import YAML from 'js-yaml'
import slug from 'limax'
import { PushCommit } from '@type-challenges/octokit-create-pull-request'
import type { Action, Context, Github, Quiz } from '../types'
import { t } from '../locales'
import { toPlaygroundUrl } from '../toUrl'
import { toBadgeLink } from '../readme'
import { resolveFilePath } from '../utils/resolve'
import { formatToCode } from './utils/formatToCode'

const Messages = {
  'en': {
    info: 'Info',
    template: 'Template',
    tests: 'Test Cases',
    issue_reply: '#{0} - Pull Request created.',
    issue_update_reply: '#{0} - Pull Request updated.',
    issue_invalid_reply:
      'Failed to parse the issue, please follow the template.',
    pr_auto_translate_tips: 'Auto translated by Google Translate',
  },
  'zh-CN': {
    info: '基本信息',
    template: '题目模版',
    tests: '判题测试',
    issue_reply: '#{0} - PR 已生成',
    issue_update_reply: '#{0} - PR 已更新',
    issue_invalid_reply: 'Issue 格式不正确，请按照依照模版修正',
    pr_auto_translate_tips: '通过谷歌 API 自动翻译',
  },
  'ja': {
    info: '基本情報',
    template: 'テンプレート',
    tests: 'テストケース',
    issue_reply: '#{0} - Pull Request created.',
    issue_update_reply: '#{0} - Pull Request updated.',
    issue_invalid_reply: 'Failed to parse the issue, please follow the template.',
    pr_auto_translate_tips: 'Auto translated by Google Translate',
  },
}

export const getOthers = <A, B>(condition: boolean, a: A, b: B): A | B => condition ? a : b

const action: Action = async (github, context, core) => {
  const payload = context.payload || {}
  const issue = payload.issue
  const no = context.issue.number

  if (!issue)
    return

  const labels: string[] = (issue.labels || [])
    .map((i: any) => i && i.name)
    .filter(Boolean)

  // create pr for new challenge
  if (labels.includes('new-challenge')) {
    const locale = labels.includes('ja') ? 'ja' : labels.includes('zh-CN') ? 'zh-CN' : 'en'

    const body = issue.body || ''
    const infoRaw = getCodeBlock(body, Messages[locale].info, 'yaml')
    const template = getCodeBlock(body, Messages[locale].template, 'ts')
    const tests = getCodeBlock(body, Messages[locale].tests, 'ts')
    const question = getCommentRange(body, 'question')

    let info: any

    try {
      info = YAML.load(infoRaw || '')
    }
    catch {
      info = null
    }

    core.info('-----Playload-----')
    core.info(JSON.stringify(context.payload, null, 2))

    // invalid issue
    if (!question || !template || !tests || !info) {
      await updateComment(
        github,
        context,
        Messages[locale].issue_invalid_reply,
      )
      return
    }

    const { data: user } = await github.rest.users.getByUsername({
      username: issue.user.login,
    })

    // allow user to override the author info when filled in the Issue
    if (!info.author) {
      info.author = info.author || {}
      info.author.github = issue.user.login
      if (user)
        info.author.name = user.name
    }

    core.info(`user: ${JSON.stringify(user)}`)
    core.info(`info: ${JSON.stringify(info)}`)

    const quiz: Quiz = {
      no,
      difficulty: info.difficulty,
      path: '',
      info: {
        [locale]: info,
      },
      template,
      tests,
      readme: {
        [locale]: question,
      },
    }

    core.info('-----Parsed-----')
    core.info(JSON.stringify(quiz, null, 2))

    const { data: pulls } = await github.rest.pulls.list({
      owner: context.repo.owner,
      repo: context.repo.repo,
      state: 'open',
    })

    const existing_pull = pulls.find(
      i => i.user?.login === 'github-actions[bot]' && i.title.startsWith(`#${no} `),
    )

    const dir = `questions/${String(no).padStart(5, '0')}-${info.difficulty}-${slug(
      info.title.replace(/\./g, '-').replace(/<.*>/g, ''),
      { tone: false },
    )}`
    const userEmail = `${user.id}+${user.login}@users.noreply.github.com`

    const files: Record<string, string> = {
      [resolveFilePath(dir, 'info', 'yml', locale)]: `${YAML.dump(info)}\n`,
      [resolveFilePath(dir, 'README', 'md', locale)]: `${question}\n`,
      [`${dir}/template.ts`]: `${template}\n`,
      [`${dir}/test-cases.ts`]: `${tests}\n`,
    }

    await PushCommit(github, {
      owner: context.repo.owner,
      repo: context.repo.repo,
      base: 'main',
      head: `pulls/${no}`,
      changes: {
        files,
        commit: `feat(question): add #${no} - ${info.title}`,
        author: {
          name: `${user.name || user.id || user.login}`,
          email: userEmail,
        },
      },
      fresh: !existing_pull,
    })

    const playgroundURL = toPlaygroundUrl(formatToCode(quiz, locale), info.tsconfig || {})

    const playgroundBadge = toBadgeLink(
      playgroundURL,
      '',
      t(locale, 'badge.preview-playground'),
      '3178c6',
      '?logo=typescript&logoColor=white',
    )
    const createMessageBody = (prNumber: number) =>
      `${Messages[locale].issue_update_reply.replace(
        '{0}',
        prNumber.toString(),
      )}\n\n${getTimestampBadge()}  ${playgroundBadge}`

    if (existing_pull) {
      core.info('-----Pull Request Existed-----')
      core.info(JSON.stringify(existing_pull, null, 2))
      await updateComment(
        github,
        context,
        createMessageBody(existing_pull.number),
      )
    }
    else {
      core.info('-----Creating PR-----')
      const { data: pr } = await github.rest.pulls.create({
        owner: context.repo.owner,
        repo: context.repo.repo,
        base: 'main',
        head: `pulls/${no}`,
        title: `#${no} - ${info.title}`,
        body: `This is an auto-generated PR that auto reflect on #${no}, please go to #${no} for discussion or making changes.\n\nCloses #${no}`,
        labels: ['auto-generated'],
      })

      await github.rest.issues.addLabels({
        owner: context.repo.owner,
        repo: context.repo.repo,
        issue_number: pr.number,
        labels: ['auto-generated'],
      })

      core.info('-----Pull Request-----')
      core.info(JSON.stringify(pr, null, 2))

      if (pr)
        await updateComment(github, context, createMessageBody(pr.number))
    }
  }
  else {
    core.info('No matched labels, skipped')
  }
}

async function updateComment(github: Github, context: Context, body: string) {
  const { data: comments } = await github.rest.issues.listComments({
    issue_number: context.issue.number,
    owner: context.repo.owner,
    repo: context.repo.repo,
  })

  const existing_comment = comments.find(
    i => i.user?.login === 'github-actions[bot]',
  )

  if (existing_comment) {
    return await github.rest.issues.updateComment({
      comment_id: existing_comment.id,
      issue_number: context.issue.number,
      owner: context.repo.owner,
      repo: context.repo.repo,
      body,
    })
  }
  else {
    return await github.rest.issues.createComment({
      issue_number: context.issue.number,
      owner: context.repo.owner,
      repo: context.repo.repo,
      body,
    })
  }
}

function getCodeBlock(text: string, title: string, lang = 'ts') {
  const regex = new RegExp(
    `## ${title}[\\s\\S]*?\`\`\`${lang}([\\s\\S]*?)\`\`\``,
  )
  const match = text.match(regex)
  if (match && match[1])
    return match[1].toString().trim()
  return null
}

function getCommentRange(text: string, key: string) {
  const regex = new RegExp(`<!--${key}-start-->([\\s\\S]*?)<!--${key}-end-->`)
  const match = text.match(regex)
  if (match && match[1])
    return match[1].toString().trim()
  return null
}

function getTimestampBadge() {
  return `![${new Date().toISOString()}](https://img.shields.io/date/${Math.round(
    +new Date() / 1000,
  )}?color=green&label=)`
}

export default action