#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""从串口日志采集 meas: 读数并填入执行卡 CALDATA 表。

用法：
    cal_collect.py --doc <执行卡路径> --sem ua --point 1 [--samples N] [--log <日志路径>]

自动读取 serial.log 最近 N 拍（默认 15），取中位数，写入 CALDATA 表对应行。
重复运行同一 --point 会覆盖旧值。
"""
import argparse
import re
import statistics
import sys
import time
from pathlib import Path


DEFAULT_LOG = ".dsh/skills/serial-assistant/scripts/state/serial.log"
SEM_FIELD = {"ua": "ua_mv", "un": "un_mv", "ia": "ia_mv"}


def read_median(log_path, sem, n_samples=15, min_val=None):
    field = SEM_FIELD.get(sem)
    if not field:
        print("ERROR: unknown sem %r (use ua/un/ia)" % sem)
        return None
    text = Path(log_path).read_text(encoding="utf-8", errors="replace")
    lines = text.strip().splitlines()
    meas = [l for l in lines if "meas:" in l and field + "=" in l]
    recent = meas[-n_samples * 2:] if len(meas) >= n_samples * 2 else meas
    vals = []
    for l in recent:
        m = re.search(field + r"=(\d+\.?\d*)", l)
        if m:
            v = float(m.group(1))
            if min_val is not None and v < min_val:
                continue
            vals.append(v)
    if not vals:
        return None
    return round(statistics.median(vals))


def update_caldata(doc_path, sem, point, value):
    text = Path(doc_path).read_text(encoding="utf-8")
    m = re.search(r"(<!--\s*CALDATA:BEGIN\s*-->.*?<!--\s*CALDATA:END\s*-->)", text, re.S)
    if not m:
        print("ERROR: no CALDATA markers in %s" % doc_path)
        return False
    block = m.group(1)
    pattern = r"(\|\s*%s\s*\|\s*%d\s*\|\s*)(\S*|)(\s*\|.*)" % (re.escape(sem), point)
    new_block, count = re.subn(pattern, r"\g<1>%d\3" % value, block)
    if count != 1:
        print("ERROR: expected 1 match for %s point %d, got %d" % (sem, point, count))
        return False
    text = text.replace(block, new_block)
    Path(doc_path).write_text(text, encoding="utf-8", newline="\n")
    return True


def main():
    ap = argparse.ArgumentParser(description="采集串口读数填入 CALDATA 表")
    ap.add_argument("--doc", required=True, help="执行卡文档路径")
    ap.add_argument("--sem", required=True, choices=["ua", "un", "ia"], help="通道")
    ap.add_argument("--point", required=True, type=int, help="点序号 (1-5)")
    ap.add_argument("--samples", type=int, default=15, help="采样拍数 (默认 15)")
    ap.add_argument("--log", default=DEFAULT_LOG, help="串口日志路径")
    ap.add_argument("--min-val", type=float, default=None,
                    help="过滤低于此值的读数（切换瞬态）")
    ap.add_argument("--wait", type=float, default=3.0,
                    help="等待新数据到达的秒数 (默认 3)")
    a = ap.parse_args()

    if a.point < 1 or a.point > 8:
        print("ERROR: point must be 1-8")
        return 1

    time.sleep(a.wait)
    med = read_median(a.log, a.sem, a.samples, a.min_val)
    if med is None:
        print("ERROR: no valid %s data in last %d samples" % (a.sem, a.samples))
        return 1

    print("%s point %d: %d mV/mA (median of %d samples)" % (a.sem, a.point, med, a.samples))

    if not update_caldata(a.doc, a.sem, a.point, med):
        return 1

    print("OK: updated CALDATA table in %s" % a.doc)
    return 0


if __name__ == "__main__":
    sys.exit(main())