import type { Product } from "@/contexts/product-context"
import { customProductBrandConfig, getProductBrand, productBrandLabel } from "@/lib/product-brand"
import { customSuffixCollidesWithBuiltInProduct } from "@/lib/product-routing"
import { isProductRefHidden, type ProductRef } from "@/lib/product-ref"
import { isListedCustomProduct, type CustomProductBrand } from "@/stores/app-store"

export type SwitcherProductEntry = {
  id: Product
  label: string
  scope?: "Schools" | "Sites"
  customIndex?: number
}

/**
 * Built-in rows for the sidebar switcher + Settings → Products list (custom
 * slots expand at runtime).
 *
 * **Exxat One here is the school's app** (`exxat-one-schools`). The site-side
 * `exxat-one-sites` keeps its id, slug, nav, and routes so its links resolve and
 * it can return, but it is deliberately absent from this list: a workspace buys
 * one side of the partnership, and two rows both labelled "Exxat One" would be a
 * coin toss. The v15 store migration moves anyone parked on Sites across.
 */
export const BUILTIN_SWITCHER_PRODUCTS: SwitcherProductEntry[] = [
  { id: "exxat-prism", label: "Clinical Education" },
  { id: "exxat-one-schools", label: "Exxat One" },
  { id: "exxat-curriculum-mapping", label: "Curriculum Mapping" },
  { id: "exxat-compliance", label: "Compliance" },
  { id: "exxat-surveys", label: "Surveys" },
  { id: "exxat-exam-management", label: "Exam Management" },
  { id: "exxat-accreditation", label: "Accreditation" },
  { id: "exxat-student-success", label: "Student & Program Success" },
  { id: "exxat-design-os", label: "Design OS" },
  { id: "exxat-custom", label: "Custom product" },
]

/** Settings product rows — same built-ins minus the custom placeholder slot. */
export const BUILTIN_SETTINGS_PRODUCTS: SwitcherProductEntry[] =
  BUILTIN_SWITCHER_PRODUCTS.filter(entry => entry.id !== "exxat-custom")

/**
 * Resolve the active switcher row. When the store product is not in the
 * filtered list (e.g. a built-in missing from an older hard-coded array),
 * synthesize a row from the store instead of falling back to the first entry.
 */
export function resolveActiveSwitcherEntry(
  visibleProducts: SwitcherProductEntry[],
  product: Product,
  activeCustomIndex: number,
  customProducts: CustomProductBrand[],
  isCurrent: (entry: SwitcherProductEntry) => boolean,
): SwitcherProductEntry {
  const matched = visibleProducts.find(isCurrent)
  if (matched) return matched

  if (product === "exxat-custom") {
    const brand = customProducts[activeCustomIndex]
    return {
      id: "exxat-custom",
      label: brand
        ? productBrandLabel(customProductBrandConfig(brand))
        : "Custom product",
      customIndex: activeCustomIndex,
    }
  }

  const builtin = BUILTIN_SWITCHER_PRODUCTS.find(entry => entry.id === product)
  if (builtin && builtin.id !== "exxat-custom") return builtin

  const brand = getProductBrand(product)
  return { id: product, label: brand?.label ?? product }
}

/**
 * Products the switcher menu does not list.
 *
 * Design OS is the tool this workspace is built *with*, not one of the products
 * it sells, and the switcher now splits its rows into "included in your plan"
 * and "not in your plan yet" — Design OS answers neither question, so it read
 * as a tenth product wherever it landed. It stays reachable from the profile
 * menu, next to the other workspace-level destinations, and it stays in
 * `BUILTIN_SWITCHER_PRODUCTS` so the trigger can still name it while you are
 * in it and Settings can still list it.
 */
const UNLISTED_SWITCHER_PRODUCTS: ReadonlySet<Product> = new Set<Product>([
  "exxat-design-os",
  // Not marketed in the switcher yet. Routes and Settings entries stay so direct
  // URLs and builder demos still resolve.
  "exxat-accreditation",
  "exxat-student-success",
])

/** Built-in rows + listed custom slots for switcher menus (drops slug collisions). */
export function expandSwitcherProducts(
  customProducts: CustomProductBrand[],
  hiddenProducts: ProductRef[],
): SwitcherProductEntry[] {
  return BUILTIN_SWITCHER_PRODUCTS.flatMap((p): SwitcherProductEntry[] => {
    if (p.id !== "exxat-custom") {
      if (UNLISTED_SWITCHER_PRODUCTS.has(p.id)) return []
      const ref: ProductRef = { product: p.id }
      if (isProductRefHidden(ref, hiddenProducts)) return []
      return [p]
    }
    return customProducts.flatMap((cp, customIndex) => {
      if (!isListedCustomProduct(cp)) return []
      if (customSuffixCollidesWithBuiltInProduct(cp.suffix)) return []
      const ref: ProductRef = { product: "exxat-custom", customIndex }
      if (isProductRefHidden(ref, hiddenProducts)) return []
      return [{ ...p, label: productBrandLabel(customProductBrandConfig(cp)), customIndex }]
    })
  })
}