#include <stdlib.h>

#include "unity.h"
#include "celrs/serial.h"
#include "Mockserial_internal.h"

void setUp(void)    { Mockserial_internal_Init(); }
void tearDown(void) { Mockserial_internal_Verify(); Mockserial_internal_Destroy(); }

void test_open_valid_path(void) {
    cel_serial_platform_open_ExpectAndReturn("COM3", 400000, 1);
    cel_serial_port* port = cel_serial_open("COM3", 400000);
    TEST_ASSERT_NOT_NULL(port);

    cel_serial_platform_close_Expect(1);
    cel_serial_close(port);
}

void test_open_null_path(void) {
    TEST_ASSERT_NULL(cel_serial_open(NULL, 400000));
}

void test_open_platform_failure_returns_null(void) {
    cel_serial_platform_open_ExpectAndReturn("COM3", 400000, CEL_SERIAL_PLATFORM_INVALID_HANDLE);
    TEST_ASSERT_NULL(cel_serial_open("COM3", 400000));
}

void test_open_preserves_path(void) {
    cel_serial_platform_open_ExpectAndReturn("/dev/ttyUSB0", 400000, 1);
    cel_serial_port* port = cel_serial_open("/dev/ttyUSB0", 400000);
    TEST_ASSERT_NOT_NULL(port);
    /* path is stored internally; verify by roundtrip behavior */

    cel_serial_platform_close_Expect(1);
    cel_serial_close(port);
}

void test_close_null(void) {
    /* Should not crash */
    cel_serial_close(NULL);
}

void test_read_delegates_to_platform(void) {
    cel_serial_platform_open_ExpectAndReturn("COM3", 400000, 1);
    cel_serial_port* port = cel_serial_open("COM3", 400000);
    TEST_ASSERT_NOT_NULL(port);

    uint8_t buf[16];
    cel_serial_platform_read_ExpectAndReturn(1, buf, sizeof(buf), 4);
    size_t n = cel_serial_read(port, buf, sizeof(buf));
    TEST_ASSERT_EQUAL_UINT(4, n);

    cel_serial_platform_close_Expect(1);
    cel_serial_close(port);
}

void test_read_null_port_returns_zero(void) {
    uint8_t buf[16];
    TEST_ASSERT_EQUAL_UINT(0, cel_serial_read(NULL, buf, sizeof(buf)));
}

void test_write_delegates_to_platform(void) {
    cel_serial_platform_open_ExpectAndReturn("COM3", 400000, 1);
    cel_serial_port* port = cel_serial_open("COM3", 400000);
    TEST_ASSERT_NOT_NULL(port);

    uint8_t buf[4] = {0xC8, 0x10, 0x80, 0x03};
    cel_serial_platform_write_ExpectAndReturn(1, buf, sizeof(buf), sizeof(buf));
    size_t n = cel_serial_write(port, buf, sizeof(buf));
    TEST_ASSERT_EQUAL_UINT(sizeof(buf), n);

    cel_serial_platform_close_Expect(1);
    cel_serial_close(port);
}

void test_write_null_port_returns_zero(void) {
    uint8_t buf[4] = {0xC8, 0x10, 0x80, 0x03};
    TEST_ASSERT_EQUAL_UINT(0, cel_serial_write(NULL, buf, sizeof(buf)));
}

void test_flush_delegates_to_platform(void) {
    cel_serial_platform_open_ExpectAndReturn("COM3", 400000, 1);
    cel_serial_port* port = cel_serial_open("COM3", 400000);
    TEST_ASSERT_NOT_NULL(port);

    cel_serial_platform_flush_Expect(1);
    cel_serial_flush(port);

    cel_serial_platform_close_Expect(1);
    cel_serial_close(port);
}

void test_flush_null(void) {
    cel_serial_flush(NULL); /* should not crash */
}

void test_list_ports_null_out(void) {
    TEST_ASSERT_EQUAL_INT(-1, cel_serial_list_ports(NULL, 16));
}

void test_list_ports_passes_max_ports_through(void) {
    char** ports = NULL;
    cel_serial_platform_list_ports_ExpectAndReturn(&ports, 16, 2);
    int count = cel_serial_list_ports(&ports, 16);
    TEST_ASSERT_EQUAL_INT(2, count);
}

void test_list_ports_zero_max_uses_default(void) {
    char** ports = NULL;
    cel_serial_platform_list_ports_ExpectAndReturn(&ports, 64, 0);
    int count = cel_serial_list_ports(&ports, 0);
    TEST_ASSERT_EQUAL_INT(0, count);
}

void test_free_ports_null(void) {
    cel_serial_free_ports(NULL, 0); /* should not crash */
}

void test_free_ports_zero_count(void) {
    char** empty = (char**)calloc(1, sizeof(char*));
    cel_serial_free_ports(empty, 0); /* should not crash */
}

int main(void) {
    UNITY_BEGIN();
    RUN_TEST(test_open_valid_path);
    RUN_TEST(test_open_null_path);
    RUN_TEST(test_open_platform_failure_returns_null);
    RUN_TEST(test_open_preserves_path);
    RUN_TEST(test_close_null);
    RUN_TEST(test_read_delegates_to_platform);
    RUN_TEST(test_read_null_port_returns_zero);
    RUN_TEST(test_write_delegates_to_platform);
    RUN_TEST(test_write_null_port_returns_zero);
    RUN_TEST(test_flush_delegates_to_platform);
    RUN_TEST(test_flush_null);
    RUN_TEST(test_list_ports_null_out);
    RUN_TEST(test_list_ports_passes_max_ports_through);
    RUN_TEST(test_list_ports_zero_max_uses_default);
    RUN_TEST(test_free_ports_null);
    RUN_TEST(test_free_ports_zero_count);
    return UNITY_END();
}