use bufio;
use io;
use memio;

// Reads an IEND chunk from a [[reader]]. This function simply performs a sanity
// check and verifies the chunk checksum.
export fn iend_read(src: *reader) (void | error) = {
	assert(chunk_type(src) == IEND,
		"Attempted to call iend_read on non-IEND chunk");
	io::copy(io::empty, src)?;
};

@test fn iend_reader() void = {
	const src = memio::fixed(simple_png);
	const read = newreader(&src) as reader;
	assert(nextchunk(&read) as u32 == IHDR);
	io::copy(io::empty, &read)!;

	for (true) {
		if (nextchunk(&read) as u32 == IEND) {
			break;
		};
		io::copy(io::empty, &read)!;
	};

	iend_read(&read)!;
};