'use client'

import { useState, useTransition } from 'react'
import { Category, Product, ProductModule } from '@/lib/types'
import { updateProduct, createProduct, updateCategory, createCategory, deleteProduct, deleteCategory } from '@/lib/actions/products'
import { InlineInput } from './components/inline-input'
import { ModulePopover } from './components/module-popover'
import { Trash2 } from 'lucide-react'

export function WysiwygAdminClient({
  initialCategories,
  initialProducts,
  allModules
}: {
  initialCategories: Category[]
  initialProducts: Product[]
  allModules: ProductModule[]
}) {
  const [mode, setMode] = useState<'purchase' | 'subscription'>('purchase')
  const [categories, setCategories] = useState(initialCategories)
  const [products, setProducts] = useState(initialProducts)
  const [isPending, startTransition] = useTransition()

  const handleDeleteCategory = async (catId: string) => {
    // Cascade-Check: check if there are products belonging to this category
    const categoryProducts = products.filter(p => p.category_id === catId)
    if (categoryProducts.length > 0) {
      alert(`Diese Kategorie enthält noch ${categoryProducts.length} Produkte. Bitte lösche oder verschiebe diese zuerst!`)
      return
    }

    if (!window.confirm('Möchten Sie diese Kategorie wirklich löschen?')) {
      return
    }

    startTransition(async () => {
      try {
        await deleteCategory(catId)
        setCategories(categories.filter(c => c.id !== catId))
      } catch (e) {
        console.error(e)
        alert('Fehler beim Löschen der Kategorie.')
      }
    })
  }

  const handleDeleteProduct = async (prodId: string) => {
    if (!window.confirm('Möchten Sie dieses Produkt wirklich löschen?')) {
      return
    }

    startTransition(async () => {
      try {
        await deleteProduct(prodId)
        setProducts(products.filter(p => p.id !== prodId))
      } catch (e) {
        console.error(e)
        alert('Fehler beim Löschen des Produkts.')
      }
    })
  }

  // Filterung der Kategorien nach aktivem Modus
  const filteredCategories = categories.filter(cat => 
    mode === 'purchase' ? cat.show_in_kauf : cat.show_in_abo
  )

  // Filterung der Produkte nach aktivem Modus
  const filteredProducts = products.filter(p => 
    mode === 'purchase' ? p.billing_interval === 'one_time' : p.billing_interval === 'monthly'
  )

  const handleAddCategory = async () => {
    startTransition(async () => {
      try {
        const newCat = await createCategory({
          name: 'Neue Kategorie',
          description: 'Beschreibung hier...',
          sort_order: categories.length + 1,
          is_required: false,
          allow_multiselect: false,
          free_items_limit: 0,
          preselect: false,
          show_in_kauf: mode === 'purchase',
          show_in_abo: mode === 'subscription'
        })
        setCategories([...categories, newCat])
      } catch (e) {
        console.error(e)
      }
    })
  }

  const handleAddProduct = async (categoryId: string) => {
    startTransition(async () => {
      try {
        const newProd = await createProduct({
          name: 'Neues Produkt',
          description: 'Produktbeschreibung...',
          base_price: 19.99,
          tax_rate: 19,
          billing_interval: mode === 'purchase' ? 'one_time' : 'monthly',
          category_id: categoryId,
          show_in_kauf: mode === 'purchase',
          show_in_abo: mode === 'subscription'
        }, [])
        setProducts([...products, newProd])
      } catch (e) {
        console.error(e)
      }
    })
  }

  const handleCategoryToggle = async (catId: string, fields: Partial<Category>) => {
    startTransition(async () => {
      try {
        setCategories(categories.map(c => c.id === catId ? { ...c, ...fields } : c))
        await updateCategory(catId, fields)
      } catch (e) {
        console.error(e)
      }
    })
  }

  return (
    <div className={`p-6 max-w-7xl mx-auto space-y-6 ${isPending ? 'opacity-70 pointer-events-none' : ''}`}>
      <div className="flex justify-between items-center border-b border-white/10 pb-4">
        <div className="flex space-x-4">
          <button
            onClick={() => setMode('purchase')}
            className={`px-4 py-2 rounded-lg font-medium transition ${
              mode === 'purchase' ? 'bg-primary text-black' : 'bg-white/5 text-white hover:bg-white/10'
            }`}
          >
            Kauf-Modus (Einmalig)
          </button>
          <button
            onClick={() => setMode('subscription')}
            className={`px-4 py-2 rounded-lg font-medium transition ${
              mode === 'subscription' ? 'bg-primary text-black' : 'bg-white/5 text-white hover:bg-white/10'
            }`}
          >
            Abo-Modus (Monatlich)
          </button>
        </div>
        {isPending && <span className="text-xs text-primary animate-pulse font-medium">Speichere Änderungen...</span>}
      </div>

      <div className="space-y-8">
        {filteredCategories
          .sort((a, b) => a.sort_order - b.sort_order)
          .map(cat => {
            const catProducts = filteredProducts.filter(p => p.category_id === cat.id)
            return (
              <div key={cat.id} className="p-6 bg-white/5 border border-white/10 rounded-2xl space-y-4 shadow-xl">
                <div className="flex justify-between items-start border-b border-white/5 pb-4">
                  <div className="w-full">
                    <InlineInput
                      value={cat.name}
                      onSave={async (newName) => {
                        await updateCategory(cat.id, { name: newName })
                        setCategories(categories.map(c => c.id === cat.id ? { ...c, name: newName } : c))
                      }}
                      className="text-2xl font-bold text-white block w-full"
                    />
                    <InlineInput
                      value={cat.description || ''}
                      onSave={async (newDesc) => {
                        await updateCategory(cat.id, { description: newDesc })
                        setCategories(categories.map(c => c.id === cat.id ? { ...c, description: newDesc } : c))
                      }}
                      className="text-slate-400 text-sm mt-1 block w-full"
                    />
                    
                    {/* Kategorie Attribute (Toggles) */}
                    <div className="flex items-center gap-6 mt-3 text-xs text-slate-400">
                      <label className="flex items-center gap-2 cursor-pointer select-none">
                        <input
                          type="checkbox"
                          checked={cat.is_required}
                          onChange={(e) => handleCategoryToggle(cat.id, { is_required: e.target.checked })}
                          className="rounded border-white/10 bg-white/5 text-primary focus:ring-0 focus:ring-offset-0"
                        />
                        <span>Pflichtauswahl (is_required)</span>
                      </label>
                      <label className="flex items-center gap-2 cursor-pointer select-none">
                        <input
                          type="checkbox"
                          checked={cat.allow_multiselect}
                          onChange={(e) => handleCategoryToggle(cat.id, { allow_multiselect: e.target.checked })}
                          className="rounded border-white/10 bg-white/5 text-primary focus:ring-0 focus:ring-offset-0"
                        />
                        <span>Mehrfachauswahl (allow_multiselect)</span>
                      </label>
                    </div>
                  </div>
                  <button
                    onClick={() => handleDeleteCategory(cat.id)}
                    className="p-2 text-slate-500 hover:text-red-500 hover:bg-white/5 rounded-lg transition-all ml-4 flex-shrink-0"
                    title="Kategorie löschen"
                  >
                    <Trash2 className="w-5 h-5" />
                  </button>
                </div>

                <div className="grid grid-cols-1 md:grid-cols-3 gap-4 pt-2">
                  {catProducts.map(prod => (
                    <div key={prod.id} className="p-4 bg-white/5 border border-white/10 rounded-xl space-y-3 relative group flex flex-col justify-between">
                      <div className="space-y-2">
                        <div className="flex justify-between items-start gap-2">
                          <div className="flex-1">
                            <InlineInput
                              value={prod.name}
                              onSave={async (newName) => {
                                  await updateProduct(prod.id, { name: newName }, prod.modules || [])
                                  setProducts(products.map(p => p.id === prod.id ? { ...p, name: newName } : p))
                              }}
                              className="font-semibold text-white block"
                            />
                          </div>
                          <button
                            onClick={() => handleDeleteProduct(prod.id)}
                            className="p-1 text-slate-500 hover:text-red-500 hover:bg-white/5 rounded transition-all opacity-0 group-hover:opacity-100 flex-shrink-0"
                            title="Produkt löschen"
                          >
                            <Trash2 className="w-4 h-4" />
                          </button>
                        </div>
                        <InlineInput
                          value={prod.description || ''}
                          onSave={async (newDesc) => {
                            await updateProduct(prod.id, { description: newDesc }, prod.modules || [])
                            setProducts(products.map(p => p.id === prod.id ? { ...p, description: newDesc } : p))
                          }}
                          className="text-xs text-slate-400 block"
                        />
                        <div className="text-primary font-mono text-sm flex items-center space-x-1">
                          <InlineInput
                            value={prod.base_price.toString()}
                            type="number"
                            onSave={async (newPrice) => {
                              const priceNum = parseFloat(newPrice) || 0
                              await updateProduct(prod.id, { base_price: priceNum }, prod.modules || [])
                              setProducts(products.map(p => p.id === prod.id ? { ...p, base_price: priceNum } : p))
                            }}
                            className="inline-block"
                          /> 
                          <span>€</span>
                        </div>

                        {/* Modul-Badges */}
                        <div className="space-y-1">
                          <span className="text-[10px] uppercase tracking-wider text-slate-500 font-semibold block">Module:</span>
                          <div className="flex flex-wrap gap-1">
                            {(prod.modules || []).length > 0 ? (
                              (prod.modules || []).map((m) => (
                                <span key={m.id} className="inline-flex items-center gap-1 px-2 py-0.5 rounded text-[10px] bg-white/10 text-slate-300 font-medium">
                                  {m.name}
                                  <button
                                    onClick={async () => {
                                      const updatedModules = (prod.modules || []).filter(mod => mod.id !== m.id)
                                      setProducts(products.map(p => p.id === prod.id ? { ...p, modules: updatedModules } : p))
                                      await updateProduct(prod.id, {}, updatedModules)
                                    }}
                                    className="text-slate-500 hover:text-white font-bold transition-colors ml-0.5"
                                    title="Modul entfernen"
                                  >
                                    ×
                                  </button>
                                </span>
                              ))
                            ) : (
                              <span className="text-[10px] text-slate-500 italic">Keine Module</span>
                            )}
                          </div>
                        </div>
                      </div>

                      {/* Modul hinzufügen Popover */}
                      <div className="mt-3 pt-2 border-t border-white/5">
                        <ModulePopover
                          assignedModules={prod.modules || []}
                          allModules={allModules}
                          onAddModule={async (mod) => {
                            const newMod = {
                              name: mod.name,
                              description: mod.description,
                              price: mod.price,
                              requirements: mod.requirements || [],
                              exclusions: mod.exclusions || [],
                              has_quantity: mod.has_quantity || false
                            }
                            const updatedModules = [...(prod.modules || []), newMod]
                            setProducts(products.map(p => p.id === prod.id ? { ...p, modules: updatedModules as any } : p))
                            await updateProduct(prod.id, {}, updatedModules)
                          }}
                        />
                      </div>
                    </div>
                  ))}

                  <button
                    onClick={() => handleAddProduct(cat.id)}
                    className="flex flex-col items-center justify-center p-4 border border-dashed border-white/20 hover:border-primary/50 rounded-xl text-slate-400 hover:text-primary transition h-full min-h-[140px]"
                  >
                    <span className="text-2xl mb-1">+</span>
                    <span className="text-xs font-medium">Produkt hinzufügen</span>
                  </button>
                </div>
              </div>
            )
          })}

        <button
          onClick={handleAddCategory}
          className="w-full py-4 border border-dashed border-white/20 hover:border-primary/50 rounded-2xl flex items-center justify-center text-slate-400 hover:text-primary transition"
        >
          <span className="text-xl mr-2">+</span>
          <span className="font-medium">Neue Kategorie hinzufügen</span>
        </button>
      </div>
    </div>
  )
}
