#!/usr/bin/env python3
"""Turn bench.py result files into the standard speed report table.

    Dataset | Context | Input Tokens | Output Tokens | Prefill (tok/s) | TTFT (s) | Decode (tok/s) | E2E Latency (s)

One row per (dataset, context tier); every value is the mean over that tier's samples.
Failed requests (error != null) are excluded from the means and counted in a trailing note.

Usage:
  python report.py results/bench_32_165_*.json [--out report.md]
  python report.py                 # default: every results/*.json
"""
import argparse
import glob
import json
import os
import statistics as st

HERE = os.path.dirname(os.path.abspath(__file__))
TIER_ORDER = {'1k': 0, '4k': 1, '64k': 2, '128k': 3}
COLUMNS = ('Dataset', 'Context', 'Input Tokens', 'Output Tokens', 'Prefill (tok/s)',
           'TTFT (s)', 'Decode (tok/s)', 'E2E Latency (s)')


def load_rows(paths: list) -> list:
    rows = []
    for path in paths:
        with open(path) as fh:
            payload = json.load(fh)
        for r in payload.get('results', []):
            r.setdefault('tier', r.get('scale') or f"{r.get('length', 0) // 1024}k")
            r.setdefault('task_family', payload.get('dataset') or 'all')
            rows.append(r)
    return rows


def mean(values: list) -> float:
    values = [v for v in values if v is not None]
    return st.mean(values) if values else float('nan')


def build_table(rows: list) -> list:
    groups: dict = {}
    errors: dict = {}
    for r in rows:
        key = (r.get('task_family') or 'all', r.get('tier') or '?')
        (groups if not r.get('error') else errors).setdefault(key, []).append(r)
    table = []
    for key in sorted(groups, key=lambda k: (k[0], TIER_ORDER.get(k[1], 9), k[1])):
        g = groups[key]
        table.append({
            'Dataset': key[0],
            'Context': key[1],
            'Input Tokens': round(mean([r.get('prompt_tokens') for r in g])),
            'Output Tokens': round(mean([r.get('completion_tokens') for r in g])),
            'Prefill (tok/s)': round(mean([r.get('prefill_tok_s') for r in g]), 1),
            'TTFT (s)': round(mean([r.get('ttft_s') for r in g]), 2),
            'Decode (tok/s)': round(mean([r.get('decode_tok_s') for r in g]), 1),
            'E2E Latency (s)': round(mean([r.get('wall_s') for r in g]), 2),
            'n': len(g),
            'errors': len(errors.get(key, [])),
        })
    return table


def render(table: list) -> str:
    lines = ['| ' + ' | '.join(COLUMNS) + ' |', '|' + '|'.join(['---'] * len(COLUMNS)) + '|']
    for row in table:
        lines.append('| ' + ' | '.join(str(row[c]) for c in COLUMNS) + ' |')
    return '\n'.join(lines)


def main() -> None:
    ap = argparse.ArgumentParser()
    ap.add_argument('results', nargs='*')
    ap.add_argument('--out')
    a = ap.parse_args()

    paths = a.results or sorted(glob.glob(os.path.join(HERE, 'results', '*.json')))
    paths = [p for p in paths if os.path.basename(p) not in ('config.json',)]
    if not paths:
        raise SystemExit('no result files found')

    table = build_table(load_rows(paths))
    text = render(table)
    print(text)
    bad = sum(row['errors'] for row in table)
    if bad:
        print(f'\n注：{bad} 条请求失败，未计入均值。')
    if a.out:
        with open(a.out, 'w') as fh:
            fh.write(text + '\n')
        print(f'\n-> {a.out}')


if __name__ == '__main__':
    main()