"""Read-only numeric performance samples; no device identity or WiFi payloads."""
import argparse
import json
from pathlib import Path
import shlex
from remote_support import connect, execute


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('--seconds', type=int, default=120)
    parser.add_argument('--output', type=Path, required=True)
    args = parser.parse_args()
    if not 5 <= args.seconds <= 600:
        parser.error('seconds must be 5..600')
    if args.output.exists():
        parser.error('output already exists; do not overwrite evidence')
    script = r'''
import json,time,urllib.request
rows=[]
start=time.monotonic()
while time.monotonic()-start < DURATION:
    with urllib.request.urlopen('http://127.0.0.1:8080/api/status',timeout=5) as response:
        s=json.load(response)
    d=s['screen']['driver_status'];r=s['resources']
    rows.append(dict(elapsed_seconds=round(time.monotonic()-start,3),
      connected=s['mobile']['connected'],animation_active=s['state']['animation_active'],
      refresh_hz=d['actual_refresh_rate_hz'],frames=d['completed_frames'],
      deadline_misses=d['deadline_misses'],oe_faults=d['oe_pulse_faults'],
      driver_error_present=bool(d['last_error'] or d['oe_timing_error']),
      cpu_application_percent=r['cpu']['application_percent'],
      memory_application_bytes=r['memory']['application_bytes']))
    time.sleep(1)
print(json.dumps(rows))
'''.replace('DURATION', str(args.seconds))
    client, fields = connect()
    try:
        code, output, _ = execute(client, 'python3 -c ' + shlex.quote(script), timeout=args.seconds + 20)
        if code:
            raise RuntimeError('Performance collection failed; raw output withheld')
        rows = json.loads(output)
        args.output.parent.mkdir(parents=True, exist_ok=True)
        with args.output.open('x', encoding='utf-8') as stream:
            json.dump(rows, stream, ensure_ascii=False, indent=2)
            stream.write('\n')
        print(json.dumps(dict(samples=len(rows),connected_samples=sum(r['connected'] for r in rows),
            deadline_misses_delta=rows[-1]['deadline_misses']-rows[0]['deadline_misses'],
            oe_faults_delta=rows[-1]['oe_faults']-rows[0]['oe_faults'],
            min_refresh_hz=min(r['refresh_hz'] for r in rows),
            driver_error_seen=any(r['driver_error_present'] for r in rows))))
    finally:
        client.close()


if __name__ == '__main__':
    main()