import { NextRequest, NextResponse } from 'next/server';
import { createServerClient } from '@/lib/supabase/server';
import { z } from 'zod';

const addItemSchema = z.object({
  householdId: z.string().min(1).default('demo-household-id'),
  shoppingListId: z.string().optional().nullable(),
  productId: z.string().optional().nullable(),
  customName: z.string().optional().nullable(),
  quantity: z.coerce.number().positive().default(1),
  unitId: z.string().optional().nullable(),
  estimatedUnitPriceCents: z.coerce.number().int().nonnegative().optional().nullable(),
  selectedStore: z.string().optional().nullable(),
  notes: z.string().optional().nullable(),
});

interface LocalShoppingItem {
  id: string;
  shoppingListId: string;
  productId: string | null;
  customName: string;
  displayName: string;
  quantity: number;
  unitName: string;
  estimatedUnitPriceCents: number;
  totalEstimatedPriceCents: number;
  selectedStore: string;
  checked: boolean;
  automaticallyAdded: boolean;
  createdAt: string;
}

// In-memory persistent shopping list store for seamless local testing
let LOCAL_SHOPPING_ITEMS: LocalShoppingItem[] = [
  {
    id: 'sli-1',
    shoppingListId: 'demo-shopping-list-id',
    productId: null,
    customName: 'Hafermilch Barista',
    displayName: '🥛 Hafermilch Barista (1 Liter)',
    quantity: 1,
    unitName: 'Liter',
    estimatedUnitPriceCents: 149,
    totalEstimatedPriceCents: 149,
    selectedStore: 'REWE',
    checked: false,
    automaticallyAdded: false,
    createdAt: new Date().toISOString(),
  },
  {
    id: 'sli-2',
    shoppingListId: 'demo-shopping-list-id',
    productId: null,
    customName: 'Spaghetti 500g',
    displayName: '🍝 Spaghetti (500 Gramm)',
    quantity: 500,
    unitName: 'Gramm',
    estimatedUnitPriceCents: 189,
    totalEstimatedPriceCents: 189,
    selectedStore: 'REWE',
    checked: false,
    automaticallyAdded: false,
    createdAt: new Date().toISOString(),
  },
];

export async function GET(request: NextRequest) {
  return NextResponse.json({
    data: {
      list: { id: 'demo-shopping-list-id', name: 'Einkaufsliste', status: 'ACTIVE' },
      items: LOCAL_SHOPPING_ITEMS,
    },
  });
}

export async function POST(request: NextRequest) {
  const requestId = crypto.randomUUID();
  try {
    const body = await request.json();
    const parsed = addItemSchema.safeParse(body);
    if (!parsed.success) {
      return NextResponse.json(
        { error: { code: 'VALIDATION_ERROR', message: 'Ungültige Eingabedaten.', requestId } },
        { status: 400 }
      );
    }

    const newItem: LocalShoppingItem = {
      id: crypto.randomUUID(),
      shoppingListId: 'demo-shopping-list-id',
      productId: parsed.data.productId || null,
      customName: parsed.data.customName || 'Neuer Artikel',
      displayName: `${parsed.data.customName || 'Neuer Artikel'} (${parsed.data.quantity} ${parsed.data.unitId || 'Stk.'})`,
      quantity: parsed.data.quantity,
      unitName: parsed.data.unitId || 'Stk.',
      estimatedUnitPriceCents: parsed.data.estimatedUnitPriceCents || 149,
      totalEstimatedPriceCents: (parsed.data.estimatedUnitPriceCents || 149) * parsed.data.quantity,
      selectedStore: parsed.data.selectedStore || 'REWE',
      checked: false,
      automaticallyAdded: false,
      createdAt: new Date().toISOString(),
    };

    LOCAL_SHOPPING_ITEMS.unshift(newItem);

    return NextResponse.json({ data: newItem }, { status: 201 });
  } catch (err: any) {
    return NextResponse.json(
      { error: { code: 'SERVER_ERROR', message: err.message, requestId } },
      { status: 500 }
    );
  }
}

export async function DELETE(request: NextRequest) {
  const { searchParams } = new URL(request.url);
  const id = searchParams.get('id');
  if (id) {
    LOCAL_SHOPPING_ITEMS = LOCAL_SHOPPING_ITEMS.filter(i => i.id !== id);
  }
  return NextResponse.json({ success: true });
}