"""
Test decoder frame rate in isolation without any processing.
"""

import time
import os
from dotenv import load_dotenv

import sys
sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))

from services.stream_decoder import StreamDecoderFactory

load_dotenv()

def main():
    GPU_ID = 0
    STREAM_URL = os.getenv('CAMERA_URL_1', 'rtsp://localhost:8554/test')
    MAX_FRAMES = 100

    print("=" * 80)
    print("Decoder Frame Rate Test (No Processing)")
    print("=" * 80)
    print(f"\nStream: {STREAM_URL}")
    print(f"Monitoring for {MAX_FRAMES} frames...\n")

    # Create decoder
    factory = StreamDecoderFactory(gpu_id=GPU_ID)
    decoder = factory.create_decoder(STREAM_URL, buffer_size=30)

    # Start decoder
    decoder.start()

    # Wait for connection
    print("Waiting for connection...")
    max_wait = 10
    waited = 0
    while not decoder.is_connected() and waited < max_wait:
        time.sleep(0.5)
        waited += 0.5

    if not decoder.is_connected():
        print(f"Failed to connect after {max_wait}s!")
        decoder.stop()
        return

    print(f"✓ Connected\n")
    print("Monitoring frame arrivals...")
    print("-" * 60)

    last_count = 0
    frame_times = []
    start_time = time.time()
    last_frame_time = start_time

    while decoder.get_frame_count() < MAX_FRAMES:
        current_count = decoder.get_frame_count()

        if current_count > last_count:
            current_time = time.time()
            interval = (current_time - last_frame_time) * 1000

            frame_times.append(interval)
            print(f"Frame {current_count:3d}: interval={interval:6.1f}ms")

            last_count = current_count
            last_frame_time = current_time

        time.sleep(0.001)  # 1ms poll

    # Stop decoder
    decoder.stop()

    # Analysis
    elapsed = time.time() - start_time
    actual_fps = MAX_FRAMES / elapsed

    print("\n" + "=" * 80)
    print("DECODER PERFORMANCE")
    print("=" * 80)
    print(f"\nFrames received: {MAX_FRAMES}")
    print(f"Time: {elapsed:.1f}s")
    print(f"Actual FPS: {actual_fps:.2f}")
    print(f"\nFrame Intervals:")
    print(f"  Min: {min(frame_times[1:]):.1f}ms")  # Skip first
    print(f"  Max: {max(frame_times[1:]):.1f}ms")
    print(f"  Avg: {sum(frame_times[1:])/len(frame_times[1:]):.1f}ms")
    print(f"  Expected (6 FPS): 166.7ms")

if __name__ == "__main__":
    main()