/**
 * Admin 后台 - 专家与终裁独立 LLM 配置卡片
 *
 * 每个角色(5 专家 + 终裁)可独立覆盖 模型 / 接口地址 / API Key;
 * 留空字段不改动,「恢复继承」删除该角色全部覆盖。
 */

import { useCallback, useEffect, useState } from 'react'
import { fetchLLMAgents, updateSetting, clearSetting } from './dal'
import type { LLMAgentConfig } from './types'
import { Card, CardBody, CardHeader, Badge, Alert, Spinner, SkeletonBlock } from './components'

type FieldKey = 'model' | 'base_url' | 'api_key'

const FIELD_META: { key: FieldKey; label: string; sensitive: boolean; hint: string }[] = [
  { key: 'model', label: '模型', sensitive: false, hint: '留空保持现状;未覆盖时继承默认' },
  { key: 'base_url', label: '接口地址', sensitive: false, hint: '留空保持现状;未覆盖时继承全局' },
  { key: 'api_key', label: 'API Key', sensitive: true, hint: '留空保持现状;未覆盖时继承全局' },
]

const KEY_BY_FIELD: Record<FieldKey, (id: string) => string> = {
  model: id => `AGENT_${id.toUpperCase()}_MODEL`,
  base_url: id => `AGENT_${id.toUpperCase()}_BASE_URL`,
  api_key: id => `AGENT_${id.toUpperCase()}_API_KEY`,
}

export default function AgentLLMCard() {
  const [agents, setAgents] = useState<LLMAgentConfig[]>([])
  const [loading, setLoading] = useState(true)
  const [expandedId, setExpandedId] = useState<string | null>(null)
  const [form, setForm] = useState<Record<FieldKey, string>>({ model: '', base_url: '', api_key: '' })
  const [busy, setBusy] = useState(false)
  const [notice, setNotice] = useState<{ ok: boolean; text: string } | null>(null)

  const load = useCallback(async () => {
    setLoading(true)
    try {
      setAgents(await fetchLLMAgents())
    } catch {
      setAgents([])
    } finally {
      setLoading(false)
    }
  }, [])

  useEffect(() => {
    load()
  }, [load])

  function toggleExpand(agent: LLMAgentConfig) {
    if (expandedId === agent.id) {
      setExpandedId(null)
      return
    }
    setExpandedId(agent.id)
    setNotice(null)
    // 预填非敏感覆盖值;API Key 不回填
    setForm({
      model: agent.fields.model.origin === 'db' ? agent.fields.model.masked : '',
      base_url: agent.fields.base_url.origin === 'db' ? agent.fields.base_url.masked : '',
      api_key: '',
    })
  }

  async function handleSave(agent: LLMAgentConfig) {
    setBusy(true)
    setNotice(null)
    try {
      const nonEmpty = (FIELD_META.filter(f => form[f.key].trim())).map(f => f)
      if (nonEmpty.length === 0) {
        setNotice({ ok: false, text: '没有需要保存的修改(全部为空)' })
        return
      }
      for (const f of nonEmpty) {
        await updateSetting(KEY_BY_FIELD[f.key](agent.id), form[f.key].trim())
      }
      setNotice({ ok: true, text: `${agent.label} 配置已保存,立即生效` })
      setExpandedId(null)
      await load()
    } catch (err) {
      setNotice({ ok: false, text: err instanceof Error ? err.message.split('\n')[0] : '保存失败' })
    } finally {
      setBusy(false)
    }
  }

  async function handleReset(agent: LLMAgentConfig) {
    setBusy(true)
    setNotice(null)
    try {
      for (const f of FIELD_META) {
        await clearSetting(KEY_BY_FIELD[f.key](agent.id))
      }
      setNotice({ ok: true, text: `${agent.label} 已恢复继承默认` })
      setExpandedId(null)
      await load()
    } catch (err) {
      setNotice({ ok: false, text: err instanceof Error ? err.message.split('\n')[0] : '恢复失败' })
    } finally {
      setBusy(false)
    }
  }

  const hasOverride = (agent: LLMAgentConfig) =>
    Object.values(agent.fields).some(f => f.origin === 'db')

  return (
    <Card>
      <CardHeader
        title="专家与终裁 LLM 配置"
        description="可为每个角色单独指定模型、接口地址或 API Key;未覆盖的角色按「专家层/终裁层默认 → 全局」继承"
        action={
          <button onClick={load} disabled={loading} className="btn btn-sm">
            {loading ? (<><Spinner /> 加载中</>) : '刷新'}
          </button>
        }
      />
      <CardBody className="px-0 sm:px-0">
        {loading ? (
          <div className="space-y-2 px-4 sm:px-5">
            {[1, 2, 3, 4, 5, 6].map(i => <SkeletonBlock key={i} className="h-9 w-full" />)}
          </div>
        ) : agents.length === 0 ? (
          <p className="py-6 text-center text-xs text-ink-400">无法加载角色配置</p>
        ) : (
          <>
            {notice && (
              <div className="px-4 pb-2 sm:px-5">
                <Alert kind={notice.ok ? 'ok' : 'error'} title={notice.text} />
              </div>
            )}
            {agents.map(agent => {
              const expanded = expandedId === agent.id
              return (
                <div key={agent.id} className="border-b border-ink-200 last:border-b-0">
                  {/* 行:角色名 + 生效模型 + 配置按钮 */}
                  <div className="flex flex-wrap items-center justify-between gap-x-3 gap-y-1 px-4 py-2.5 sm:px-5">
                    <div className="flex min-w-0 flex-wrap items-center gap-x-2 gap-y-1">
                      <span className="font-serif text-sm font-bold text-ink-900">{agent.label}</span>
                      {hasOverride(agent) && <Badge status="success">独立配置</Badge>}
                    </div>
                    <div className="flex min-w-0 items-center gap-2">
                      <span className="truncate font-mono text-2xs text-ink-500">{agent.effective_model}</span>
                      <button onClick={() => toggleExpand(agent)} disabled={busy} className="btn btn-sm flex-shrink-0">
                        {expanded ? '收起' : '配置'}
                      </button>
                    </div>
                  </div>

                  {/* 展开的编辑表单 */}
                  {expanded && (
                    <div className="space-y-3 border-t border-ink-200 bg-paper-100/40 px-4 py-3 sm:px-5">
                      {FIELD_META.map(f => {
                        const state = agent.fields[f.key]
                        return (
                          <div key={f.key} className="grid gap-1 sm:grid-cols-[96px_minmax(0,1fr)] sm:items-center sm:gap-3">
                            <label className="text-xs text-ink-500">{f.label}</label>
                            <div>
                              <input
                                type={f.sensitive ? 'password' : 'text'}
                                value={form[f.key]}
                                onChange={e => setForm(prev => ({ ...prev, [f.key]: e.target.value }))}
                                placeholder={
                                  f.key === 'api_key' && state.origin === 'db'
                                    ? `已覆盖(${state.masked}),留空保持不变`
                                    : f.hint
                                }
                                autoComplete="off"
                                className="field w-full"
                              />
                            </div>
                          </div>
                        )
                      })}

                      <div className="flex items-center justify-between gap-2 pt-1">
                        <p className="text-2xs text-ink-400">
                          生效模型:{agent.effective_model}
                        </p>
                        <div className="flex gap-2">
                          {hasOverride(agent) && (
                            <button onClick={() => handleReset(agent)} disabled={busy} className="btn btn-sm">
                              恢复继承
                            </button>
                          )}
                          <button onClick={() => handleSave(agent)} disabled={busy} className="btn btn-solid btn-sm">
                            {busy ? (<><Spinner /> 保存中</>) : '保存'}
                          </button>
                        </div>
                      </div>
                    </div>
                  )}
                </div>
              )
            })}
          </>
        )}
      </CardBody>
    </Card>
  )
}