm."
		echo "========================================================================================"
		echo

		cp "$RPMBUILD/RPMS/$(uname -m)/$rpm" "$DIST/." || { echo "Could not copy $rpm to $DIST: $?"; exit 1; }
		cp "$RPMBUILD/SRPMS/$srpm" "$DIST/." || { echo "Could not copy $srpm to $DIST: $?"; exit 1; }
	done
}

# ---------------------------------------
function createTarball() {
	local projDir=$(cd "$1"; pwd)
	local projName=trafficcontrol
	local version=$(getVersion "$TC_DIR")
	local tarball="dist/apache-$projName-$version.tar.gz"
	local tardir=$(basename $tarball .tar.gz)

	# Create a BULDNUMBER file and add to tarball
	local bndir=$(mktemp -d)
        getBuildNumber >"$bndir/BUILD_NUMBER"

        # create the tarball only from files in repo and BUILD_NUMBER
        tar -czf "$tarball" -C "$bndir" BUILD_NUMBER -C "$projDir" --exclude-vcs --transform "s@^@$tardir/@S" $(git ls-files)
        rm -r "$bndir"
        echo "$tarball"
}

# ---------------------------------------
function createDocsTarball() {
	local projDir=$(cd "$1"; pwd)
	local projName=trafficcontrol
	local version=$(getVersion "$TC_DIR")
	local tarball="dist/apache-$projName-$version-docs.tar.gz"
	local tardir="${projDir}/docs/build/"

	# Create a BULDNUMBER file and add to tarball
	local bndir=$(mktemp -d)
        getBuildNumber >"$bndir/BUILD_NUMBER"

        # create the tarball only from files in repo and BUILD_NUMBER
        tar -czf "$tarball" -C "$bndir" BUILD_NUMBER -C "$tardir" . --exclude-vcs
        rm -r "$bndir"
        echo "$tarball"
}

# ----------------------------------------
# verify if the go compiler is version 1.11 or higher, returns 0 if if not. returns 1 if it is.
# 
function verify_and_set_go_version () {
  GO_VERSION="none"
  GO="none"
  go_in_path=`type -p go`
  for g in $go_in_path /usr/bin/go /usr/local/go/bin/go; do
    if [[ -z $g ]] || [[ ! -x $g ]]; then
      continue
    fi
    
    go_version=`$g version | awk '{print $3}'`

    if [[ $go_version =~ go([1-9])\.([1-9]+) ]] && [[ ${BASH_REMATCH[1]} -ge 1 ]] && [[ ${BASH_REMATCH[2]} -ge 11 ]]; then
      GO_VERSION="${BASH_REMATCH[1]}.${BASH_REMATCH[2]}"; export GO_VERSION
      GO=$g; export GO
      PATH=`dirname $g`:$PATH; export PATH
      echo "go version for $g is ${BASH_REMATCH[1]}.${BASH_REMATCH[2]}"
      echo "will use $g"
      return 1
    else
      if [[ $go_version =~ go([1-9])\.([1-9]+) ]]; then
        GO_VERSION="${BASH_REMATCH[1]}.${BASH_REMATCH[2]}"; export GO_VERSION
        echo "go version for $g is ${BASH_REMATCH[1]}.${BASH_REMATCH[2]}"
        continue
      fi
    fi
  done

  if [[ $GO == none ]]; then
    echo "ERROR: this build needs go 1.11 or greater and no usable go compiler was found, found GO_VERSION: $GO_VERSION"
    return 0
  fi
}