// Host tests of dispatch: which device and which capability a directive reaches, what the handler is given, what
// a device holds, and what the device answers itself (src/AlexaDevice.cpp). The transport of the devices is a
// fake that keeps what would have been published.
//   pio test -e native
#include <unity.h>
#include <ArduinoJson.h>
#include <stdio.h>
#include <string.h>
#include <string>
#include <vector>
#include "AlexaDevice.h"
#include "AlexaLog.h"

class FakeTransport : public AlexaTransport
{
public:
    struct Message
    {
        std::string topic;
        std::string json;
    };
    std::vector<Message> sent;

    AlexaSendResult publish(const char *topic, JsonDocument &doc) override
    {
        Message message;
        message.topic = topic;
        serializeJson(doc, message.json);
        sent.push_back(message);
        return AlexaSendResult::OK;
    }

    void timestamp(char *buffer, size_t size) override { snprintf(buffer, size, "2026-09-28T13:05:09Z"); }
};

class CapturedLog : public Print
{
public:
    std::string text;

    size_t write(const uint8_t *buffer, size_t size) override
    {
        text.append(reinterpret_cast<const char *>(buffer), size);
        return size;
    }
};

static void assertLogged(const CapturedLog &log, const char *expected)
{
    TEST_ASSERT_NOT_NULL_MESSAGE(strstr(log.text.c_str(), expected), log.text.c_str());
}

// What the handler of the tests was given, copied: the texts of a directive end with the handler
struct Seen
{
    int calls;
    AlexaDevice *device;
    AlexaCapability *capability;
    AlexaInterfaceType type;
    std::string ns;
    std::string name;
    std::string instance;
    std::string correlationToken;
    int rangeValue;
    bool reportState;
};

static Seen seen;
static bool handlerAnswers;

static void onDirective(AlexaDirective &directive)
{
    seen.calls++;
    seen.device = directive.device;
    seen.capability = directive.capability;
    seen.type = directive.type;
    seen.ns = directive.ns;
    seen.name = directive.name;
    seen.instance = directive.instance;
    seen.correlationToken = directive.correlationToken;
    seen.rangeValue = directive.payload["rangeValue"] | -1;
    seen.reportState = directive.isReportState();
    if (!handlerAnswers)
    {
        return;
    }
    if (directive.isReportState())
    {
        directive.stateReport().AddPowerControllerProp(PowerController::OFF).send();
    }
    else
    {
        directive.response().AddPowerControllerProp(directive.is("TurnOn") ? PowerController::ON : PowerController::OFF).send();
    }
}

static int eventCalls;
static int reportStateCalls;
static AlexaInterfaceType eventType;

static void onEvent(const JsonDocument &, const AlexaInterfaceType &type)
{
    eventCalls++;
    eventType = type;
}

static void onReportState(const JsonDocument &, const AlexaInterfaceType &)
{
    reportStateCalls++;
}

// The directive as Alex2MQTT publishes it on <root>/<endpointId>/alexaDirective
static void directiveFor(JsonDocument &message, const char *endpointId, const char *ns, const char *name,
                         const char *instance = nullptr)
{
    message.clear();
    message["header"]["namespace"] = ns;
    message["header"]["name"] = name;
    message["header"]["payloadVersion"] = "3";
    message["header"]["messageId"] = "5f8a426e-01e4-4cc9-8b79-65f8bd0fd8a4";
    message["header"]["correlationToken"] = "token-of-the-directive";
    if (instance != nullptr)
    {
        message["header"]["instance"] = instance;
    }
    message["endpoint"]["endpointId"] = endpointId;
    message["payload"].to<JsonObject>();
}

static void assertErrorResponse(const FakeTransport::Message &message, const char *topic)
{
    TEST_ASSERT_EQUAL_STRING(topic, message.topic.c_str());
    JsonDocument answer;
    TEST_ASSERT_TRUE(deserializeJson(answer, message.json) == DeserializationError::Ok);
    TEST_ASSERT_EQUAL_STRING("Alexa", answer["event"]["header"]["namespace"] | "");
    TEST_ASSERT_EQUAL_STRING("ErrorResponse", answer["event"]["header"]["name"] | "");
    TEST_ASSERT_EQUAL_STRING("token-of-the-directive", answer["event"]["header"]["correlationToken"] | "");
    TEST_ASSERT_EQUAL_STRING("INVALID_DIRECTIVE", answer["event"]["payload"]["type"] | "");
    TEST_ASSERT_TRUE(strlen(answer["event"]["payload"]["message"] | "") > 0);
    TEST_ASSERT_TRUE(answer["context"].isNull()); // alexa-errorresponse.html: an ErrorResponse has no context
}

void setUp(void)
{
    AlexaLog::setOutput(nullptr);
    seen = Seen();
    handlerAnswers = true;
    eventCalls = 0;
    reportStateCalls = 0;
    eventType = AlexaInterfaceType::UNKNOWN;
}

void tearDown(void) {}

void test_devices_are_found_by_their_endpoint_id_in_the_order_they_were_created(void)
{
    AlexaDeviceList devices;
    TEST_ASSERT_NULL(devices.first());
    AlexaDevice *lamp = devices.add("Lamp", "root", "ESP-01", nullptr);
    AlexaDevice *fan = devices.add("Fan", "root", "ESP-02", nullptr);
    AlexaDevice *blind = devices.add("Blind", "root", "ESP-03", nullptr);

    TEST_ASSERT_EQUAL(3, devices.size());
    TEST_ASSERT_EQUAL_PTR(lamp, devices.first());
    TEST_ASSERT_EQUAL_PTR(fan, lamp->nextDevice());
    TEST_ASSERT_EQUAL_PTR(blind, fan->nextDevice());
    TEST_ASSERT_NULL(blind->nextDevice());
    TEST_ASSERT_EQUAL_PTR(fan, devices.find("ESP-02", 6));
    // The id is a part of a topic: "ESP-02/alexaDirective"
    TEST_ASSERT_EQUAL_PTR(fan, devices.find("ESP-02/alexaDirective", 6));
    // An endpoint of another board
    TEST_ASSERT_NULL(devices.find("ESP-04", 6));
    TEST_ASSERT_NULL(devices.find("ESP-0", 5));
}

void test_one_handler_serves_two_devices_and_is_told_which(void)
{
    FakeTransport transport;
    AlexaDeviceList devices;
    AlexaDevice *lamp = devices.add("Lamp", "root", "ESP-01", &transport);
    AlexaDevice *fan = devices.add("Fan", "root", "ESP-02", &transport);
    lamp->addCapability(AlexaInterfaces::PowerController);
    AlexaCapability *fanPower = fan->addCapability(AlexaInterfaces::PowerController);
    lamp->onDirective(onDirective);
    fan->onDirective(onDirective);

    JsonDocument message;
    directiveFor(message, "ESP-02", "Alexa.PowerController", "TurnOn");
    devices.find("ESP-02", 6)->handleDirective(message);

    TEST_ASSERT_EQUAL(1, seen.calls);
    TEST_ASSERT_EQUAL_PTR(fan, seen.device);
    TEST_ASSERT_EQUAL_PTR(fanPower, seen.capability);
    TEST_ASSERT_TRUE(AlexaInterfaceType::POWER_CONTROLLER == seen.type);
    TEST_ASSERT_EQUAL_STRING("Alexa.PowerController", seen.ns.c_str());
    TEST_ASSERT_EQUAL_STRING("TurnOn", seen.name.c_str());
    TEST_ASSERT_EQUAL_STRING("", seen.instance.c_str());
    TEST_ASSERT_EQUAL_STRING("token-of-the-directive", seen.correlationToken.c_str());
    TEST_ASSERT_FALSE(seen.reportState);

    TEST_ASSERT_EQUAL(1, transport.sent.size());
    TEST_ASSERT_EQUAL_STRING("root/ESP-02/alexaResponce", transport.sent[0].topic.c_str());
    JsonDocument answer;
    TEST_ASSERT_TRUE(deserializeJson(answer, transport.sent[0].json) == DeserializationError::Ok);
    TEST_ASSERT_EQUAL_STRING("Response", answer["event"]["header"]["name"] | "");
    TEST_ASSERT_EQUAL_STRING("token-of-the-directive", answer["event"]["header"]["correlationToken"] | "");
    TEST_ASSERT_EQUAL_STRING("ESP-02", answer["event"]["endpoint"]["endpointId"] | "");
    TEST_ASSERT_EQUAL_STRING("ON", answer["context"]["properties"][0]["value"] | "");
    TEST_ASSERT_EQUAL_STRING("2026-09-28T13:05:09Z", answer["context"]["properties"][0]["timeOfSample"] | "");
}

void test_directive_with_an_instance_reaches_the_capability_with_that_instance(void)
{
    FakeTransport transport;
    AlexaDevice blind("Blind", "root", "ESP-01", &transport);
    AlexaCapability *lift = blind.addCapability(AlexaInterfaces::RangeController, "Blind.Lift");
    AlexaCapability *tilt = blind.addCapability(AlexaInterfaces::RangeController, "Blind.Tilt");
    blind.onDirective(onDirective);

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa.RangeController", "SetRangeValue", "Blind.Tilt");
    message["payload"]["rangeValue"] = 40;
    blind.handleDirective(message);

    TEST_ASSERT_EQUAL_PTR(tilt, seen.capability);
    TEST_ASSERT_TRUE(AlexaInterfaceType::RANGE_CONTROLLER == seen.type);
    TEST_ASSERT_EQUAL_STRING("Blind.Tilt", seen.instance.c_str());
    TEST_ASSERT_EQUAL(40, seen.rangeValue);

    TEST_ASSERT_EQUAL_PTR(lift, blind.findCapability("Alexa.RangeController", "Blind.Lift"));
    TEST_ASSERT_NULL(blind.findCapability("Alexa.RangeController", "Blind.Slat"));
    TEST_ASSERT_NULL(blind.findCapability("Alexa.RangeController", ""));
    TEST_ASSERT_NULL(blind.findCapability("Alexa.ModeController", "Blind.Lift"));
}

void test_report_state_is_handed_over_without_a_capability_and_answered_with_a_state_report(void)
{
    FakeTransport transport;
    AlexaDevice lamp("Lamp", "root", "ESP-01", &transport);
    lamp.addCapability(AlexaInterfaces::PowerController);
    lamp.onDirective(onDirective);

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa", "ReportState");
    lamp.handleDirective(message);

    TEST_ASSERT_TRUE(seen.reportState);
    TEST_ASSERT_NULL(seen.capability);
    TEST_ASSERT_EQUAL(1, transport.sent.size());
    JsonDocument answer;
    TEST_ASSERT_TRUE(deserializeJson(answer, transport.sent[0].json) == DeserializationError::Ok);
    TEST_ASSERT_EQUAL_STRING("StateReport", answer["event"]["header"]["name"] | "");
    TEST_ASSERT_EQUAL_STRING("OFF", answer["context"]["properties"][0]["value"] | "");
}

void test_one_capability_more_than_a_device_holds_is_refused_with_an_error(void)
{
    CapturedLog log;
    AlexaDevice device("Panel", "root", "ESP-01");
    AlexaCapability *first = nullptr;
    for (int i = 0; i < ALEX2ESP_MAX_CAPABILITIES; i++)
    {
        char instance[16];
        snprintf(instance, sizeof(instance), "Panel.%d", i);
        AlexaCapability *added = device.addCapability(AlexaInterfaces::ToggleController, instance);
        TEST_ASSERT_NOT_NULL(added);
        added->addFriendlyName("Switch", "en-US");
        if (i == 0)
        {
            first = added;
        }
    }
    std::string full;
    serializeJson(device.getDeviceJSON(), full);

    AlexaLog::setOutput(&log);
    TEST_ASSERT_NULL(device.addCapability(AlexaInterfaces::PowerController));
    TEST_ASSERT_NULL(device.addCapability(AlexaInterfaceType::BRIGHTNESS_CONTROLLER));

    char expected[160];
    snprintf(expected, sizeof(expected),
             "error: ESP-01: capability Alexa.PowerController not added: the device has %d already "
             "(ALEX2ESP_MAX_CAPABILITIES)",
             ALEX2ESP_MAX_CAPABILITIES);
    assertLogged(log, expected);
    assertLogged(log, "error: ESP-01: capability Alexa.BrightnessController not added");

    // What it has is still found and announced
    TEST_ASSERT_EQUAL_PTR(first, device.addCapability(AlexaInterfaces::ToggleController, "Panel.0"));
    TEST_ASSERT_NULL(device.findCapability("Alexa.PowerController", ""));
    std::string announced;
    serializeJson(device.getDeviceJSON(), announced);
    TEST_ASSERT_EQUAL_STRING(full.c_str(), announced.c_str());
}

void test_directive_for_an_interface_the_device_lacks_is_answered_with_invalid_directive(void)
{
    CapturedLog log;
    AlexaLog::setOutput(&log);
    FakeTransport transport;
    AlexaDevice lamp("Lamp", "root", "ESP-01", &transport);
    lamp.addCapability(AlexaInterfaces::PowerController);
    lamp.onDirective(onDirective);
    handlerAnswers = false; // as a handler that knows its own interfaces and leaves the others alone

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa.LockController", "Lock");
    lamp.handleDirective(message);

    // The handler is asked first: it sees that the device has no such capability
    TEST_ASSERT_EQUAL(1, seen.calls);
    TEST_ASSERT_NULL(seen.capability);
    TEST_ASSERT_TRUE(AlexaInterfaceType::UNKNOWN == seen.type);
    TEST_ASSERT_EQUAL(1, transport.sent.size());
    assertErrorResponse(transport.sent[0], "root/ESP-01/alexaResponce");
    assertLogged(log, "error: ESP-01: Alexa.LockController.Lock refused as INVALID_DIRECTIVE: "
                      "the device has no such capability");
}

void test_instance_the_device_lacks_is_answered_with_invalid_directive(void)
{
    FakeTransport transport;
    AlexaDevice blind("Blind", "root", "ESP-01", &transport);
    blind.addCapability(AlexaInterfaces::RangeController, "Blind.Lift");
    blind.onDirective(onDirective);
    handlerAnswers = false;

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa.RangeController", "SetRangeValue", "Blind.Tilt");
    blind.handleDirective(message);

    TEST_ASSERT_NULL(seen.capability);
    TEST_ASSERT_EQUAL(1, transport.sent.size());
    assertErrorResponse(transport.sent[0], "root/ESP-01/alexaResponce");
}

void test_answer_of_the_handler_to_an_interface_the_device_lacks_is_the_only_answer(void)
{
    FakeTransport transport;
    AlexaDevice lamp("Lamp", "root", "ESP-01", &transport);
    lamp.addCapability(AlexaInterfaces::PowerController);
    lamp.onDirective(onDirective);

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa.LockController", "Lock");
    lamp.handleDirective(message);

    TEST_ASSERT_EQUAL(1, transport.sent.size());
    JsonDocument answer;
    TEST_ASSERT_TRUE(deserializeJson(answer, transport.sent[0].json) == DeserializationError::Ok);
    TEST_ASSERT_EQUAL_STRING("Response", answer["event"]["header"]["name"] | "");
}

void test_device_without_a_handler_answers_with_invalid_directive(void)
{
    CapturedLog log;
    AlexaLog::setOutput(&log);
    FakeTransport transport;
    AlexaDevice lamp("Lamp", "root", "ESP-01", &transport);
    lamp.addCapability(AlexaInterfaces::PowerController);

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa.PowerController", "TurnOn");
    lamp.handleDirective(message);
    directiveFor(message, "ESP-01", "Alexa", "ReportState");
    lamp.handleDirective(message);

    TEST_ASSERT_EQUAL(2, transport.sent.size());
    assertErrorResponse(transport.sent[0], "root/ESP-01/alexaResponce");
    assertErrorResponse(transport.sent[1], "root/ESP-01/alexaResponce");
    assertLogged(log, "error: ESP-01: Alexa.PowerController.TurnOn refused as INVALID_DIRECTIVE: "
                      "the device has no handler, give it one with onDirective()");
}

void test_handler_that_sends_nothing_for_a_capability_of_the_device_is_reported(void)
{
    CapturedLog log;
    AlexaLog::setOutput(&log);
    FakeTransport transport;
    AlexaDevice lamp("Lamp", "root", "ESP-01", &transport);
    lamp.addCapability(AlexaInterfaces::PowerController);
    lamp.onDirective(onDirective);
    handlerAnswers = false;

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa.PowerController", "TurnOn");
    lamp.handleDirective(message);

    TEST_ASSERT_EQUAL(1, seen.calls);
    TEST_ASSERT_EQUAL(0, transport.sent.size());
    assertLogged(log, "error: ESP-01: the handler sent no answer to Alexa.PowerController.TurnOn");
}

void test_handlers_of_1x_get_report_state_and_the_type_of_every_other_directive(void)
{
    FakeTransport transport;
    AlexaDevice blind("Blind", "root", "ESP-01", &transport);
    blind.addCapability(AlexaInterfaceType::POWER_CONTROLLER);
    blind.addCapability(AlexaInterfaceType::TOGGLE_CONTROLLER)->setInstance("ESP-01.Toggle");
    blind.registerEvent("ReportState", onReportState);
    blind.registerEvent("Event", onEvent);

    JsonDocument message;
    directiveFor(message, "ESP-01", "Alexa.ToggleController", "TurnOn", "ESP-01.Toggle");
    blind.handleDirective(message);
    TEST_ASSERT_EQUAL(1, eventCalls);
    TEST_ASSERT_EQUAL(0, reportStateCalls);
    TEST_ASSERT_TRUE(AlexaInterfaceType::TOGGLE_CONTROLLER == eventType);

    directiveFor(message, "ESP-01", "Alexa", "ReportState");
    blind.handleDirective(message);
    TEST_ASSERT_EQUAL(1, eventCalls);
    TEST_ASSERT_EQUAL(1, reportStateCalls);

    // With a handler of 2.0 the device calls that one
    blind.onDirective(onDirective);
    directiveFor(message, "ESP-01", "Alexa.PowerController", "TurnOff");
    blind.handleDirective(message);
    TEST_ASSERT_EQUAL(1, eventCalls);
    TEST_ASSERT_EQUAL(1, seen.calls);
}

int main(int, char **)
{
    UNITY_BEGIN();
    RUN_TEST(test_devices_are_found_by_their_endpoint_id_in_the_order_they_were_created);
    RUN_TEST(test_one_handler_serves_two_devices_and_is_told_which);
    RUN_TEST(test_directive_with_an_instance_reaches_the_capability_with_that_instance);
    RUN_TEST(test_report_state_is_handed_over_without_a_capability_and_answered_with_a_state_report);
    RUN_TEST(test_one_capability_more_than_a_device_holds_is_refused_with_an_error);
    RUN_TEST(test_directive_for_an_interface_the_device_lacks_is_answered_with_invalid_directive);
    RUN_TEST(test_instance_the_device_lacks_is_answered_with_invalid_directive);
    RUN_TEST(test_answer_of_the_handler_to_an_interface_the_device_lacks_is_the_only_answer);
    RUN_TEST(test_device_without_a_handler_answers_with_invalid_directive);
    RUN_TEST(test_handler_that_sends_nothing_for_a_capability_of_the_device_is_reported);
    RUN_TEST(test_handlers_of_1x_get_report_state_and_the_type_of_every_other_directive);
    return UNITY_END();
}