#!/bin/bash

# build.sh checks if docker image with same sha256 exists remotely.
# if exists, do nothing, if not, build the image

commit_sha="${DRONE_COMMIT_SHA}"
image_path="${REGISTRY}${REGISTRY_PROJECT}"

if [ "${DRONE_TAG}" != "" ]; then
    tag="${DRONE_TAG}"
else
    tag="${DRONE_COMMIT_SHA}"
fi

# Starting Docker daemon.
/usr/local/bin/dockerd --data-root=/var/lib/docker --max-concurrent-uploads 1 &

# Wait for it.
echo "* Waiting for Docker daemon to start..."
while true; do
    if docker ps &>/dev/null; then
        break
    fi
done

echo "* Logging in to registry..."
docker login -u "${REGISTRY_USERNAME}" -p "${REGISTRY_PASSWORD}" "${REGISTRY}"

echo "* Building docker image ${image_path}:${tag}..."

if docker manifest inspect "${image_path}:${tag}" >/dev/null; then
    echo "* Docker image ${image_path}:${tag} is already exists on remote, no rebuilt necessary."
    exit 0
fi

docker build --pull --build-arg VCS_REF="${commit_sha}" --build-arg VCS_URL="${image_path}" --tag "${image_path}:${tag}" .
docker push "${image_path}:${tag}"