// Records and JSON: serialize a record to a JSON string and parse it back.
// Demonstrates to_json/from_json round-tripping — the record's _type tag is
// part of its data, so is_a still recognizes it after a full round-trip.

cell JsonRecords {
    face {
        signal make() -> Map
        signal as_json() -> String
        signal reparse() -> Map
        signal tag_survives() -> Bool
        signal field_after_parse() -> String
    }

    on make() {
        return Profile { user: "ada", level: 7, prefs: list("dark", "compact") }
    }

    on as_json() {
        return to_json(make())
    }

    on reparse() {
        return from_json(as_json())
    }

    // Record literals carry _type; it serializes and parses back, so the
    // reparsed value is still recognized as a Profile.
    on tag_survives() {
        return is_a(reparse(), "Profile")
    }

    on field_after_parse() {
        return reparse().user
    }
}

cell test JsonRecordsTest {
    rules {
        assert make().level == 7
        assert is_a(make(), "Profile") == true
        assert contains(as_json(), "ada") == true
        assert tag_survives() == true
        assert field_after_parse() == "ada"
        assert reparse().prefs[0] == "dark"
    }
}