// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#include <vespa/vespalib/testkit/test_kit.h>
#include <vespa/config/common/misc.h>
#include <vespa/config/common/configholder.h>
#include <vespa/config/subscription/configsubscription.h>
#include <config-my.h>
#include <thread>

using namespace config;

namespace {

struct SourceFixture
{
    int numClose;
    int numGetConfig;
    int numReload;
    SourceFixture()
        : numClose(0),
          numGetConfig(0),
          numReload(0)
    { }
};

struct MySource : public Source
{
    MySource(SourceFixture * src)
        : source(src)
    {}

    void getConfig() override { source->numGetConfig++; }
    void close() override { source->numClose++; }
    void reload(int64_t gen) override { (void) gen; source->numReload++; }

    SourceFixture * source;
};

struct SubscriptionFixture
{
    std::shared_ptr<IConfigHolder> holder;
    ConfigSubscription sub;
    SourceFixture src;
    SubscriptionFixture(const ConfigKey & key)
        : holder(new ConfigHolder()),
          sub(0, key, holder, std::make_unique<MySource>(&src))
    {
    }
};

vespalib::steady_time
deadline(vespalib::duration timeout) {
    return vespalib::steady_clock::now() + timeout;
}
}

TEST_FF("requireThatKeyIsReturned", ConfigKey("foo", "bar", "bim", "boo"), SubscriptionFixture(f1))
{
    ASSERT_TRUE(f1 == f2.sub.getKey());
}

TEST_F("requireThatUpdateReturns", SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
{
    f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(), 1, 1));
    ASSERT_TRUE(f1.sub.nextUpdate(0, deadline(0ms)));
    ASSERT_TRUE(f1.sub.hasChanged());
    ASSERT_EQUAL(1, f1.sub.getGeneration());
}

TEST_F("requireThatNextUpdateBlocks", SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
{
    ASSERT_FALSE(f1.sub.nextUpdate(0, deadline(0ms)));
    f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(), 1, 1));
    vespalib::Timer timer;
    ASSERT_FALSE(f1.sub.nextUpdate(1, deadline(500ms)));
    ASSERT_TRUE(timer.elapsed() > 400ms);
}

TEST_MT_F("requireThatNextUpdateReturnsWhenNotified", 2, SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
{
    if (thread_id == 0) {
        vespalib::Timer timer;
        f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(), 1, 1));
        ASSERT_TRUE(f1.sub.nextUpdate(2, deadline(5000ms)));
        ASSERT_TRUE(timer.elapsed() > 200ms);
    } else {
        std::this_thread::sleep_for(500ms);
        f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(), 1, 1));
    }
}


TEST_MT_F("requireThatNextUpdateReturnsInterrupted", 2, SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
{
    if (thread_id == 0) {
        vespalib::Timer timer;
        f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(), 1, 1));
        ASSERT_TRUE(f1.sub.nextUpdate(1, deadline(5000ms)));
        ASSERT_TRUE(timer.elapsed() > 300ms);
    } else {
        std::this_thread::sleep_for(500ms);
        f1.sub.close();
    }
}

TEST_F("Require that isChanged takes generation into account", SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
{
    f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(StringVector(), "a"), true, 1));
    ASSERT_TRUE(f1.sub.nextUpdate(0, deadline(0ms)));
    f1.sub.flip();
    ASSERT_EQUAL(1, f1.sub.getLastGenerationChanged());
    f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(StringVector(), "b"), true, 2));
    ASSERT_TRUE(f1.sub.nextUpdate(1, deadline(0ms)));
    f1.sub.flip();
    ASSERT_EQUAL(2, f1.sub.getLastGenerationChanged());
    f1.holder->handle(std::make_unique<ConfigUpdate>(ConfigValue(), false, 3));
    ASSERT_TRUE(f1.sub.nextUpdate(2, deadline(0ms)));
    f1.sub.flip();
    ASSERT_EQUAL(2, f1.sub.getLastGenerationChanged());
}

TEST_MAIN() { TEST_RUN_ALL(); }