#!/bin/sh
export LC_ALL=C

do_clone()
{
    set -ex
    if ! test -e "$1" ; then
        git clone "$2" "$1"
    fi
    (
        cd "$1"
        git remote set-url origin "$2"
        git fetch
        git submodule update --init
    )
}

do_clone_all()
{
    do_clone "ffmpeg"     "https://github.com/FFmpeg/FFmpeg.git"
    #do_clone "fribidi"    "http://anongit.freedesktop.org/git/fribidi/fribidi.git"
    do_clone "libass"     "https://github.com/libass/libass.git"
    do_clone "libplacebo" "https://github.com/haasn/libplacebo.git"
    do_clone "mpv"        "https://github.com/mpv-player/mpv.git"
}

do_gitmaster()
{
    set -ex
    (
        cd "$1"
        git checkout origin/master
        git remote prune origin
    )
}

versort_with_prefix()
{
	# Emulate sort -V using a known prefix. Filter out anything else.
	sed -n -e "s/^$1\([0-9]\)/\\1/p" |\
		sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 |\
		sed -e "s/^/$1/"
	# GNU version of the same:
	# grep "^$2[0-9]" | sort -V
}

do_releasetag()
{
    local prefix=  # by default, don't use a prefix
    case "$1" in
        ffmpeg) prefix=n;;  # e.g. n3.3.1
        mpv|libplacebo)    prefix=v;;  # e.g. v0.26.0
    esac

    (
        cd "$1"
        version=`git tag | grep -v rc | grep -v dev | versort_with_prefix "$prefix" | tail -n 1`
        git checkout refs/tags/"$version"
    )
}

do_fixedref()
{
    (
        cd "$1"
        git checkout "$2"
    )
}

# args: $1: project name, $2: release/master/@foo [,$3: non-empty to ignore the config file]
checkout()
{
    local branch="$2"
    if [ -z "$3" ] && [ -d config/ ] && [ -f config/branch-$1 ]; then
        branch="$(cat config/branch-$1)"
    fi

    case "$branch" in
        master)  do_gitmaster $1;;
        release) do_releasetag $1;;
        @*)      do_fixedref $1 "${branch#@}";;  # everything after the '@' prefix
        *)       >&2 printf "%s\n" "Error: Don't know how to checkout '$branch'"
                 return 1
    esac
}

# fallback targets: release/master/@foo if no config file
checkout_ffmpeg=master
#checkout_fribidi=release
checkout_libass=master
checkout_libplacebo=master
checkout_mpv=master


checkout_all()
{
    set -ex
    do_clone_all
    checkout ffmpeg $checkout_ffmpeg
    #$checkout fribidi $checkout_fribidi
    checkout libass $checkout_libass
    checkout libplacebo $checkout_libplacebo
    checkout mpv $checkout_mpv
}

do_update_debian_versions()
{
  scripts/debian-update-versions $1
}

if [ x"$1" != x"--skip-selfupdate" ]; then
    (
        set -ex
        git pull --rebase
    )
    exec "$0" --skip-selfupdate "$@"
fi
shift

# allow checkout master/release without checking the config files
case "$1" in
    --master)
        checkout_ffmpeg="master -"
        #checkout_fribidi="master -"
        checkout_libass="master -"
        checkout_libplacebo="master -"
        checkout_mpv="master -"
        ;;
    --release)
        checkout_ffmpeg="release -"
        checkout_mpv="release -"
        ;;
    '')
        ;;
    *)
        echo >&2 "$0 --master"
        echo >&2 "$0 --release"
        exit 0
        ;;
esac

checkout_all

do_update_debian_versions