#!/usr/bin/env bash

phase=phase0

phase0() {
        phase=phase0
        local line="$1"
        case "$line" in
                '#include'*|'typedef '*';')
                        phase1 "$line"
                        ;;
                *)
                        ;;
        esac
}

phase1() {
        phase=phase1
        local line="$1"
        case "$line" in
                '')
                        ;;
                '#include'*)
                        ;;
                'typedef '*';')
                        ;;
                *)
                        phase2 "$line"
                        ;;
        esac
}

phase2() {
        phase=phase2
        local line="$1"
        printf '%s\n' "$line"
        cat
}

main() {
        current_file="$1"
        set -o pipefail
        {
                IFS=''
                while read -r line; do
                        "$phase" "$line"
                        IFS=''
                done
        } < "$current_file" | grep '^#include' | ifne printf '%s\n' "$current_file"
}

main "$@"