import { useState, useEffect, useCallback } from 'react'
import { useTranslation } from 'react-i18next'
import { Sparkles, Play, AlertCircle } from 'lucide-react'
import { useProjectStore } from '../../stores/project-store'
import { useLLMStore } from '../../stores/llm-store'
import { useWorkflowStore } from '../../stores/workflow-store'

import { createChapterWorkflow } from '../../services/workflows/chapter-workflow'
import { guardChapterWriting } from '../../services/workflow-guards'
import { ipc } from '../../services/ipc-client'
import { toast } from '../ui/Toast'
import {
  Dialog, DialogContent, DialogHeader, DialogFooter, DialogTitle, DialogDescription,
} from '../ui/Dialog'
import { Button } from '../ui/Button'
import { Input } from '../ui/Input'
import { Textarea } from '../ui/Textarea'
import { Label } from '../ui/Label'
import { NativeSelect } from '../ui/NativeSelect'

interface Props {
  isOpen: boolean
  onClose: () => void
  /** 从章节蓝图「写作此章」传入的预填参数，优先级高于历史记录 */
  prefill?: Record<string, unknown> | null
}

/** 章节创作参数持久化路径（相对于项目路径） */
const CREATION_LOG_REL = '.vela/chapter_creation_log.json'

/** 章节创作对话框 — 配置并启动章节创作工作流（步进式，每步等待用户确认） */
export default function ChapterCreationDialog({ isOpen, onClose, prefill }: Props) {
  const { t } = useTranslation('dialogs')
  const currentProject = useProjectStore(s => s.currentProject)
  const defaultModelId = useLLMStore(s => s.defaultModelId)
  // ✅ action 用 getState() 获取，不订阅 workflow store 高频更新
  const startWorkflow = useWorkflowStore.getState().startWorkflow
  const addLog = useWorkflowStore.getState().addLog
  const [chapterNumber, setChapterNumber] = useState<number | ''>(1)
  const [title, setTitle] = useState('')
  const [role, setRole] = useState('发展')
  const [purpose, setPurpose] = useState('')
  const [keyEvents, setKeyEvents] = useState('')
  const [characters, setCharacters] = useState('')
  const [userGuidance, setUserGuidance] = useState('')
  const [knowledgeHint, setKnowledgeHint] = useState('')
  const [wordsTarget, setWordsTarget] = useState<number | ''>(3000)
  const [loadedFromHistory, setLoadedFromHistory] = useState(false)
  const [loadedFromBlueprint, setLoadedFromBlueprint] = useState(false)
  const [guardError, setGuardError] = useState<string | null>(null)
  const isChapterRunning = useWorkflowStore(s => s.isTypeRunning('chapter_creation'))


  // 如果是在这弹窗里发起的任务，一旦跑完，isChapterRunning 会变成 false，此时自动关闭弹窗
  useEffect(() => {
    let prevRunning = false
    const unsub = useWorkflowStore.subscribe((state) => {
      const running = state.isTypeRunning('chapter_creation')
      if (prevRunning && !running && isOpen) {
        onClose()
      }
      prevRunning = running
    })
    return unsub
  }, [isOpen, onClose])

  /** 从项目本地 .vela/chapter_creation_log.json 读取上次参数 */
  const loadLastParams = useCallback(async () => {
    if (!currentProject) return
    try {
      const result = await ipc.invoke('fs:read-json', `${currentProject.path}/${CREATION_LOG_REL}`)
      if (result.success && result.data) {
        const log = result.data as {
          lastUsed?: {
            chapterNumber: number; title?: string; role: string
            purpose?: string; keyEvents?: string; characters?: string
            userGuidance?: string; wordsTarget?: number
          }
        }
        if (log.lastUsed) {
          const last = log.lastUsed
          // 章节号自动 +1
          setChapterNumber((last.chapterNumber || 0) + 1)
          setTitle('') // 标题不继承，让用户自填
          setRole(last.role || '发展')
          setPurpose(last.purpose || '')
          setKeyEvents(last.keyEvents || '')
          setCharacters(last.characters || '')
          setUserGuidance(last.userGuidance || '')
          setWordsTarget(last.wordsTarget || currentProject.novelConfig.wordsPerChapter || 3000)
          setLoadedFromHistory(true)
          return
        }
      }
    } catch { /* 文件不存在，使用默认值 */ }
    // 默认值：根据已有稿件数量推断下一章节号
    setWordsTarget(currentProject.novelConfig.wordsPerChapter || 3000)
    setChapterNumber(1)
    setLoadedFromHistory(false)
  }, [currentProject])

  // 每次打开时：prefill 优先，其次尝试从历史恢复
  useEffect(() => {
    if (!isOpen || !currentProject) return
    let mounted = true
    Promise.resolve().then(() => {
      if (!mounted) return
      if (prefill) {
        // 使用章节蓝图预填数据
        setChapterNumber(Number(prefill.chapterNumber) || 1)
        setTitle(String(prefill.title || ''))
        setRole(String(prefill.role || '发展'))
        setPurpose(String(prefill.purpose || ''))
        setKeyEvents(String(prefill.keyEvents || ''))
        setCharacters(String(prefill.characters || ''))
        setUserGuidance(String(prefill.userGuidance || ''))
        setWordsTarget(currentProject.novelConfig.wordsPerChapter || 3000)
        setLoadedFromBlueprint(true)
        setLoadedFromHistory(false)
      } else {
        setLoadedFromBlueprint(false)
        loadLastParams()
      }
    })
    return () => { mounted = false }
  }, [isOpen, currentProject, prefill, loadLastParams])



  /** 保存当前参数到持久化文件 */
  const saveParams = async () => {
    if (!currentProject) return
    try {
      // 读取已有 log
      let log: { lastUsed?: object; history?: object[] } = {}
      const existing = await ipc.invoke('fs:read-json', `${currentProject.path}/${CREATION_LOG_REL}`)
      if (existing.success && existing.data) {
        log = existing.data as typeof log
      }

      const params = { chapterNumber, title, role, purpose, keyEvents, characters, userGuidance, wordsTarget }
      log.lastUsed = params
      log.history = [
        { ...params, createdAt: new Date().toISOString() },
        ...((log.history || []) as object[]).slice(0, 49), // 最多保留 50 条历史
      ]

      await ipc.invoke('fs:write-json', `${currentProject.path}/${CREATION_LOG_REL}`, log)
    } catch (e) {
      console.warn('[ChapterCreation] 参数持久化失败:', e)
    }
  }

  const handleStart = async () => {
    if (!defaultModelId) {
      addLog('error', t('chapterCreation.needModel'))
      return
    }
    if (!currentProject) return

    // 防重复：同类型工作流正在运行
    if (isChapterRunning) {
      toast.warning(t('chapterCreation.taskRunning'))
      return
    }

    // 前置校验：章节蓝图是否已生成，以及（若篇章>1）前一章是否已定稿
    const targetChapter = Number(chapterNumber) || 1
    const guard = await guardChapterWriting(targetChapter)
    if (!guard.ok) {
      setGuardError(guard.message || t('chapterCreation.prereqNotMet'))
      return
    }
    setGuardError(null)

    // 持久化本次参数
    await saveParams()

    const workflow = createChapterWorkflow({
      chapterNumber: Number(chapterNumber) || 1,
      title: title || t('chapterCreation.defaultTitle', { chapterNumber: chapterNumber || 1 }),
      role,
      purpose,
      characters: characters.split(/[、,，]/).map(s => s.trim()).filter(Boolean),
      keyEvents,
      userGuidance,
      knowledgeQueryHint: knowledgeHint.trim() || undefined,
    })

    // 启动任务后关闭设定弹窗，由全局 Overlay 接管展示
    startWorkflow(workflow, false)
    onClose()
  }

  const handleOpenChange = (open: boolean) => {
    // 如果正在生成中，禁止通过点击外部或 ESC 关闭
    if (!open && !isChapterRunning) onClose()
  }

  return (
    <Dialog open={isOpen} onOpenChange={handleOpenChange}>
      <DialogContent className="max-w-[540px]">
        <DialogHeader>
          <DialogTitle className="flex items-center gap-2">
            <Sparkles size={16} className="text-[var(--color-accent)]" />
            {t('chapterCreation.title')}
          </DialogTitle>
          <DialogDescription>
            {t('chapterCreation.description')}
            {loadedFromBlueprint && (
              <span className="ml-2 text-[0.7rem] px-1.5 py-0.5 rounded-full bg-green-500/15 text-green-600 dark:text-green-400">
                {t('chapterCreation.prefilledFromBlueprint')}
              </span>
            )}
            {loadedFromHistory && !loadedFromBlueprint && (
              <span className="ml-2 text-[0.7rem] px-1.5 py-0.5 rounded-full" style={{ backgroundColor: 'rgba(var(--color-accent-rgb), 0.15)', color: 'var(--color-accent)' }}>
                {t('chapterCreation.prefilledFromLast')}
              </span>
            )}
          </DialogDescription>
        </DialogHeader>

        {/* 表单 */}
        <div className="px-5 py-4 space-y-3">
              <div className="grid grid-cols-3 gap-3">
                <div>
                  <Label>{t('chapterCreation.chapterNumber')}</Label>
                  <Input
                    type="number"
                    value={chapterNumber}
                    onChange={(e) => setChapterNumber(e.target.value === '' ? '' : parseInt(e.target.value))}
                    onBlur={() => {
                      const v = Number(chapterNumber)
                      if (!v || v < 1) setChapterNumber(1)
                    }}
                    placeholder="1"
                    min={1}
                  />
                </div>
                <div>
                  <Label>{t('chapterCreation.chapterTitle')}</Label>
                  <Input value={title} onChange={(e) => setTitle(e.target.value)} placeholder={t('chapterCreation.titlePlaceholder')} />
                </div>
                <div>
                  <Label>{t('chapterCreation.targetWords')}</Label>
                  <Input
                    type="number"
                    value={wordsTarget}
                    onChange={(e) => setWordsTarget(e.target.value === '' ? '' : parseInt(e.target.value))}
                    onBlur={() => {
                      const v = Number(wordsTarget)
                      if (!v || v < 100) setWordsTarget(3000)
                    }}
                    placeholder="3000"
                    min={100}
                    step={500}
                  />
                </div>
              </div>

              <div className="grid grid-cols-2 gap-3">
                <div>
                  <Label>{t('chapterCreation.chapterRole')}</Label>
                  <NativeSelect value={role} onChange={(e) => setRole(e.target.value)}>
                    {[
                      { key: 'opening', value: '开篇' },
                      { key: 'setup', value: '铺垫' },
                      { key: 'development', value: '发展' },
                      { key: 'conflict', value: '冲突' },
                      { key: 'climax', value: '高潮' },
                      { key: 'turning', value: '转折' },
                      { key: 'resolution', value: '收尾' },
                    ].map((r) => (
                      <option key={r.key} value={r.value}>{t(`chapterCreation.roles.${r.key}`)}</option>
                    ))}
                  </NativeSelect>
                </div>
                <div>
                  <Label>{t('chapterCreation.characters')}</Label>
                  <Input value={characters} onChange={(e) => setCharacters(e.target.value)} placeholder={t('chapterCreation.charactersPlaceholder')} />
                </div>
              </div>

              <div>
                <Label>{t('chapterCreation.purpose')}</Label>
                <Textarea
                  value={purpose}
                  onChange={(e) => setPurpose(e.target.value)}
                  placeholder={t('chapterCreation.purposePlaceholder')}
                  rows={2}
                />
              </div>

              <div>
                <Label>{t('chapterCreation.keyEvents')}</Label>
                <Textarea
                  value={keyEvents}
                  onChange={(e) => setKeyEvents(e.target.value)}
                  placeholder={t('chapterCreation.keyEventsPlaceholder')}
                  rows={2}
                />
              </div>

              <div>
                <Label>{t('chapterCreation.authorGuidance')} <span className="text-[0.7rem] opacity-50">{t('chapterCreation.guidanceHint')}</span></Label>
                <Textarea
                  value={userGuidance}
                  onChange={(e) => setUserGuidance(e.target.value)}
                  placeholder={t('chapterCreation.guidancePlaceholder')}
                  rows={2}
                />
              </div>

              <div>
                <Label>{t('chapterCreation.kbKeywords')} <span className="text-[0.7rem] opacity-50">{t('chapterCreation.kbKeywordsHint')}</span></Label>
                <Input
                  value={knowledgeHint}
                  onChange={(e) => setKnowledgeHint(e.target.value)}
                  placeholder={t('chapterCreation.kbKeywordsPlaceholder')}
                />
              </div>
            </div>

            <DialogFooter className="sm:justify-between items-center">
              <span className="text-xs mt-2 sm:mt-0" style={{ color: 'var(--color-text-muted)' }}>
                {t('chapterCreation.workflowInfo')}
              </span>
              <div className="flex items-center gap-2">
                <Button variant="outline" onClick={onClose}>{t('common.cancel')}</Button>
                <Button variant="ai" size="lg" onClick={handleStart} disabled={isChapterRunning}>
                  {isChapterRunning ? (
                    <span className="flex items-center gap-2">
                      <span className="animate-spin" style={{ filter: 'brightness(1.5)' }}>🌀</span>
                      {t('chapterCreation.creating')}
                    </span>
                  ) : (
                    <span className="flex items-center gap-2">
                      <Play size={13} />
                      {t('chapterCreation.startCreation')}
                    </span>
                  )}
                </Button>
              </div>
            </DialogFooter>
            {/* 前置校验失败提示（呈现在 Footer 下方） */}
            {guardError && (
              <div className="mx-5 mb-4 flex items-start gap-2 px-3 py-2.5 rounded-lg text-xs bg-yellow-500/10 border border-yellow-500/30 text-yellow-600 dark:text-yellow-400">
                <AlertCircle size={13} className="flex-shrink-0 mt-0.5 text-yellow-500" />
                <span className="whitespace-pre-line">{guardError}</span>
              </div>
            )}
      </DialogContent>
    </Dialog>
  )
}