'use client'

import { useEffect, useState } from 'react'
import { X, CheckSquare, BookOpen, GraduationCap, LayoutList } from 'lucide-react'
import { Button } from '@/components/ui/button'
import { useLanguage } from '@/lib/i18n'
import { toast } from 'sonner'
import type { NotesLayoutMode } from '@/components/notes-list-views'
import {
  WIZARD_DEFAULT_VIEW,
  WIZARD_FIELDS_BY_GOAL,
  WIZARD_GOALS,
  type WizardFieldDef,
  type WizardFieldId,
  type WizardGoal,
} from '@/lib/structured-views/wizard-templates'
import { cn } from '@/lib/utils'

type StructuredViewsWizardProps = {
  open: boolean
  onClose: () => void
  onComplete: (view: NotesLayoutMode) => void
  structuredModeActive: boolean
  enableStructuredMode: () => Promise<unknown>
  addProperty: (name: string, type: string, options?: string[]) => Promise<{ properties: { id: string; name: string; type: string }[] } | null | undefined>
  setKanbanGroupProperty: (propertyId: string | null) => Promise<void>
  initialGoal?: WizardGoal
}

const GOAL_ICONS: Record<WizardGoal, React.ElementType> = {
  tasks: CheckSquare,
  learning: GraduationCap,
  reading: BookOpen,
  simple: LayoutList,
}

const VIEW_LABEL_KEYS: Record<'list' | 'gallery' | 'table' | 'kanban', string> = {
  list: 'structuredViews.viewList',
  gallery: 'structuredViews.viewGallery',
  table: 'structuredViews.viewTable',
  kanban: 'structuredViews.viewKanban',
}

export function StructuredViewsWizard({
  open,
  onClose,
  onComplete,
  structuredModeActive,
  enableStructuredMode,
  addProperty,
  setKanbanGroupProperty,
  initialGoal,
}: StructuredViewsWizardProps) {
  const { t } = useLanguage()
  const [step, setStep] = useState(0)
  const [goal, setGoal] = useState<WizardGoal>('tasks')
  const [selectedFields, setSelectedFields] = useState<Set<WizardFieldId>>(new Set())
  const [view, setView] = useState<NotesLayoutMode>('list')
  const [saving, setSaving] = useState(false)

  const fieldDefs = WIZARD_FIELDS_BY_GOAL[goal]

  useEffect(() => {
    if (!open) return
    const g = initialGoal ?? 'tasks'
    setStep(0)
    setGoal(g)
    setSelectedFields(new Set(WIZARD_FIELDS_BY_GOAL[g].map((f) => f.id)))
    setView(WIZARD_DEFAULT_VIEW[g])
  }, [open, initialGoal])

  useEffect(() => {
    setSelectedFields(new Set(fieldDefs.map((f) => f.id)))
    setView(WIZARD_DEFAULT_VIEW[goal])
  }, [goal, fieldDefs])

  const kanbanAllowed = fieldDefs.some((f) => f.type === 'select' && selectedFields.has(f.id))

  if (!open) return null

  const toggleField = (id: WizardFieldId) => {
    setSelectedFields((prev) => {
      const next = new Set(prev)
      if (next.has(id)) next.delete(id)
      else next.add(id)
      return next
    })
  }

  const fieldLabel = (def: WizardFieldDef) => t(`structuredViews.wizard.fields.${def.id}.name`)

  const parseOptions = (fieldId: WizardFieldId) =>
    t(`structuredViews.wizard.fields.${fieldId}.options`)
      .split('\n')
      .map((l) => l.trim())
      .filter(Boolean)

  const handleFinish = async () => {
    setSaving(true)
    try {
      if (!structuredModeActive) await enableStructuredMode()

      let kanbanPropertyId: string | null = null

      for (const def of fieldDefs) {
        if (!selectedFields.has(def.id)) continue
        const name = fieldLabel(def)
        const options = def.hasOptions ? parseOptions(def.id) : []
        const schema = await addProperty(name, def.type, options)
        const created = schema?.properties.find((p) => p.name === name)
        if (created && def.type === 'select' && !kanbanPropertyId) {
          kanbanPropertyId = created.id
        }
      }

      const finalView = view === 'kanban' && !kanbanAllowed ? 'list' : view
      if (finalView === 'kanban' && kanbanPropertyId) {
        await setKanbanGroupProperty(kanbanPropertyId)
      }

      onComplete(finalView)
      onClose()
    } catch {
      toast.error(t('structuredViews.enableFailed'))
    } finally {
      setSaving(false)
    }
  }

  const goNext = () => {
    if (step === 0 && goal === 'simple') {
      setStep(2)
      return
    }
    setStep((s) => Math.min(s + 1, 2))
  }

  return (
    <div className="fixed inset-0 z-[210] flex items-center justify-center p-4 bg-black/40 backdrop-blur-sm">
      <div
        role="dialog"
        aria-modal
        className="w-full max-w-lg rounded-2xl border border-border bg-card shadow-xl p-6 space-y-5"
      >
        <div className="flex items-start justify-between gap-4">
          <div>
            <h2 className="font-memento-serif text-xl">{t('structuredViews.wizard.title')}</h2>
            <p className="text-[13px] text-muted-foreground mt-1">{t('structuredViews.wizard.subtitle')}</p>
          </div>
          <button type="button" onClick={onClose} className="p-1 rounded-lg hover:bg-foreground/5 shrink-0">
            <X size={18} />
          </button>
        </div>

        {step === 0 && (
          <div className="space-y-3">
            <p className="text-[10px] uppercase tracking-widest font-bold text-muted-foreground">
              {t('structuredViews.wizard.stepGoal')}
            </p>
            <div className="grid gap-2">
              {WIZARD_GOALS.map((g) => {
                const Icon = GOAL_ICONS[g]
                return (
                  <button
                    key={g}
                    type="button"
                    onClick={() => setGoal(g)}
                    className={cn(
                      'flex items-start gap-3 rounded-xl border p-3 text-left transition-colors',
                      goal === g
                        ? 'border-foreground bg-foreground/[0.04]'
                        : 'border-border hover:border-foreground/25',
                    )}
                  >
                    <Icon size={18} className="mt-0.5 shrink-0 text-muted-foreground" />
                    <div>
                      <div className="text-[13px] font-medium">{t(`structuredViews.wizard.goals.${g}.title`)}</div>
                      <div className="text-[12px] text-muted-foreground mt-0.5">
                        {t(`structuredViews.wizard.goals.${g}.desc`)}
                      </div>
                    </div>
                  </button>
                )
              })}
            </div>
          </div>
        )}

        {step === 1 && fieldDefs.length > 0 && (
          <div className="space-y-3">
            <p className="text-[10px] uppercase tracking-widest font-bold text-muted-foreground">
              {t('structuredViews.wizard.stepFields')}
            </p>
            <p className="text-[12px] text-muted-foreground">{t('structuredViews.wizard.fieldsHint')}</p>
            <div className="space-y-2">
              {fieldDefs.map((def) => (
                <label
                  key={def.id}
                  className="flex items-center gap-3 rounded-xl border border-border px-3 py-2.5 cursor-pointer hover:bg-foreground/[0.02]"
                >
                  <input
                    type="checkbox"
                    checked={selectedFields.has(def.id)}
                    onChange={() => toggleField(def.id)}
                    className="rounded border-border"
                  />
                  <span className="text-[13px] font-medium">{fieldLabel(def)}</span>
                  <span className="text-[10px] text-muted-foreground ms-auto uppercase">
                    {t(`structuredViews.propertyTypes.${def.type}`)}
                  </span>
                </label>
              ))}
            </div>
          </div>
        )}

        {step === 2 && (
          <div className="space-y-3">
            <p className="text-[10px] uppercase tracking-widest font-bold text-muted-foreground">
              {t('structuredViews.wizard.stepView')}
            </p>
            <div className="grid grid-cols-2 gap-2">
              {(['list', 'gallery', 'table', 'kanban'] as const).map((v) => {
                const disabled = v === 'kanban' && !kanbanAllowed
                return (
                  <button
                    key={v}
                    type="button"
                    disabled={disabled}
                    onClick={() => setView(v)}
                    className={cn(
                      'rounded-xl border px-3 py-3 text-[12px] font-bold uppercase tracking-wider transition-colors',
                      view === v
                        ? 'border-foreground bg-foreground text-background'
                        : 'border-border text-muted-foreground hover:border-foreground/30',
                      disabled && 'opacity-40 cursor-not-allowed',
                    )}
                  >
                    {t(VIEW_LABEL_KEYS[v])}
                  </button>
                )
              })}
            </div>
            {view === 'kanban' && !kanbanAllowed && (
              <p className="text-[12px] text-muted-foreground">{t('structuredViews.wizard.kanbanNeedsStatus')}</p>
            )}
            <p className="text-[12px] text-muted-foreground">{t('structuredViews.wizard.doneHint')}</p>
          </div>
        )}

        <div className="flex justify-between gap-2 pt-2">
          <Button
            type="button"
            variant="ghost"
            onClick={() => (step === 0 ? onClose() : setStep((s) => s - 1))}
            disabled={saving}
          >
            {step === 0 ? t('general.cancel') : t('structuredViews.wizard.back')}
          </Button>
          {step < 2 ? (
            <Button type="button" onClick={goNext}>
              {t('structuredViews.wizard.next')}
            </Button>
          ) : (
            <Button type="button" onClick={() => void handleFinish()} disabled={saving}>
              {saving ? t('general.loading') : t('structuredViews.wizard.finish')}
            </Button>
          )}
        </div>
      </div>
    </div>
  )
}