/* test/storage/test_page.c
 *
 * TDD-Zyklus: test_page_create
 * RED   -> diese Datei schreiben, noch kein page.c -> Linker-Fehler
 * GREEN -> page_create() + page_free() in page.c implementieren
 */
#include "pauldb/storage.h"

#include <assert.h>
#include <stdio.h>
#include <string.h>

static void
test_create_returns_non_null(void)
{
    Page* p = page_create(42);
    assert(p != NULL);
    page_free(p);
    printf("  OK: page_create(42) returns non-NULL\n");
}

static void
test_insert_returns_slot_id(void)
{
    Page* p = page_create(4);
    int slot_id = page_insert(p, "Hallo", 5);
    assert(slot_id == 0);
    page_free(p);
    printf("  OK: Insert\n");
}

static void
test_insert_and_get(void)
{
    Page* p = page_create(1);

    int slot = page_insert(p, "ABAP", 4);
    assert(slot == 0);

    size_t len = 0;
    void* result = page_get(p, 0, &len);
    assert(result != NULL);
    assert(len == 4);
    assert(memcmp(result, "ABAP", 4) == 0);

    page_free(p);
    printf("  OK: insert + get roundtrip\n");
}

static void
test_multiple_inserts(void)
{
    Page* p = page_create(2);

    assert(page_insert(p, "ABAP", 4) == 0);
    assert(page_insert(p, "HANA", 4) == 1);
    assert(page_insert(p, "CDS", 3) == 2);

    size_t len = 0;
    assert(memcmp(page_get(p, 0, &len), "ABAP", 4) == 0);
    assert(memcmp(page_get(p, 1, &len), "HANA", 4) == 0);
    assert(memcmp(page_get(p, 2, &len), "CDS", 3) == 0);

    page_free(p);
    printf("  OK: multiple inserts\n");
}

static void
test_invalid_slot_returns_null(void)
{
    Page* p = page_create(3);
    assert(page_get(p, 99, NULL) == NULL);
    page_free(p);
    printf("  OK: invalid slot returns NULL\n");
}

int
main(void)
{
    printf("=== test_page ===\n");
    test_create_returns_non_null();
    test_insert_returns_slot_id();
    test_insert_and_get();
    test_multiple_inserts();
    test_invalid_slot_returns_null();
    printf("All tests passed.\n");
    return 0;
}