#!/bin/bash

__make_ver() {
    local level=$1
    local old=$2
    local oldx=${old%.*.*}
    local oldz=${old#*.*.}
    local tmpy=${old%.*}
    local oldy=${tmpy#*.}
    case $level in
        x) new="$((oldx+1)).0.0"            ;;
        y) new="$oldx.$((oldy+1)).0"        ;;
        z) new="$oldx.$oldy.$((oldz+1))"    ;;
        *) die "invalid release level: $1"  ;;
    esac
    echo "$new"
}

__release() {
    #
    # Prepare release
    #
    # Span release routines: make a signed tag, check branch
    # and update release branch
    #
    # FIXME: Using PRERELEASE as build.sh:get_version() does may not be
    #        compatible with this release strategy
    #
    local level=$1
    git rev-parse HEAD >&/dev/null || die "cannot release outside git repo"
    local lastfile=$(git diff-tree --no-commit-id --name-only -r HEAD)
    local lasttag=$(git tag | grep ^v | sort -V | tail -n1)
    local changelog="$(git log --oneline "$lasttag..HEAD")"
    local curbranch=$(git rev-parse --abbrev-ref HEAD)
    local dirt="$(git diff --shortstat 2>/dev/null)"

    local newver=$(__make_ver "$level" "${lasttag#v}")
    local newtag=v$newver
    local higher=$(echo -e "$oldtag\n$newtag" | sort -V | tail -n1)

    test "$lastfile" = config.mk \
     || die "last change must be version bump in config.mk"

    test -n "$lasttag" \
     || die "cannot find last tag"

    test "$newtag" = "$higher" \
     || die "generated tag looks older: $oldtag<$newtag"

    grep -qw "$newver" config.mk \
     || die "new version not in config.mk: $newver"

    grep '^....... WIP ' <<<"$changelog" \
     && die "WIP commit since $lasttag"

    grep -qw "$curbranch" <<<"$RELSRC" \
     || die "you are not on RELSRC branch: $RELSRC"

    test -z "$dirt" \
     || die "tree is dirty: $dirt"

    # FIXME: Have user prepare proper message with changelog

    set -e
    git tag -m "$MKIT_PROJNAME $newtag - $CODENAME" "$newtag"
    git branch -f "$RELDST" "$newtag"
}

release_x() {
    __release x
}

release_y() {
    __release y
}

release_z() {
    __release z
}