/* eslint-disable @typescript-eslint/no-require-imports */
import fs from 'fs'
import path from 'path'

import { NAMESPACE_CONFIG, NAMESPACES } from '../config'

/** 可用的规则（去除废弃的和 Prettier 的规则） */
let activeRules: string[] = []
let deprecatedRules: string[] = []
const prettierRules = [
  ...Object.keys(require('eslint-config-prettier').rules),
  ...Object.keys(require('eslint-config-prettier/@typescript-eslint').rules),
  ...Object.keys(require('eslint-config-prettier/babel').rules),
  ...Object.keys(require('eslint-config-prettier/flowtype').rules),
  ...Object.keys(require('eslint-config-prettier/react').rules),
  ...Object.keys(require('eslint-config-prettier/standard').rules),
  ...Object.keys(require('eslint-config-prettier/unicorn').rules),
  ...Object.keys(require('eslint-config-prettier/vue').rules),
]

// 填充 deprecatedRules 和 activeRules
Object.values(NAMESPACE_CONFIG).forEach(({ rulePrefix, pluginName }) => {
  const ruleEntries = pluginName
    ? Object.entries<any>(require(pluginName).rules)
    : Array.from<any>(require('eslint/lib/rules').entries())
  ruleEntries.forEach(([ruleName, ruleValue]) => {
    const fullRuleName = rulePrefix + ruleName
    if (ruleValue.meta.deprecated) {
      deprecatedRules.push(fullRuleName)
      return
    }
    if (prettierRules.includes(fullRuleName)) {
      return
    }
    activeRules.push(fullRuleName)
  })
})

const errors: string[] = []
/** 可用的规则中，未使用的规则 */
const remainingRules = [...activeRules]

/**
 * 通过分析 test 目录下的文件，找出
 * 1. 使用了已废弃的规则
 * 2. 使用了 Prettier 的规则
 * 3. 可用的规则没有被使用
 */
NAMESPACES.forEach((namespace) => {
  fs.readdirSync(path.resolve(__dirname, '../test', namespace))
    .filter((ruleName) => fs.lstatSync(path.resolve(__dirname, '../test', namespace, ruleName)).isDirectory())
    .forEach((ruleName) => {
      const fullRuleName = NAMESPACE_CONFIG[namespace].rulePrefix + ruleName
      if (deprecatedRules.includes(fullRuleName)) {
        errors.push(`${fullRuleName} is deprecated, please REMOVE it`)
        return
      }
      if (prettierRules.includes(fullRuleName)) {
        errors.push(`${fullRuleName} is ignored by prettier, please REMOVE it`)
        return
      }
      if (activeRules.includes(fullRuleName)) {
        remainingRules.splice(remainingRules.indexOf(fullRuleName), 1)
      }
    })
})

if (remainingRules.length > 0) {
  errors.push(
    `Missing rules: ${remainingRules
      .map((ruleName) => `\n  - ${ruleName} ${getDocsUrlFromRuleName(ruleName)}`)
      .join('')}`,
  )
}

if (errors.length > 0) {
  throw new Error(errors.map((error) => `\n- ${error}`).join(''))
}

function getDocsUrlFromRuleName(ruleName: string) {
  for (const namespaceConfig of Object.values(NAMESPACE_CONFIG).reverse()) {
    const { rulePrefix, getDocsUrl } = namespaceConfig
    if (ruleName.startsWith(rulePrefix)) {
      return getDocsUrl(ruleName)
    }
  }
}