// SPDX-License-Identifier: MPL-2.0
#include "sequa/core/server/runtime.hpp"

#include <doctest/doctest.h>

#include <chrono>
#include <filesystem>
#include <thread>

using namespace sequa::core::server;
using namespace std::chrono_literals;
using Reason = CoreRuntime::ExitReason;

namespace {

CoreRuntimeOptions fast(bool linked)
{
    CoreRuntimeOptions options;
    options.linked = linked;
    options.real_time = false;
    options.lease_grace = 50ms;
    options.attach_deadline = 100ms;
    options.shutdown_delay = 20ms;
    options.core_version = "test";
    // Options de rendu pour les tests : racine dans un dossier temporaire vide (pas de sequa-render).
    options.sequa_root = std::filesystem::temp_directory_path() / "sequa_test_empty";
    options.render_core_url = "ws://127.0.0.1:9100/?token=test";
    options.render_log = "";
    options.log = [](std::string_view) {};
    return options;
}

void wait_past(std::chrono::milliseconds duration)
{
    std::this_thread::sleep_for(duration + 30ms);
}

} // namespace

TEST_CASE("Runtime : instanceId aleatoire de 32 hex, pid renseigne")
{
    const CoreRuntime a(fast(false));
    const CoreRuntime b(fast(false));
    const auto id = a.core_status().instance_id;
    CHECK(id.size() == 32);
    CHECK(id.find_first_not_of("0123456789abcdef") == std::string::npos);
    CHECK(id != b.core_status().instance_id);
    CHECK(a.core_status().pid > 0);
}

TEST_CASE("Runtime : sans --linked, pas de bail et pas d'arret")
{
    CoreRuntime runtime(fast(false));
    CHECK_FALSE(runtime.core_status().linked);
    wait_past(100ms);
    CHECK(runtime.exit_reason() == Reason::none);
}

TEST_CASE("Runtime : --linked sans controleur -> bail expire")
{
    CoreRuntime runtime(fast(true));
    CHECK(runtime.core_status().linked);
    CHECK(runtime.exit_reason() == Reason::none);
    wait_past(100ms);
    CHECK(runtime.exit_reason() == Reason::lease_expired);
}

TEST_CASE("Runtime : perte du controleur -> arret apres le delai de grace, sauf rattachement")
{
    CoreRuntime runtime(fast(true));
    runtime.on_client_connected();
    REQUIRE(runtime.attach(1, false) == CoreServices::AttachResult::attached);
    wait_past(100ms); // le délai de démarrage ne s'applique plus
    CHECK(runtime.exit_reason() == Reason::none);

    SUBCASE("personne ne revient")
    {
        runtime.on_client_disconnected(1);
        CHECK(runtime.exit_reason() == Reason::none);
        wait_past(50ms);
        CHECK(runtime.exit_reason() == Reason::lease_expired);
    }
    SUBCASE("un nouveau controleur s'attache pendant la grace (rechargement)")
    {
        runtime.on_client_disconnected(1);
        runtime.on_client_connected();
        REQUIRE(runtime.attach(2, false) == CoreServices::AttachResult::attached);
        wait_past(50ms);
        CHECK(runtime.exit_reason() == Reason::none);
    }
}

TEST_CASE("Runtime : detach puis deconnexion -> pas d'arret ; attach retablit le bail")
{
    CoreRuntime runtime(fast(true));
    REQUIRE(runtime.attach(1, false) == CoreServices::AttachResult::attached);
    CHECK(runtime.detach(2) == CoreServices::DetachResult::not_controller);
    REQUIRE(runtime.detach(1) == CoreServices::DetachResult::detached);
    CHECK_FALSE(runtime.core_status().linked);
    runtime.on_client_disconnected(1);
    wait_past(100ms);
    CHECK(runtime.exit_reason() == Reason::none);

    // Réversible : un nouveau Studio se rattache, le bail revient.
    REQUIRE(runtime.attach(3, false) == CoreServices::AttachResult::attached);
    CHECK(runtime.core_status().linked);
    runtime.on_client_disconnected(3);
    wait_past(50ms);
    CHECK(runtime.exit_reason() == Reason::lease_expired);
}

TEST_CASE("Runtime : core/shutdown -> arret apres un court delai")
{
    CoreRuntime runtime(fast(false));
    runtime.request_shutdown();
    CHECK(runtime.exit_reason() == Reason::none); // la réponse doit pouvoir partir
    wait_past(20ms);
    CHECK(runtime.exit_reason() == Reason::shutdown);
}

TEST_CASE("Runtime : comptage des clients")
{
    CoreRuntime runtime(fast(false));
    runtime.on_client_connected();
    runtime.on_client_connected();
    runtime.on_client_disconnected(9);
    CHECK(runtime.core_status().clients == 1);
}

// --- Tests du rendu (protocole 0.3) ---

TEST_CASE("Runtime : render_start avec sequa_root vide -> render-unavailable")
{
    CoreRuntimeOptions opts = fast(false);
    opts.sequa_root = ""; // racine inconnue
    CoreRuntime runtime(opts);

    RenderStartRequest req;
    req.adapter = "debug";
    const auto result = runtime.render_start(req);
    CHECK(!result.error_code.empty());
    CHECK(result.error_code == "render-unavailable");
    CHECK_FALSE(result.status.has_value());
}

TEST_CASE("Runtime : render_status stopped par defaut")
{
    CoreRuntime runtime(fast(false));

    const auto view = runtime.render_status();
    CHECK(view.state == RenderRunState::stopped);
    CHECK(!view.adapter.has_value());
    CHECK(!view.pid.has_value());
    CHECK(view.restarts == 0);
    CHECK(!view.engine.has_value());
    CHECK(!view.width.has_value());
    CHECK(!view.height.has_value());
    CHECK(!view.measurements.has_value());
    CHECK(view.world_version == 0);
    CHECK(!view.last_failure.has_value());
}

TEST_CASE("Runtime : render_stop sans rendu -> stopped")
{
    CoreRuntime runtime(fast(false));

    const auto view = runtime.render_stop();
    CHECK(view.state == RenderRunState::stopped);
    CHECK(!view.adapter.has_value());
    CHECK(!view.pid.has_value());
}

TEST_CASE("Runtime : render_start adapter inconnu -> render-unavailable")
{
    CoreRuntime runtime(fast(false));

    RenderStartRequest req;
    req.adapter = "inconnu";
    const auto result = runtime.render_start(req);
    CHECK(result.error_code == "render-unavailable");
    CHECK(result.error_message.find("Adaptateur inconnu") != std::string::npos);
}

TEST_CASE("Runtime : render_start puis render_stop -> stopped")
{
    CoreRuntime runtime(fast(false));

    // Sans exécutable réel, render_start échoue avec render-unavailable.
    // On teste juste que l'appel ne plante pas et retourne une erreur structurée.
    RenderStartRequest req;
    req.adapter = "debug";
    const auto start_result = runtime.render_start(req);
    CHECK(start_result.error_code == "render-unavailable");

    // render_stop doit quand même fonctionner et retourner stopped.
    const auto stop_view = runtime.render_stop();
    CHECK(stop_view.state == RenderRunState::stopped);
}