import { memo, useEffect, useState } from 'react'
import { useTranslation } from 'react-i18next'
import { useForm } from 'react-hook-form'
import { zodResolver } from '@hookform/resolvers/zod'
import { z } from 'zod'
import { toast } from 'sonner'
import { deploymentApi } from '@/api'
import { Button } from '@/components/ui/button'
import { Dialog, DialogContent, DialogHeader, DialogTitle } from '@/components/ui/dialog'
import { Form, FormControl, FormField, FormItem, FormLabel, FormMessage } from '@/components/ui/form'
import { Textarea } from '@/components/ui/textarea'
import i18n from '@/i18n'
import type { LokiDeployment } from '@/types'

const schema = z.object({ yaml: z.string().trim().min(1, i18n.t('deployments:retention.yamlRequired')) })
type Values = z.infer<typeof schema>

interface Props {
  deployment: LokiDeployment | null
  onClose: () => void
  onSaved: () => void
}

function configLocation(deployment: LokiDeployment, t: (k: string, o?: Record<string, unknown>) => string) {
  if (deployment.mode === 'host-binary') return t('retention.locationHostBinary')
  if (deployment.mode === 'host-docker') return t('retention.locationHostDocker', { id: deployment.id })
  return t('retention.locationK8s', { namespace: deployment.namespace || 'log' })
}

export const RetentionDialog = memo(function RetentionDialog({ deployment, onClose, onSaved }: Props) {
  const { t } = useTranslation('deployments')
  const [saving, setSaving] = useState(false)
  const [liveConfig, setLiveConfig] = useState<{ location: string; yaml: string } | null>(null)
  const [configLoading, setConfigLoading] = useState(false)
  const [configError, setConfigError] = useState('')
  const form = useForm<Values>({
    resolver: zodResolver(schema),
    defaultValues: { yaml: 'limits_config:\n  retention_period: 30d\n' },
  })

  useEffect(() => {
    if (deployment) {
      form.reset({ yaml: `limits_config:\n  retention_period: ${deployment.retentionDays || 30}d\n` })
    }
    setLiveConfig(null)
    setConfigError('')
  }, [deployment, form])

  const loadConfig = async () => {
    if (!deployment) return
    setConfigLoading(true)
    setConfigError('')
    try {
      setLiveConfig(await deploymentApi.liveConfig(deployment.id))
    } catch (err) {
      setConfigError(err instanceof Error ? err.message : t('retention.errLoad'))
    } finally {
      setConfigLoading(false)
    }
  }

  const save = (apply: boolean) => form.handleSubmit(async ({ yaml }) => {
    if (!deployment) return
    setSaving(true)
    try {
      const result = await deploymentApi.updateRetention(deployment.id, yaml, apply)
      onSaved()
      onClose()
      if (apply) toast.info(t('retention.savedApplied', { days: result.retentionDays }))
    } catch (err) {
      toast.error(err instanceof Error ? err.message : t('retention.errSave'))
      onSaved()
    } finally {
      setSaving(false)
    }
  })

  return (
    <Dialog open={deployment !== null} onOpenChange={(open) => { if (!open && !saving) onClose() }}>
      <DialogContent className="sm:max-w-4xl max-h-[90vh] overflow-y-auto">
        <DialogHeader>
          <DialogTitle>{deployment ? t('retention.title', { name: deployment.name }) : ''}</DialogTitle>
        </DialogHeader>
        <div className="space-y-1 text-sm text-muted-foreground">
          <p>{t('retention.locationLabel')}{deployment ? configLocation(deployment, t) : ''}</p>
          <p>{t('retention.compactorNote')}</p>
        </div>
        <div className="space-y-2 rounded-md border border-border p-3">
          <div className="flex items-center justify-between gap-3">
            <div>
              <p className="text-sm font-medium">{t('retention.liveTitle')}</p>
              <p className="text-xs text-muted-foreground">{t('retention.liveHint')}</p>
            </div>
            <Button type="button" variant="outline" size="sm" onClick={loadConfig} disabled={configLoading}>
              {configLoading ? t('retention.loading') : liveConfig ? t('retention.refresh') : t('retention.view')}
            </Button>
          </div>
          {configError && <p className="text-sm text-destructive">{configError}</p>}
          {liveConfig && (
            <div>
              <p className="mb-2 text-xs text-muted-foreground">{liveConfig.location}</p>
              <pre className="max-h-[45vh] max-w-full overflow-auto rounded-md bg-muted/50 p-3 font-mono text-xs whitespace-pre">{liveConfig.yaml}</pre>
            </div>
          )}
        </div>
        <div className="rounded-md border border-border bg-muted/40 p-3 text-xs">
          <p className="mb-1 font-medium text-foreground">{t('retention.templateNote')}</p>
          <pre className="text-muted-foreground">{'compactor:\n  retention_enabled: true\n  retention_delete_delay: 2h'}</pre>
        </div>
        <Form {...form}>
          <form onSubmit={save(false)} className="space-y-4">
            <FormField
              control={form.control}
              name="yaml"
              render={({ field }) => (
                <FormItem>
                  <FormLabel>{t('retention.yamlLabel')}</FormLabel>
                  <FormControl>
                    <Textarea rows={4} spellCheck={false} className="font-mono text-sm" {...field} />
                  </FormControl>
                  <p className="text-xs text-muted-foreground">{t('retention.yamlHint')}</p>
                  <FormMessage />
                </FormItem>
              )}
            />
            <p className="text-sm text-muted-foreground">
              {deployment?.status === 'running' ? t('retention.applyHintRunning') : t('retention.applyHintIdle')}
            </p>
            <div className="flex justify-end gap-2">
              <Button type="button" variant="outline" onClick={onClose} disabled={saving}>{t('retention.cancel')}</Button>
              <Button type="submit" variant="outline" disabled={saving}>{t('retention.saveOnly')}</Button>
              {deployment?.status === 'running' && (
                <Button type="button" onClick={save(true)} disabled={saving}>
                  {saving ? t('retention.processing') : t('retention.saveApply')}
                </Button>
              )}
            </div>
          </form>
        </Form>
      </DialogContent>
    </Dialog>
  )
})