#!/usr/bin/env bash

print_usage()
{
    echo "USAGE: $0 <slim|full|zig> [rust version] [cross version] [zig version]"
    echo
    echo "Arguments:"
    echo -e "\t<slim|full>\tSlim build (without targets) or Full build (with targets)"
    echo
    echo -e "\t[rust version]\tVersion of rust (https://github.com/rust-lang/rust)"
    echo -e "\t[cross version]\tVersion of cross (https://github.com/cross-rs/cross)"
    echo -e "\t[zig version]\tVersion of zig (https://ziglang.org/download)"
    echo -e "\t\t\tUse 'master' for master version of zig"
    echo
    echo "All versions default to the latest release."
}

get_latest_release() {
  curl --silent "https://api.github.com/repos/$1/releases/latest" | # Get latest release from GitHub api
    grep '"tag_name":' |                                            # Get tag line
    sed -E 's/.*"v?([^"]+)".*/\1/'                                  # Pluck JSON value
}

get_version() {
    case $2 in
        latest | "")
            echo $(get_latest_release $1)
            ;;
        *)
            echo $2
            ;;

    esac
}


if command -v podman &> /dev/null
then
    BUILDER=podman
elif command -v docker &> /dev/null
then
    BUILDER=docker
else
    echo "Prerequisite failed: either podman or docker must be installed"
    exit 1
fi

if ! command -v envsubst &> /dev/null
then
    echo "Prerequisite failed: envsubst must be installed"
    exit 1
fi

if [ $# -lt 1 ]; then
    print_usage
    exit 1
fi

case ${1} in
    full | slim | zig)
        ;;

    *)
        echo "ERROR: The first argument mus either be 'full' or 'slim'."
        echo
        print_usage
        exit 1
        ;;
esac

set -e -o pipefail

if [ -z "$2" ]; then
    RUST_VERSION=$(get_version 'rust-lang/rust' $2)
else
    RUST_VERSION=$2
fi

if [ -z "$3" ]; then
    CROSS_VERSION=$(get_latest_release 'cross-rs/cross')
else
    CROSS_VERSION=$3
fi

ZIG_VERSION=$(get_latest_release 'ziglang/zig')

export RUST_VERSION
export CROSS_VERSION
export ZIG_VERSION

echo "Creating a ${1} build with the following versions:"
echo -e "\tRust:\t${RUST_VERSION}"
echo -e "\tcross:\t${CROSS_VERSION}"
echo -e "\tzig:\t${ZIG_VERSION}"

case $1 in
    full | slim)
        IMAGE="img.kie.rs/jjkiers/rust-crossbuild:rust${RUST_VERSION}-cross${CROSS_VERSION}-${1}"
    ;;
    zig)
        IMAGE="img.kie.rs/jjkiers/rust-crossbuild:rust${RUST_VERSION}-zig${ZIG_VERSION}-${1}"
    ;;
esac

envsubst < Dockerfile-${1} | ${BUILDER} build -f - \
    -t ${IMAGE} \
    .

echo "Built image ${IMAGE}"

exit 0

${BUILDER} push ${IMAGE}

if [ $? -ne 0 ]; then
    echo "Pushing failed: ${BUILDER} push ${IMAGE}"
else
    echo "Pushed image ${IMAGE}"
fi