#!/bin/bash

readonly THISSCRIPT=$0
readonly BRANCH_NIGHTLY="unstable"
readonly DISTRIBS="stretch buster"
readonly TIMETAG="$(date +%Y%m%d%H%M)"
readonly PACKAGES="moulinette SSOwat yunohost yunohost-admin"
readonly FORCE="false"
readonly LAST_BUILDS_CACHE="/var/cache/vinaigrette/last_builds/"

source /home/vinaigrette/config/config


function main()
{

    mkdir -p $LAST_BUILDS_CACHE

    #if [[ "$(tty)" == "not a tty" ]]
    #then
    #    echo "You aint in a tty (are you in a 'lxc exec' ?)"
    #    echo "The script can't run because pbuilder won't be happy :|"
    #    exit
    #fi

    for PACKAGE in $PACKAGES;
    do
	for DISTRIB in $DISTRIBS;
	do
		echo "-------------------------------------"
		echo "Looking for update in ${PACKAGE} for ${DISTRIB}... "

		build_if_needed $PACKAGE $DISTRIB
	done

    done
    echo "-------------------------------------"
}


function build_if_needed()
{
    local PACKAGE=$1
    local DISTRIB=$2
    local LAST_BUILD_FOR_THIS_PACKAGE=$LAST_BUILDS_CACHE/${DISTRIB}_${BRANCH_NIGHTLY}_${PACKAGE}

    cd $GIT_REPOS/$PACKAGE

    git fetch origin >/dev/null 2>/dev/null

    # Check if there's a branch named distrib-branch (e.g. stretch-unstable)
    # By default, keep just 'branch'
    BRANCH_NIGHTLY_GIT="$BRANCH_NIGHTLY"
    if git branch -ar | grep -q origin/$DISTRIB-$BRANCH_NIGHTLY
    then
	    BRANCH_NIGHTLY_GIT="$DISTRIB-$BRANCH_NIGHTLY"
    fi

    # If the branch name is an alias to another branch, "resolve" the alias
    if grep -q "ref: " .git/refs/heads/$BRANCH_NIGHTLY_GIT 2>/dev/null
    then
	    BRANCH_NIGHTLY_GIT=$(cat .git/refs/heads/$BRANCH_NIGHTLY_GIT | tr '/' ' ' | awk '{print $4}')
    fi

    git checkout $BRANCH_NIGHTLY_GIT >/dev/null 2>/dev/null
    git pull origin $BRANCH_NIGHTLY_GIT >/dev/null 2>/dev/null
    git reset --hard origin/$BRANCH_NIGHTLY_GIT

    # Check if build is needed

    if [ -e $LAST_BUILD_FOR_THIS_PACKAGE ] 
    then
	    TIMESTAMP_LASTBUILD=$(stat -c %Y $LAST_BUILD_FOR_THIS_PACKAGE)
    else
	    TIMESTAMP_LASTBUILD=0
    fi
    TIMESTAMP_HEAD=$(git show -s --format=%ct HEAD)

    if [ $TIMESTAMP_HEAD -lt $TIMESTAMP_LASTBUILD ]
    then
	if ! "$FORCE";
	then
		echo "Sources up-to-date, nothing to build."
		return
	else
		echo "Sources up-to-date but forcing build anyway."
	fi
    fi

    VERSION=$(dpkg-parsechangelog -S Version 2>/dev/null)
    VERSION_NIGHTLY="${VERSION}+${TIMETAG}"

    # Tweak the changelog temporarily
    echo "> Setting version in changelog to ${VERSION_NIGHTLY}"
    rm -f debian/changelog.dch
    cp debian/changelog debian/changelog.old
    dch --package "${PACKAGE}" \
        --force-bad-version \
	-v "${VERSION_NIGHTLY}" \
	-D "${BRANCH_NIGHTLY}" \
	--force-distribution \
	"Daily build." \
        > /dev/null 2>&1

    head -n 5 debian/changelog

    # Launch the build using build_deb script
    build

    touch $LAST_BUILD_FOR_THIS_PACKAGE

    # Restore changelog
    echo "> Restoring previous changelog"
    cd $GIT_REPOS/$PACKAGE
    cp debian/changelog.old debian/changelog
    rm debian/changelog.old

}

function build()
{
   # Create temporary folder
   TMP_FOLDER=$(mktemp -d)

   # Move files to a tmp folder
   echo "> Exporting in $TMP_FOLDER ...  "
   git ls-files | xargs tar -czf archive.tar.gz
   cat archive.tar.gz | tar -xz -C $TMP_FOLDER
   rm archive.tar.gz

   # Build Debian package
   echo "> Starting build ..."
   cd $TMP_FOLDER
   $BUILD_DEB $DISTRIB $BRANCH_NIGHTLY .
}

main