#!/bin/bash

function execute {
    cmd=("$@")
    echo
    echo "Executing ${cmd[*]} ..."
    echo
    # execute the command:
    "${cmd[@]}"
}

function confirm() {
    read -p "$1 ([y]es or [N]o): "
    case $(echo $REPLY | tr '[A-Z]' '[a-z]') in
        y|yes) echo "yes" ;;
        *)     echo "no" ;;
    esac
}

function getMessage() {
    if [[ -z "$@" ]]
    then
        echo false;
    fi

    echo $@
}

function showHelp() {
    echo
    echo "versiontag"
    echo "=========="
    echo
    echo "Automates version tag creation."
    echo 
    echo "Commands: patch|minor|major|current 'Tag message'"
    echo "          remove"
    echo "          current"
    echo
    echo "Examples:"
    echo "---------"
    echo 
    echo "Show current version: ./versiontag current"
    echo "Patch version:        ./versiontag patch 'Fix broken view'"
    echo "Minor version:        ./versiontag minor 'Add Customer filter by email'"
    echo "Major version:        ./versiontag major 'Blog module'"
    echo "Remove last version:  ./versiontag remove"
    echo
    exit 0
}

function showSuccess() {
    echo
    echo "Tag v$major.$minor.$patch was created in local repository."
    echo
    echo "Push it:"
    echo
    echo "    git push origin v$major.$minor.$patch"
    echo
    echo "Delete tag:"
    echo
    echo "    git tag -d v$major.$minor.$patch"
    echo
}


lasttag=`git describe --tags --long` || true

if [[ -z "$lasttag" ]]; then
    lasttag='v0.0.0'
fi

cleantag=${lasttag%%-*}

parts=(${cleantag//./ })

major=${parts[0]:1}
minor=${parts[1]}
patch=${parts[2]}

major=${major:0}
minor=${minor:0}
patch=${patch:0}

last="v$major.$minor.$patch"

mode=''
force=false

while [ -n "$1" ]
do
    case "$1" 
    in
        -f|--force)
            force=true;;
        -h|--help)
            showHelp
            exit 0;;
        patch) 
            patch=$((patch + 1)) 
            msg=$(getMessage "$2")
            shift 1
            mode='patch';;
        minor) 
            minor=$((minor + 1))
            patch=0 
            msg=$(getMessage "$2")
            shift 1
            mode='minor';;
        major) 
            major=$((major + 1)); minor=0
            patch=0 
            msg=$(getMessage "$2")
            shift 1
            mode='major';;
        current)
            echo "Current version: $last"
            exit 0;;
        remove)
            if [[ "yes" == $(confirm "Do you want to remove $last?") ]]; then
                execute git tag -d "$last"
                execute git push origin ":$last"
            fi
            exit 0;;
        help)
            showHelp;;
        *)
            echo "$1 option is not valid"
            exit 1;;
    esac

    shift 1;
done

if [[ false == "$msg" ]]; then
    echo
    echo "No message."
    exit 1;
fi

if [[ -z "$mode" ]]; then
    showHelp;
    exit 0;
fi   

echo "Current version : $last"
echo "New tag         : v$major.$minor.$patch"
echo
echo "Message         : $msg"

if [[ "$force" = true ]]; then
    execute git tag -a "v$major.$minor.$patch" -m "$msg ($mode version)"
    execute git push origin "v$major.$minor.$patch"
    echo 
    echo "Version tag created and pushed"
    exit 0;
fi

if [[ "no" == $(confirm "Do you agree?") ]]; then
    echo
    echo "No tag was created"
    exit 0;
fi

execute git tag -a "v$major.$minor.$patch" -m "$msg ($mode version)"

showSuccess;

if [[ "yes" == $(confirm "Do you want to push this tag right now?") ]]; then
    execute git push origin "v$major.$minor.$patch"
fi

exit 0