#include <unity.h>
#include <ArduinoJson.h>

struct TestConfig {
    char wifi_ssid[33];
    char wifi_password[65];
    char mqtt_broker[65];
    uint16_t mqtt_port;
    uint8_t modbus_address;
    uint32_t modbus_baud;
    uint16_t poll_interval_sec;
    uint8_t transport_priority;
};

static bool validateConfig(TestConfig& cfg) {
    if (strlen(cfg.wifi_ssid) == 0) return false;
    if (cfg.mqtt_port == 0 || cfg.mqtt_port > 65535) return false;
    if (cfg.modbus_address == 0 || cfg.modbus_address > 247) return false;
    if (cfg.modbus_baud != 9600 && cfg.modbus_baud != 19200 &&
        cfg.modbus_baud != 38400 && cfg.modbus_baud != 57600 &&
        cfg.modbus_baud != 115200) return false;
    if (cfg.poll_interval_sec < 1 || cfg.poll_interval_sec > 3600) return false;
    if (cfg.transport_priority > 3) return false;
    return true;
}

void test_valid_config() {
    TestConfig cfg;
    strncpy(cfg.wifi_ssid, "TestNetwork", sizeof(cfg.wifi_ssid));
    strncpy(cfg.wifi_password, "password123", sizeof(cfg.wifi_password));
    strncpy(cfg.mqtt_broker, "broker.example.com", sizeof(cfg.mqtt_broker));
    cfg.mqtt_port = 1883;
    cfg.modbus_address = 1;
    cfg.modbus_baud = 9600;
    cfg.poll_interval_sec = 5;
    cfg.transport_priority = 0;

    TEST_ASSERT_TRUE(validateConfig(cfg));
}

void test_empty_ssid_invalid() {
    TestConfig cfg = {};
    cfg.mqtt_port = 1883;
    cfg.modbus_address = 1;
    cfg.modbus_baud = 9600;
    cfg.poll_interval_sec = 5;

    TEST_ASSERT_FALSE(validateConfig(cfg));
}

void test_invalid_modbus_address() {
    TestConfig cfg;
    strncpy(cfg.wifi_ssid, "TestNetwork", sizeof(cfg.wifi_ssid));
    cfg.mqtt_port = 1883;
    cfg.modbus_address = 0;
    cfg.modbus_baud = 9600;
    cfg.poll_interval_sec = 5;
    cfg.transport_priority = 0;

    TEST_ASSERT_FALSE(validateConfig(cfg));

    cfg.modbus_address = 248;
    TEST_ASSERT_FALSE(validateConfig(cfg));
}

void test_invalid_baud_rate() {
    TestConfig cfg;
    strncpy(cfg.wifi_ssid, "TestNetwork", sizeof(cfg.wifi_ssid));
    cfg.mqtt_port = 1883;
    cfg.modbus_address = 1;
    cfg.modbus_baud = 12345;
    cfg.poll_interval_sec = 5;
    cfg.transport_priority = 0;

    TEST_ASSERT_FALSE(validateConfig(cfg));
}

void test_poll_interval_bounds() {
    TestConfig cfg;
    strncpy(cfg.wifi_ssid, "TestNetwork", sizeof(cfg.wifi_ssid));
    cfg.mqtt_port = 1883;
    cfg.modbus_address = 1;
    cfg.modbus_baud = 9600;
    cfg.transport_priority = 0;

    cfg.poll_interval_sec = 0;
    TEST_ASSERT_FALSE(validateConfig(cfg));

    cfg.poll_interval_sec = 3601;
    TEST_ASSERT_FALSE(validateConfig(cfg));

    cfg.poll_interval_sec = 1;
    TEST_ASSERT_TRUE(validateConfig(cfg));

    cfg.poll_interval_sec = 3600;
    TEST_ASSERT_TRUE(validateConfig(cfg));
}

void test_config_from_json() {
    const char* json = R"({"wifi":{"ssid":"TestNet","password":"pass123"},"mqtt":{"broker":"mqtt.test","port":8883},"modbus":{"address":5,"baud":19200,"poll_interval":10}})";

    JsonDocument doc;
    DeserializationError err = deserializeJson(doc, json);
    TEST_ASSERT_EQUAL(DeserializationError::Ok, err);

    TestConfig cfg = {};
    strncpy(cfg.wifi_ssid, doc["wifi"]["ssid"] | "", sizeof(cfg.wifi_ssid));
    strncpy(cfg.wifi_password, doc["wifi"]["password"] | "", sizeof(cfg.wifi_password));
    strncpy(cfg.mqtt_broker, doc["mqtt"]["broker"] | "", sizeof(cfg.mqtt_broker));
    cfg.mqtt_port = doc["mqtt"]["port"] | 1883;
    cfg.modbus_address = doc["modbus"]["address"] | 1;
    cfg.modbus_baud = doc["modbus"]["baud"] | 9600;
    cfg.poll_interval_sec = doc["modbus"]["poll_interval"] | 5;
    cfg.transport_priority = 0;

    TEST_ASSERT_EQUAL_STRING("TestNet", cfg.wifi_ssid);
    TEST_ASSERT_EQUAL(8883, cfg.mqtt_port);
    TEST_ASSERT_EQUAL(5, cfg.modbus_address);
    TEST_ASSERT_EQUAL(19200, cfg.modbus_baud);
    TEST_ASSERT_EQUAL(10, cfg.poll_interval_sec);
    TEST_ASSERT_TRUE(validateConfig(cfg));
}

void test_config_to_json() {
    TestConfig cfg;
    strncpy(cfg.wifi_ssid, "MyNetwork", sizeof(cfg.wifi_ssid));
    strncpy(cfg.mqtt_broker, "broker.local", sizeof(cfg.mqtt_broker));
    cfg.mqtt_port = 1883;
    cfg.modbus_address = 1;
    cfg.modbus_baud = 9600;
    cfg.poll_interval_sec = 5;

    JsonDocument doc;
    JsonObject root = doc.to<JsonObject>();
    root["wifi"]["ssid"] = cfg.wifi_ssid;
    root["mqtt"]["broker"] = cfg.mqtt_broker;
    root["mqtt"]["port"] = cfg.mqtt_port;
    root["modbus"]["address"] = cfg.modbus_address;
    root["modbus"]["baud"] = cfg.modbus_baud;
    root["modbus"]["poll_interval"] = cfg.poll_interval_sec;

    String output;
    serializeJson(doc, output);

    TEST_ASSERT_TRUE(output.indexOf("MyNetwork") >= 0);
    TEST_ASSERT_TRUE(output.indexOf("1883") >= 0);
}

void setup() {
    delay(2000);
    UNITY_BEGIN();
    RUN_TEST(test_valid_config);
    RUN_TEST(test_empty_ssid_invalid);
    RUN_TEST(test_invalid_modbus_address);
    RUN_TEST(test_invalid_baud_rate);
    RUN_TEST(test_poll_interval_bounds);
    RUN_TEST(test_config_from_json);
    RUN_TEST(test_config_to_json);
    UNITY_END();
}

void loop() {}