#include "../src/export.h"
#include <gtest/gtest.h>
#include <algorithm>
#include <array>
#include <limits>
#include <stdexcept>
namespace renderive {
namespace {
TEST(Renderive_Core2_Frame_Pipeline, ManualLifecycleSeparatesPrepareRefreshAndRender) {
    Manual_Scene2D plot;
    plot.init();
    plot.set_viewport_size({96, 54});
    ASSERT_TRUE(plot.prepare_frame());
    auto snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.mode, Frame_Control_Mode::Manual);
    EXPECT_EQ(snapshot.last_event, "prepared");
    EXPECT_EQ(snapshot.limit_state, "not_applicable");
    EXPECT_EQ(snapshot.produced_frame_count, 1u);
    EXPECT_EQ(snapshot.consumed_frame_count, 0u);
    EXPECT_EQ(snapshot.pending_frame_count, 1u);
    EXPECT_EQ(snapshot.latest_sequence, 1u);
    ASSERT_TRUE(plot.refresh_manual_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "refresh_succeeded");
    EXPECT_EQ(snapshot.produced_frame_count, 1u);
    EXPECT_EQ(snapshot.consumed_frame_count, 0u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 1u);
    ASSERT_TRUE(plot.render_prepared_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "rendered");
    EXPECT_EQ(snapshot.produced_frame_count, 1u);
    EXPECT_EQ(snapshot.consumed_frame_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 1u);
    EXPECT_EQ(plot.diagnostics().refresh.frame_count, 1u);
}
TEST(Renderive_Core2_Frame_Pipeline, HighFrequencyLowLatencyLifecycleExposesKernelTiming) {
    Scene2D plot;
    plot.init();
    plot.set_viewport_size({96, 54});
    plot.set_max_render_fps(1'000'000'000.0);
    ASSERT_TRUE(plot.prepare_frame());
    auto snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "published");
    EXPECT_EQ(snapshot.limit_state, "frequency_limited");
    EXPECT_DOUBLE_EQ(snapshot.frequency_hz, 1'000'000'000.0);
    EXPECT_EQ(snapshot.target_interval_ns, 1u);
    EXPECT_EQ(snapshot.produced_frame_count, 1u);
    EXPECT_EQ(snapshot.consumed_frame_count, 0u);
    EXPECT_EQ(snapshot.pending_frame_count, 1u);
    ASSERT_TRUE(plot.render_prepared_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "lifecycle_completed");
    EXPECT_DOUBLE_EQ(snapshot.frequency_hz, 1'000'000'000.0);
    EXPECT_EQ(snapshot.target_interval_ns, 1u);
    EXPECT_EQ(snapshot.produced_frame_count, 1u);
    EXPECT_EQ(snapshot.consumed_frame_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.bottleneck_duration_ns,
              std::max(snapshot.paint_duration_ns, snapshot.render_duration_ns));
    EXPECT_EQ(snapshot.next_refresh_interval_ns,
              std::max(snapshot.target_interval_ns, snapshot.bottleneck_duration_ns));
    EXPECT_GE(snapshot.end_to_end_ns, snapshot.paint_duration_ns);
    EXPECT_GE(snapshot.end_to_end_ns, snapshot.render_duration_ns);
    const auto refresh = plot.refresh_feedback_snapshot();
    EXPECT_DOUBLE_EQ(refresh.frequency_hz, snapshot.frequency_hz);
    EXPECT_EQ(refresh.frame_count, snapshot.consumed_frame_count);
    EXPECT_EQ(refresh.next_refresh_interval_ns, snapshot.next_refresh_interval_ns);
}
TEST(Renderive_Core2_Frame_Pipeline, LowLatencyConsumerFeedbackFlowsThroughCore2IntoKernelScheduling) {
    Scene2D plot;
    plot.init();
    plot.set_viewport_size({96, 54});
    plot.set_max_render_fps(100.0);
    plot.set_consumer_feedback({40'000'000});
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.render_prepared_frame());
    const auto snapshot = plot.frame_observer_snapshot();
    EXPECT_TRUE(snapshot.frequency_limit_enabled);
    EXPECT_TRUE(snapshot.consumer_feedback_enabled);
    EXPECT_EQ(snapshot.limit_state, "consumer_limited");
    EXPECT_EQ(snapshot.target_interval_ns, 10'000'000u);
    EXPECT_EQ(snapshot.consumer_sample_interval_ns, 40'000'000u);
    EXPECT_EQ(snapshot.consumer_smoothed_interval_ns, 40'000'000u);
    EXPECT_EQ(snapshot.consumer_variation_ns, 0u);
    EXPECT_EQ(snapshot.consumer_safety_interval_ns, 40'000'000u);
    EXPECT_EQ(snapshot.consumer_interval_ns, 40'000'000u);
    EXPECT_EQ(snapshot.next_refresh_interval_ns, 40'000'000u);
    EXPECT_EQ(plot.refresh_feedback_snapshot().next_refresh_interval_ns, 40'000'000u);
}
TEST(Renderive_Core2_Frame_Pipeline, LowLatencyLimitsCanBeClearedIndependently) {
    Scene2D plot;
    plot.init();
    plot.set_viewport_size({96, 54});
    plot.set_max_render_fps(100.0);
    plot.set_consumer_feedback({40'000'000});
    plot.clear_consumer_feedback();
    plot.clear_max_render_fps();
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.render_prepared_frame());
    const auto snapshot = plot.frame_observer_snapshot();
    EXPECT_FALSE(snapshot.frequency_limit_enabled);
    EXPECT_FALSE(snapshot.consumer_feedback_enabled);
    EXPECT_EQ(snapshot.target_interval_ns, 0u);
    EXPECT_EQ(snapshot.consumer_interval_ns, 0u);
    EXPECT_EQ(snapshot.next_refresh_interval_ns, snapshot.bottleneck_duration_ns);
    EXPECT_TRUE(snapshot.limit_state == "paint_limited" || snapshot.limit_state == "render_limited");
}
TEST(Renderive_Core2_Frame_Pipeline, LowLatencyReplacementRetiresOldFrameWithoutPhantomPendingFrame) {
    Scene2D plot;
    plot.init();
    plot.set_viewport_size({64, 40});
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.prepare_frame());
    auto snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "published");
    EXPECT_EQ(snapshot.produced_frame_count, 2u);
    EXPECT_EQ(snapshot.dropped_frame_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 1u);
    EXPECT_EQ(snapshot.latest_sequence, 2u);
    ASSERT_TRUE(plot.render_prepared_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "lifecycle_completed");
    EXPECT_EQ(snapshot.produced_frame_count, 2u);
    EXPECT_EQ(snapshot.consumed_frame_count, 1u);
    EXPECT_EQ(snapshot.dropped_frame_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 2u);
}
TEST(Renderive_Core2_Frame_Pipeline, LowLatencyDiscardAndEmptyRenderRemainObservable) {
    Scene2D plot;
    plot.init();
    plot.set_viewport_size({64, 40});
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.discard_pending_frame());
    auto snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "manually_discarded");
    EXPECT_EQ(snapshot.produced_frame_count, 1u);
    EXPECT_EQ(snapshot.consumed_frame_count, 0u);
    EXPECT_EQ(snapshot.dropped_frame_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 1u);
    EXPECT_FALSE(plot.render_prepared_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "swap_failed");
    EXPECT_EQ(snapshot.failed_operation_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 1u);
}
TEST(Renderive_Core2_Frame_Pipeline, ManualDiscardAndFailedRefreshUpdateObserverState) {
    Manual_Scene2D plot;
    plot.init();
    plot.set_viewport_size({64, 40});
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.discard_pending_frame());
    auto snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "manually_discarded");
    EXPECT_EQ(snapshot.produced_frame_count, 1u);
    EXPECT_EQ(snapshot.dropped_frame_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 1u);
    const auto last_paint_duration_ns = snapshot.paint_duration_ns;
    EXPECT_FALSE(plot.refresh_manual_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "refresh_failed");
    EXPECT_EQ(snapshot.failed_operation_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 1u);
    EXPECT_EQ(snapshot.paint_duration_ns, last_paint_duration_ns);
}
TEST(Renderive_Core2_Frame_Pipeline, PlaybackPreservesQueueDepthAndEmptyAcquireFailure) {
    Playback_Scene2D plot;
    plot.init();
    plot.set_viewport_size({64, 40});
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.prepare_frame());
    auto snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.produced_frame_count, 3u);
    EXPECT_EQ(snapshot.pending_frame_count, 3u);
    EXPECT_EQ(snapshot.latest_sequence, 3u);
    ASSERT_TRUE(plot.render_prepared_frame());
    ASSERT_TRUE(plot.render_prepared_frame());
    ASSERT_TRUE(plot.render_prepared_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "rendered");
    EXPECT_EQ(snapshot.consumed_frame_count, 3u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 3u);
    const auto last_paint_duration_ns = snapshot.paint_duration_ns;
    const auto last_render_duration_ns = snapshot.render_duration_ns;
    const auto last_queue_wait_ns = snapshot.queue_wait_ns;
    EXPECT_FALSE(plot.render_prepared_frame());
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.last_event, "queue_empty");
    EXPECT_EQ(snapshot.failed_operation_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 0u);
    EXPECT_EQ(snapshot.latest_sequence, 3u);
    EXPECT_EQ(snapshot.paint_duration_ns, last_paint_duration_ns);
    EXPECT_EQ(snapshot.render_duration_ns, last_render_duration_ns);
    EXPECT_EQ(snapshot.queue_wait_ns, last_queue_wait_ns);
}
TEST(Renderive_Core2_Frame_Pipeline, PlaybackFullCyclePreservesPreviouslyQueuedFrames) {
    Playback_Scene2D plot;
    plot.init();
    plot.set_viewport_size({96, 54});
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.prepare_frame());
    ASSERT_TRUE(plot.prepare_frame());
    auto snapshot = plot.frame_observer_snapshot();
    ASSERT_EQ(snapshot.pending_frame_count, 3u);
    ASSERT_EQ(snapshot.produced_frame_count, 3u);
    ASSERT_TRUE(plot.render_frame(true));
    snapshot = plot.frame_observer_snapshot();
    EXPECT_EQ(snapshot.mode, Frame_Control_Mode::Playback);
    EXPECT_EQ(snapshot.last_event, "rendered");
    EXPECT_EQ(snapshot.produced_frame_count, 4u);
    EXPECT_EQ(snapshot.consumed_frame_count, 1u);
    EXPECT_EQ(snapshot.pending_frame_count, 3u);
    // The cycle enqueues sequence 4 but must consume the FIFO head (sequence 1).
    EXPECT_EQ(snapshot.latest_sequence, 1u);
    EXPECT_FALSE(plot.discard_pending_frame());
    EXPECT_EQ(plot.frame_observer_snapshot().pending_frame_count, 3u);
}
TEST(Renderive_Core2_Frame_Pipeline, EveryModeHonorsActiveDirtyAndForceRenderGates) {
    const auto verify = []<class Scene_Type>(Frame_Control_Mode mode) {
        Scene_Type scene;
        scene.init();
        scene.set_viewport_size({80, 45});
        EXPECT_FALSE(scene.view_active());
        EXPECT_FALSE(scene.render_frame(false));
        EXPECT_EQ(scene.frame_observer_snapshot().observation_count, 0u);
        scene.activate_view();
        ASSERT_TRUE(scene.render_frame(false));
        const auto completed = scene.frame_observer_snapshot();
        EXPECT_EQ(completed.mode, mode);
        EXPECT_EQ(completed.consumed_frame_count, 1u);
        EXPECT_FALSE(scene.render_frame(false));
        EXPECT_EQ(scene.frame_observer_snapshot().consumed_frame_count, 1u);
        scene.deactivate_view();
        scene.set_background_color(Color{8, 16, 24, 255});
        EXPECT_FALSE(scene.render_frame(false));
        ASSERT_TRUE(scene.render_frame(true));
        EXPECT_EQ(scene.frame_observer_snapshot().consumed_frame_count, 2u);
    };
    verify.template operator()<Manual_Scene2D>(Frame_Control_Mode::Manual);
    verify.template operator()<Scene2D>(Frame_Control_Mode::Low_Latency);
    verify.template operator()<Playback_Scene2D>(Frame_Control_Mode::Playback);
}
TEST(Renderive_Core2_Frame_Pipeline, FrequencyConfigurationRejectsInvalidValuesAndWrongModes) {
    Scene2D low_latency;
    EXPECT_THROW(low_latency.set_max_render_fps(0.0), std::invalid_argument);
    EXPECT_THROW(low_latency.set_max_render_fps(-1.0), std::invalid_argument);
    EXPECT_THROW(low_latency.set_max_render_fps(std::numeric_limits<double>::quiet_NaN()),
                 std::invalid_argument);
    EXPECT_THROW(low_latency.set_max_render_fps(std::numeric_limits<double>::infinity()),
                 std::invalid_argument);
    low_latency.set_max_render_fps(1'000.0);
    EXPECT_DOUBLE_EQ(low_latency.max_render_fps(), 1'000.0);
    Manual_Scene2D manual;
    Playback_Scene2D playback;
    EXPECT_THROW(manual.set_max_render_fps(60.0), std::logic_error);
    EXPECT_THROW(playback.set_max_render_fps(60.0), std::logic_error);
    EXPECT_FALSE(playback.refresh_manual_frame());
    EXPECT_FALSE(playback.discard_pending_frame());
}
} // namespace
} // namespace renderive