#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""dlpc_rs485 协议自检(无硬件): 对照上游 protocols.md 的实测帧向量做回归

用法: python selftest_rs485.py   (全部通过退出码 0)
"""
import sys

import dlpc_rs485 as d

fails = []


def check(name, got, want):
    ok = got == want
    print(('PASS' if ok else 'FAIL'), name, '->', got, '' if ok else f'(期望 {want})')
    if not ok:
        fails.append(name)


# 1) 帧构造: protocols.md 实测示例 M730S0T2000
f = d.build_frame('M730S0T2000')
check('build_frame(M730S0T2000)', f.hex(' ').upper(),
      'D5 01 0B 4D 37 33 30 53 30 54 32 30 30 30 8C')

# 2) 增量解析: ok 应答跨两个半包喂入
p = d.FrameParser()
r1 = p.feed(bytes.fromhex('B5 F0'))
r2 = p.feed(bytes.fromhex('02 6F 6B CC'))
check('split-feed frames', len(r1) + len(r2), 1)
fr = (r1 + r2)[0]
check('type_code', fr.type_code, 0xF0)
check('payload', fr.payload, 'ok')
check('describe(ok)', d.describe(fr), 'ok')

# 3) 前导噪声 + 0xFD err:OL 译码(字符串标记, 不附 DLPC 释义)
body = bytes.fromhex('FD 06 65 72 72 3A 4F 4C')          # "err:OL"
good = bytes([0xB5]) + body + bytes([d.sum_crc(body)])
frames = d.FrameParser().feed(b'\x01\x02' + good)
check('noise+err-frame count', len(frames), 1)
check('describe(err:OL)', d.describe(frames[0]), '参数越界/读回复核不一致  err:OL')

# 4) 0xFA + 数字错误码 err:3 追加 DLPC 释义
body = bytes.fromhex('FA 05') + b'err:3'
fa = bytes([0xB5]) + body + bytes([d.sum_crc(body)])
frames = d.FrameParser().feed(fa)
check('describe(err:3)', d.describe(frames[0]),
      '开光机通信失败  err:3（I2C NACK(器件无应答)）')

# 5) CRC 坏帧被丢弃后继续同步到下一帧
bad = bytearray(good)
bad[-1] ^= 0xFF
frames = d.FrameParser().feed(bytes(bad) + good)
check('bad-crc then good', len(frames), 1)
check('recovered type', frames[0].type_code, 0xFD)

# 6) 非法输入拒绝
for bad_cmd in ('', '   '):
    try:
        d.build_frame(bad_cmd)
        fails.append('empty-cmd-not-rejected')
    except ValueError:
        pass
try:
    d.build_frame('M' * 40)
    fails.append('long-cmd-not-rejected')
except ValueError:
    pass
print('空/超长命令拒绝: PASS')

# 7) 预设命令全部可组帧
for _name, cmd, _note in d.PRESETS:
    d.build_frame(cmd)
print(f'预设 {len(d.PRESETS)} 条全部可组帧: PASS')

print('RESULT:', 'FAIL:' + ','.join(fails) if fails else 'ALL PASS')
sys.exit(1 if fails else 0)