// This file is part of the 64k demo project.
// It tests tracker timing and synchronization using MockAudioBackend.
// Verifies pattern triggers occur at correct times with proper BPM scaling.

#include "audio/mock_audio_backend.h"
#include "audio/audio.h"
#include "audio/synth.h"
#include "audio/tracker.h"
#include <assert.h>
#include <stdio.h>
#include <cmath>

#if !defined(STRIP_ALL)

// Helper: Check if a timestamp exists in events within tolerance
static bool has_event_at_time(const std::vector<VoiceTriggerEvent>& events,
                               float expected_time, float tolerance = 0.001f) {
  for (const auto& evt : events) {
    if (std::abs(evt.timestamp_sec - expected_time) < tolerance) {
      return true;
    }
  }
  return false;
}

// Helper: Count events at a specific time
static int count_events_at_time(const std::vector<VoiceTriggerEvent>& events,
                                 float expected_time, float tolerance = 0.001f) {
  int count = 0;
  for (const auto& evt : events) {
    if (std::abs(evt.timestamp_sec - expected_time) < tolerance) {
      count++;
    }
  }
  return count;
}

// Helper: Get all unique timestamps in events
static std::vector<float> get_unique_timestamps(
    const std::vector<VoiceTriggerEvent>& events, float tolerance = 0.001f) {
  std::vector<float> timestamps;
  for (const auto& evt : events) {
    bool found = false;
    for (float ts : timestamps) {
      if (std::abs(evt.timestamp_sec - ts) < tolerance) {
        found = true;
        break;
      }
    }
    if (!found) {
      timestamps.push_back(evt.timestamp_sec);
    }
  }
  return timestamps;
}

void test_basic_event_recording() {
  printf("Test: Basic event recording with mock backend...\n");

  MockAudioBackend backend;
  audio_set_backend(&backend);

  tracker_init();
  synth_init();

  // Trigger at t=0.0 (should trigger initial patterns)
  tracker_update(0.0f);

  const auto& events = backend.get_events();
  printf("  Events triggered at t=0.0: %zu\n", events.size());

  // Verify we got some events
  assert(events.size() > 0);

  // All events at t=0 should have timestamp near 0
  for (const auto& evt : events) {
    assert(evt.timestamp_sec < 0.1f); // Within 100ms of start
  }

  printf("  ✓ Basic event recording works\n");
}

void test_progressive_triggering() {
  printf("Test: Progressive pattern triggering...\n");

  MockAudioBackend backend;
  audio_set_backend(&backend);

  tracker_init();
  synth_init();

  // Update at t=0
  tracker_update(0.0f);
  const size_t events_at_0 = backend.get_events().size();
  printf("  Events at t=0.0: %zu\n", events_at_0);

  // Update at t=1.0
  tracker_update(1.0f);
  const size_t events_at_1 = backend.get_events().size();
  printf("  Events at t=1.0: %zu\n", events_at_1);

  // Update at t=2.0
  tracker_update(2.0f);
  const size_t events_at_2 = backend.get_events().size();
  printf("  Events at t=2.0: %zu\n", events_at_2);

  // Events should accumulate (or at least not decrease)
  assert(events_at_1 >= events_at_0);
  assert(events_at_2 >= events_at_1);

  printf("  ✓ Events accumulate over time\n");
}

void test_simultaneous_triggers() {
  printf("Test: SIMULTANEOUS pattern triggers at same time...\n");

  MockAudioBackend backend;
  audio_set_backend(&backend);

  tracker_init();
  synth_init();

  // Clear and update to first trigger point
  backend.clear_events();
  tracker_update(0.0f);

  const auto& events = backend.get_events();
  if (events.size() == 0) {
    printf("  No events at t=0.0, skipping test\n");
    return;
  }

  // Check if we have multiple events at t=0
  const int simultaneous_count = count_events_at_time(events, 0.0f, 0.001f);
  printf("  Simultaneous events at t=0.0: %d out of %zu total\n",
         simultaneous_count, events.size());

  if (simultaneous_count > 1) {
    // Verify all simultaneous events have EXACTLY the same timestamp
    const float first_timestamp = events[0].timestamp_sec;
    float max_delta = 0.0f;

    for (size_t i = 1; i < events.size(); ++i) {
      const float delta = std::abs(events[i].timestamp_sec - first_timestamp);
      max_delta = std::fmaxf(max_delta, delta);
    }

    printf("  Maximum timestamp delta: %.6f seconds (%.3f ms)\n", max_delta,
           max_delta * 1000.0f);

    // Simultaneous events should have sub-millisecond timing
    assert(max_delta < 0.001f); // Less than 1ms difference

    printf("  ✓ All simultaneous events within 1ms of each other\n");
  } else {
    printf("  ℹ Only one event at t=0.0, cannot verify simultaneity\n");
  }
}

void test_timing_monotonicity() {
  printf("Test: Event timestamps are monotonically increasing...\n");

  MockAudioBackend backend;
  audio_set_backend(&backend);

  tracker_init();
  synth_init();

  // Update through several time points
  for (float t = 0.0f; t <= 5.0f; t += 0.5f) {
    tracker_update(t);
  }

  const auto& events = backend.get_events();
  printf("  Total events recorded: %zu\n", events.size());

  // Verify timestamps are monotonically increasing (non-decreasing)
  for (size_t i = 1; i < events.size(); ++i) {
    assert(events[i].timestamp_sec >= events[i - 1].timestamp_sec);
  }

  printf("  ✓ All timestamps monotonically increasing\n");
}

void test_seek_simulation() {
  printf("Test: Seek/fast-forward simulation...\n");

  MockAudioBackend backend;
  audio_set_backend(&backend);

  audio_init();
  tracker_init();
  synth_init();

  // Simulate seeking to t=3.0s by rendering silent audio
  // This should trigger all patterns in range [0, 3.0]
  const float seek_target = 3.0f;

  // Update tracker progressively (simulating real playback)
  float t = 0.0f;
  const float step = 0.1f;
  while (t <= seek_target) {
    tracker_update(t);
    // Simulate audio rendering
    float dummy_buffer[512 * 2];
    synth_render(dummy_buffer, 512);
    t += step;
  }

  const auto& events = backend.get_events();
  printf("  Events triggered during seek to %.1fs: %zu\n", seek_target,
         events.size());

  // Should have triggered multiple patterns
  assert(events.size() > 0);

  // All events should be before seek target time
  for (const auto& evt : events) {
    // Events can be slightly after due to synth processing
    assert(evt.timestamp_sec <= seek_target + 0.5f);
  }

  audio_shutdown();

  printf("  ✓ Seek simulation works correctly\n");
}

void test_timestamp_clustering() {
  printf("Test: Analyzing timestamp clustering...\n");

  MockAudioBackend backend;
  audio_set_backend(&backend);

  tracker_init();
  synth_init();

  // Update through the first 4 seconds
  for (float t = 0.0f; t <= 4.0f; t += 0.1f) {
    tracker_update(t);
  }

  const auto& events = backend.get_events();
  printf("  Total events: %zu\n", events.size());

  // Get unique timestamps
  auto unique_timestamps = get_unique_timestamps(events, 0.001f);
  printf("  Unique trigger times: %zu\n", unique_timestamps.size());

  // For each unique timestamp, count how many events occurred
  for (float ts : unique_timestamps) {
    const int count = count_events_at_time(events, ts, 0.001f);
    if (count > 1) {
      printf("  %.3fs: %d simultaneous events\n", ts, count);
    }
  }

  printf("  ✓ Timestamp clustering analyzed\n");
}

void test_render_integration() {
  printf("Test: Integration with audio_render_silent...\n");

  MockAudioBackend backend;
  audio_set_backend(&backend);

  audio_init();
  tracker_init();
  synth_init();

  // Trigger some patterns
  tracker_update(0.0f);
  const size_t events_before = backend.get_events().size();

  // Render 1 second of silent audio
  audio_render_silent(1.0f);

  // Check that backend time advanced
  const float backend_time = backend.get_current_time();
  printf("  Backend time after 1s render: %.3fs\n", backend_time);
  assert(backend_time >= 0.9f && backend_time <= 1.1f);

  // Trigger more patterns after time advance
  tracker_update(1.0f);
  const size_t events_after = backend.get_events().size();

  printf("  Events before: %zu, after: %zu\n", events_before, events_after);
  assert(events_after >= events_before);

  audio_shutdown();

  printf("  ✓ audio_render_silent integration works\n");
}

#endif /* !defined(STRIP_ALL) */

int main() {
#if !defined(STRIP_ALL)
  printf("Running Tracker Timing tests...\n\n");
  test_basic_event_recording();
  test_progressive_triggering();
  test_simultaneous_triggers();
  test_timing_monotonicity();
  test_seek_simulation();
  test_timestamp_clustering();
  test_render_integration();
  printf("\n✅ All Tracker Timing tests PASSED\n");
  return 0;
#else
  printf("Tracker Timing tests skipped (STRIP_ALL enabled)\n");
  return 0;
#endif /* !defined(STRIP_ALL) */
}