#!/bin/bash

# use this as: PUSH=0 ./build ... in order to set the variable. default is PUSH=1
PUSH=${PUSH:-1}
# use this as: FORCE=1 ./build ... in order to set the variable. default is FORCE=0
FORCE=${FORCE:-0}
# use this as: USE_LOCAL=1 ./build ... in order to set the variable. default is USE_LOCAL=0
USE_LOCAL=${USE_LOCAL:-0}

if [ ! "$1" == "" ]; then 
    IMAGE_VERSION=$1
else
    echo "No Nextcloud version specified. Exiting (1)."
    exit 1
fi

if [ ! "$2" == "" ]; then 
    VARIANTS=$2
else
    VARIANTS=("fpm" "fpm-alpine")
fi

# set username and password
# requires vars DOCKER_USER and DOCKER_PASS to be defined before calling.
# useful functions.
function docker_tag_exists() {
    TOKEN=$(curl -s -H "Content-Type: application/json" -X POST -d '{"username": "'${DOCKER_USER}'", "password": "'${DOCKER_PASS}'"}' https://hub.docker.com/v2/users/login/ | jq -r .token)
    curl --silent -f --head -lL https://hub.docker.com/v2/repositories/$1/tags/$2/ > /dev/null
}

for item in "${!VARIANTS[@]}"
do
    IMAGE_VARIANT=${VARIANTS[$item]}
    UPSTREAM_IMAGE=nextcloud
    UPSTREAM_IMAGE_TAG=${IMAGE_VERSION}-${IMAGE_VARIANT}
    IMAGE=bkraul/nextcloud

    echo "Building Nextcloud ${IMAGE_VERSION}, variant: ${IMAGE_VARIANT}..."

    # pull the parent image from docker hub, if it doesn't already exist locally.
    LOCAL_EXISTS=$(docker images --format "{{.Repository}}:{{.Tag}}" | grep -x ${UPSTREAM_IMAGE}:${UPSTREAM_IMAGE_TAG})
    echo "LOCAL_EXISTS: $LOCAL_EXISTS"
    echo "USE_LOCAL: $USE_LOCAL"
    if [[ $USE_LOCAL == 1 && $LOCAL_EXISTS != "" ]]; then
        echo "Using local image ${UPSTREAM_IMAGE}:${UPSTREAM_IMAGE_TAG}..."
    else
        echo "Pulling upstream image ${UPSTREAM_IMAGE}:${UPSTREAM_IMAGE_TAG}..."
        docker pull ${UPSTREAM_IMAGE}:${UPSTREAM_IMAGE_TAG} > /dev/null    
    fi

    UPSTREAM_ID=$(docker image inspect --format='{{index .Id}}' ${UPSTREAM_IMAGE}:${UPSTREAM_IMAGE_TAG})
    UPSTREAM_ID=${UPSTREAM_ID:7}

    # get the version number.
    NEXTCLOUD_VERSION=$(docker inspect ${UPSTREAM_IMAGE}:${UPSTREAM_IMAGE_TAG} | jq -r '.[].Config.Env[] | select(match("^NEXTCLOUD_VERSION"))')
    NEXTCLOUD_VERSION=${NEXTCLOUD_VERSION:18}
    IMAGE_TAG=${NEXTCLOUD_VERSION}-${IMAGE_VARIANT}

    if docker_tag_exists ${IMAGE} ${IMAGE_TAG}; then
        # nothing to do, the image already exists.
        echo Image ${IMAGE}:${IMAGE_TAG} already exists.
        echo "----------------------------"
        if [ $FORCE == 0 ]; then continue; fi
    fi

    # determine the common files to use.
    # Dockerfile
    DOCKERFILE_DIR="./build-common/dockerfile"
    DOCKERFILE=""
    if [ -f "${DOCKERFILE_DIR}/Dockerfile" ]; then DOCKERFILE="${DOCKERFILE_DIR}/Dockerfile"; fi
    if [ -f "${DOCKERFILE_DIR}/Dockerfile-${IMAGE_VERSION}" ]; then DOCKERFILE="${DOCKERFILE_DIR}/Dockerfile-${IMAGE_VERSION}"; fi
    if [ -f "${DOCKERFILE_DIR}/Dockerfile-${IMAGE_VARIANT}" ]; then echo "Image variant"; DOCKERFILE="${DOCKERFILE_DIR}/Dockerfile-${IMAGE_VARIANT}"; fi
    if [ -f "${DOCKERFILE_DIR}/Dockerfile-${IMAGE_VARIANT}-${IMAGE_VERSION}" ]; then DOCKERFILE="${DOCKERFILE_DIR}/Dockerfile-${IMAGE_VARIANT}-${IMAGE_VERSION}"; fi

    # if no valid Dockerfile is found, we abort current build and go to next variant if available.
    if [ "${DOCKERFILE}" = "" ]; then echo "No valid Dockerfile found."; continue; fi

    # image doesn't exist we need build and push
    echo Image ${IMAGE}:${IMAGE_TAG} does not exist.
    echo "Building image(s)..."

    docker build \
        --file ${DOCKERFILE} \
        --no-cache \
        -t ${IMAGE}:${UPSTREAM_IMAGE_TAG} \
        -t ${IMAGE}:${IMAGE_TAG} \
        --build-arg BASE_IMAGE="${UPSTREAM_IMAGE}:${UPSTREAM_IMAGE_TAG}" \
        --progress plain \
        ./build-common

    if [ $? == 0 ]; then
        # don't push if specified so (continue the variant loop).
        if [ ${PUSH} == 0 ]; then
            echo "----------------------------"
            continue;
        fi

        echo "Pushing image(s)..."
        docker push ${IMAGE}:${IMAGE_TAG}
        docker push ${IMAGE}:${UPSTREAM_IMAGE_TAG}
    else
        echo "The build operation failed."
        echo "Please debug and try again."
    fi
    echo "----------------------------"
done