#!/bin/bash -ex
#
# hackish script based on http://linux-sunxi.org/Building_on_Debian to
# create a basic debian image for the olinuxino a20 micro
# (s.a. http://linux-sunxi.org/A20-OLinuXino)
#
# This script is intended to be used in a clean debian/wheezy virtual
# machine maybe cross-compiling (tested on amd64 using kvm) or to run
# a self-hosted native compile (tested using network block device via
# xnbd-client but didn't work for me yet - if it works for you please
# report it!)
#
# latest version at:
# http://karme.de/olimex/olinuxino-a20-micro-image-builder
#
# Notes:
# - has to be run as root and is somewhat dangerous
# - you need around 15G free disk space
# - downloads code from github
# - at the moment uses emdebian for cross compilation tool chain
#   (if cross-compiling)
# - script must be installed in path as it calls itself
# - root password is root !
# - consoles use auto-login (no password!)
# - ideally the boards would be supported in mainline kernel
#   s.a. http://linux-sunxi.org/Linux_mainlining_effort
# - ideally one would add support for the board (and similar boards)
#   to the debian installer and/or freedom-maker / freedombox
# - maybe you want to take a look at more general Board Support
#   Package (BSP) at http://linux-sunxi.org/BSP

# keep the previous empty line for the help sub-command

# This version has been updated and modified for use with the
# LulzBot Easy TAZ Mini 3D Printer by Aleph Objects, Inc.
#
# Copyright (c) 2013 Jens Thiele <karme@karme.de>
# Copyright (c) 2014 Aleph Objects, Inc. <code@alephobjects.com>
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# 3. Neither the name of the authors nor the names of its contributors
#    may be used to endorse or promote products derived from this
#    software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
# TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

# use ccache (note: we install ccache in setup)
export PATH=/usr/lib/ccache:$PATH
# debconf should not ask questions
export DEBIAN_FRONTEND=noninteractive

TARGETSUITE="wheezy"

function cross-compile-options {
    [ "$(dpkg-architecture -qDEB_HOST_ARCH)" = "armhf" ] \
	|| echo "CROSS_COMPILE=arm-linux-gnueabihf-"
}

function cross-compile? {
    test -n "$(cross-compile-options)"
}

# use gcc 4.7 (note: self-hosted build didn't work otherwise)
# todo: shouldn't we set AS,LD,CPP... too then?
COMPILE_OPTIONS="$(cross-compile-options) CC=arm-linux-gnueabihf-gcc-4.7"

function setup-cross {
    # for now use emdebian cross compilation tool chain
    # todo: wasn't there a debian package to build cross compilation
    # tool chains?!
    cat <<EOF > /etc/apt/sources.list.d/emdebian.list
deb http://www.emdebian.org/debian/ $(lsb_release -c -s) main
deb http://www.emdebian.org/debian/ sid main
EOF
    apt-get -y install emdebian-archive-keyring qemu-user-static
    apt-get update
    apt-get -y install gcc-4.7-arm-linux-gnueabihf
}

function setup {
    # todo:
    # - skip squid installation if http_proxy is set? (note: using
    #   squid instead of squid3 because squid3 didn't work well)
    apt-get -y install build-essential libncurses5-dev u-boot-tools \
    debootstrap git binfmt-support libusb-1.0-0-dev \
    pkg-config dosfstools util-linux squid ccache sudo

    if cross-compile?; then
	setup-cross
    else
	apt-get -y install gcc-4.7
    fi

    # create user for download/compilation
    if ! id imagebuilder; then
	addgroup --system imagebuilder
	adduser --system --ingroup imagebuilder imagebuilder
    fi

    sudo -E -H -u imagebuilder -s /bin/sh -c \
	"cd ~ ; olinuxino-a20-micro-image-builder user-setup"
}

function make-image {
    local CARD="$1"
    test -z "$1" && CARD="olinuxino-a20-micro-debian.img"

    local LOCKDIR=/run/olinuxino-a20-micro-image-builder
    mkdir $LOCKDIR

    sudo -E -H -u imagebuilder -s /bin/sh -c \
	"cd ~ ; olinuxino-a20-micro-image-builder user-compile"

    # total image size in bytes (for now use <4GB)
    local SIZE=3600000000
    local KERNELTREEDIR=~imagebuilder/linux-sunxi

    # use local http proxy (note: we install squid in setup)
    http_proxy=${http_proxy:-http://localhost:3128}
    export http_proxy

    apt-get install dosfstools util-linux

    # remove the image file if it exists
    # (safety measure in case parts are still mounted)
    test -f $CARD && rm -v $CARD

    # create sparse image file
    dd if=/dev/zero of=$CARD bs=1 count=1 seek=$((SIZE-1))

    # create partitions (for now use separate boot and root)
    local RFSSIZE=$((((SIZE/512)-34816)/(1024*1024)*(1024*1024)))
    cat <<EOF|sfdisk -q -L --no-reread $CARD
# partition table of /dev/mmcblk0
unit: sectors

/dev/mmcblk0p1 : start=     2048, size=    32768, Id=83
/dev/mmcblk0p2 : start=    34816, size= $RFSSIZE, Id=83
/dev/mmcblk0p3 : start=        0, size=        0, Id= 0
/dev/mmcblk0p4 : start=        0, size=        0, Id= 0
EOF
    # print it for debugging
    sfdisk -q -L --no-reread -d $CARD

    LOOPDEV=$(losetup -f --show $CARD)
    # read partition table on loop device
    partx -a $LOOPDEV
    # create fs for boot (for now use vfat as i am not sure u-boot can
    # read uEnv.txt from ext2/ext4)
    mkfs.vfat -n boot -I ${LOOPDEV}p1
    # create root fs
    mkfs.ext4 -L debian_armhf ${LOOPDEV}p2
    sync

    # populate boot
    mkdir $LOCKDIR/boot
    mount ${LOOPDEV}p1 $LOCKDIR/boot
    cp $KERNELTREEDIR/arch/arm/boot/uImage $LOCKDIR/boot
    cp -v ~imagebuilder/sunxi-boards/sys_config/a20/*.{fex,bin} \
	$LOCKDIR/boot
    # choose default fex/script
    cp -v $LOCKDIR/boot/a20-olinuxino_micro-lcd7.bin \
	$LOCKDIR/boot/script.bin
    cat <<EOF > $LOCKDIR/boot/README
debian/$TARGETSUITE image created using
olinuxino-a20-micro-image-builder.

Default setup is for usage with 7" LCD display at the moment.

If you want to test hdmi copy a20-olinuxino_micro.bin to script.bin
first! Additionally you might have to pass some kernel arguments.  For
my iiyama lcd connected via HDMI<->DVI adapter I put the following
line in uEnv.txt:
extraargs=hdmi.audio=0 disp.screen0_output_mode=1280x1024p60
EOF
    # we can pass additional kernel arguments via uEnv.txt
    # example: disable console blank on idle
    #    cat <<EOF > $LOCKDIR/boot/uEnv.txt
    #extraargs=consoleblank=0
    #EOF
    umount $LOCKDIR/boot
    sync
    rmdir $LOCKDIR/boot

    # populate root fs

    # select debian mirrors to fetch packages from
    # todo: maybe extract from localhost?! detect fastest?!
    # (use netselect? apt-spy?)
    #MIRROR="http://ftp.debian.org/debian/"
    local MIRROR="http://mirrors.kernel.org/debian/"

    # (todo: maybe do not recreate root fs each time?)
    mkdir -p $LOCKDIR/chroot-armhf
    mount ${LOOPDEV}p2 $LOCKDIR/chroot-armhf
    pushd $LOCKDIR/chroot-armhf
    # todo: maybe use multistrap like freedom-maker does?
    # see also: https://www.freedomboxfoundation.org/code/
    # or maybe use qemu-debootstrap?
    debootstrap --foreign --arch armhf $TARGETSUITE . $MIRROR
    cp /usr/bin/qemu-arm-static usr/bin
    LC_ALL=C LANGUAGE=C LANG=C chroot . /debootstrap/debootstrap --second-stage
    LC_ALL=C LANGUAGE=C LANG=C chroot . dpkg --configure -a
    echo -e 'root\nroot'|chroot . passwd
    echo A20 > etc/hostname
    sed -i 's,127.0.0.1\tlocalhost$,127.0.0.1\tlocalhost A20,' etc/hosts
    cat <<EOF >> etc/network/interfaces
# The primary network interface
allow-hotplug eth0
iface eth0 inet dhcp

# wlan examples:
# see also:
# /usr/share/doc/wireless-tools/README.Debian

# WPA AP
# allow-hotplug wlan0
# iface wlan0 inet dhcp
#      wpa-ssid yourssid
#      wpa-psk passphrase

# ad-hoc wlan
# iface wlan0 inet static
#      address 192.168.42.1
#      network 192.168.42.0
#      netmask 255.255.255.0
#      broadcast 192.168.42.255
#      wireless-essid Home
#      wireless-mode ad-hoc
EOF
    cat <<EOF > etc/apt/sources.list
deb $MIRROR $TARGETSUITE main contrib non-free
deb http://security.debian.org/ $TARGETSUITE/updates main contrib non-free
EOF
    # prepare to run some stuff on first boot
    cat <<EOF > etc/rc.local
#!/bin/bash -xe
if test -f /etc/force-first-run; then
	/usr/local/sbin/first-run
fi
exit 0
EOF
    touch etc/force-first-run
    # script run on first boot
    # todo: maybe resize parition/filesystem to use all space
    # available
    cat <<EOF > usr/local/sbin/first-run
#!/bin/bash -xe
# recreate ssh keys
rm -vf /etc/ssh/ssh_host_*
dpkg-reconfigure openssh-server
rm -vf /etc/force-first-run
EOF
    chmod +x usr/local/sbin/first-run
    (
	export LC_ALL=C
	export LANGUAGE=C
	export LANG=C
	RETRY=3
	# todo: delay ssh key generation until first boot
	while ! ( chroot . apt-get update && \
	    chroot . apt-get -y upgrade && \
	    chroot . apt-get -y install \
	    nvi emacs23-nox w3m-el-snapshot \
	    i2c-tools fbset console-tools \
	    util-linux task-ssh-server locales openssh-client input-utils \
	    build-essential less git magit bash-completion \
	    command-not-found psmisc sysstat strace xnbd-client \
	    gauche gauche-c-wrapper \
	    xserver-xorg xserver-xorg-video-fbdev sawfish x11-xserver-utils \
	    xinit xterm \
	    conkeror \
	    wireless-tools wpasupplicant \
	    firmware-linux firmware-realtek firmware-ralink \
	    alsa-utils \
	    avahi-daemon \
	    debian-goodies \
	    imagemagick gqview ); do
	    sleep 1
	    RETRY=$[RETRY-1]
	done
    )

    rm -v etc/resolv.conf
    # auto-login
    sed -i 's,1:2345:respawn:/sbin/getty 38400 tty1,1:2345:respawn:/sbin/getty -a root 38400 tty1\
# show pictures instead of login prompt \
# 1:2345:respawn:/usr/local/bin/showpics,' \
	etc/inittab

    # serial auto-login
    echo T0:2345:respawn:/sbin/getty -L -a root ttyS0 115200 vt100 \
	>> etc/inittab
    make -C $KERNELTREEDIR INSTALL_MOD_PATH=`pwd` ARCH=arm \
	${COMPILE_OPTIONS} modules_install
    cp -v "$(which olinuxino-a20-micro-image-builder)" usr/local/bin
    cat <<"EOF" > usr/local/bin/showpics
#!/bin/bash
# really ugly hack to show pictures on framebuffer
W=$(($(cat /sys/class/graphics/fb0/stride)/4))
H=$(fbset|grep ^mode|sed s,'mode "\([0-9]\+\)x\([0-9]\+\)-\([0-9]\+\)",\2,')
echo 0 > /sys/devices/virtual/graphics/fbcon/cursor_blink
cd /home
while true; do
    find -iname "*.jpg" \
         -exec sh -c \
               'convert "$1" -resize '${W}x${H}' \
                        -background black \
                        -gravity center \
                        -extent '${W}x${H}' BGRA:/dev/fb0 ; \
                echo 0 > /sys/class/graphics/fb0/blank ; \
                sleep 1' \
               -- \{\} \;
done
EOF
    chmod +x usr/local/bin/showpics
    # announce sftp via avahi (for simple access via gnome/nautilus)
    cp -v usr/share/doc/avahi-daemon/examples/sftp-ssh.service  etc/avahi/services/
    rm -v etc/avahi/services/udisks.service
    popd
    umount $LOCKDIR/chroot-armhf
    sync
    rmdir  $LOCKDIR/chroot-armhf

    # cleanup
    # todo: should also happen in error case (maybe use trap or use a
    # better language)

    partx -d $LOOPDEV
    dd if=~imagebuilder/u-boot-sunxi/u-boot-sunxi-with-spl.bin \
	of=$LOOPDEV bs=1024 seek=8
    sync
    # wtf
    RETRY="10"
    while [ $RETRY -gt 0 ] && ! losetup -d $LOOPDEV; do
	sync
	sleep 1
	RETRY=$[RETRY-1]
    done
    rmdir $LOCKDIR
    echo "Your image $CARD is ready."
}

function assert-not-root {
    if [ "$(whoami)" = "root" ]; then
	echo do not run as root
	exit 1
    fi
}

function user-setup {
    assert-not-root
    local r
    for r in sunxi-tools u-boot-sunxi; do
	test -d "${r}" || \
	    git clone "https://github.com/linux-sunxi/${r}.git"
    done
    test -d sunxi-boards || \
	git clone "https://github.com/karme/sunxi-boards.git"
    # todo: use --single-branch ?
    test -d linux-sunxi || \
	git clone "https://github.com/karme/linux-sunxi.git" -b stage/sunxi-3.4
}

function user-compile {
    assert-not-root
    # u-boot
    pushd u-boot-sunxi
    # Current git master is broken, grab earlier branch
    git checkout v2013.10-sunxi
    make distclean ${COMPILE_OPTIONS}
    make A20-OLinuXino_MICRO ${COMPILE_OPTIONS}
    popd
    # kernel
    pushd linux-sunxi
    make ARCH=arm mrproper
    cp -v arch/arm/configs/sun7i_defconfig .config
    # todo: oldconfig not supported?
    make ARCH=arm oldconfig
    make ARCH=arm ${COMPILE_OPTIONS} -j $(nproc) uImage
    make ARCH=arm ${COMPILE_OPTIONS} -j $(nproc) modules
    popd
    # sunxi-tools (todo: maybe make clean on update)
    make -C sunxi-tools
    for f in a20-olinuxino_micro.fex a20-olinuxino_micro-lcd7.fex; do
	./sunxi-tools/fex2bin \
	    sunxi-boards/sys_config/a20/"$f" \
	    sunxi-boards/sys_config/a20/"${f%*.fex}.bin"
    done
}

function update {
    sudo -E -H -u imagebuilder -s /bin/sh -c \
	"cd ~ ; olinuxino-a20-micro-image-builder user-update"
}

function user-update {
    assert-not-root
    local r
    # only update kernel for now
    # for r in sunxi-tools sunxi-boards u-boot-sunxi linux-sunxi; do
    for r in linux-sunxi; do
	pushd $r
	git pull
	git status
	popd
    done
}

function help() {
    echo "Usage $0 [setup|make-image|update]"
    sed '/^$/q' < $0|tail -n +2|cut -c 2-
    cat <<EOF
sub-commands:
setup       prepare environment for image build
make-image  build image
update      update from git remotes

Example:
$0 setup
# ... wait for ca. 30 min (depends mainly on your network connection) ...
$0 make-image
# ... wait for ca. 45 min (depending on network and cpu) ...
# test your new image (dd to sd card)
# something didn't work and someone fixed it
$0 update
# ... wait few seconds ...
$0 make-image
# ... wait for ca. 20 min (depending on storage and cpu) ...
# test your image again and repeat
EOF
    exit 1
}

CMD="$1"
test -z "$CMD" && help
shift
case "$CMD" in
    setup)
	setup "$@"
	;;
    make-image)
	make-image "$@"
	;;
    user-setup)
	user-setup "$@"
	;;
    user-compile)
	user-compile "$@"
	;;
    update)
	update "$@"
	;;
    user-update)
	user-update "$@"
	;;
    test-run)
	time $0 setup
	time $0 make-image
	time $0 update
	time $0 make-image
	;;
    *)
	help
	;;
esac