# shellcheck shell=dash
# vim: ft=sh

# substitute replaces all occurances of one string with another in the provided
# file, writing to the specified output file.
substitute() {
    local input="$1"
    local output="$2"

    shift 2

    # TODO: real parsing
    local search="$1"
    local replace="$2"

        #-v RS="$(printf "\0")" \
    awk \
        -v srch="$search" \
        -v repl="$replace" \
        -v RS="" \
        -v ORS="" \
        '{ gsub(srch, repl, $0); print $0 }' \
        < "$input" > "$output"
}

# substituteInPlace works like substitute but operates in-place on the provided
# file
substituteInPlace() {
    local fpath="$1"
    shift

    local tmpfile
    tmpfile="$(mktemp)"
    
    if ! substitute "$fpath" "$tmpfile" "$@"; then
        rm "$tmpfile"
        return $?
    fi

    # Overwrite now that we've succeeded
    mv "$tmpfile" "$fpath"
}