import { FormEvent, useEffect, useState } from 'react'
import { Loader2, Save, SettingsIcon } from 'lucide-react'
import toast from 'react-hot-toast'

import { adminAPI } from '../api/admin'
import type { Setting } from '../types'

// SettingsPage replaces the Vue SettingsView's General / Organize /
// Scrape / Adult tabs. The Go backend stores settings as a single
// key/value table; we group the most useful keys client-side and let
// the operator edit them with typed widgets (select / toggle / input).
//
// Any key not in the curated list still works via the AdminPage generic
// key/value editor — this page is the curated UX over the same store.
interface SettingDef {
  key: string
  label: string
  type: 'text' | 'select' | 'toggle' | 'number' | 'textarea'
  hint?: string
  options?: { value: string; label: string }[]
  placeholder?: string
}

interface SettingGroup {
  key: string
  label: string
  description?: string
  items: SettingDef[]
}

const GROUPS: SettingGroup[] = [
  {
    key: 'general',
    label: '常规',
    description: 'TMDb / 转码引擎默认参数',
    items: [
      {
        key: 'tmdb.language',
        label: 'TMDb 元数据语言',
        type: 'select',
        options: [
          { value: 'zh-CN', label: '简体中文' },
          { value: 'zh-TW', label: '繁体中文' },
          { value: 'en-US', label: 'English' },
          { value: 'ja-JP', label: '日本語' },
        ],
      },
      {
        key: 'transcode.enabled',
        label: '启用转码',
        type: 'toggle',
        hint: '关闭后所有视频直连播放',
      },
      {
        key: 'transcode.hw_accel',
        label: '硬件加速',
        type: 'select',
        options: [
          { value: 'auto', label: '自动检测' },
          { value: 'none', label: '软件转码' },
          { value: 'nvenc', label: 'NVIDIA NVENC' },
          { value: 'qsv', label: 'Intel QSV' },
          { value: 'vaapi', label: 'VAAPI (Linux)' },
          { value: 'videotoolbox', label: 'VideoToolbox (macOS)' },
        ],
      },
      {
        key: 'transcode.max_jobs',
        label: '最大并发转码任务',
        type: 'number',
        hint: '建议 1-4',
      },
      {
        key: 'ffmpeg.path',
        label: 'FFmpeg 路径',
        type: 'text',
        placeholder: 'ffmpeg',
      },
      {
        key: 'ffprobe.path',
        label: 'FFprobe 路径',
        type: 'text',
        placeholder: 'ffprobe',
      },
    ],
  },
  {
    key: 'organize',
    label: '整理 & 刮削',
    description: '媒体文件命名 + 自动刮削开关',
    items: [
      {
        key: 'organize.auto',
        label: '入库时自动整理',
        type: 'toggle',
      },
      {
        key: 'organize.movie_format',
        label: '电影命名格式',
        type: 'text',
        hint: '例: {title} ({year})/{title} ({year})',
        placeholder: '{title} ({year})/{title} ({year})',
      },
      {
        key: 'organize.tv_format',
        label: '剧集命名格式',
        type: 'text',
        placeholder: '{title} ({year})/Season {season}/{title} S{season:02}E{episode:02}',
      },
      {
        key: 'organize.anime_format',
        label: '动漫命名格式',
        type: 'text',
        placeholder: '{title}/Season {season}/{title} S{season:02}E{episode:02}',
      },
      {
        key: 'scrape.auto_on_scan',
        label: '扫描后自动刮削',
        type: 'toggle',
      },
      {
        key: 'scrape.providers',
        label: '刮削源优先级',
        type: 'text',
        hint: '逗号分隔: tmdb,bangumi,thetvdb,fanart',
        placeholder: 'tmdb,bangumi,thetvdb,fanart',
      },
      {
        key: 'scrape.language',
        label: '刮削首选语言',
        type: 'text',
        placeholder: 'zh-CN',
      },
    ],
  },
  {
    key: 'adult',
    label: 'Adult / NSFW',
    description: '成人内容隔离开关 (默认隐藏)',
    items: [
      {
        key: 'adult.enabled',
        label: '启用成人内容',
        type: 'toggle',
        hint: '关闭后 NSFW 媒体不会出现在列表中',
      },
      {
        key: 'adult.require_pin',
        label: '访问需要 PIN',
        type: 'toggle',
      },
      {
        key: 'adult.pin',
        label: 'PIN 码',
        type: 'text',
        hint: '4-8 位数字',
      },
    ],
  },
  {
    key: 'qbittorrent',
    label: 'qBittorrent',
    description: '默认下载器配置',
    items: [
      { key: 'qbittorrent.url', label: 'WebUI URL', type: 'text', placeholder: 'http://127.0.0.1:8080' },
      { key: 'qbittorrent.username', label: '用户名', type: 'text' },
      { key: 'qbittorrent.password', label: '密码', type: 'text' },
      { key: 'qbittorrent.savepath', label: '默认保存目录', type: 'text' },
    ],
  },
]

const ALL_KEYS = new Set(GROUPS.flatMap((g) => g.items.map((i) => i.key)))

export function SettingsPage() {
  const [activeGroup, setActiveGroup] = useState(GROUPS[0].key)
  const [values, setValues] = useState<Record<string, string>>({})
  const [dirty, setDirty] = useState<Set<string>>(new Set())
  const [loading, setLoading] = useState(true)
  const [saving, setSaving] = useState(false)

  const refresh = async () => {
    setLoading(true)
    try {
      const all = await adminAPI.listSettings()
      const idx: Record<string, string> = {}
      for (const s of all as Setting[]) {
        if (ALL_KEYS.has(s.key)) idx[s.key] = s.value
      }
      setValues(idx)
      setDirty(new Set())
    } finally {
      setLoading(false)
    }
  }

  useEffect(() => {
    refresh().catch(() => undefined)
  }, [])

  const onChange = (key: string, value: string) => {
    setValues((v) => ({ ...v, [key]: value }))
    setDirty((d) => new Set(d).add(key))
  }

  const onSave = async (e: FormEvent) => {
    e.preventDefault()
    if (dirty.size === 0) return
    setSaving(true)
    try {
      // Backend exposes a single-key updater; loop through dirty keys.
      for (const key of dirty) {
        await adminAPI.updateSetting(key, values[key] ?? '')
      }
      toast.success(`已保存 ${dirty.size} 项配置`)
      setDirty(new Set())
    } catch (err: unknown) {
      const msg =
        (err as { response?: { data?: { error?: string } } })?.response?.data?.error ?? '保存失败'
      toast.error(msg)
    } finally {
      setSaving(false)
    }
  }

  const group = GROUPS.find((g) => g.key === activeGroup)!

  return (
    <div className="space-y-6">
      <div className="flex items-center gap-3">
        <div className="flex h-10 w-10 items-center justify-center rounded-xl bg-slate-400/10 text-slate-300">
          <SettingsIcon size={20} />
        </div>
        <div>
          <h1 className="font-display text-3xl font-bold text-white">系统设置</h1>
          <p className="text-sm text-slate-400">
            按分组编辑 TMDb / 整理 / 刮削 / 下载器等关键配置
          </p>
        </div>
      </div>

      <div className="flex gap-2 overflow-x-auto border-b border-white/10">
        {GROUPS.map((g) => (
          <button
            key={g.key}
            onClick={() => setActiveGroup(g.key)}
            className={
              'border-b-2 px-4 py-2 text-sm whitespace-nowrap transition ' +
              (activeGroup === g.key
                ? 'border-primary-400 text-primary-400'
                : 'border-transparent text-slate-400 hover:text-white')
            }
          >
            {g.label}
          </button>
        ))}
      </div>

      {loading && (
        <div className="flex justify-center py-12 text-slate-400">
          <Loader2 className="animate-spin" />
        </div>
      )}

      {!loading && (
        <form onSubmit={onSave} className="glass-panel space-y-4">
          {group.description && <p className="text-xs text-slate-500">{group.description}</p>}
          {group.items.map((it) => (
            <SettingRow
              key={it.key}
              def={it}
              value={values[it.key] ?? ''}
              onChange={(v) => onChange(it.key, v)}
            />
          ))}
          <div className="flex items-center justify-between pt-2">
            <span className="text-xs text-slate-500">
              {dirty.size > 0 ? `有 ${dirty.size} 项未保存` : '所有更改已保存'}
            </span>
            <button
              type="submit"
              disabled={saving || dirty.size === 0}
              className="neon-button disabled:opacity-50"
            >
              {saving ? <Loader2 size={16} className="animate-spin" /> : <Save size={16} />}
              保存
            </button>
          </div>
        </form>
      )}
    </div>
  )
}

function SettingRow({
  def,
  value,
  onChange,
}: {
  def: SettingDef
  value: string
  onChange: (v: string) => void
}) {
  return (
    <div className="grid items-start gap-2 md:grid-cols-[280px_1fr]">
      <label className="text-sm text-slate-300">
        <div className="font-medium">{def.label}</div>
        {def.hint && <div className="mt-0.5 text-xs text-slate-500">{def.hint}</div>}
        <div className="mt-0.5 font-mono text-[10px] text-slate-600">{def.key}</div>
      </label>
      <div>
        {def.type === 'text' && (
          <input
            className="input-base"
            value={value}
            placeholder={def.placeholder}
            onChange={(e) => onChange(e.target.value)}
          />
        )}
        {def.type === 'number' && (
          <input
            type="number"
            className="input-base"
            value={value}
            placeholder={def.placeholder}
            onChange={(e) => onChange(e.target.value)}
          />
        )}
        {def.type === 'textarea' && (
          <textarea
            rows={3}
            className="input-base font-mono text-xs"
            value={value}
            placeholder={def.placeholder}
            onChange={(e) => onChange(e.target.value)}
          />
        )}
        {def.type === 'select' && (
          <select className="input-base" value={value} onChange={(e) => onChange(e.target.value)}>
            <option value="">(未设置)</option>
            {def.options?.map((o) => (
              <option key={o.value} value={o.value}>
                {o.label}
              </option>
            ))}
          </select>
        )}
        {def.type === 'toggle' && (
          <label className="flex cursor-pointer items-center gap-2">
            <input
              type="checkbox"
              className="h-4 w-4 accent-primary-400"
              checked={value === 'true' || value === '1' || value === 'on'}
              onChange={(e) => onChange(e.target.checked ? 'true' : 'false')}
            />
            <span className="text-sm text-slate-300">{value === 'true' ? '已启用' : '已关闭'}</span>
          </label>
        )}
      </div>
    </div>
  )
}