/**
 * Admin 后台 - 统一设置页(报刊风)
 *
 * 合并原「数据源」「LLM 配置」「系统配置」三页:
 *   1. 数据源 — bzzoiro API Key + Key Ring 状态
 *   2. LLM — 连接配置 + 使用统计 + 专家独立配置
 *   3. 认证 — 修改密码
 *   4. 系统 — 配置查看 + 修改指南
 */

import { useEffect, useState, useCallback } from 'react'
import {
  fetchSettings, updateSetting, clearSetting,
  testLLMConnection, fetchLLMUsageStats, fetchLLMModels,
  fetchKeyRingStatus, resetKeyRingCooldown,
  fetchSchedules, createSchedule, updateSchedule, deleteSchedule, runScheduleNow,
} from '../dal'
import type { ScheduleItem } from '../dal'
import { changePassword, fetchAuthState, UNAUTHORIZED_EVENT } from '../api'
import type { LLMUsageStats, DataSourceSetting } from '../types'
import type { KeyRingStatusResponse } from '../dal'
import { Card, CardBody, CardHeader, Badge, SectionHeader, Alert, Spinner, SkeletonBlock } from '../components'
import SettingRow from '../SettingRow'
import AgentLLMCard from '../AgentLLMCard'

const DATA_SOURCE_KEYS = ['BZZOIRO_KEY', 'BZZOIRO_BASE']
const LLM_KEYS = ['LLM_API_KEY', 'LLM_BASE_URL', 'LLM_MODEL']

export default function SettingsPage() {
  const [allSettings, setAllSettings] = useState<DataSourceSetting[]>([])
  const [settingsLoading, setSettingsLoading] = useState(true)
  const [editingKey, setEditingKey] = useState<string | null>(null)
  const [busyKey, setBusyKey] = useState<string | null>(null)
  const [rowNotice, setRowNotice] = useState<{ key: string; ok: boolean; text: string } | null>(null)

  // LLM
  const [llmStats, setLlmStats] = useState<LLMUsageStats | null>(null)
  const [llmLoading, setLlmLoading] = useState(true)
  const [testing, setTesting] = useState(false)
  const [testResult, setTestResult] = useState<{ success: boolean; message: string } | null>(null)

  // Key Ring
  const [keyRing, setKeyRing] = useState<KeyRingStatusResponse | null>(null)
  const [ringLoading, setRingLoading] = useState(false)

  // 密码
  const [passwordOrigin, setPasswordOrigin] = useState<'db' | 'env' | 'none' | null>(null)
  const [currentPwd, setCurrentPwd] = useState('')
  const [newPwd, setNewPwd] = useState('')
  const [confirmPwd, setConfirmPwd] = useState('')
  const [pwdBusy, setPwdBusy] = useState(false)
  const [pwdNotice, setPwdNotice] = useState<{ ok: boolean; text: string } | null>(null)

  // 定时任务
  const [schedules, setSchedules] = useState<ScheduleItem[]>([])
  const [schedulesLoading, setSchedulesLoading] = useState(true)
  const [scheduleNotice, setScheduleNotice] = useState<{ ok: boolean; text: string } | null>(null)
  const [scheduleBusyId, setScheduleBusyId] = useState<string | null>(null)

  // ── 数据加载 ──
  const loadSettings = useCallback(async () => {
    setSettingsLoading(true)
    try {
      const all = await fetchSettings()
      setAllSettings(all)
    } catch {
      setAllSettings([])
    } finally {
      setSettingsLoading(false)
    }
  }, [])

  const loadLlmStats = useCallback(async () => {
    setLlmLoading(true)
    try {
      setLlmStats(await fetchLLMUsageStats())
    } catch {
      setLlmStats(null)
    } finally {
      setLlmLoading(false)
    }
  }, [])

  const loadKeyRing = useCallback(async () => {
    setRingLoading(true)
    try {
      setKeyRing(await fetchKeyRingStatus())
    } catch {
      setKeyRing(null)
    } finally {
      setRingLoading(false)
    }
  }, [])

  useEffect(() => {
    loadSettings()
    loadLlmStats()
    loadKeyRing()
    fetchAuthState().then(s => setPasswordOrigin(s.password_origin ?? null)).catch(() => {})
    fetchSchedules().then(setSchedules).catch(() => []).finally(() => setSchedulesLoading(false))
  }, [loadSettings, loadLlmStats, loadKeyRing])

  const dataSourceSettings = allSettings.filter(s => DATA_SOURCE_KEYS.includes(s.key))
  const llmSettings = allSettings.filter(s => LLM_KEYS.includes(s.key))

  // ── 操作 ──
  const handleSave = async (key: string, value: string) => {
    setBusyKey(key)
    setRowNotice(null)
    try {
      await updateSetting(key, value)
      setRowNotice({ key, ok: true, text: '已保存,立即生效' })
      setEditingKey(null)
      await loadSettings()
      if (key === 'BZZOIRO_KEY') await loadKeyRing()
    } catch (err) {
      setRowNotice({ key, ok: false, text: err instanceof Error ? err.message.split('\n')[0] : '保存失败' })
    } finally {
      setBusyKey(null)
    }
  }

  const handleClear = async (key: string) => {
    setBusyKey(key)
    setRowNotice(null)
    try {
      await clearSetting(key)
      setRowNotice({ key, ok: true, text: '已清除数据库覆盖,回落 .env 默认值' })
      await loadSettings()
    } catch (err) {
      setRowNotice({ key, ok: false, text: err instanceof Error ? err.message.split('\n')[0] : '清除失败' })
    } finally {
      setBusyKey(null)
    }
  }

  // ── 定时任务操作 ──
  const handleToggleSchedule = async (s: ScheduleItem) => {
    setScheduleBusyId(s.id)
    setScheduleNotice(null)
    try {
      await updateSchedule(s.id, { enabled: !s.enabled })
      setScheduleNotice({ ok: true, text: `已${!s.enabled ? '启用' : '禁用'}任务「${s.id}」` })
      setSchedules(prev => prev.map(x => x.id === s.id ? { ...x, enabled: !x.enabled } : x))
    } catch {
      setScheduleNotice({ ok: false, text: '操作失败' })
    } finally {
      setScheduleBusyId(null)
    }
  }

  const handleRunSchedule = async (s: ScheduleItem) => {
    setScheduleBusyId(s.id)
    setScheduleNotice(null)
    try {
      await runScheduleNow(s.id)
      setScheduleNotice({ ok: true, text: `任务「${s.id}」已启动,请在日志页查看进度` })
    } catch {
      setScheduleNotice({ ok: false, text: '启动失败' })
    } finally {
      setScheduleBusyId(null)
    }
  }

  const handleDeleteSchedule = async (s: ScheduleItem) => {
    setScheduleBusyId(s.id)
    setScheduleNotice(null)
    try {
      await deleteSchedule(s.id)
      setScheduleNotice({ ok: true, text: `已删除任务「${s.id}」` })
      setSchedules(prev => prev.filter(x => x.id !== s.id))
    } catch {
      setScheduleNotice({ ok: false, text: '删除失败' })
    } finally {
      setScheduleBusyId(null)
    }
  }

  const detectLLMModels = useCallback(async (): Promise<string[]> => {
    const r = await fetchLLMModels()
    if (!r.ok) throw new Error(r.detail)
    return r.models
  }, [])

  const handleTest = async () => {
    setTesting(true)
    setTestResult(null)
    try {
      await testLLMConnection()
      setTestResult({ success: true, message: 'LLM 连接测试成功' })
    } catch (err: unknown) {
      setTestResult({ success: false, message: err instanceof Error ? err.message : 'LLM 连接测试失败' })
    } finally {
      setTesting(false)
    }
  }

  const handleResetCooldown = async () => {
    if (!window.confirm('确定重置所有 key 的冷却状态?这可能使被限流的 key 立即恢复请求。')) return
    try {
      const res = await resetKeyRingCooldown()
      setKeyRing(res.stats)
      setRowNotice({ key: "__ring", ok: true, text: res.message })
    } catch (err) {
      setRowNotice({ key: "__ring", ok: false, text: err instanceof Error ? err.message.split('\n')[0] : '重置失败' })
    }
  }

  const handleChangePassword = async (e: React.FormEvent) => {
    e.preventDefault()
    setPwdNotice(null)
    if (newPwd !== confirmPwd) {
      setPwdNotice({ ok: false, text: '两次输入的新密码不一致' })
      return
    }
    setPwdBusy(true)
    try {
      const res = await changePassword(currentPwd, newPwd)
      setPwdNotice({ ok: true, text: res.message })
      setTimeout(() => window.dispatchEvent(new CustomEvent(UNAUTHORIZED_EVENT)), 1500)
    } catch (err) {
      setPwdNotice({ ok: false, text: err instanceof Error ? err.message.split('\n')[0] : '修改失败' })
    } finally {
      setPwdBusy(false)
    }
  }

  return (
    <div className="space-y-8">
      <SectionHeader
        title="系统设置"
        description="数据源、LLM、认证等全部配置。保存到数据库并立即生效,优先于 .env。"
      />

      {/* ── 1. 数据源 ── */}
      <section>
        <h2 className="section-head mb-3">数据源</h2>
        <div className="grid gap-6 lg:grid-cols-2">
          <Card>
            <CardHeader
              title="Bzzoiro API"
              description="赛程 / 比分 / 积分榜 / 比赛统计的唯一数据源"
              action={<button onClick={loadSettings} disabled={settingsLoading} className="btn btn-sm">{settingsLoading ? <><Spinner /> 加载中</> : '刷新'}</button>}
            />
            <CardBody>
              {settingsLoading ? (
                <div className="space-3">{dataSourceSettings.map((_, i) => <SkeletonBlock key={i} className="h-9 w-full" />)}</div>
              ) : (
                dataSourceSettings.map(setting => (
                  <SettingRow
                    key={setting.key}
                    setting={setting}
                    editing={editingKey === setting.key}
                    busy={busyKey === setting.key}
                    onEdit={() => { setEditingKey(setting.key); setRowNotice(null) }}
                    onCancel={() => setEditingKey(null)}
                    onSave={v => handleSave(setting.key, v)}
                    onClear={() => handleClear(setting.key)}
                  />
                ))
              )}
              {rowNotice && !rowNotice.key.startsWith('__') && dataSourceSettings.some(s => s.key === rowNotice.key) && (
                <div className="mt-3"><Alert kind={rowNotice.ok ? 'ok' : 'error'} title={rowNotice.text} /></div>
              )}
            </CardBody>
          </Card>

          {/* Key Ring */}
          <Card>
            <CardHeader
              title="API Key 轮换环"
              description={keyRing?.has_multiple ? `已配置 ${keyRing.total} 个 key,遇限流自动切换` : '当前仅 1 个 key,无法轮换'}
              action={<button onClick={handleResetCooldown} disabled={ringLoading} className="btn-sm btn-outline">重置冷却</button>}
            />
            <CardBody>
              {keyRing && keyRing.total > 0 ? (
                <div className="space-y-2">
                  {keyRing.keys.map((k, i) => {
                    const isBlocked = k.blocked_remaining > 0
                    return (
                      <div key={i} className={`flex items-center justify-between gap-3 border-b border-ink-100 py-2 last:border-b-0 ${isBlocked ? 'opacity-70' : ''}`}>
                        <div className="flex items-center gap-2">
                          <span className={`inline-block h-2 w-2 rounded-full ${isBlocked ? 'bg-amber-500' : 'bg-emerald-500'}`} />
                          <span className="font-mono text-xs text-ink-700">{k.masked}</span>
                          {i === keyRing.active_index && <span className="rounded bg-ink-900 px-1.5 py-0.5 text-2xs text-paper-500">当前</span>}
                        </div>
                        <span className={`text-2xs tabular-nums ${isBlocked ? 'text-amber-600' : 'text-ink-400'}`}>
                          {isBlocked ? `冷却中 ${k.blocked_remaining.toFixed(0)}s` : '可用'}
                        </span>
                      </div>
                    )
                  })}
                </div>
              ) : (
                <p className="text-xs text-ink-400">暂无 key 配置</p>
              )}
            </CardBody>
          </Card>
        </div>
      </section>

      {/* ── 2. LLM ── */}
      <section>
        <h2 className="section-head mb-3">大语言模型</h2>
        <div className="grid gap-6 lg:grid-cols-2">
          <Card>
            <CardHeader
              title="连接配置"
              description="OpenAI 兼容接口(DeepSeek / 智谱 / 通义等)"
              action={<button onClick={loadSettings} disabled={settingsLoading} className="btn btn-sm">{settingsLoading ? <><Spinner /> 加载中</> : '刷新'}</button>}
            />
            <CardBody>
              {settingsLoading ? (
                <div className="space-y-3">{llmSettings.map((_, i) => <SkeletonBlock key={i} className="h-9 w-full" />)}</div>
              ) : (
                llmSettings.map(setting => (
                  <SettingRow
                    key={setting.key}
                    setting={setting}
                    editing={editingKey === setting.key}
                    busy={busyKey === setting.key}
                    onEdit={() => { setEditingKey(setting.key); setRowNotice(null) }}
                    onCancel={() => setEditingKey(null)}
                    onSave={v => handleSave(setting.key, v)}
                    onClear={() => handleClear(setting.key)}
                    detectModels={setting.key === 'LLM_MODEL' ? detectLLMModels : undefined}
                  />
                ))
              )}
              {rowNotice && !rowNotice.key.startsWith('__') && llmSettings.some(s => s.key === rowNotice.key) && (
                <div className="mt-3"><Alert kind={rowNotice.ok ? 'ok' : 'error'} title={rowNotice.text} /></div>
              )}
              {testResult && (
                <div className="mt-4">
                  <Alert kind={testResult.success ? 'ok' : 'error'} title={testResult.success ? '连接正常' : '连接失败'} message={testResult.success ? undefined : testResult.message} />
                </div>
              )}
              <button onClick={handleTest} disabled={testing} className="btn btn-sm mt-4 w-full">
                {testing ? <><Spinner /> 测试中</> : '测试 LLM 连接'}
              </button>
              <p className="mt-2 text-center text-2xs text-ink-400">测试会真实调用一次 LLM 预测,产生费用。</p>
            </CardBody>
          </Card>

          <Card>
            <CardHeader title="使用统计" description="从最近预测记录聚合" action={<button onClick={loadLlmStats} disabled={llmLoading} className="btn btn-sm">{llmLoading ? <><Spinner /> 加载中</> : '刷新'}</button>} />
            <CardBody>
              {llmLoading ? (
                <div className="space-y-3"><SkeletonBlock className="h-16 w-full" /><SkeletonBlock className="h-16 w-full" /></div>
              ) : llmStats ? (
                <div className="grid grid-cols-3 gap-4">
                  <div className="border-t-2 border-ink-900 pt-3 text-center">
                    <div className="font-serif text-2xl font-bold tabular-nums text-ink-900">{llmStats.total_predictions}</div>
                    <div className="mt-1 text-2xs text-ink-400">总预测数</div>
                  </div>
                  <div className="border-t-2 border-ink-900 pt-3 text-center">
                    <div className="font-serif text-2xl font-bold tabular-nums text-ink-900">{llmStats.avg_latency_ms > 0 ? `${(llmStats.avg_latency_ms / 1000).toFixed(1)}s` : '—'}</div>
                    <div className="mt-1 text-2xs text-ink-400">平均延迟</div>
                  </div>
                  <div className="border-t-2 border-press pt-3 text-center">
                    <div className="font-serif text-2xl font-bold tabular-nums text-press">{llmStats.success_rate.toFixed(0)}%</div>
                    <div className="mt-1 text-2xs text-ink-400">有效率</div>
                  </div>
                </div>
              ) : (
                <p className="py-6 text-center text-xs text-ink-400">暂无使用统计数据</p>
              )}
            </CardBody>
          </Card>
        </div>
        <div className="mt-6">
          <AgentLLMCard />
        </div>
      </section>

      {/* ── 3. 认证 ── */}
      <section>
        <h2 className="section-head mb-3">登录认证</h2>
        <Card>
          <CardHeader title="修改密码" description="密码即会话签名密钥,修改后所有已登录会话失效,需重新登录" />
          <CardBody>
            {passwordOrigin && (
              <p className="mb-3 flex items-center gap-2 text-2xs text-ink-500">
                当前密码来源:
                {passwordOrigin === 'db' ? <Badge status="success">数据库(scrypt 哈希)</Badge>
                  : passwordOrigin === 'env' ? <Badge status="info">.env 初始值</Badge>
                  : <Badge status="error">未配置</Badge>}
              </p>
            )}
            <form onSubmit={handleChangePassword} className="space-y-3">
              <div className="grid gap-3 sm:grid-cols-3">
                <div>
                  <label className="mb-1 block text-2xs text-ink-500">当前密码</label>
                  <input type="password" value={currentPwd} onChange={e => setCurrentPwd(e.target.value)} autoComplete="current-password" className="field w-full" />
                </div>
                <div>
                  <label className="mb-1 block text-2xs text-ink-500">新密码(至少 8 位)</label>
                  <input type="password" value={newPwd} onChange={e => setNewPwd(e.target.value)} autoComplete="new-password" className="field w-full" />
                </div>
                <div>
                  <label className="mb-1 block text-2xs text-ink-500">确认新密码</label>
                  <input type="password" value={confirmPwd} onChange={e => setConfirmPwd(e.target.value)} autoComplete="new-password" className="field w-full" />
                </div>
              </div>
              {pwdNotice && <Alert kind={pwdNotice.ok ? 'ok' : 'error'} title={pwdNotice.text} />}
              <div className="flex items-center justify-between gap-2">
                <p className="text-2xs text-ink-400">修改成功后会自动退出登录。</p>
                <button type="submit" disabled={pwdBusy || !currentPwd || !newPwd || !confirmPwd} className="btn btn-solid btn-sm flex-shrink-0">
                  {pwdBusy ? <><Spinner /> 修改中</> : '修改密码'}
                </button>
              </div>
            </form>
          </CardBody>
        </Card>
      </section>

      {/* ── 4. 定时任务 ── */}
      <section>
        <h2 className="section-head mb-3">定时任务</h2>
        <Card>
          <CardHeader
            title="采集调度"
            description="配置 cron 表达式定时触发采集任务"
            action={
              <button
                onClick={() => {
                  createSchedule({ id: `schedule-${Date.now()}`, task: 'events', cron: '0 8 * * *', leagues: undefined, enabled: false })
                    .then(() => fetchSchedules().then(setSchedules))
                }}
                className="btn btn-sm"
              >
                + 新建
              </button>
            }
          />
          <CardBody>
            {scheduleNotice && (
              <div className="mb-3">
                <Alert kind={scheduleNotice.ok ? 'ok' : 'error'} title={scheduleNotice.text} onClose={() => setScheduleNotice(null)} />
              </div>
            )}
            {schedulesLoading ? (
              <SkeletonBlock className="h-10 w-full" />
            ) : schedules.length === 0 ? (
              <p className="py-6 text-center text-xs text-ink-400">暂无定时任务,点击右上角「+ 新建」创建</p>
            ) : (
              <div className="space-y-2">
                {schedules.map(s => (
                  <div key={s.id} className="flex flex-col gap-2 border-b border-ink-100 py-3 last:border-b-0 sm:flex-row sm:items-center sm:justify-between">
                    <div className="flex-1 space-y-1">
                      <div className="flex items-center gap-2">
                        <span className={`inline-block h-2 w-2 rounded-full ${s.enabled ? 'bg-emerald-500' : 'bg-ink-300'}`} />
                        <span className="text-xs font-medium text-ink-800">{s.id}</span>
                        <Badge status={s.enabled ? 'success' : 'muted'}>{s.task}</Badge>
                      </div>
                      <p className="font-mono text-2xs text-ink-500">{s.cron}</p>
                      {s.last_run_at && (
                        <p className="text-2xs text-ink-400">
                          上次: {new Date(s.last_run_at).toLocaleString('zh-CN', { hour12: false })}
                          {s.last_status === 'success' ? ' ✓' : s.last_status === 'failed' ? ' ✗' : ''}
                        </p>
                      )}
                    </div>
                    <div className="flex items-center gap-2">
                      <button
                        onClick={() => handleRunSchedule(s)}
                        disabled={scheduleBusyId === s.id}
                        className="btn btn-sm"
                      >
                        {scheduleBusyId === s.id ? <Spinner /> : '立即执行'}
                      </button>
                      <button
                        onClick={() => handleToggleSchedule(s)}
                        disabled={scheduleBusyId === s.id}
                        className={`btn btn-sm ${s.enabled ? '' : 'btn-solid'}`}
                      >
                        {scheduleBusyId === s.id ? <Spinner /> : (s.enabled ? '禁用' : '启用')}
                      </button>
                      <button
                        onClick={() => handleDeleteSchedule(s)}
                        disabled={scheduleBusyId === s.id}
                        className="btn btn-sm btn-danger"
                      >
                        {scheduleBusyId === s.id ? <Spinner /> : '删除'}
                      </button>
                    </div>
                  </div>
                ))}
              </div>
            )}
          </CardBody>
        </Card>
      </section>
    </div>
  )
}