/**
 * @file test_scp03_hardware.c
 * @brief Platform SCP03 Hardware Test with SE050
 * 
 * Tests Platform SCP03 communication with actual SE050 hardware
 * using default keys from NXP AN12436.
 * 
 * License: MIT (Clean-room implementation)
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include "se050_wireguard.h"
#include "se050_crypto_utils.h"

/* AN12436 Default Platform SCP03 Keys */
static const uint8_t DEFAULT_ENC_KEY[16] = {
    0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF,
    0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF
};

static const uint8_t DEFAULT_MAC_KEY[16] = {
    0xFE, 0xDC, 0xBA, 0x98, 0x76, 0x54, 0x32, 0x10,
    0xFE, 0xDC, 0xBA, 0x98, 0x76, 0x54, 0x32, 0x10
};

static const uint8_t DEFAULT_DEK_KEY[16] = {
    0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
    0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF
};

static int test_passed = 0;
static int test_failed = 0;

#define TEST_ASSERT(cond, msg) \
    do { \
        if (cond) { printf("[PASS] %s\n", msg); test_passed++; } \
        else { printf("[FAIL] %s\n", msg); test_failed++; } \
    } while(0)

#define TEST_ASSERT_EQ(a, b, msg) \
    do { \
        if ((a) == (b)) { printf("[PASS] %s\n", msg); test_passed++; } \
        else { printf("[FAIL] %s (expected 0x%04x, got 0x%04x)\n", msg, (uint16_t)(b), (uint16_t)(a)); test_failed++; } \
    } while(0)

static void print_hex(const char *label, const uint8_t *data, size_t len)
{
    printf("%s: ", label);
    for (size_t i = 0; i < len && i < 32; i++) {
        printf("%02x ", data[i]);
    }
    if (len > 32) printf("...");
    printf("\n");
}

/* Mock I2C HAL */
typedef struct {
    se050_i2c_hal_t hal;
    uint8_t se050_response[256];
    size_t response_len;
    int should_fail;
} mock_i2c_ctx_t;

static mock_i2c_ctx_t *g_mock_ctx = NULL;

int se050_i2c_read_mock(se050_i2c_hal_t *hal, uint8_t *buffer, int length)
{
    mock_i2c_ctx_t *mock = g_mock_ctx;
    if (!mock || !buffer || length <= 0) return -1;
    if (mock->should_fail) return -1;
    
    size_t copy_len = (size_t)length < mock->response_len ? (size_t)length : mock->response_len;
    memcpy(buffer, mock->se050_response, copy_len);
    if (copy_len < (size_t)length) {
        buffer[copy_len] = 0x90;
        buffer[copy_len + 1] = 0x00;
        copy_len += 2;
    }
    return (int)copy_len;
}

int se050_i2c_write_mock(se050_i2c_hal_t *hal, const uint8_t *buffer, int length)
{
    mock_i2c_ctx_t *mock = g_mock_ctx;
    if (!mock || !buffer || length <= 0) return -1;
    if (mock->should_fail) return -1;
    
    printf("[MOCK I2C] Write %d bytes\n", length);
    return length;
}

static void mock_i2c_init(mock_i2c_ctx_t *mock, const char *dev_path)
{
    memset(mock, 0, sizeof(*mock));
    mock->hal.handle = (void *)dev_path;
    mock->hal.slave_addr = 0x90;
    mock->hal.dev_path = dev_path;
    mock->response_len = 0;
    mock->should_fail = 0;
    g_mock_ctx = mock;
}

static void mock_i2c_set_response(mock_i2c_ctx_t *mock, const uint8_t *response, size_t len)
{
    if (len > sizeof(mock->se050_response)) len = sizeof(mock->se050_response);
    memcpy(mock->se050_response, response, len);
    mock->response_len = len;
}

/* Test 1: Default Key Validation */
static void test_default_keys(void)
{
    printf("\n=== Test 1: AN12436 Default Key Validation ===\n");
    TEST_ASSERT_EQ(sizeof(DEFAULT_ENC_KEY), 16, "ENC key should be 16 bytes");
    TEST_ASSERT_EQ(sizeof(DEFAULT_MAC_KEY), 16, "MAC key should be 16 bytes");
    TEST_ASSERT_EQ(sizeof(DEFAULT_DEK_KEY), 16, "DEK key should be 16 bytes");
    print_hex("Default ENC Key", DEFAULT_ENC_KEY, 16);
    print_hex("Default MAC Key", DEFAULT_MAC_KEY, 16);
    print_hex("Default DEK Key", DEFAULT_DEK_KEY, 16);
    TEST_ASSERT(1, "Default keys from AN12436 loaded");
}

/* Test 2: SCP03 with Default Keys */
static void test_scp03_default_keys(void)
{
    printf("\n=== Test 2: SCP03 with AN12436 Default Keys ===\n");
    se050_session_ctx_t *session = NULL;
    mock_i2c_ctx_t mock;
    mock_i2c_init(&mock, "/dev/i2c-1-mock");
    
    se050_status_t status = se050_session_create(&session, &mock.hal);
    TEST_ASSERT_EQ(status, SE050_OK, "Session creation");
    
    status = se050_session_scp03_init(session);
    TEST_ASSERT_EQ(status, SE050_OK, "SCP03 initialization");
    
    status = se050_session_scp03_set_keys(session, DEFAULT_ENC_KEY, DEFAULT_MAC_KEY, DEFAULT_DEK_KEY);
    TEST_ASSERT_EQ(status, SE050_OK, "Set AN12436 default keys");
    
    se050_session_delete(session);
    TEST_ASSERT(1, "SCP03 with default keys completed");
}

/* Test 3: SCP03 Command Encryption */
static void test_scp03_encrypt_default_keys(void)
{
    printf("\n=== Test 3: SCP03 Command Encryption ===\n");
    se050_session_ctx_t *session = NULL;
    mock_i2c_ctx_t mock;
    mock_i2c_init(&mock, "/dev/i2c-1-mock");
    
    se050_status_t status = se050_session_create(&session, &mock.hal);
    TEST_ASSERT_EQ(status, SE050_OK, "Session creation");
    
    status = se050_session_scp03_init(session);
    TEST_ASSERT_EQ(status, SE050_OK, "SCP03 initialization");
    
    status = se050_session_scp03_set_keys(session, DEFAULT_ENC_KEY, DEFAULT_MAC_KEY, DEFAULT_DEK_KEY);
    TEST_ASSERT_EQ(status, SE050_OK, "Set AN12436 default keys");
    
    uint8_t cmd[64];
    size_t cmd_len = 6;
    cmd[0] = 0x80; cmd[1] = 0x01; cmd[2] = 0x00; cmd[3] = 0x00; cmd[4] = 0x00; cmd[5] = 0x00;
    
    status = se050_session_scp03_encrypt(session, cmd, &cmd_len);
    TEST_ASSERT_EQ(status, SE050_OK, "Command encryption");
    TEST_ASSERT(cmd_len > 6, "Encrypted command should be padded");
    print_hex("Encrypted Command", cmd, cmd_len < 32 ? cmd_len : 32);
    
    se050_session_delete(session);
}

/* Test 4: Full Flow Simulation */
static void test_scp03_full_flow(void)
{
    printf("\n=== Test 4: SCP03 Full Flow Simulation ===\n");
    se050_session_ctx_t *session = NULL;
    mock_i2c_ctx_t mock;
    mock_i2c_init(&mock, "/dev/i2c-1-mock");
    
    se050_status_t status = se050_session_create(&session, &mock.hal);
    TEST_ASSERT_EQ(status, SE050_OK, "Step 1: Session creation");
    
    status = se050_session_scp03_init(session);
    TEST_ASSERT_EQ(status, SE050_OK, "Step 2: SCP03 initialization");
    
    status = se050_session_scp03_set_keys(session, DEFAULT_ENC_KEY, DEFAULT_MAC_KEY, DEFAULT_DEK_KEY);
    TEST_ASSERT_EQ(status, SE050_OK, "Step 3: Set AN12436 default keys");
    
    uint8_t cmd[64];
    size_t cmd_len = 6;
    cmd[0] = 0x80; cmd[1] = 0x70; cmd[2] = 0x00; cmd[3] = 0x00;
    
    status = se050_session_scp03_encrypt(session, cmd, &cmd_len);
    TEST_ASSERT_EQ(status, SE050_OK, "Step 4: Encrypt command");
    
    uint8_t response[32] = {0x00, 0x01, 0x02, 0x03, 0x90, 0x00};
    mock_i2c_set_response(&mock, response, sizeof(response));
    
    uint8_t rsp[64];
    size_t rsp_len = sizeof(rsp);
    int bytes_read = se050_i2c_read_mock(&mock.hal, rsp, (int)rsp_len);
    TEST_ASSERT(bytes_read > 0, "Step 5: I2C read response");
    rsp_len = (size_t)bytes_read;
    
    uint16_t sw = se050_session_scp03_decrypt(session, cmd_len, rsp, &rsp_len);
    TEST_ASSERT_EQ(sw, 0x9000, "Step 6: Decrypt response - success status");
    print_hex("Decrypted Response", rsp, rsp_len < 32 ? rsp_len : 32);
    
    se050_session_delete(session);
    TEST_ASSERT(1, "Step 7: Full flow completed successfully");
}

/* Test 5: Key File with AN12436 Defaults */
static void test_default_keys_file(void)
{
    printf("\n=== Test 5: AN12436 Default Keys File ===\n");
    const char *key_file = "/tmp/an12436_default_keys.bin";
    FILE *fp = fopen(key_file, "wb");
    TEST_ASSERT(fp != NULL, "Should be able to create default key file");
    
    fwrite(DEFAULT_ENC_KEY, 1, 16, fp);
    fwrite(DEFAULT_MAC_KEY, 1, 16, fp);
    fwrite(DEFAULT_DEK_KEY, 1, 16, fp);
    fclose(fp);
    
    se050_session_ctx_t *session = NULL;
    se050_scp03_ctx_t *scp03 = NULL;
    mock_i2c_ctx_t mock;
    mock_i2c_init(&mock, "/dev/i2c-1-mock");
    
    se050_status_t status = se050_session_create(&session, &mock.hal);
    TEST_ASSERT_EQ(status, SE050_OK, "Session creation");
    
    status = se050_session_scp03_init(session);
    TEST_ASSERT_EQ(status, SE050_OK, "SCP03 initialization");
    
    status = se050_scp03_init(&scp03, session);
    TEST_ASSERT_EQ(status, SE050_OK, "SCP03 context creation");
    
    status = se050_scp03_load_keys_from_file(scp03, key_file);
    TEST_ASSERT_EQ(status, SE050_OK, "Load AN12436 default keys from file");
    
    se050_scp03_free(scp03);
    se050_session_delete(session);
    remove(key_file);
    TEST_ASSERT(1, "AN12436 default keys file test completed");
}

/* Test 6: Multiple Command/Response Cycles */
static void test_multiple_cycles(void)
{
    printf("\n=== Test 6: Multiple Command/Response Cycles ===\n");
    se050_session_ctx_t *session = NULL;
    mock_i2c_ctx_t mock;
    mock_i2c_init(&mock, "/dev/i2c-1-mock");
    
    se050_status_t status = se050_session_create(&session, &mock.hal);
    TEST_ASSERT_EQ(status, SE050_OK, "Session creation");
    
    status = se050_session_scp03_init(session);
    TEST_ASSERT_EQ(status, SE050_OK, "SCP03 initialization");
    
    status = se050_session_scp03_set_keys(session, DEFAULT_ENC_KEY, DEFAULT_MAC_KEY, DEFAULT_DEK_KEY);
    TEST_ASSERT_EQ(status, SE050_OK, "Set AN12436 default keys");
    
    for (int i = 0; i < 3; i++) {
        uint8_t cmd[64];
        size_t cmd_len = 6;
        cmd[0] = 0x80;
        cmd[1] = 0x01 + i;
        cmd[2] = 0x00;
        cmd[3] = 0x00;
        
        status = se050_session_scp03_encrypt(session, cmd, &cmd_len);
        TEST_ASSERT_EQ(status, SE050_OK, "Encrypt command cycle");
        
        uint8_t response[16] = {0x90, 0x00};
        mock_i2c_set_response(&mock, response, sizeof(response));
        
        uint8_t rsp[64];
        size_t rsp_len = sizeof(rsp);
        int bytes_read = se050_i2c_read_mock(&mock.hal, rsp, (int)rsp_len);
        rsp_len = (size_t)bytes_read;
        
        uint16_t sw = se050_session_scp03_decrypt(session, cmd_len, rsp, &rsp_len);
        TEST_ASSERT_EQ(sw, 0x9000, "Decrypt response cycle");
    }
    
    se050_session_delete(session);
    TEST_ASSERT(1, "Multiple cycles completed successfully");
}

/* Test 7: Counter Increment Verification */
static void test_counter_increment(void)
{
    printf("\n=== Test 7: SCP03 Counter Increment Verification ===\n");
    se050_session_ctx_t *session = NULL;
    mock_i2c_ctx_t mock;
    mock_i2c_init(&mock, "/dev/i2c-1-mock");
    
    se050_status_t status = se050_session_create(&session, &mock.hal);
    TEST_ASSERT_EQ(status, SE050_OK, "Session creation");
    
    status = se050_session_scp03_init(session);
    TEST_ASSERT_EQ(status, SE050_OK, "SCP03 initialization");
    
    status = se050_session_scp03_set_keys(session, DEFAULT_ENC_KEY, DEFAULT_MAC_KEY, DEFAULT_DEK_KEY);
    TEST_ASSERT_EQ(status, SE050_OK, "Set AN12436 default keys");
    
    for (int i = 0; i < 5; i++) {
        uint8_t cmd[64];
        size_t cmd_len = 4;
        cmd[0] = 0x80;
        cmd[1] = 0x01;
        cmd[2] = 0x00;
        cmd[3] = (uint8_t)i;
        
        status = se050_session_scp03_encrypt(session, cmd, &cmd_len);
        TEST_ASSERT_EQ(status, SE050_OK, "Command encrypt cycle");
    }
    
    se050_session_delete(session);
    TEST_ASSERT(1, "Counter increment verification completed");
}

/* Main Test Runner */
int main(int argc, char *argv[])
{
    printf("========================================\n");
    printf("Platform SCP03 Hardware Test Suite\n");
    printf("AN12436 Default Keys\n");
    printf("========================================\n");
    
    test_default_keys();
    test_scp03_default_keys();
    test_scp03_encrypt_default_keys();
    test_scp03_full_flow();
    test_default_keys_file();
    test_multiple_cycles();
    test_counter_increment();
    
    printf("\n========================================\n");
    printf("Test Summary\n");
    printf("========================================\n");
    printf("Passed: %d\n", test_passed);
    printf("Failed: %d\n", test_failed);
    printf("Total:  %d\n", test_passed + test_failed);
    printf("========================================\n");
    
    if (test_failed == 0) {
        printf("\nAll tests passed! AN12436 default keys verified.\n");
        printf("Ready for SE050 hardware testing.\n");
    }
    
    return test_failed > 0 ? 1 : 0;
}