#!/usr/bin/env bats
# Copyright (c) Siemens AG, 2021-2023
#
# Authors:
#  Michael Adler <michael.adler@siemens.com>
#
# This work is licensed under the terms of the GNU GPL, version 2.  See
# the COPYING file in the top-level directory.
#
# SPDX-License-Identifier: GPL-2.0-only
#

setup() {
    # get the containing directory of this file
    # use $BATS_TEST_FILENAME instead of ${BASH_SOURCE[0]} or $0,
    # as those will point to the bats executable's location or the preprocessed
    # file respectively
    DIR="$( cd "$( dirname "$BATS_TEST_FILENAME" )" >/dev/null 2>&1 && pwd )"
    PATH="$DIR/..:$PATH"

    # BATS_TEST_TMPDIR was introduced by BATS 1.4.0, account for older versions
    [ -n "${BATS_TEST_TMPDIR:++}" ] || {
        BATS_TEST_TMPDIR="$BATS_RUN_TMPDIR/test/$BATS_TEST_NUMBER"
        mkdir -p "$BATS_TEST_TMPDIR"
    }
}

create_sample_bgenv() {
    bg_setenv -f "$1" \
        --kernel=C:BOOT:kernel.efi \
        --args=root=/dev/sda \
        --uservar=foo=bar \
        --revision=1
}

verify_envfile() {
    local envfile=$1 ; shift

    local envsize
    envsize=$(wc -c < "$envfile")

    local stored
    stored=$(od -tx4 -j $((envsize - 4)) < "$envfile" | awk 'NF>1 {print $2}')

    local computed
    computed=$(crc32 <(head -c $((envsize - 4)) < "$envfile"))

    [ -n "$stored$computed" -a "$stored" = "$computed" ]
}

resize_envfile() {
    local envfile=$1 ; shift
    local targetsize=$1 ; shift

    # Before resizing, verify that the contents are uncorrupted to
    # avoid truncating the mismatching checksum.

    verify_envfile "$envfile" || return $?

    # Only resize if the target size matches the default size
    # named in the configuration. This is primarily a sanity check
    # because the default size is also encoded in the MD5 checksum
    # validation.

    grep -qF "ENV_MEM_USERVARS=$targetsize" "$BATS_TEST_DIRNAME"/../configure.ac || return $?

    local envsize
    envsize=$(awk '/ ENV_MEM_USERVARS / { print $3 }' config.h) &&
            [ -n "$envsize" ] || {
        echo Expected to find ENV_MEM_USERVARS in $PWD/config.h >&2
        exit 1
    }

    # Compute the difference between the actual size, and the target
    # size. This will be used to expand or contract the payload to match.

    local deltasize=$((targetsize - envsize))
    [[ $deltasize -lt 0 ]] || deltasize=+$deltasize

    # Remove the existing checksum, and then adjust the length
    # to reach the target sizes.

    truncate -s -4 "$envfile" && truncate -s "$deltasize" "$envfile"

    ls -l "$envfile" >&2

    # Install a checksum that matches the content included or
    # excluded to meet the target size.

    local computed
    computed=$(( 0x$(crc32 <(cat "$envfile") ) ))
    echo "$computed" >&2

    local byte0=$(printf %02x $(( (computed >>  0) & 0xff)) )
    local byte1=$(printf %02x $(( (computed >>  8) & 0xff)) )
    local byte2=$(printf %02x $(( (computed >> 16) & 0xff)) )
    local byte3=$(printf %02x $(( (computed >> 24) & 0xff)) )

    printf "%s" "\x$byte0\x$byte1\x$byte2\x$byte3" >&2
    printf "%b" "\x$byte0\x$byte1\x$byte2\x$byte3" >> "$envfile"

    verify_envfile "$envfile"
}

@test "ensure BGENV.DAT backwards compatbility" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"
    create_sample_bgenv "$envfile"

    run bg_printenv -f "$envfile"
    [[ "$output" =  "Values:
in_progress:      no
revision:         1
kernel:           C:BOOT:kernel.efi
kernelargs:       root=/dev/sda
watchdog timeout: 0 seconds
ustate:           0 (OK)

user variables:
foo = bar" ]]

    resize_envfile "$envfile" 131072

    run md5sum "$envfile"
    [[ "$output" =~ ^6ad1dd1d98209a03d7b4fc2d2f16f9ec\s*.* ]]
}

@test "create an empty BGENV.DAT" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"

    run bg_setenv -f "$envfile"
    [[ "$output" = "Output written to $envfile." ]]

    run bg_printenv -f "$envfile"
    [[ "$output" =  "Values:
in_progress:      no
revision:         0
kernel:           
kernelargs:       
watchdog timeout: 0 seconds
ustate:           0 (OK)

user variables:" ]]

    resize_envfile "$envfile" 131072

    run md5sum "$envfile"
    [[ "$output" =~ ^441b49e907a117d2fe1dc1d69d8ea1b0\s*.* ]]
}

@test "modify BGENV, discard existing values" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"

    create_sample_bgenv "$envfile"
    run bg_setenv -f "$envfile" -k C:BOOTNEW:kernel.efi

    run bg_printenv -f "$envfile"
    [[ "$output" = "Values:
in_progress:      no
revision:         0
kernel:           C:BOOTNEW:kernel.efi
kernelargs:       
watchdog timeout: 0 seconds
ustate:           0 (OK)

user variables:" ]]

    resize_envfile "$envfile" 131072

    run md5sum "$envfile"
    [[ "$output" =~ ^15bc40c9feae99cc879cfc55e0132caa\s*.* ]]
}

@test "modify BGENV, preserve existing values" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"

    create_sample_bgenv "$envfile"
    run bg_setenv -f "$envfile" -k C:BOOTNEW:kernel.efi -P

    run bg_printenv -f "$envfile"
    [[ "$output" =  "Values:
in_progress:      no
revision:         1
kernel:           C:BOOTNEW:kernel.efi
kernelargs:       root=/dev/sda
watchdog timeout: 0 seconds
ustate:           0 (OK)

user variables:
foo = bar" ]]

    resize_envfile "$envfile" 131072

    run md5sum "$envfile"
    [[ "$output" =~ ^a24b154a48e1f33b79b87e0fa5eff8a1\s*.* ]]
}

@test "bg_printenv ustate" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"

    create_sample_bgenv "$envfile"
    run bg_printenv "--filepath=$envfile" --output ustate
    [[ "$output" = "Values:
ustate:           0 (OK)" ]]
}

@test "bg_printenv with all fields is the same as omitting fields" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"

    create_sample_bgenv "$envfile"
    expected_output=$(bg_printenv "--filepath=$envfile")
    run bg_printenv "--filepath=$envfile" --output in_progress,revision,kernel,kernelargs,watchdog_timeout,ustate,user
    [[ "$output" = "$expected_output" ]]
}

@test "bg_printenv ustate raw" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"

    create_sample_bgenv "$envfile"
    run bg_printenv "--filepath=$envfile" --output ustate --raw
    [[ "$output" = "USTATE=0" ]]
}

@test "bg_printenv multiple fields raw" {
    local envfile
    envfile="$BATS_TEST_TMPDIR/BGENV.DAT"

    create_sample_bgenv "$envfile"
    run bg_printenv "--filepath=$envfile" --output ustate,kernel,kernelargs --raw
    [[ "$output" = "KERNEL=C:BOOT:kernel.efi
KERNELARGS=root=/dev/sda
USTATE=0" ]]
}