configure

#!/bin/sh
set -e

CONFIG_FILE=$SNAP_DATA/config

## remove option from file. Do not fail if config file doesn't exist
_remove_opt_from_file() {
    # Note that we don't use sed -i as it's using fchown32 denied
    # by seccomp profile.
    sed "/^$1=/d" $CONFIG_FILE 2>/dev/null >${CONFIG_FILE}.new || true
    mv -f ${CONFIG_FILE}.new $CONFIG_FILE 2>/dev/null
}

## add or replace option from file. Create the file if doesn't exist
_refresh_opt_in_file() {
    opt=$1
    value="$2"
    replace_line="$opt=$value"
    if $(grep -q "$opt=" $CONFIG_FILE); then
        sed "s/^$opt=.*/$replace_line/" $CONFIG_FILE 2>/dev/null >${CONFIG_FILE}.new
        mv -f ${CONFIG_FILE}.new $CONFIG_FILE 2>/dev/null
    else
        echo $replace_line >> $CONFIG_FILE
    fi
}

## Add/Update/Remove option from config depending if a value is defined or not.
## Handle unexisting config files and let options in place if additional comments were added.
## Options are in the form key=value.
update_opt_in_config() {
    opt=$1
    if ! value=$(snapctl get $opt) || [ -z "$value" ]; then
        _remove_opt_from_file $opt
    else
        _refresh_opt_in_file $opt "$value"
    fi
}

# Start here, update config we desire
update_opt_in_config port
update_opt_in_config title