#!/bin/bash

USER_CONTAINER_CONFIG="$HOME/.local/docker/.bwlp-user-conf"

echo "+ source user_config $USER_CONTAINER_CONFIG"
source $USER_CONTAINER_CONFIG

load_image () {

	IMAGE_SIZE=$(stat --printf="%s" $VM_DISKFILE_RO)
	# check file size of VM_DISKFILE_RO is equals to 4096 = 4kB (because of padding)

	if [[ $CONTAINER_IMAGE_CONTEXT == "DOCKER_ARCHIVE" ]]; then
		# In this case a pre build container image (tar archive from "docker save ...") 
		# will be loaded into the local docker daemon. 
		echo "+ load container image... (please be patient)"
		# create TMP_FILE for docker load output
		local TMP_FILE=$(mktemp)

		# TODO no progress output for docker load
		# load image from tar file
		pv -cN "Image Transfer" < $VM_DISKFILE_RO | docker load -q > $TMP_FILE
		echo "+ $(cat $TMP_FILE)"

		# repotags in docker-archive optional, so the load output can be
		# "Loaded image ID: sha256:<DIGES>" OR "Loaded image: <RepoTag>"
		local repotag=$(head -n 1 $TMP_FILE | awk -F ': ' '{print $2}')
		# rename image and remove old tag
		writelog "docker tag $repotag $CONTAINER_IMAGE_NAME"
		docker tag "$repotag" "$CONTAINER_IMAGE_NAME"
		rm -f -- "$TMP_FILE"
	
	elif [[ "$CONTAINER_IMAGE_CONTEXT" == "DOCKERFILE" || "$CONTAINER_IMAGE_CONTEXT" == "GIT_REPO" ]]; then
		echo "+ build container image with build_context"
		echo "+ docker build --tag $CONTAINER_IMAGE_NAME $CONTAINER_BUILD_CONTEXT"
		docker build --tag $CONTAINER_IMAGE_NAME $CONTAINER_BUILD_CONTEXT
	fi
	retval=$?
	return $retval
}

function build_container_image() 
{
	echo "+ build container image with build_context"
	echo "+ docker build --tag $CONTAINER_IMAGE_TAG $CONTAINER_IMAGE_BUILD_CONTEXT"
	docker build --tag $CONTAINER_IMAGE_TAG $CONTAINER_IMAGE_BUILD_CONTEXT
}

function load_container_image()
{
	# load a pre build container image (tar archive from "docker save ...") 
	# into the local docker daemon. 
	echo "+ load container image... (please be patient)"
	# create TMP_FILE for docker load output
	local TMP_FILE=$(mktemp)

	# TODO no progress output for docker load
	# load image from tar file
	pv -cN "Image Transfer" < $DATA_CONTAINER_DNBD3_IMAGE | docker load -q > $TMP_FILE
	retval=$?
	echo "+ $(cat $TMP_FILE)"

	# repotags in docker-archive optional, so the load output can be
	# "Loaded image ID: sha256:<DIGES>" OR "Loaded image: <RepoTag>"
	local repotag=$(head -n 1 $TMP_FILE | awk -F ': ' '{print $2}')
	# rename image and remove old tag
	writelog "docker tag $repotag $CONTAINER_IMAGE_TAG"
	docker tag "$repotag" "$CONTAINER_IMAGE_TAG"
	rm -f -- "$TMP_FILE"
	return $retval
}

function prepare_dnbd3_mount()
{
	# prepare dnbd3 mount
	DATA_CONTAINER_DNBD3_MOUNT="${DATA_CONTAINER_DIR}/dnbd3.fuse"
	DATA_CONTAINER_DNBD3_LOG="${DATA_CONTAINER_DIR}/dnbd3.log"
	DATA_CONTAINER_DNBD3_IMAGE="${DATA_CONTAINER_DNBD3_MOUNT}/img"

	mkdir -p $DATA_CONTAINER_DNBD3_MOUNT
	# check DNBD3_MOUNT dir exists and is not used

	if [[ -d $DATA_CONTAINER_DNBD3_MOUNT ]]; then
		if [[ -n "$(ls -A $DATA_CONTAINER_DNBD3_MOUNT)" ]]; then
			writelog "+ mount directory not empty"
			umount "$DATA_CONTAINER_DNBD3_MOUNT"
			find "$DATA_CONTAINER_DNBD3_MOUNT" -mindepth 1 -delete
		fi
	fi

	source /opt/openslx/config
	writelog "dnbd3-fuse --host $SLX_DNBD3_SERVERS --image $BWLP_IMAGE_PATH $DATA_CONTAINER_DNBD3_MOUNT"
	dnbd3-fuse --log $DATA_CONTAINER_DNBD3_LOG  --host "${SLX_DNBD3_SERVERS}" --image $BWLP_IMAGE_PATH $DATA_CONTAINER_DNBD3_MOUNT > /dev/null 2>&1
	echo "RETVAL $?"
	if [[ ! -f $DATA_CONTAINER_DNBD3_IMAGE ]]; then
		writelog "+ -FAIL- dnbd3-fuse failed to mount image"
		return 1
	fi

	return 0
}


function prepare_data_volume() 
{
	local display_name=$( jq -r '.displayname' ${DATA_CONTAINER_METADATA} )

	echo "+ prepare data container $display_name"
	local build_context_method=$( jq -r '.build_context_method' ${DATA_CONTAINER_METADATA} )
	local image_file_size=$( jq -r '.filesize' ${DATA_CONTAINER_METADATA} )
	if [[ "$build_context_method" == "0" ]]; then
		writelog "+ container_build_context: dockerfile"
		CONTAINER_IMAGE_BUILD_CONTEXT="$DATA_CONTAINER_DIR"
		CONTAINER_IMAGE_TAG="$(echo ${display_name} | tr -dc '[:alnum:]' | tr '[:upper:]' '[:lower:]')"
		DATA_CONTAINER_IMAGE_NAME=$CONTAINER_IMAGE_TAG
		build_container_image
		retval=$?
	elif [[ "$build_context_method" == "1" ]]; then
		writelog "+ container_build_context: git url"
		CONTAINER_IMAGE_BUILD_CONTEXT=$( jq -r '.build_context_url' ${DATA_CONTAINER_METADATA} )
		CONTAINER_IMAGE_TAG="$(echo ${display_name} | tr -dc '[:alnum:]' | tr '[:upper:]' '[:lower:]')"
		DATA_CONTAINER_IMAGE_NAME=$CONTAINER_IMAGE_TAG
		build_container_image
		retval=$?	
	elif [[ "$build_context_method" == "2" ]]; then
		writelog "+ pull data container"
		DATA_CONTAINER_REPO=$( jq -r '.image_repo' ${DATA_CONTAINER_METADATA} )
		DATA_CONTAINER_IMAGE_NAME="$DATA_CONTAINER_REPO"
		docker pull "$DATA_CONTAINER_REPO"
		retval=$?
	elif  [[ "$build_context_method" == "3" ]]; then
		CONTAINER_IMAGE_TAG="$(echo ${display_name} | tr -dc '[:alnum:]' | tr '[:upper:]' '[:lower:]')"
		DATA_CONTAINER_IMAGE_NAME=$CONTAINER_IMAGE_TAG
		BWLP_IMAGE_PATH=$( jq -r '.imagepath' ${DATA_CONTAINER_METADATA})
		prepare_dnbd3_mount && load_container_image
		retval=$?
	else
		writelog "+ no proper build_context_method (=$build_context_method)"
		return 1
	fi

	## create the volume
	if [[ $retval == 0 ]]; then
		VOLUME_NAME="volume_$(echo ${display_name} | tr -dc '[:alnum:]' | tr '[:upper:]' '[:lower:]')"
		echo "+ create volume VOLUME_NAME=$VOLUME_NAME"
		docker volume create $VOLUME_NAME
		
		# TODO assumption: every data container stores data at /data/
		writelog "+ populate volume with container data"
		writelog "+ docker run -it --rm -v $VOLUME_NAME:/data/ $DATA_CONTAINER_IMAGE_NAME"
		docker run -itd --rm -v $VOLUME_NAME:/data/ $DATA_CONTAINER_IMAGE_NAME
		
		source $DATA_CONTAINER_MOUNT_INFO
		CONTAINER_BIND_MOUNT_STRING+=" --mount type=volume,source=${VOLUME_NAME},target=$MOUNT_TARGET"
	fi
}

function process_volume_mount_info()
{
	for DATA_CONTAINER_DIR in $VOLUME_MOUNT_INFO; do
		echo $DATA_CONTAINER_DIR
		DATA_CONTAINER_METADATA="${DATA_CONTAINER_DIR}/metadata"
		DATA_CONTAINER_MOUNT_INFO="${DATA_CONTAINER_DIR}/mount_info"

		prepare_data_volume
	done
}


main () 
{

	if [[ -n "$VOLUME_MOUNT_INFO" ]]; then
		echo "+ prepare volumes from data container"
		process_volume_mount_info
	fi

	if [[ "$CONTAINER_IMAGE_CONTEXT" == "CONTAINER_REPO" ]]; then
		echo "pull container $CONTAINER_REPO_NAME"
		docker pull $CONTAINER_REPO_NAME

		[ "$?" != 0 ] && echo ".. docker pull not successful ...giving up..." && exit -1

		CONTAINER_IMAGE_NAME="$CONTAINER_REPO_NAME"
	fi

	# TODO only check by image name could be bad, images whith a same name could exist
	
	# check if the container_image_name already loaded in docker daemon
	if [[ -z $(docker images $CONTAINER_IMAGE_NAME -q) ]]; then
		echo "+ Image unknown by docker daemon ..."
		load_image

		if [[ "$retval" != "0" ]]; then
			echo "...could not build/load container image!...giving up..."
			return -1
		fi
	fi

	if [[ -n "$(docker ps -aq)" ]]; then
		echo "+ cleanup running container"
		docker rm --force $(docker ps -aq) > /dev/null
	fi

	echo "+ start container..."
	echo "+ docker run $CONTAINER_RUN_OPTIONS $CONTAINER_BIND_MOUNT_STRING $CONTAINER_IMAGE_NAME $CONTAINER_RUN_COMMAND"
	docker run $CONTAINER_RUN_OPTIONS $CONTAINER_BIND_MOUNT_STRING $CONTAINER_IMAGE_NAME $CONTAINER_RUN_COMMAND

	if [[ "$?" != "0" ]]; then
		echo "...container start failed!...giving up..."
		return -1
	fi
	
	if [[ -n $RUNSCRIPT ]]; then
		echo "+ execute user runscript"
		NOHUP_TMP=$(mktemp)
		nohup /bin/bash $RUNSCRIPT > "$NOHUP_TMP" & tail -f "$NOHUP_TMP"
	fi 
}

main 

# keeping terminal open
bash