import type { Engine, Register } from 'claude-code'

import { CHARACTERS, applyOverrides, findCharacter, personaSection } from './characters'
import type { Axes } from './characters'
import { layout, meter, parseFields, remainColor, SEPARATOR, usedColor } from './statusline'
import type { Segment } from './statusline'
import { CACHE_MS, addEntry, commandName, commitMessage, pageName, parseCatalog, parseWriteArgs, renderHome, renderPage, renderSidebar, teaToken, wikiUrlFromRemote } from './wiki'
import type { Entry } from './wiki'

const ACTIVE_KEY = 'active'
const OFF_COMMAND = 'anima-off'
const WIKI_COMMAND = 'anima-wiki'
const SYNCED_KEY = 'wikiSyncedAt'
const NEED_ACTIVE = '請先啟動角色（/jsc-anima:{作品代號}-{角色代號}）再使用這個工具。'

const AXIS_OPTION: Record<keyof Axes, string> = {
  gentle: 'axisGentle',
  tsundere: 'axisTsundere',
  lively: 'axisLively',
  formal: 'axisFormal',
  talkative: 'axisTalkative',
  humor: 'axisHumor',
  proactive: 'axisProactive',
  expressive: 'axisExpressive',
}

const SYS_SCRIPT =
  'a=$(awk \'{print $1}\' /proc/loadavg); n=$(nproc); ' +
  'echo "$a $n"; free | awk \'/Mem:/{printf "%d\\n", $3*100/$2}\'; df / | awk \'NR==2{gsub("%","",$5); print $5}\''

const resetText = (iso: string | undefined, long: boolean): string => {
  if (!iso) return ''
  const d = new Date(iso)
  if (Number.isNaN(d.getTime())) return ''
  const p = (n: number) => String(n).padStart(2, '0')
  return long ? ` ${d.getMonth() + 1}/${d.getDate()}` : ` ${p(d.getHours())}:${p(d.getMinutes())}`
}

const fmtTokens = (n: number): string => (n >= 1000 ? `${Math.round(n / 1000)}k` : String(n))

type Sys = { at: number; cpu: number; ram: number; dsk: number }

async function readSys($: Engine, holder: { sys?: Sys }, refreshMs: number): Promise<Sys | undefined> {
  const now = await $.clock.now()
  if (holder.sys && now - holder.sys.at < refreshMs) return holder.sys
  try {
    const r = await $.process.run(['sh', '-c', SYS_SCRIPT], { timeoutMs: 3000 })
    const [l1, l2, l3] = String(r.stdout).trim().split('\n')
    const [load, cores] = (l1 ?? '').split(' ').map(Number)
    holder.sys = {
      at: now,
      cpu: Math.min(100, Math.round(((load || 0) / (cores || 1)) * 100)),
      ram: Number(l2) || 0,
      dsk: Number(l3) || 0,
    }
  } catch {
    holder.sys = undefined
  }
  return holder.sys
}

type WikiCfg = { url: string; cacheDir: string }
type Wiki = { dir: string; url: string; auth: string[] }

async function wikiCtx($: Engine, cfg: WikiCfg): Promise<Wiki | undefined> {
  let url = cfg.url
  if (!url) {
    const cwd = await $.session.cwd().catch(() => '')
    const r = await $.process.run(['git', 'remote', 'get-url', 'origin'], { cwd: cwd || undefined, timeoutMs: 3000 }).catch(() => undefined)
    url = (r && r.exitCode === 0 && wikiUrlFromRemote(String(r.stdout))) || ''
  }
  if (!url) return undefined
  const home = (await $.env.get('HOME')) ?? ''
  const dir = cfg.cacheDir || `${home}/.cache/jsc-anima/wiki`
  // 認證：優先 tea 登入，其次 GITEA_TOKEN；token 只放在指令參數，不寫入任何檔案。
  let token: string | undefined
  try {
    token = teaToken(await $.fs.read(`${home}/.config/tea/config.yml`), new URL(url).host)
  } catch {}
  token ??= (await $.env.get('GITEA_TOKEN')) || undefined
  return { dir, url, auth: token ? ['-c', `http.extraHeader=Authorization: token ${token}`] : [] }
}

async function git($: Engine, w: Wiki, args: string[], inDir = true) {
  const r = await $.process.run(['git', ...w.auth, ...(inDir ? ['-C', w.dir] : []), ...args], { timeoutMs: 60000 }).catch(() => undefined)
  return r && r.exitCode === 0 ? r : undefined
}

// 本機只做 10 分鐘快取；離線時沿用已有的快取。
async function sync($: Engine, w: Wiki, force: boolean): Promise<'fresh' | 'cached' | 'none'> {
  const cloned = await $.fs.exists(`${w.dir}/.git`).catch(() => false)
  const now = await $.clock.now()
  const last = Number((await $.store.get(SYNCED_KEY)) ?? 0)
  if (cloned && !force && now - last < CACHE_MS) return 'fresh'
  const ok = cloned ? await git($, w, ['pull', '--ff-only']) : await git($, w, ['clone', w.url, w.dir], false)
  if (ok) {
    await $.store.set(SYNCED_KEY, now)
    return 'fresh'
  }
  return cloned ? 'cached' : 'none'
}

async function readCatalog($: Engine, w: Wiki): Promise<Entry[]> {
  return parseCatalog(await $.fs.read(`${w.dir}/Home.md`).catch(() => ''))
}

async function registerEntry($: Engine, known: Set<string>, e: Entry) {
  const name = commandName(e)
  if (known.has(name)) return
  known.add(name)
  await $.command.register({ name, description: `讀取知識庫：${e.domain}／${e.topic}` })
}

// 工具三的指令只在啟動角色後註冊，依 wiki 目錄動態註冊。
async function registerWikiTools($: Engine, cfg: WikiCfg, known: Set<string>) {
  if (!known.has(WIKI_COMMAND)) {
    known.add(WIKI_COMMAND)
    await $.command.register({ name: WIKI_COMMAND, description: '整理資料寫入 wiki 知識庫', argumentHint: '<領域> <主題> [出處]（下一行起為內容）' })
  }
  try {
    const w = await wikiCtx($, cfg)
    if (!w) return
    await sync($, w, false)
    for (const e of await readCatalog($, w)) await registerEntry($, known, e)
  } catch {}
}

async function writeWiki($: Engine, cfg: WikiCfg, known: Set<string>, args: string): Promise<string> {
  const parsed = parseWriteArgs(args)
  if (!parsed) return '用法：/jsc-anima:anima-wiki <領域> <主題> [出處]，下一行起寫內容。領域與主題只能用英數與底線（會成為指令名稱）。'
  const w = await wikiCtx($, cfg)
  if (!w) return '找不到 wiki 位址：請在 /config 設定 wikiUrl，或在 Gitea 專案目錄中使用。'
  if ((await sync($, w, true)) === 'none') return '無法連線到 wiki，且本機沒有快取，未寫入。'
  const { entry, source, body } = parsed
  const file = `${w.dir}/${pageName(entry)}.md`
  const existed = await $.fs.exists(file).catch(() => false)
  const catalog = addEntry(await readCatalog($, w), entry)
  await $.fs.write(file, renderPage(entry, body, source))
  await $.fs.write(`${w.dir}/Home.md`, renderHome(catalog))
  await $.fs.write(`${w.dir}/_Sidebar.md`, renderSidebar(catalog))
  if (!(await git($, w, ['add', '-A'])) || !(await git($, w, ['commit', '-m', commitMessage(entry, existed)]))) {
    return '寫入失敗：無法建立 commit。'
  }
  if (!(await git($, w, ['push']))) {
    await git($, w, ['reset', '--hard', 'HEAD~1'])
    return '推送 wiki 失敗，已還原本機變更，請稍後再試。'
  }
  await $.store.set(SYNCED_KEY, await $.clock.now())
  await registerEntry($, known, entry)
  return `已${existed ? '更新' : '新增'}知識「${entry.domain}／${entry.topic}」，指令：/jsc-anima:${commandName(entry)}`
}

async function readWiki($: Engine, cfg: WikiCfg, name: string): Promise<string | undefined> {
  const w = await wikiCtx($, cfg)
  if (!w) return undefined
  await sync($, w, false)
  const e = (await readCatalog($, w)).find(x => commandName(x) === name)
  if (!e) return undefined
  return await $.fs.read(`${w.dir}/${pageName(e)}.md`).catch(() => undefined)
}

export const register: Register = (on, options) => {
  const opt = options as Record<string, unknown>
  const flag = (k: string, d: boolean) => (typeof opt[k] === 'boolean' ? (opt[k] as boolean) : d)
  const num = (k: string, d: number) => (typeof opt[k] === 'number' ? (opt[k] as number) : d)
  const str = (k: string, d: string) => (typeof opt[k] === 'string' ? (opt[k] as string) : d)

  const isEnabled = flag('enabled', true)
  let active: string | undefined
  const holder: { sys?: Sys } = {}
  const wikiCommands = new Set<string>()
  const wikiCfg = (): WikiCfg => ({ url: str('wikiUrl', ''), cacheDir: str('wikiCacheDir', '') })

  const overrides = (): Partial<Axes> => {
    const out: Partial<Axes> = {}
    for (const k of Object.keys(AXIS_OPTION) as (keyof Axes)[]) {
      const v = num(AXIS_OPTION[k], -1)
      if (v >= 0) out[k] = v
    }
    return out
  }

  on('session.start', async ($, e, next) => {
    if (isEnabled) {
      for (const c of CHARACTERS) {
        await $.command.register({ name: c.slug, description: `啟動《${c.work}》的${c.name}` })
      }
      await $.command.register({ name: OFF_COMMAND, description: '離開角色，回到一般的 Claude Code' })
      const saved = await $.store.get(ACTIVE_KEY)
      active = flag('persist', true) && typeof saved === 'string' && findCharacter(saved) ? saved : undefined
      if (active) await registerWikiTools($, wikiCfg(), wikiCommands)
    }
    return next(e)
  })

  on('command.run', async ($, e, next) => {
    if (!isEnabled) return next(e)
    if (e.command === OFF_COMMAND) {
      active = undefined
      await $.store.delete(ACTIVE_KEY)
      return { text: '已離開角色，回到一般模式。' }
    }
    const c = findCharacter(e.command)
    if (!c) {
      if (!wikiCommands.has(e.command)) return next(e)
      if (!findCharacter(active)) return { text: NEED_ACTIVE }
      if (e.command === WIKI_COMMAND) return { text: await writeWiki($, wikiCfg(), wikiCommands, String(e.args ?? '')) }
      const page = await readWiki($, wikiCfg(), e.command)
      return { text: page ?? `找不到知識「${e.command}」。` }
    }
    active = c.slug
    await $.store.set(ACTIVE_KEY, c.slug)
    await registerWikiTools($, wikiCfg(), wikiCommands)
    return { text: `已啟動：${c.name}（${c.work}）。用 /jsc-anima:${OFF_COMMAND} 離開。` }
  })

  on('prompt.compose', async ($, e, next) => {
    const res = await next(e)
    const c = isEnabled ? findCharacter(active) : undefined
    if (!c) return res
    const text = personaSection(c, applyOverrides(c.axes, overrides()))
    return {
      ...res,
      sections: [...res.sections.filter(s => s.id !== 'jsc-anima:persona'), { id: 'jsc-anima:persona', text, scope: 'session' as const }],
    }
  })

  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
    const c = isEnabled ? findCharacter(active) : undefined
    if (!c || !flag('statusbar', true) || e.props.hasSurvey) return next(e)

    const warn = num('warnAt', 60)
    const danger = num('dangerAt', 85)
    const style = str('barStyle', 'block') === 'dot' ? 'dot' : 'block'
    const usage = await $.session.usage().catch(() => undefined)
    const cwd = await $.session.cwd().catch(() => '')
    const branch = await $.process
      .run(['git', 'branch', '--show-current'], { cwd: cwd || undefined, timeoutMs: 2000 })
      .then(r => String(r.stdout).trim())
      .catch(() => '')
    const model = await $.session.model().catch(() => '')

    const quota = (kind: string, label: string, long: boolean): Segment['parts'] | undefined => {
      const rl = usage?.rateLimits.find(r => r.kind === kind)
      if (!rl) return undefined
      const remain = Math.max(0, 100 - rl.percentUsed)
      return meter(label, remain, remainColor(remain, warn, danger), style, resetText(rl.resetsAt, long))
    }

    const builders: Record<string, () => Promise<Segment['parts'] | undefined> | Segment['parts'] | undefined> = {
      character: () => [{ text: c.name, color: 'cyan' }],
      model: () => (model ? [{ text: model }] : undefined),
      dir: () => (cwd ? [{ text: cwd.split('/').filter(Boolean).pop() ?? '/' }] : undefined),
      branch: () => (branch ? [{ text: `⎇ ${branch}` }] : undefined),
      '5h': () => quota('five_hour', '5h', false),
      '7d': () => quota('seven_day', '7d', true),
      ctx: () => {
        const cx = usage?.context
        if (!cx || cx.percent === undefined) return undefined
        return meter('ctx', cx.percent, usedColor(cx.percent, warn, danger), style, ` ${fmtTokens(cx.tokens ?? 0)}/${fmtTokens(cx.window)}`)
      },
      sys: async () => {
        const s = await readSys($, holder, num('refreshSec', 10) * 1000)
        if (!s) return undefined
        return [
          { text: 'CPU ' }, { text: `${s.cpu}%`, color: usedColor(s.cpu, warn, danger) },
          { text: ' RAM ' }, { text: `${s.ram}%`, color: usedColor(s.ram, warn, danger) },
          { text: ' DSK ' }, { text: `${s.dsk}%`, color: usedColor(s.dsk, warn, danger) },
        ]
      },
    }

    const segments: Segment[] = []
    for (const id of parseFields(str('fields', ''))) {
      const parts = await builders[id]?.()
      if (parts) segments.push({ id, parts })
    }

    const shown = layout(segments, e.props.bodyColumns)
    const { Box, Text } = $.ui.resolve(e)
    return (
      <Box flexDirection="column">
        <Text> </Text>
        <Text wrap="truncate-end">
          {shown.map((s, i) => (
            <Text key={s.id}>
              {i > 0 ? <Text dimColor>{SEPARATOR}</Text> : null}
              {s.parts.map((p, j) => (
                <Text key={j} color={p.color}>{p.text}</Text>
              ))}
            </Text>
          ))}
        </Text>
        <Text> </Text>
      </Box>
    )
  })
}