#!/usr/bin/env bash

# Variables declared in dreport, expected to be set before sourcing this file
declare -x name_dir
declare -x dump_size
declare -x dreport_log
declare -x summary_log
declare -x quiet
declare -x verbose

# Source dreport configuration (generated at build time)
if [ -f /usr/share/dreport.d/dreport.conf ]; then
    # shellcheck source=/dev/null
    source /usr/share/dreport.d/dreport.conf
fi

# Set compression flags based on algorithm
case "${DUMP_COMPRESSION:-xz}" in
    xz)
        TAR_COMPRESS_FLAG="-J"
        ARCHIVE_EXT="tar.xz"
        ;;
    gzip)
        TAR_COMPRESS_FLAG="-z"
        ARCHIVE_EXT="tar.gz"
        ;;
    zstd)
        TAR_COMPRESS_FLAG=""
        ARCHIVE_EXT="tar.zst"
        ;;
    *)
        TAR_COMPRESS_FLAG="-J"
        ARCHIVE_EXT="tar.xz"
        ;;
esac

# @brief Create a compressed tar archive
# @param $1 Output file path (without extension)
# @param $2 Source directory (parent dir for -C)
# @param $3 Base name to archive
# @return Sets ARCHIVE_PATH to the created archive path
function create_archive()
{
    local output_base="$1"
    local src_dir="$2"
    local base_name="$3"
    local archive_file="${output_base}.${ARCHIVE_EXT}"

    case "${DUMP_COMPRESSION:-xz}" in
        zstd)
            tar -cf - -C "$src_dir" "$base_name" | zstd > "$archive_file"
            ;;
        *)
            tar ${TAR_COMPRESS_FLAG} -cf "$archive_file" -C "$src_dir" "$base_name"
            ;;
    esac

    ARCHIVE_PATH="$archive_file"
}

# @brief Execute the command and save the output into the dreport
#        packaging, if it is in the user allowed dump size limit.
# @param $1 Command to be executed.
# @param $2 Save file name.
# @param $3 Plugin description used for logging.
function add_cmd_output()
{
    command="$1"
    file_name="$2"
    desc="$3"

    if ! eval "$command" >> "$name_dir/$file_name"; then
        log_error "Failed to collect $desc"
        rm -f "$name_dir/$file_name"
        return 1
    fi

    if check_size "$name_dir/$file_name"; then
        log_info "Collected $desc"
    else
        log_warning "Skipping $desc"
    fi
}

# @brief Copy the file or directory into the dreport packaging,
#        if it is in the user allowed dump size limit.
# @param $1 Copy file or directory name.
# @param $2 Plugin description used for logging.
function add_copy_file()
{
    file_name="$1"
    desc="$2"

    if ! cp -Lr "$file_name" "$name_dir"; then
        log_error "Failed to copy $desc $file_name"
        # file_name is not empty, otherwise cp would have failed
        rm -fr "${name_dir:?}/$file_name"
        return "$RESOURCE_UNAVAILABLE"
    fi
    if check_size "$name_dir/$(basename "$file_name")"; then
        log_info "Copied $desc $file_name"
        return "$SUCCESS"
    else
        log_warning "Skipping copy $desc $file_name"
        return "$RESOURCE_UNAVAILABLE"
    fi
}
# @brief Copy the symbolic link file to the dreport packaging,
#        if it is in the user allowed dump size limit.
# @param $1 symbolic link file name
# @param $2 Plugin description used for logging.
function add_copy_sym_link_file()
{
    file_name="$1"
    desc="$2"

    if ! cp "$file_name" "$name_dir"; then
        log_error "Failed to copy $desc $file_name"
        # file_name is not empty, otherwise cp would have failed
        rm -fr "${name_dir:?}/$file_name"
        return "$RESOURCE_UNAVAILABLE"
    fi
    if check_size "$name_dir/$(basename "$file_name")"; then
        log_info "Copied $desc $file_name"
        return "$SUCCESS"
    else
        log_warning "Skipping copy $desc $file_name"
        return "$RESOURCE_UNAVAILABLE"
    fi
}

# @brief Calculate file or directory compressed size based on input
#        and check whether the size in the allowed size limit.
#        Remove the file or directory from the name_dir
#        if the check fails.
# @param $1 Source file or directory
# @return 0 on success, error code if size exceeds the limit.
# Limitation: compress and tar will have few bytes size difference
function check_size()
{
    source=$1

    #No size check required in case dump_size is set to unlimited
    if [ "$dump_size" = "$UNLIMITED" ]; then
        return 0
    fi

    #get the file or directory size
    if [[ -d $source ]] && [[ -n $source ]]; then
        tar -cf "$source.tar" -C \
            "$(dirname "$source")" "$(basename "$source")"
        size=$(stat -c%s "$source.tar")
        rm "$source.tar"
    else
        size=$(stat -c%s "$source")
    fi

    if [ $((size + cur_dump_size)) -gt "$dump_size" ]; then
        #Exceed the allowed limit,
        #tar and compress the files and check the size
        create_archive "$name_dir" "$(dirname "$name_dir")" "$(basename "$name_dir")"
        size=$(stat -c%s "$ARCHIVE_PATH")
        if [ "$size" -gt "$dump_size" ]; then
            #Remove the the specific data from the name_dir and continue
            rm "$source" "$ARCHIVE_PATH"
            return "$RESOURCE_UNAVAILABLE"
        else
            rm "$ARCHIVE_PATH"
        fi
    fi

    cur_dump_size=$((size + cur_dump_size))
    return "$SUCCESS"
}

# @brief log the error message
# @param error message
function log_error()
{
    echo "$($TIME_STAMP)" "ERROR: $*" >> "$dreport_log"
    if ((quiet != TRUE)); then
        echo "$($TIME_STAMP)" "ERROR: $*" >&2
    fi
}

# @brief log warning message
# @param warning message
function log_warning()
{
    if ((verbose == TRUE)); then
        echo "$($TIME_STAMP)" "WARNING: $*" >> "$dreport_log"
        if ((quiet != TRUE)); then
            echo "$($TIME_STAMP)" "WARNING: $*" >&2
        fi
    fi
}

# @brief log info message
# @param info message
function log_info()
{
    if ((verbose == TRUE)); then
        echo "$($TIME_STAMP)" "INFO: $*" >> "$dreport_log"
        if ((quiet != TRUE)); then
            echo "$($TIME_STAMP)" "INFO: $*" >&1
        fi
    fi
}

# @brief log summary message
# @param message
function log_summary()
{
    echo "$($TIME_STAMP)" "$*" >> "$summary_log"
    if ((quiet != TRUE)); then
        echo "$($TIME_STAMP)" "$*" >&1
    fi
}