#!/bin/bash -e

# shellcheck disable=SC2119
run_sub_stage()
{
	log "Begin ${SUB_STAGE_DIR}"
	pushd "${SUB_STAGE_DIR}" > /dev/null
	for i in {00..99}; do
		if [ -f "${i}-debconf" ]; then
			log "Begin ${SUB_STAGE_DIR}/${i}-debconf"
			on_chroot << EOF
debconf-set-selections <<SELEOF
$(cat "${i}-debconf")
SELEOF
EOF

		log "End ${SUB_STAGE_DIR}/${i}-debconf"
		fi
		if [ -f "${i}-packages-nr" ]; then
			log "Begin ${SUB_STAGE_DIR}/${i}-packages-nr"
			PACKAGES="$(sed -f "${SCRIPT_DIR}/remove-comments.sed" < "${i}-packages-nr")"
			if [ -n "$PACKAGES" ]; then
				on_chroot << EOF
apt-get install --no-install-recommends -y $PACKAGES
EOF
			    if [ "${USE_QCOW2}" = "1" ]; then
				on_chroot << EOF
apt-get clean
EOF
			    fi
			fi
			log "End ${SUB_STAGE_DIR}/${i}-packages-nr"
		fi
		if [ -f "${i}-packages" ]; then
			log "Begin ${SUB_STAGE_DIR}/${i}-packages"
			PACKAGES="$(sed -f "${SCRIPT_DIR}/remove-comments.sed" < "${i}-packages")"
			if [ -n "$PACKAGES" ]; then
				on_chroot << EOF
apt-get install -y $PACKAGES
EOF
			    if [ "${USE_QCOW2}" = "1" ]; then
				on_chroot << EOF
apt-get clean
EOF
			    fi
			fi
			log "End ${SUB_STAGE_DIR}/${i}-packages"
		fi
		if [ -d "${i}-patches" ]; then
			log "Begin ${SUB_STAGE_DIR}/${i}-patches"
			pushd "${STAGE_WORK_DIR}" > /dev/null
			if [ "${CLEAN}" = "1" ]; then
				rm -rf .pc
				rm -rf ./*-pc
			fi
			QUILT_PATCHES="${SUB_STAGE_DIR}/${i}-patches"
			SUB_STAGE_QUILT_PATCH_DIR="$(basename "$SUB_STAGE_DIR")-pc"
			mkdir -p "$SUB_STAGE_QUILT_PATCH_DIR"
			ln -snf "$SUB_STAGE_QUILT_PATCH_DIR" .pc
			quilt upgrade
			if [ -e "${SUB_STAGE_DIR}/${i}-patches/EDIT" ]; then
				echo "Dropping into bash to edit patches..."
				bash
			fi
			RC=0
			quilt push -a || RC=$?
			case "$RC" in
				0|2)
					;;
				*)
					false
					;;
			esac
			popd > /dev/null
			log "End ${SUB_STAGE_DIR}/${i}-patches"
		fi
		if [ -x ${i}-run.sh ]; then
			log "Begin ${SUB_STAGE_DIR}/${i}-run.sh"
			./${i}-run.sh
			log "End ${SUB_STAGE_DIR}/${i}-run.sh"
		fi
		if [ -f ${i}-run-chroot.sh ]; then
			log "Begin ${SUB_STAGE_DIR}/${i}-run-chroot.sh"
			on_chroot < ${i}-run-chroot.sh
			log "End ${SUB_STAGE_DIR}/${i}-run-chroot.sh"
		fi
	done
	popd > /dev/null
	log "End ${SUB_STAGE_DIR}"
}


run_stage(){
	log "Begin ${STAGE_DIR}"
	STAGE="$(basename "${STAGE_DIR}")"

	pushd "${STAGE_DIR}" > /dev/null

	STAGE_WORK_DIR="${WORK_DIR}/${STAGE}"
	ROOTFS_DIR="${STAGE_WORK_DIR}"/rootfs

	if [ "${USE_QCOW2}" = "1" ]; then 
	    if [ ! -f SKIP ]; then
		load_qimage
	    fi
	else
	    # make sure we are not umounting during export-image stage
	    if [ "${USE_QCOW2}" = "0" ] && [ "${NO_PRERUN_QCOW2}" = "0" ]; then
    		unmount "${WORK_DIR}/${STAGE}"
	    fi
	fi
	
	if [ ! -f SKIP_IMAGES ]; then
		if [ -f "${STAGE_DIR}/EXPORT_IMAGE" ]; then
			EXPORT_DIRS="${EXPORT_DIRS} ${STAGE_DIR}"
		fi
	fi
	if [ ! -f SKIP ]; then
		if [ "${CLEAN}" = "1" ] && [ "${USE_QCOW2}" = "0" ] ; then
			if [ -d "${ROOTFS_DIR}" ]; then
				rm -rf "${ROOTFS_DIR}"
			fi
		fi
		if [ -x prerun.sh ]; then
			log "Begin ${STAGE_DIR}/prerun.sh"
			./prerun.sh
			log "End ${STAGE_DIR}/prerun.sh"
		fi
		for SUB_STAGE_DIR in "${STAGE_DIR}"/*; do
			if [ -d "${SUB_STAGE_DIR}" ] &&
			   [ ! -f "${SUB_STAGE_DIR}/SKIP" ]; then
				run_sub_stage
			fi
		done
	fi

	if [ "${USE_QCOW2}" = "1" ]; then 
		unload_qimage
	else
	    # make sure we are not umounting during export-image stage
	    if [ "${USE_QCOW2}" = "0" ] && [ "${NO_PRERUN_QCOW2}" = "0" ]; then
    		unmount "${WORK_DIR}/${STAGE}"
	    fi
	fi

	PREV_STAGE="${STAGE}"
	PREV_STAGE_DIR="${STAGE_DIR}"
	PREV_ROOTFS_DIR="${ROOTFS_DIR}"
	popd > /dev/null
	log "End ${STAGE_DIR}"
}

if [ "$(id -u)" != "0" ]; then
	echo "Please run as root" 1>&2
	exit 1
fi

BASE_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
export BASE_DIR

if [ -f config ]; then
	# shellcheck disable=SC1091
	source config
fi

while getopts "c:" flag
do
	case "$flag" in
		c)
			EXTRA_CONFIG="$OPTARG"
			# shellcheck disable=SC1090
			source "$EXTRA_CONFIG"
			;;
		*)
			;;
	esac
done

term() {
    if [ "${USE_QCOW2}" = "1" ]; then
	log "Unloading image"
	unload_qimage
    fi
}

trap term EXIT INT TERM

export PI_GEN=${PI_GEN:-pi-gen}
export PI_GEN_REPO=${PI_GEN_REPO:-https://github.com/RPi-Distro/pi-gen}

if [ -z "${IMG_NAME}" ]; then
	echo "IMG_NAME not set" 1>&2
	exit 1
fi

export USE_QEMU="${USE_QEMU:-0}"
export IMG_DATE="${IMG_DATE:-"$(date +%Y-%m-%d)"}"
export IMG_FILENAME="${IMG_FILENAME:-"${IMG_DATE}-${IMG_NAME}"}"
export ZIP_FILENAME="${ZIP_FILENAME:-"image_${IMG_DATE}-${IMG_NAME}"}"

export SCRIPT_DIR="${BASE_DIR}/scripts"
export WORK_DIR="${WORK_DIR:-"${BASE_DIR}/work/${IMG_DATE}-${IMG_NAME}"}"
export DEPLOY_DIR=${DEPLOY_DIR:-"${BASE_DIR}/deploy"}
export DEPLOY_ZIP="${DEPLOY_ZIP:-1}"
export LOG_FILE="${WORK_DIR}/build.log"

export HOSTNAME=${HOSTNAME:-raspberrypi}

export FIRST_USER_NAME=${FIRST_USER_NAME:-pi}
export FIRST_USER_PASS=${FIRST_USER_PASS:-raspberry}
export WPA_ESSID
export WPA_PASSWORD
export WPA_COUNTRY
export ENABLE_SSH="${ENABLE_SSH:-0}"

export LOCALE_DEFAULT="${LOCALE_DEFAULT:-en_GB.UTF-8}"

export KEYBOARD_KEYMAP="${KEYBOARD_KEYMAP:-gb}"
export KEYBOARD_LAYOUT="${KEYBOARD_LAYOUT:-English (UK)}"

export TIMEZONE_DEFAULT="${TIMEZONE_DEFAULT:-Europe/London}"

export GIT_HASH=${GIT_HASH:-"$(git rev-parse HEAD)"}

export CLEAN
export IMG_NAME
export APT_PROXY

export STAGE
export STAGE_DIR
export STAGE_WORK_DIR
export PREV_STAGE
export PREV_STAGE_DIR
export ROOTFS_DIR
export PREV_ROOTFS_DIR
export IMG_SUFFIX
export NOOBS_NAME
export NOOBS_DESCRIPTION
export EXPORT_DIR
export EXPORT_ROOTFS_DIR

export QUILT_PATCHES
export QUILT_NO_DIFF_INDEX=1
export QUILT_NO_DIFF_TIMESTAMPS=1
export QUILT_REFRESH_ARGS="-p ab"

# shellcheck source=scripts/common
source "${SCRIPT_DIR}/common"
# shellcheck source=scripts/dependencies_check
source "${SCRIPT_DIR}/dependencies_check"

export NO_PRERUN_QCOW2="${NO_PRERUN_QCOW2:-1}"
export USE_QCOW2="${USE_QCOW2:-1}"
export BASE_QCOW2_SIZE=${BASE_QCOW2_SIZE:-12G}
source "${SCRIPT_DIR}/qcow2_handling"
if [ "${USE_QCOW2}" = "1" ]; then
    NO_PRERUN_QCOW2=1
else
    NO_PRERUN_QCOW2=0
fi

export NO_PRERUN_QCOW2="${NO_PRERUN_QCOW2:-1}"

dependencies_check "${BASE_DIR}/depends"

#check username is valid
if [[ ! "$FIRST_USER_NAME" =~ ^[a-z][-a-z0-9_]*$ ]]; then
	echo "Invalid FIRST_USER_NAME: $FIRST_USER_NAME"
	exit 1
fi

if [[ -n "${APT_PROXY}" ]] && ! curl --silent "${APT_PROXY}" >/dev/null ; then
	echo "Could not reach APT_PROXY server: ${APT_PROXY}"
	exit 1
fi

mkdir -p "${WORK_DIR}"
log "Begin ${BASE_DIR}"

STAGE_LIST=${STAGE_LIST:-${BASE_DIR}/stage*}

for STAGE_DIR in $STAGE_LIST; do
	STAGE_DIR=$(realpath "${STAGE_DIR}")
	run_stage
done

CLEAN=1
for EXPORT_DIR in ${EXPORT_DIRS}; do
	STAGE_DIR=${BASE_DIR}/export-image
	# shellcheck source=/dev/null
	source "${EXPORT_DIR}/EXPORT_IMAGE"
	EXPORT_ROOTFS_DIR=${WORK_DIR}/$(basename "${EXPORT_DIR}")/rootfs
	if [ "${USE_QCOW2}" = "1" ]; then
	    USE_QCOW2=0
	    EXPORT_NAME="${IMG_FILENAME}${IMG_SUFFIX}"
	    echo "------------------------------------------------------------------------"
	    echo "Running export stage for ${EXPORT_NAME}"
	    rm -f "${WORK_DIR}/export-image/${EXPORT_NAME}.img" || true
	    rm -f "${WORK_DIR}/export-image/${EXPORT_NAME}.qcow2" || true
	    rm -f "${WORK_DIR}/${EXPORT_NAME}.img" || true
	    rm -f "${WORK_DIR}/${EXPORT_NAME}.qcow2" || true
	    EXPORT_STAGE=$(basename "${EXPORT_DIR}")
	    for s in $STAGE_LIST; do
		TMP_LIST=${TMP_LIST:+$TMP_LIST }$(basename "${s}")
	    done
	    FIRST_STAGE=${TMP_LIST%% *}
	    FIRST_IMAGE="image-${FIRST_STAGE}.qcow2"

	    pushd "${WORK_DIR}" > /dev/null
	    echo "Creating new base "${EXPORT_NAME}.qcow2" from ${FIRST_IMAGE}"
	    cp "./${FIRST_IMAGE}" "${EXPORT_NAME}.qcow2"

	    ARR=($TMP_LIST)
	    # rebase stage images to new export base
	    for CURR_STAGE in "${ARR[@]}"; do
    		if [ "${CURR_STAGE}" = "${FIRST_STAGE}" ]; then
        	    PREV_IMG="${EXPORT_NAME}"
        	    continue
    		fi
		echo "Rebasing image-${CURR_STAGE}.qcow2 onto ${PREV_IMG}.qcow2"
    		qemu-img rebase -f qcow2 -u -b ${PREV_IMG}.qcow2 image-${CURR_STAGE}.qcow2
    		if [ "${CURR_STAGE}" = "${EXPORT_STAGE}" ]; then
        	    break
    		fi
    		PREV_IMG="image-${CURR_STAGE}"
	    done

	    # commit current export stage into base export image
	    echo "Committing image-${EXPORT_STAGE}.qcow2 to ${EXPORT_NAME}.qcow2"
	    qemu-img commit -f qcow2 -p -b "${EXPORT_NAME}.qcow2" image-${EXPORT_STAGE}.qcow2

	    # rebase stage images back to original first stage for easy re-run
	    for CURR_STAGE in "${ARR[@]}"; do
    		if [ "${CURR_STAGE}" = "${FIRST_STAGE}" ]; then
        	    PREV_IMG="image-${CURR_STAGE}"
        	    continue
    		fi
		echo "Rebasing back image-${CURR_STAGE}.qcow2 onto ${PREV_IMG}.qcow2"
    		qemu-img rebase -f qcow2 -u -b ${PREV_IMG}.qcow2 image-${CURR_STAGE}.qcow2
    		if [ "${CURR_STAGE}" = "${EXPORT_STAGE}" ]; then
        	    break
    		fi
    		PREV_IMG="image-${CURR_STAGE}"
	    done
	    popd > /dev/null

	    mkdir -p "${WORK_DIR}/export-image/rootfs"
	    mv "${WORK_DIR}/${EXPORT_NAME}.qcow2" "${WORK_DIR}/export-image/"
	    echo "Mounting image ${WORK_DIR}/export-image/${EXPORT_NAME}.qcow2 to rootfs ${WORK_DIR}/export-image/rootfs"
	    mount_qimage "${WORK_DIR}/export-image/${EXPORT_NAME}.qcow2" "${WORK_DIR}/export-image/rootfs"

	    CLEAN=0
	    run_stage
	    CLEAN=1
	    USE_QCOW2=1

	else
	    run_stage
	fi 
	if [ "${USE_QEMU}" != "1" ]; then
		if [ -e "${EXPORT_DIR}/EXPORT_NOOBS" ]; then
			# shellcheck source=/dev/null
			source "${EXPORT_DIR}/EXPORT_NOOBS"
			STAGE_DIR="${BASE_DIR}/export-noobs"
			if [ "${USE_QCOW2}" = "1" ]; then
			    USE_QCOW2=0
			    run_stage
			    USE_QCOW2=1
			else
			    run_stage
			fi
		fi
	fi
done

if [ -x postrun.sh ]; then
	log "Begin postrun.sh"
	cd "${BASE_DIR}"
	./postrun.sh
	log "End postrun.sh"
fi

if [ "${USE_QCOW2}" = "1" ]; then
    unload_qimage
fi

log "End ${BASE_DIR}"