#!/bin/bash
set -eo pipefail
cd $(dirname $0)/..

trap "rm -f a.cc" EXIT
declare -a headers
cd include
for i in qpdf/*.hh; do
    if [[ ! $i =~ .*auto_.* ]] && ! grep -q >/dev/null 2>&1 QPDFOBJECT_OLD_HH $i; then
        headers+=($i)
    fi
done
cd ..
# Make sure each header file can be included in isolation and that the
# result can be compiled with the intended version of the C++
# standard, which may be older than one we build with internally.
declare -a errors
for i in "${headers[@]}"; do
    rm -f a.cc
    cat > a.cc <<EOF
#include "$i"
int main() { return 0; }
EOF
    echo "Checking $i"
    if ! g++ -std=c++17 -pedantic-errors -c -Iinclude a.cc -o /dev/null; then
        errors+=("$i doesn't compile")
    fi
    # Fail if any C++20 headers are included. Modern g++/clang treat
    # these as empty if the compiler standard is too old.
    if grep -q >/dev/null 2>&1 -E "#\s*include\s*[<\"](concepts|coroutine|compare|ranges|format|source_location|version|span|bit|numbers|barrier|latch|semaphore|stop_token|syncstream)[>\"]" "include/$i"; then
        errors+=("$i includes a non-C++-17 standard header")
    fi
done
if [[ ${#errors[@]} -gt 0 ]]; then
    echo ""
    echo "Some header files had errors"
    for i in "${errors[@]}"; do
        echo "$i"
    done
    exit 2
fi