package ai.nomyo;

import org.junit.jupiter.api.*;

import java.util.Map;

import static org.junit.jupiter.api.Assertions.*;

@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
class SecureMemoryTest {

    @BeforeEach
    void resetSecureMemoryState() {
        SecureMemory.setSecureMemoryEnabled(true);
    }

    @Test
    @DisplayName("getMemoryProtectionInfo should return enabled=true by default")
    void getMemoryProtectionInfo_default_shouldBeEnabled() {
        Map<String, Object> info = SecureMemory.getMemoryProtectionInfo();

        assertEquals(true, info.get("enabled"), "Memory protection should be enabled by default");
    }

    @Test
    @DisplayName("getMemoryProtectionInfo should report has_secure_zeroing=true")
    void getMemoryProtectionInfo_shouldReportZeroing() {
        Map<String, Object> info = SecureMemory.getMemoryProtectionInfo();

        assertEquals(true, info.get("has_secure_zeroing"), "Should report secure zeroing available");
    }

    @Test
    @DisplayName("getMemoryProtectionInfo should report has_memory_locking=false")
    void getMemoryProtectionInfo_shouldReportNoLocking() {
        Map<String, Object> info = SecureMemory.getMemoryProtectionInfo();

        assertEquals(false, info.get("has_memory_locking"), "Should report memory locking unavailable");
    }

    @Test
    @DisplayName("getMemoryProtectionInfo should report protection_level=zeroing_only")
    void getMemoryProtectionInfo_protectionLevel_shouldBeZeroingOnly() {
        Map<String, Object> info = SecureMemory.getMemoryProtectionInfo();

        assertEquals("zeroing_only", info.get("protection_level"),
                "Protection level should be zeroing_only (no memory locking)");
    }

    @Test
    @DisplayName("getMemoryProtectionInfo should return page_size from Constants")
    void getMemoryProtectionInfo_pageSize_shouldMatchConstants() {
        Map<String, Object> info = SecureMemory.getMemoryProtectionInfo();

        assertEquals(Constants.PAGE_SIZE, info.get("page_size"),
                "Page size should match Constants.PAGE_SIZE");
    }

    @Test
    @DisplayName("getMemoryProtectionInfo should report supports_full_protection=false without locking")
    void getMemoryProtectionInfo_fullProtection_shouldBeFalse() {
        Map<String, Object> info = SecureMemory.getMemoryProtectionInfo();

        assertEquals(false, info.get("supports_full_protection"),
                "Full protection should be false without memory locking");
    }

    @Test
    @DisplayName("getMemoryProtectionInfo should report supports_full_protection=false when disabled")
    void getMemoryProtectionInfo_disabled_shouldNotSupportFull() {
        SecureMemory.setSecureMemoryEnabled(false);
        try {
            Map<String, Object> info = SecureMemory.getMemoryProtectionInfo();
            assertEquals(false, info.get("supports_full_protection"),
                    "Full protection should be false when disabled");
            assertEquals(false, info.get("enabled"), "Enabled should be false");
        } finally {
            SecureMemory.setSecureMemoryEnabled(true);
        }
    }

    @Test
    @DisplayName("secureByteArray should create a SecureBuffer with data")
    void secureByteArray_shouldCreateBuffer() {
        byte[] data = new byte[]{1, 2, 3, 4, 5};

        try (SecureMemory.SecureBuffer buffer = SecureMemory.secureByteArray(data)) {
            assertNotNull(buffer.getData(), "Data segment should not be null");
            assertEquals(5, buffer.getSize(), "Size should match input");
            assertNotEquals(0, buffer.getAddress(), "Address should not be zero");
        }
    }

    @Test
    @DisplayName("secureByteArray should handle null data gracefully")
    void secureByteArray_nullData_shouldHandleGracefully() {
        try (SecureMemory.SecureBuffer buffer = SecureMemory.secureByteArray(null)) {
            assertNotNull(buffer, "Buffer should not be null even with null data");
            assertEquals(0, buffer.getSize(), "Size should be 0 for null data");
        }
    }

    @Test
    @DisplayName("SecureBuffer zero should clear all bytes")
    void secureBuffer_zero_shouldClearBytes() {
        byte[] data = new byte[]{(byte)0xFF, (byte)0xFF, (byte)0xFF, (byte)0xFF};
        SecureMemory.SecureBuffer buffer = SecureMemory.secureByteArray(data);

        buffer.zero();

        assertDoesNotThrow(() -> buffer.zero(), "Zeroing should not throw");
    }

    @Test
    @DisplayName("SecureBuffer close should zero and unlock")
    void secureBuffer_close_shouldZeroAndUnlock() {
        byte[] data = new byte[]{1, 2, 3};

        assertDoesNotThrow(() -> {
            try (SecureMemory.SecureBuffer buffer = SecureMemory.secureByteArray(data)) {
                assertNotNull(buffer.getData());
            }
        }, "Close via try-with-resources should not throw");
    }

    @Test
    @DisplayName("SecureBuffer close should be idempotent")
    void secureBuffer_close_idempotent() {
        byte[] data = new byte[]{1, 2, 3};
        SecureMemory.SecureBuffer buffer = SecureMemory.secureByteArray(data);

        assertDoesNotThrow(() -> buffer.close(), "First close should not throw");
        assertDoesNotThrow(() -> buffer.close(), "Second close should not throw");
    }

    @Test
    @DisplayName("SecureBuffer lock should return false (not supported)")
    void secureBuffer_lock_shouldReturnFalse() {
        byte[] data = new byte[]{1, 2, 3};
        SecureMemory.SecureBuffer buffer = SecureMemory.secureByteArray(data, true);

        assertFalse(buffer.lock(), "Lock should return false (not supported)");
    }

    @Test
    @DisplayName("SecureBuffer unlock should return false")
    void secureBuffer_unlock_shouldReturnFalse() {
        byte[] data = new byte[]{1, 2, 3};
        SecureMemory.SecureBuffer buffer = SecureMemory.secureByteArray(data, true);

        assertFalse(buffer.unlock(), "Unlock should return false");
    }

    @Test
    @DisplayName("HAS_MEMORY_LOCKING should be false")
    void hasMemoryLocking_shouldBeFalse() {
        assertFalse(SecureMemory.isHAS_MEMORY_LOCKING(), "HAS_MEMORY_LOCKING should be false");
    }

    @Test
    @DisplayName("HAS_SECURE_ZEROING should be true")
    void hasSecureZeroing_shouldBeTrue() {
        assertTrue(SecureMemory.isHAS_SECURE_ZEROING(), "HAS_SECURE_ZEROING should be true");
    }
}