#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
运行目录定位与设置持久化(BASE_DIR 语义与 DLPilot config.py 一致)
==================================================================
frozen(PyInstaller onefile)时 BASE_DIR=exe 所在目录(sys.executable),
源码运行时=config.py 所在目录(即 src/)。设置写/读自 BASE_DIR 平铺的
serial_mate.json, 不建子目录。

读容错: 文件缺失/损坏/缺键一律回落默认值, 并保证返回的 dict 键全齐,
GUI 无需判空。
"""

import json
import os
import shutil
import sys

if getattr(sys, 'frozen', False):
    BASE_DIR = os.path.dirname(os.path.abspath(sys.executable))
else:
    BASE_DIR = os.path.dirname(os.path.abspath(__file__))

CONFIG_FILE = os.path.join(BASE_DIR, 'serial_mate.json')
LEGACY_CONFIG = os.path.join(BASE_DIR, 'serial_assistant.json')   # 更名前的配置
PROFILES_FILE = os.path.join(BASE_DIR, 'board_profiles.json')


def _migrate_legacy_config():
    """SerialAssistant -> SerialMate 更名迁移: 旧配置搬为新名(一次性, 已存在则跳过)"""
    if os.path.exists(CONFIG_FILE) or not os.path.exists(LEGACY_CONFIG):
        return
    try:
        shutil.copy2(LEGACY_CONFIG, CONFIG_FILE)
    except OSError:
        pass

DEFAULTS = {
    'serial': {'port': '', 'baud': 115200, 'bytesize': 8, 'parity': 'N', 'stopbits': 1},
    'proto': {'tx_hdr': 'D5', 'rx_hdr': 'B5', 'board': '01',
              'crc_algo': 'SUM8', 'crc_scope': 'no_header', 'parse': True,
              'layout': 'HDR ID LEN PAYLOAD CRC', 'len_sem': 'payload'},
    'tx': {'mode': 'wrap', 'periodic': False, 'interval_ms': 1000, 'profile': ''},
    'rx': {'display': 'text', 'show_raw': True},
    'channels': [
        {'enabled': False, 'name': '通道1', 'mode': 'num', 'offset': 0,
         'fmt': 'u16be', 'index': 1, 'pattern': '(?<=:)\\d+', 'scale': 1.0},
        {'enabled': False, 'name': '通道2', 'mode': 'bin', 'offset': 0,
         'fmt': 's16be', 'index': 1, 'pattern': '(?<=:)\\d+', 'scale': 1.0},
        {'enabled': False, 'name': '通道3', 'mode': 'bin', 'offset': 0,
         'fmt': 'u16be', 'index': 1, 'pattern': '(?<=:)\\d+', 'scale': 1.0},
        {'enabled': False, 'name': '通道4', 'mode': 'bin', 'offset': 0,
         'fmt': 'u16be', 'index': 1, 'pattern': '(?<=:)\\d+', 'scale': 1.0},
    ],
}

# 板型档案的帧协议字段(不含 parse —— 解析开关是查看偏好, 不随板型走)
_PROFILE_PROTO_KEYS = ('tx_hdr', 'rx_hdr', 'board', 'layout', 'len_sem',
                       'crc_algo', 'crc_scope')

# 首个板型的命令预设(DLPilot 光机命令集, 全表见上游 protocols.md)
DEFAULT_COMMANDS = (
    ('握手', 'M1'), ('查版本', 'M999'),
    ('开光机', 'M730S0'), ('关光机', 'M730S1'),
    ('设光强', 'M731S100'), ('查电流', 'M732'),
    ('查DMD温度', 'M201'), ('查LAMP温度', 'M202'),
    ('TEC自动控温开', 'M7S0'), ('TEC自动控温关', 'M7S1'),
    ('凝露点33.0°C', 'M8S330'), ('软件重启', 'M888'),
)


def default_profiles():
    """首个板型档案: DLPilot 光机(协议字段取默认值)"""
    return [{'name': 'DLPilot光机',
             'proto': {k: DEFAULTS['proto'][k] for k in _PROFILE_PROTO_KEYS},
             'commands': [list(c) for c in DEFAULT_COMMANDS]}]


def _merge(base, over):
    """递归覆盖: over 缺键用 base 补齐, over 多余键保留(向前兼容旧配置)"""
    out = dict(base)
    for k, v in over.items():
        if k in base and isinstance(base[k], dict) and isinstance(v, dict):
            out[k] = _merge(base[k], v)
        else:
            out[k] = v
    return out


def load():
    _migrate_legacy_config()
    """读设置; 任何异常回落默认(键全齐), 不抛出"""
    try:
        with open(CONFIG_FILE, encoding='utf-8') as f:
            data = json.load(f)
        if not isinstance(data, dict):
            raise ValueError('配置根不是对象')
    except Exception:
        return json.loads(json.dumps(DEFAULTS))    # 深拷贝默认值
    return _merge(DEFAULTS, data)


def save(cfg):
    """写设置; 失败静默(只读目录等场景不阻塞退出)"""
    try:
        with open(CONFIG_FILE, 'w', encoding='utf-8') as f:
            json.dump(cfg, f, ensure_ascii=False, indent=1)
    except Exception:
        pass


def load_profiles():
    """读板型档案(board_profiles.json); 缺失/损坏回落默认并落盘。
    档案结构: {'profiles': [{'name', 'proto'{7字段}, 'commands'[[名,命令]..]}..]}"""
    try:
        with open(PROFILES_FILE, encoding='utf-8') as f:
            data = json.load(f)
        profiles = data.get('profiles') if isinstance(data, dict) else data
        if isinstance(profiles, list) and profiles:
            out = []
            for p in profiles:
                if not isinstance(p, dict) or not p.get('name'):
                    continue
                out.append({'name': str(p['name']),
                            'proto': {k: p.get('proto', {}).get(k,
                                      DEFAULTS['proto'][k])
                                      for k in _PROFILE_PROTO_KEYS},
                            'commands': [[str(n), str(c)]
                                         for n, c in p.get('commands', [])
                                         if isinstance(n, str) and isinstance(c, str)]})
            if out:
                return out
    except Exception:
        pass
    profiles = default_profiles()
    save_profiles(profiles)
    return profiles


def save_profiles(profiles):
    """写板型档案; 失败静默并返回 False"""
    try:
        with open(PROFILES_FILE, 'w', encoding='utf-8') as f:
            json.dump({'profiles': profiles}, f, ensure_ascii=False, indent=1)
        return True
    except Exception:
        return False