#!/bin/bash
# SPDX-License-Identifier: GPL-3.0-or-later

set -e
set -o pipefail

builddir=./build

# OpenWrt: package hashes correspond to core repo version
OPENWRTREV="v21.02.2"
PACKAGEREV="b0ccc356900f6e1e1dc613d0ea980d5572f553dd"
ROUTINGREV="10d3ffd8b30186b49538167bac1fa1bf9c88f860"

# Gluon packages: master from 2020-02-04
GLUONREV="12e41d0ff07ec54bbd67a31ab50d12ca04f2238c"

OPENWRT_PKGS="gpioctl-sysfs libugpio fastd haserl micrond mtr bmon"
ROUTING_PKGS="kmod-batman-adv batctl alfred babeld"
GLUON_PKGS="simple-tc uradvd"

FFF_VARIANTS="node layer3"

OPENWRTURL="https://git.freifunk-franken.de/mirror/openwrt.git"

## Feed definition [0]: name aka directory, [1]: url, [2]: revision

#official openwrt packages
OPENWRT=(openwrt
         https://git.freifunk-franken.de/mirror/openwrt-packages.git
         $PACKAGEREV)

#gluon packages
GLUON=(gluon
       https://github.com/freifunk-gluon/packages.git
       $GLUONREV)

#official openwrt routing packages
ROUTING=(routing
         https://git.freifunk-franken.de/mirror/openwrt-routing.git
         $ROUTINGREV)

FFF=(fff)
FFF_PKGS="-a"

FEEDS=(OPENWRT ROUTING GLUON FFF)

# Disable dnsmasq and other useless stuff
export DEVICE_TYPE=

checkout_git(){
    local DIRECTORY=$1
    local REPO_URL=$2
    local COMMITID=$3

    local MYGIT="git -C $DIRECTORY"
    echo "checking out $REPO_URL to $DIRECTORY in version $COMMITID"
    if [ -d "$DIRECTORY" ]; then
        if $MYGIT remote -v | grep -q "$REPO_URL" ; then
            echo "Right remote detected"
            # Remove untracked files
            $MYGIT clean -f -d
            # Select desired commit and remove local changes (-f)
            if ! $MYGIT checkout -f "$COMMITID" ; then
                echo "commitid not found trying to fetch new commits"
                $MYGIT fetch --all && $MYGIT checkout "$COMMITID"
            fi
        else
            echo "wrong remote or not an git repo at all -> deleting whole directory"
            /bin/rm -rf "$DIRECTORY"
            #needs to be without -C!!!
            git clone "$REPO_URL" "$DIRECTORY"
            $MYGIT checkout "$COMMITID"
        fi
    else
        echo "We need to do a fresh checkout"
        #needs to be without -C!!!
        git clone "$REPO_URL" "$DIRECTORY"
        $MYGIT checkout "$COMMITID"
    fi
}

get_source() {
    #Get the OpenWrt main repo
    checkout_git $builddir $OPENWRTURL $OPENWRTREV

    test -d src/packages || mkdir -p src/packages
    cd src/packages

    #checkout needed package feeds
    for FEEDVAR in "${FEEDS[@]}" ; do
        FEED="${FEEDVAR}[@]"
        FEED=("${!FEED}")

        local NAME=${FEED[0]}
        local URL=${FEED[1]}
        local REV=${FEED[2]}

        if [ -n "$URL" ] && [ -n "$REV" ]; then
            checkout_git "$NAME" "$URL" "$REV"

            # Patches for feeds are stored in known directories like feed_patches/$NAME/
            for PATCH in $(ls ../../feed_patches/${NAME}/*.patch 2>/dev/null); do
                if [ -s "$PATCH" ] ; then
                    echo "Applying $PATCH"
                    git -C "$NAME" am --whitespace=nowarn "../$PATCH"
                else
                    echo "Empty patch $PATCH ignored."
                fi
            done
        fi
    done

    cd .. # packages
    cd .. # src
}

patch_target() {
    for patch in $(ls "$PWD"/build_patches/openwrt/*.patch 2>/dev/null); do
        echo "Applying $patch:"
        patch --no-backup-if-mismatch -p1 -d "$builddir" -i "$patch"
    done
}

prepare() {
    get_source

    patch_target

    # apply variant to ensure the included file "variant.mk"
    # exists in builddir.
    apply_variant

    update_feeds
}

apply_variant() {
    # set the variant for this build
    export FFF_VARIANT=$(cat selected_variant)
    # force the reevaluation of this Makefile to make note of the new variant
    touch ./src/packages/fff/fff/Makefile
}

update_feeds() {
    ## generate own feeds.conf
    #this local variable should be globally configure variable used in get_source and here
    local PACKAGEBASE=${PWD}/src/packages
    rm -f "$builddir"/feeds.conf
    for FEEDVAR in "${FEEDS[@]}" ; do
        FEED="${FEEDVAR}[@]"
        FEED=("${!FEED}")
        local NAME=${FEED[0]}
        echo "adding $NAME to package feeds"
        echo src-link "$NAME" "$PACKAGEBASE"/"$NAME" >> "$builddir"/feeds.conf
    done

    echo "cleaning feeds"
    "$builddir"/scripts/feeds clean

    "$builddir"/scripts/feeds update

    for FEEDVAR in "${FEEDS[@]}" ; do
        FEED="${FEEDVAR}[@]"
        FEED=("${!FEED}")
        local NAME=${FEED[0]}
        local PACKAGESVAR="${FEEDVAR}_PKGS"
        PACKAGESVAR="${PACKAGESVAR}[@]"
        PACKAGESVAR=(${!PACKAGESVAR})

        if [[ -n "${PACKAGESVAR[@]}" ]] ; then
            echo "adding ${PACKAGESVAR[*]} from feed $NAME to available packages"
            "$builddir"/scripts/feeds install -p "$NAME" "${PACKAGESVAR[@]}"
        fi
    done
}

prebuild() {
    apply_variant

    #create filesdir for our config
    /bin/rm -rf "$builddir"/files
    mkdir "$builddir"/files

    cp -r ./bsp/default/root_file_system/* "$builddir"/files/
    cp ./bsp/"$machine"/.config "$builddir"/.config

    #insert actual firware version informations into release file
    variant=$(cat selected_variant)
    version=$(git describe --tags --dirty)
    if [ 0 -ne $? ]; then
        version=$(git log -1 --pretty=format:%h)
    fi
    if [ -n "$variant" ]; then
        version="$variant-$version"
    fi

    {
        echo "FIRMWARE_VERSION=\"$version\""
        echo "VARIANT=\"$variant\""
        echo "BUILD_DATE=\"build date: $(date)\""
        echo "OPENWRT_CORE_REVISION=\"${OPENWRTREV}\""
        echo "OPENWRT_FEEDS_PACKAGES_REVISION=\"${PACKAGEREV}\""
    } > "$builddir"/files/etc/firmware_release

    opath=$(pwd)
    cd "$builddir"
    make defconfig
    cd "$opath"
}

build() {
    prebuild

    rm_firmware

    opath=$(pwd)
    cd "$builddir"
    cpus=$(nproc)

    case "$1" in
        "debug")
            make V=99
            ;;
        "fast")
            ionice -c 2 -- nice -n 1 -- make -j $((cpus*2))
            ;;
        *)
            ionice -c 3 -- nice -n 10 -- make -j $((cpus+1))
            ;;
    esac

    cd "$opath"

    cp_firmware
}

config() {
    prebuild

    opath=$(pwd)
    cd "$builddir"

    case "$1" in
        "openwrt")
            make menuconfig
            ;;
    esac

    save=""
    until [ "$save" = "y" -o "$save" = "n" ]; do
        echo "Do you want to save the generated config? (y/n)"
        read save
    done

    if [ "$save" = "y" ]; then
        case "$1" in
            "openwrt")
                echo "# Generated using \"./buildscript config openwrt\"." > "$opath"/bsp/"$machine"/.config
                echo "# Do no edit manually" >> "$opath"/bsp/"$machine"/.config
                echo "#" >> "$opath"/bsp/"$machine"/.config
                ./scripts/diffconfig.sh >> "$opath"/bsp/"$machine"/.config
                ;;
        esac
    fi

    cd "$opath"
}

rm_firmware() {
    [ -n "$subtarget" ] || subtarget="generic"

    rm -rf $builddir/bin/targets/${chipset}/${subtarget}
}

cp_firmware() {
    [ -n "$subtarget" ] || subtarget="generic"

    mkdir -p "bin/$variant"

    imagesrcpath="$builddir/bin/targets/${chipset}/${subtarget}"
    imagedestpath="./bin/$variant"

    for image in ${images[@]}; do
        # This assumes the set of images names is given with a wildcard
        fullsrcpattern=$imagesrcpath/$image
        if ! ls $fullsrcpattern >/dev/null 2>/dev/null; then
            echo "Warning: $image not found."
            continue
        fi
        for f in $fullsrcpattern; do
            filename_build=${f##*/}
            filename_build=${filename_build//openwrt/fff-${version}}
            filename_build=${filename_build//squashfs-/}
            filename_build=${filename_build//${chipset}-/}
            filename_build=${filename_build//${subtarget}-/}
            cp "$f" "$imagedestpath/$filename_build"
        done
    done
}

buildrelease() {
    if [ "$1" = "all" ];then
        all=true
    elif [ "$1" = "fast" ];then
        fast=fast
    fi

    if [ "$2" = "all" ];then
        all=true
    elif [ "$2" = "fast" ];then
        fast=fast
    fi

    if [ $all ]; then
        buildall $fast
    else
        build $fast
    fi

    cd bin/$variant
    for binary in *.bin *.img *.tar; do
        md5sum "$binary" > ./"$binary".md5
        sha256sum "$binary" > ./"$binary".sha256
    done
    echo -e "VERSION:$version" > release.nfo
    cd ../..
}

clean() {
    /bin/rm -rf bin $builddir

    # remove downloaded package feeds
    for FEEDVAR in "${FEEDS[@]}" ; do
        FEED="${FEEDVAR}[@]"
        FEED=("${!FEED}")

        local NAME=${FEED[0]}
        local URL=${FEED[1]}
        local REV=${FEED[2]}

        if [ -n "$URL" ] && [ -n "$REV" ]; then
            /bin/rm -rf src/packages/"$NAME"
        fi
    done
}

loadBSP()
{
    localbsppath=$(/bin/ls -l selected_bsp | awk '{ print $11 }')

    if ! [ -s selected_bsp ]; then
        echo "Error: $localbsppath does not exist. Aborting ..."
        exit 1
    fi

    echo "Working with $localbsppath"
    . selected_bsp
    machine=$(basename $(realpath selected_bsp) .bsp)
}

loadVariant()
{
    echo "Working with build variant \"$(cat selected_variant)\""
}

setVariant()
{
    echo "$1" > selected_variant
}

setBSP()
{
    /bin/rm -rf selected_bsp
    /bin/ln -s "$1" selected_bsp
    loadBSP
}

buildall() {
    for bsp in $(/bin/ls bsp/*.bsp); do
        setBSP "$bsp"
        build "$1"
    done
}

if [ "$(/usr/bin/id -u)" -eq 0 ]; then
    echo "don't run buildscript as root"
    exit 1
fi

if [ "$1" != "selectbsp" -a "$1" != "selectvariant" ]; then
    if [ ! -h selected_bsp ]; then
        echo "Please select a Board-Support-Package using:"
        echo "$0 selectbsp"
        exit
    fi
    if [ ! -f selected_variant ]; then
        echo "Please select a build variant using:"
        echo "$0 selectvariant"
        exit
    fi
    loadBSP
    loadVariant
    echo
fi

case "$1" in
    "selectbsp")
        if [ "$2" = "help" ] || [ "$2" = "" ]; then
            echo "Select a Board-Support-Package:"
            echo
            echo "Usage: $0 $1 <bsp-file>"
            echo "available packages:"
            /bin/ls bsp/*.bsp
            echo
        else
            if [ ! -f "$2" ]; then
                echo "Could not find $2"
            else
                setBSP "$2"
            fi
        fi
        ;;
    "selectvariant")
        if [ "$2" = "help" ] || [ "$2" = "" ]; then
            echo "Select a build variant:"
            echo
            echo "Usage: $0 $1 <name of variant>"
            echo "available variants: $FFF_VARIANTS"
            echo
        else
            if ! echo "$FFF_VARIANTS" | grep -q "\b$2\b"; then
                echo "Could not find variant $2"
            else
                setVariant $2
            fi
        fi
        ;;
    "prepare")
        if [ "$2" = "help" ] || [ "$2" = "x" ]; then
            echo "This option fetches the sources for the images and configurates the build so that it can be compiled"
            echo
            echo "Usage: $0 $1"
            echo
        else
            prepare
        fi
        ;;
    "updatefeeds")
        update_feeds
        ;;
    "build")
        if [ "$2" = "help" ] || [ "$2" = "x" ]; then
            echo "This option compiles the firmware"
            echo "Normaly the build uses lower IO and System priorities, "
            echo "you can append \"fast\" option, to use normal user priorities"
            echo
            echo "Usage: $0 $1 [fast|debug]"
            echo
        else
            build "$2"
        fi
        ;;
    "config")
        case "$2" in
            openwrt)
                config openwrt
                ;;
            *)
                echo "This open the OpenWrt menuconfig dialog"
                echo
                echo "Usage: $0 $1 openwrt"
                echo
                ;;
        esac
        ;;
    "clean")
        if [ "$2" = "help" ] || [ "$2" = "x" ]; then
            echo "This option cleans all build files."
            echo
            echo "Usage: $0 $1"
            echo
        else
            clean
        fi
        ;;
    "buildall")
        if [ "$2" = "help" ]; then
            echo "This option builds the firmware for all routers."
            echo
            echo "Usage: $0 $1 [fast]"
            echo
        else
            buildall "$2"
        fi
        ;;
    "release")
        if [ "$2" = help ]; then
            echo "This option builds the firmware for a given board. It also creates hash sums and a the file release.nfo"
            echo
            echo "Usage: $0 $1 [all] [fast]"
            echo
        else
            buildrelease "$2" "$3"
        fi
        ;;
    *)
        echo "This is the Build Environment Script of the Freifunk Community Franken."
        echo
        echo "Usage: $0 command"
        echo "command:"
        echo "  selectbsp <bsp-file>"
        echo "  selectvariant <name of variant>"
        echo "  prepare"
        echo "  updatefeeds"
        echo "  config openwrt"
        echo "  build [fast|debug]"
        echo "  buildall [fast]"
        echo "  release [all] [fast]"
        echo "  clean"
        echo ""
        echo "If you need help to one of these options just type: $0 <command> help"
        echo
    ;;
esac