#!/bin/bash
# Description: This shell script used to generate patch file
#      Author: guowenxue <guowenxue@gmail.com>
#     Version: 1.0.0  

# this project absolute path
PRJ_PATH=$(cd $(dirname "${BASH_SOURCE[0]}")/.. && pwd)

# top project absolute path
TOP_PATH=$(realpath $PRJ_PATH/..)

# config file path
CONF_FILE=$TOP_PATH/config.json

# download taballs path
TARBALL_PATH=$PRJ_PATH/tarballs

# shell script will exit once get command error
#set -e

#+-------------------------+
#| Shell script functions  |
#+-------------------------+

function pr_error() {
    echo -e "\033[40;31m $1 \033[0m"
}

function pr_warn() {
    echo -e "\033[40;33m $1 \033[0m"
}

function pr_info() {
    echo -e "\033[40;32m $1 \033[0m"
}

# decompress a packet to destination path
function do_unpack()
{
    tarball=$1
    dstpath=`pwd`

    if [[ $# == 2 ]] ; then
        dstpath=$2
    fi

    pr_info "decompress $tarball => $dstpath"

    mkdir -p $dstpath
    case $tarball in
        *.tar.gz)
            tar -xzf $tarball -C $dstpath
            ;;

        *.tar.bz2)
            tar -xjf $tarball -C $dstpath
            ;;

        *.tar.xz)
            tar -xJf $tarball -C $dstpath
            ;;

        *.tar.zst)
            tar -I zstd -xf $tarball -C $dstpath
            ;;

        *.tar)
            tar -xf $tarball -C $dstpath
            ;;

        *.zip)
            unzip -qo $tarball -d $dstpath
            ;;

        *)
            pr_error "decompress Unsupport packet: $tarball"
            return 1;
            ;;
    esac
}

# parser configure file and export environment variable
function export_env()
{
    export SRC=$(basename $1)

    export BOARD=`jq -r ".bsp.board" $CONF_FILE | tr 'A-Z' 'a-z'`
    export BSP_VER=`jq -r ".bsp.version" $CONF_FILE | tr 'A-Z' 'a-z'`
    export CROSS_COMPILE=`jq -r ".bsp.crosstool" $CONF_FILE`
    export PATCH=$SRC-$BSP_VER.patch
}

function do_clean()
{
	cd $SRC
	make mrproper CROSS_COMPILE=${CROSS_COMPILE} 
	cd $PRJ_PATH
}

function do_patch()
{
    if [ ! -d $PRJ_PATH/$SRC ] ;  then
        pr_error "\nERROR: source code $SRC not exist, exit now\n\n"
        exit;
    fi


	# rename new source code
	mv ${SRC} ${SRC}-${BOARD}

	# decompress orignal soruce code packet
	do_unpack ${TARBALL_PATH}/${SRC}.tar.xz

    pr_info "generate patch file $PATCH"

	# generate patch file
	diff -Nuar ${SRC} ${SRC}-${BOARD}  > $PATCH

	# remove orignal soruce code
	rm -rf ${SRC}

	# recover new source code
	mv ${SRC}-${BOARD} ${SRC} 
}

if [ $# != 1 ] ; then
    pr_info "$0 usage example:"
    pr_info "$0 at91bootstrap"
    pr_info "$0 u-boot-at91"
    exit
fi

export_env $1

do_clean

do_patch