import { NextResponse } from 'next/server'
import { getCatalog } from '@/lib/catalog-cache'
import { readOverrides } from '@/lib/overrides'

export async function GET() {
  try {
    const [{ items, fetchedAt }, overrides] = await Promise.all([
      getCatalog(),
      Promise.resolve(readOverrides()),
    ])

    const withOverrides = items.map((item) => {
      const ov = overrides[item.id] ?? {}
      const toSlug = (n: string) => n.toLowerCase().replace(/[^a-z0-9]+/g, '-').replace(/^-|-$/g, '')

      // Resolve categories (same logic as catalog route)
      const resolvedCats = ov.categoriesOverride?.length
        ? (() => {
            const cats = ov.categoriesOverride!.map(toSlug)
            return {
              categories:     cats,
              categoryLabels: ov.categoriesOverride!,
              category:       cats[0],
              categoryLabel:  ov.categoriesOverride![0],
            }
          })()
        : {
            category:       ov.categoryOverride      ?? item.category,
            categoryLabel:  ov.categoryLabelOverride ?? item.categoryLabel,
            categories:     ov.categoryOverride
              ? [ov.categoryOverride, ...(item.categories ?? [item.category]).slice(1)]
              : (item.categories ?? [item.category]),
            categoryLabels: ov.categoryLabelOverride
              ? [ov.categoryLabelOverride, ...(item.categoryLabels ?? [item.categoryLabel]).slice(1)]
              : (item.categoryLabels ?? [item.categoryLabel]),
          }

      return {
        ...item,
        // Resolved values (what the customer sees)
        hidden:        ov.hidden         ?? false,
        featured:      ov.featured       ?? item.featured ?? false,
        ...resolvedCats,
        sortOrder:     ov.sortOrder      ?? 0,
        showColors:    ov.showColors     != null ? ov.showColors : item.showColors,
        colorMin:      ov.colorMin       ?? item.colorMin,
        colorMax:      ov.colorMax       !== undefined ? ov.colorMax : item.colorMax,
        chromeSurchargePerColor: ov.chromeSurchargePerColor ?? item.chromeSurchargePerColor,
        disabledColors: ov.disabledColors?.length ? ov.disabledColors : item.disabledColors,
        requiresDelivery:       ov.requiresDelivery != null ? ov.requiresDelivery : item.requiresDelivery,
        deliveryBaseOverride:   ov.deliveryBaseOverride   !== undefined ? ov.deliveryBaseOverride   : item.deliveryBaseOverride,
        deliveryPerMileOverride: ov.deliveryPerMileOverride !== undefined ? ov.deliveryPerMileOverride : item.deliveryPerMileOverride,
        description:   ov.descriptionOverride   ?? item.description,
        variations:    item.variations.filter((v) => !(ov.hiddenVariationIds ?? []).includes(v.id)),
        modifiers:     item.modifiers
          .filter((m) => !(ov.hiddenModifierIds ?? []).includes(m.id))
          .map((m) => {
            const minOverride = ov.modifierMinSelected?.[m.id]
            return minOverride !== undefined ? { ...m, minSelected: minOverride } : m
          }),
        // Raw Square values (for admin display)
        _rawCategory:       item.category,
        _rawCategoryLabel:  item.categoryLabel,
        _rawShowColors:     item.showColors,
        _rawVariations:     item.variations,
        _rawModifiers:      item.modifiers,
        _rawDescription:    item.description,
        _override:          ov,
      }
    })

    return NextResponse.json({ items: withOverrides, overrides, fetchedAt })
  } catch (err) {
    console.error('[admin/items] error:', err)
    return NextResponse.json({ error: 'Failed to load catalog' }, { status: 500 })
  }
}