// electron/utils/readConfig.js

const fs = require('fs');
const path = require('path');
const { app } = require('electron');
const defaultConfig = require('./config.default');

const configPath = path.join(app.getPath("userData"),'config.default.json');

// Smart Shooter 5 的历史默认安装目录。用户目录里的旧配置会盖掉代码默认值，
// 只有仍停在这套出厂值时才自动切到 6；手动选过别的目录则保持不动。
const LEGACY_SMARTSHOOTER5 = {
  controlType: "SmartShooter",
  controlPath: "C:\\Program Files\\Smart Shooter 5",
}

function sameValue(a, b) {
  return JSON.stringify(a) === JSON.stringify(b)
}

// 用户目录只保留和 utils 默认值不同的项
function stripDefaults(overrides) {
  const next = { ...overrides }
  for (const key of Object.keys(next)) {
    if (Object.prototype.hasOwnProperty.call(defaultConfig, key) && sameValue(next[key], defaultConfig[key])) {
      delete next[key]
    }
  }
  return next
}

function overridesEqual(a, b) {
  const keys = new Set([...Object.keys(a || {}), ...Object.keys(b || {})])
  for (const key of keys) {
    if (!sameValue(a[key], b[key])) return false
  }
  return true
}

function readOverrides() {
  if (!fs.existsSync(configPath)) return {}
  const data = fs.readFileSync(configPath, 'utf8');
  const parsed = JSON.parse(data);
  if (!parsed || typeof parsed !== 'object' || Array.isArray(parsed)) return {}
  return parsed
}

function writeOverrides(overrides) {
  fs.writeFileSync(configPath, JSON.stringify(overrides, null, 2), 'utf8');
}

function migrateLegacySmartShooter(overrides) {
  if (!overrides || overrides.smartShooter6Migrated) return { overrides, changed: false }
  const merged = { ...defaultConfig, ...overrides }
  const stillFactoryDefault = merged.controlType === LEGACY_SMARTSHOOTER5.controlType
    && merged.controlPath === LEGACY_SMARTSHOOTER5.controlPath
  const next = { ...overrides, smartShooter6Migrated: true }
  if (!stillFactoryDefault) return { overrides: next, changed: true }
  next.controlType = defaultConfig.controlType
  next.controlPath = defaultConfig.controlPath
  next.SmartShooterPath = overrides.SmartShooterPath || LEGACY_SMARTSHOOTER5.controlPath
  next.SmartShooter6Path = defaultConfig.SmartShooter6Path
  return { overrides: next, changed: true }
}

/**
 * 读取配置：utils 里的默认值打底，用户目录里只覆盖改过的项
 */
function readConfigFile() {

  try {
    const overrides = readOverrides()
    const { overrides: migrated, changed } = migrateLegacySmartShooter(overrides)
    const stored = stripDefaults(migrated)
    if (changed || !overridesEqual(overrides, stored)) {
      writeOverrides(stored)
    }

    return {
      ...defaultConfig,
      ...stored,
    };
  } catch (error) {
    console.error('读取配置文件出错:', error);
    return null;
  }
}

/**
 * 一次写入多项调整。和默认值相同的项不写进用户目录
 */
function updateConfigFile(partial) {
  try {
    const next = { ...readOverrides() }
    for (const [key, value] of Object.entries(partial)) {
      if (Object.prototype.hasOwnProperty.call(defaultConfig, key) && sameValue(value, defaultConfig[key])) {
        delete next[key]
      } else {
        next[key] = value
      }
    }
    writeOverrides(stripDefaults(next))
    console.log(`成功写入配置项: ${Object.keys(partial).join(', ')}`);
  } catch (error) {
    console.error('写入配置文件出错:', error);
  }
}

/**
 * 写入配置文件
 * @param {string} key - 要写入的配置项键名
 * @param {*} value - 要写入的配置项值
 */
function writeConfigFile(key, value) {
  updateConfigFile({ [key]: value })
}

module.exports = {
  readConfigFile,
  writeConfigFile,
  updateConfigFile
};