#!/bin/bash

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#

builddir=./build

OPENWRTREV="1cd5709e5d9d6e73eb501f1f2840379aa8d171db"
OPENWRTURL="git://git.openwrt.org/15.05/openwrt.git"
PACKAGEREV="ee0bb7b9df86cec0f1d7c27046c50b1fc45b7c4f"
PACKAGEURL="https://github.com/openwrt/packages.git"

## Feed definition [0]: name aka directory, [1]: url, [2]: revision, [3..n]: patches

#official openwrt packages
OPENWRT=(openwrt
         $PACKAGEURL
         $PACKAGEREV)
OPENWRT_PKGS="gpioctl-sysfs libugpio fastd"

## Be careful: FFF uses COMPAT_VERSION 14 at the moment.
## See http://www.open-mesh.org/projects/batman-adv/wiki/Compatversion
BATMAN_ADV=(batman_adv
            https://github.com/freifunk-gluon/packages.git
            b4f04f51d53b151a45f0618eef6d89d32f52dae7)
BATMAN_ADV_PKGS="kmod-batman-adv-legacy"

#official openwrt routing packages
ROUTING=(routing
         https://github.com/openwrt-routing/packages.git
         e870c3373eea80df852d42fac3f40aaffd7a0f58)
ROUTING_PKGS="alfred"

FEEDS=(OPENWRT ROUTING BATMAN_ADV)

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"
            if ! $MYGIT checkout "$COMMITID" ; then
                echo "commitid not found trying to fetch new commits"
                $MYGIT pull && $MYGIT checkout "$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() {
    test -d src || mkdir src
    cd src

    #Get the OpenWrt Core Source for Firmware
    checkout_git openwrt $OPENWRTURL $OPENWRTREV

    test -d packages || mkdir packages
    cd 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 could be stored in known directories like build_patches/$NAME/
            # That way multiple patches for one feed could be supported
            count=3
            while [ "x${FEED[count]}" != "x" ]
            do
                local PATCH=${FEED[count]}
                if [ ! -z "$PATCH" ] ; then
                    echo "Patching $PATCH"
                    git -C "$NAME" am --whitespace=nowarn "$PATCH"
                else
                    echo "Warning, $PATCH not found."
                fi
                count=$(( count + 1 ))
            done
        fi
    done

    cd .. # packages
    cd .. # src
}

prepare() {
    get_source

    test -d $builddir || mkdir $builddir

    /bin/rm -rf "$target"
    cp -a src/openwrt "$target"

    ## generate own feeds.conf
    #this local variable should be globally configure variable used in get_source and here
    local PACKAGEBASE=${PWD}/src/packages
    rm -f "$target"/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" >> "$target"/feeds.conf
    done

    echo "cleaning feeds"
    /bin/rm -rf "$target"/feeds

    "$target"/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 $NAME to available packages"
            "$target"/scripts/feeds install -p "$NAME" "${PACKAGESVAR[@]}"
        fi
    done

    # todo evaluate this with the new openwrt
    # This changes the default behavior of sysupgrade to not save the config 
    patch -p0 -d "$target" -i "$PWD"/build_patches/sysupgrade_no_config_save.patch

    #saves ~200MB for each build
    test -d ./src/dl || mkdir ./src/dl
    ln -s ../../src/dl "$target"/dl

    board_prepare
}

prebuild() {
    #create filesdir for our config
    /bin/rm -rf "$target"/files
    mkdir "$target"/files

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

    arch=$(awk -F= '/^CONFIG_TARGET_BOARD/{print gsub(/"/,"",$2); print $2;}' ./bsp/"$machine"/.config)
    version=$(awk '/^CONFIG_LINUX/ { sub(/CONFIG_LINUX_/,""); sub(/=y/,""); gsub(/_/,"."); print; }' ./bsp/"$machine"/.config)
    test -f ./bsp/"$machine"/.kernelconfig-"$version" && \
        cp ./bsp/"$machine"/.kernelconfig-"$version" \
        "$target"/target/linux/"$arch"/config-"$version"

    board_prebuild

    shopt -s globstar nullglob
    for template in $target/files/**/*.tpl
    do
        echo "Translating $template .."
        $tpl_translate "$template" > "$(dirname "$template")"/"$(basename "$template" .tpl)"
        /bin/rm "$template"
    done

    #insert actual firware version informations into release file
    version=$(git describe --tags --dirty)
    community=$(basename "$(realpath selected_community)" .cfg)

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

build() {
    prebuild

    opath=$(pwd)
    cd "$target"
    cpus=$(grep -c processor /proc/cpuinfo)

    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"

    if [ ! -d bin ]; then
        mkdir bin
    fi

    postbuild
}

config() {
    prebuild

    opath=$(pwd)
    cd "$target"

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

    cd "$opath"

    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 "$1" in
            "openwrt")
                grep '^CON\|^# CON' "$target"/.config | sort > ./bsp/"$machine"/.config
                ;;
            "kernel")
                arch=$(awk -F= '/^CONFIG_TARGET_BOARD/{gsub(/"/,"",$2); print $2;}' ./bsp/"$machine"/.config)
                version=$(awk '/^CONFIG_LINUX/ { sub(/CONFIG_LINUX_/,""); sub(/=y/,""); gsub(/_/,"."); print; }' ./bsp/"$machine"/.config)
                grep '^CON\|^# CON' "$target"/target/linux/"$arch"/config-"$version" | sort > ./bsp/"$machine"/.kernelconfig-"$version"
                ;;
        esac
    fi
}

postbuild() {
    board_postbuild
}

clean() {
    board_clean
    /bin/rm -rf bin $builddir src/openwrt

    # 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
}

buildall() {
    for bsp in $(/bin/ls bsp/*.bsp); do
        ./buildscript selectcommunity "$1"
        ./buildscript selectbsp "$bsp"
        ./buildscript prepare
        ./buildscript build "$2"
    done
}

if [ "$1" != "selectbsp" -a "$1" != "selectcommunity" -a "$1" != "buildall" ]; then
    if [ ! -h selected_bsp ]; then
        echo "Please select a Board-Support-Package using:"
        echo "$0 selectbsp"
        exit
    fi
    if [ ! -h selected_community ]; then
        echo "Please select a community file using:"
        echo "$0 selectcommunity"
        exit
    fi
    echo "Working with $(/bin/ls -l selected_bsp | awk '{ print $11 }') and" \
            "$(/bin/ls -l selected_community | awk '{ print $11 }')"
    . selected_bsp
    tpl_translate=$(awk -F= 'BEGIN{printf("sed")} /^.+$/{gsub("/", "\\/", $0); printf(" -es/\\${%s}/%s/g",$1,$2)}' selected_community)
    echo
fi

case "$1" in
    "selectbsp")
        if [ "$2" = "help" ] || [ "$2" = "" ]; then
            echo "Select a Board-Support-Package:"
            echo
            echo "Usage: $0 $1 bsp"
            echo "available packages:"
            /bin/ls bsp/*.bsp
        else
            if [ ! -f "$2" ]; then
                echo "Could not find $2"
            else
                /bin/rm -rf selected_bsp
                /bin/ln -s "$2" selected_bsp
            fi
        fi
        ;;
    "selectcommunity")
        if [ "$2" = "help" ] || [ "$2" = "" ]; then
            echo "Select a Community-File:"
            echo
            echo "Usage: $0 $1 community.cfg"
            echo "community.cfg: "
            /bin/ls community/*.cfg
        else
            if [ ! -f "$2" ]; then
                echo "Could not find $2"
            else
                /bin/rm -rf selected_community
                /bin/ln -s "$2" selected_community
            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 "Usage: $0 $1"
        else
            prepare
        fi
        ;;
    "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 "Usage: $0 $1 [fast|debug]"
        else
            build "$2"
        fi
        ;;
    "config")
        case "$2" in
            openwrt)
                config openwrt
                ;;
            kernel)
                config kernel
                ;;
            *)
                echo "This open the OpenWRT menuconfig dialog"
                echo
                echo "Usage: $0 $1 openwrt|kernel"
                ;;
        esac
        ;;
    "clean")
        if [ "$2" = "help" ] || [ "$2" = "x" ]; then
            echo "This option cleans all build files."
            echo "$0 $1"
        else
            clean
        fi
        ;;
    "buildall")
        if [ "$2" = "help" ] || [ "$2" = "" ]; then
            echo "This option builds the firmware for all routers of a given community."
            echo "Usage: $0 $1 community.cfg [fast]"
            echo "community.cfg: "
            /bin/ls community/*.cfg
        else
            buildall "$2" "$3"
        fi
        ;;
    *)
        echo "This is the Build Environment Script of the Freifunk Community Franken."
        echo "Usage: $0 command"
        echo "command:"
        echo "  selectcommunity [communityfile]"
        echo "  selectbsp [bsp file]"
        echo "  prepare"
        echo "  config <openwrt|kernel>"
        echo "  build [<fast|debug>]"
        echo "  buildall <community> [<fast>]"
        echo "  clean"
        echo ""
        echo "If you need help to one of these options just type $0 command help"
    ;;
esac