#!/usr/bin/env bash

ENGINE_DIR="$1"
VERSION="$2"

[[ $# < 2 ]] && echo 'not enough args' && exit 1

DATE_COMMAND="date"
if [[ $(uname) -eq "Darwin" ]]; then
    DATE_COMMAND="docker run --rm alpine date"
fi

TZ=UTC

tilde='~' # ouch Bash 4.2 vs 4.3, you keel me
# git running in different directories, backwards compatible too
GIT_COMMAND="git -C $ENGINE_DIR"
debVersion="${VERSION//-/$tilde}" # using \~ or '~' here works in 4.3, but not 4.2; just ~ causes $HOME to be inserted, hence the $tilde
# if we have a "-dev" suffix or have change in Git, let's make this package version more complex so it works better
if [[ "$VERSION" == *-dev ]]; then
    gitUnix="$($GIT_COMMAND log -1 --pretty='%at')"
    gitDate="$($DATE_COMMAND --date "@$gitUnix" +'%Y%m%d.%H%M%S')"
    gitCommit="$($GIT_COMMAND log -1 --pretty='%h')"
    gitVersion="git${gitDate}.0.${gitCommit}"
    debVersion="$debVersion~$gitVersion"

    # $ dpkg --compare-versions 1.5.0 gt 1.5.0~rc1 && echo true || echo false
    # true
    # $ dpkg --compare-versions 1.5.0~rc1 gt 1.5.0~git20150128.112847.17e840a && echo true || echo false
    # true
    # $ dpkg --compare-versions 1.5.0~git20150128.112847.17e840a gt 1.5.0~dev~git20150128.112847.17e840a && echo true || echo false
    # true

    # ie, 1.5.0 > 1.5.0~rc1 > 1.5.0~git20150128.112847.17e840a > 1.5.0~dev~git20150128.112847.17e840a
fi

echo "$debVersion"