// Streaming SHA-256 (FIPS 180-4) from `modules/std/hash.sx`.
//
// Known-answer vectors (empty, "abc", the 112-byte NIST multi-block
// vector) plus the streaming invariant: feeding the same bytes in
// several `update` chunks yields the same digest as the one-shot call.

#import "modules/std.sx";
#import "modules/std/hash.sx";

check :: (label: string, got: string, want: string) {
    if got == want {
        print("{}: ok\n", label);
    } else {
        print("{}: FAIL got {} want {}\n", label, got, want);
    }
}

main :: () {
    check("empty", sha256_hex(""),
        "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855");
    check("abc", sha256_hex("abc"),
        "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad");

    // 112-byte input — spans more than one 64-byte block.
    multi := "abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmnhijklmnoijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu";
    check("multi", sha256_hex(multi),
        "cf5b16a778af8380036ce59e7b0492370b249b11e8f07a51afac45037afee9d1");

    // Streaming must equal one-shot regardless of chunk boundaries.
    h := init();
    h.update("abcdefghbcdefghicdefghijdefghijke");   // 33 bytes
    h.update("fghijklfghijklmghijklmnhijklmno");      // crosses block edge
    h.update("ijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu");
    streamed := h.final();
    check("stream-eq-oneshot",
        if streamed == sha256_hex(multi) then "yes" else "no", "yes");
}