import type { Register } from 'claude-code'

import { fitCompanion } from './companion/band'
import { createCompanion } from './companion/core'
import { engineFs } from './companion/engine-fs'

let companion: ReturnType<typeof createCompanion> | undefined
let replying = false
let typedAt = 0
let timer: { cancel(): void } | undefined

const TICK_MS = 60_000
const TYPING_MS = 5_000

export const register: Register = on => {
  on('session.start', async ($, e, next) => {
    await $.command.register({
      name: 'companion',
      description: '角色陪伴控制：狀態、切換角色、關閉、使用者設定',
      argumentHint: 'status | switch <角色> | off | setup',
    })
    const home = await $.env.get('HOME')
    companion = createCompanion({ fs: engineFs({ read: p => $.fs.read(p), write: (p, t) => $.fs.write(p, t), list: p => $.fs.list(p) }), clock: { now: Date.now }, root: `${home ?? ''}/.companion` })
    const first = await companion.ensureActivated()
    if (first.first) $.ui.toast(`已啟用 ${first.name}。用 /companion off 可關閉`)

    // 定時檢查 toast 類關心（到期待辦、作息）；失敗不影響主流程
    timer?.cancel()
    timer = $.clock.every(TICK_MS, () => {
      companion
        ?.tick({ replying, typing: Date.now() - typedAt < TYPING_MS })
        .then(cares => cares.forEach(c => $.ui.toast(c.text)))
        .catch(() => {})
    })

    return next(e)
  })

  on('command.run', { command: 'companion' }, async ($, e) => ({
    text: companion ? await companion.command(e.args) : '尚未就緒。',
  }))

  // 角色卡附加在 system prompt 尾端（session 區段），語氣才會進到模型
  on('prompt.compose', async ($, e, next) => {
    const result = await next(e)
    const text = await companion?.prompt()
    if (!text) return result
    return { sections: [...result.sections, { id: 'companion:persona', text, scope: 'session' as const }] }
  })

  on('prompt.submit', async ($, e, next) => {
    // 更新心情失敗不能擋下使用者的提示
    const care = (await companion?.onPrompt(e.text).catch(() => [] as string[])) ?? []
    return next(care.length ? { ...e, context: [...(e.context ?? []), ...care] } : e)
  })

  on('prompt.edit', async ($, e, next) => {
    typedAt = Date.now()
    return next(e)
  })

  on('turn.start', async ($, e, next) => {
    replying = true
    return next(e)
  })

  on('turn.complete', async ($, e, next) => {
    replying = false
    return next(e)
  })

  // 連續工具失敗會觸發關心，並影響心情
  on('tool.call', async ($, e, next) => {
    const r = await next(e)
    companion?.onToolResult(!r.isError).catch(() => {})
    return r
  })

  on('session.end', async ($, e, next) => {
    timer?.cancel()
    timer = undefined
    await companion?.end().catch(() => {})
    return next(e)
  })

  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
    const rest = await next(e)
    const view = await companion?.view()
    if (e.props.hasSurvey || !view) return rest

    const line = fitCompanion(view, e.props.bodyColumns)
    const { Box, Text } = $.ui.resolve(e)

    return (
      <Box flexDirection="column">
        {rest}
        <Box marginTop={1}>
          <Text wrap="truncate">
            {line.map(s => (
              <Text color={s.color} dimColor={s.dim} bold={s.bold}>
                {s.text}
              </Text>
            ))}
          </Text>
        </Box>
      </Box>
    )
  })
}