import { TFunction } from "i18next"
import { DynamicSearchResultItem } from "../../components/search/types"
import type { Keys } from "../../providers/keybind-provider/types"
import { DEFAULT_SEARCH_ENTITIES } from "./default-search-entities"

export type SearchEntityTransform<TItem = any> = (
  item: TItem
) => DynamicSearchResultItem

/**
 * The `t` signature handed to `groupLabel` functions. Intentionally wider than
 * i18next's `TFunction`: custom entities translate with keys the dashboard's
 * typed resources don't know about.
 */
export type SearchLabelTranslator = (
  key: string,
  options?: Record<string, unknown>
) => string

/**
 * A "Jump to" entry for a search entity: a key sequence bound by the admin
 * shell that also appears in the search palette's navigation group.
 */
export type SearchEntityShortcut = {
  keys: Keys
  /**
   * Label for the "Jump to" entry. Falls back to the entity's group label.
   */
  label?: string | ((t: SearchLabelTranslator) => string)
  /**
   * Whether the entry is grouped with the page or the settings shortcuts.
   * Defaults to `pageShortcut`.
   */
  type?: "pageShortcut" | "settingShortcut"
  to: string
}

export type SearchEntityDefinition<TItem = any> = {
  /**
   * Group heading shown in the search palette.
   * - omitted → `t("app.search.groups.<name>")`, falling back to the entity name
   * - string → used as-is (plain label)
   * - function → called with the i18n `t` function
   */
  groupLabel?: string | ((t: SearchLabelTranslator) => string)
  /**
   * Optional "Jump to" navigation entry for the entity's list page. Omit it
   * for entities that have no page of their own (e.g. nested entities).
   */
  shortcut?: SearchEntityShortcut
  /**
   * Maps a result from `/admin/search` to a palette item. Omit it for entries
   * that only contribute a `shortcut`, i.e. pages that are navigable but hold
   * nothing worth matching on (e.g. reservations). Such entries are skipped
   * when the palette decides what to query and which areas to offer.
   */
  transform?: SearchEntityTransform<TItem>
}

/**
 * Seeded with the built-in commerce set when this module is evaluated.
 * Registering an entity requires importing this module, so the defaults are in
 * place before any app or plugin registration runs — regardless of how the app
 * entry was bundled. `defineSearchEntity` replaces in place and
 * `clearSearchEntities` empties the map, with no ordering caveats.
 */
const searchEntities = new Map<string, SearchEntityDefinition>(
  Object.entries(DEFAULT_SEARCH_ENTITIES)
)

let customized = false

/**
 * Registers (or replaces) a searchable entity for the admin global search.
 *
 * Apps and plugins can call this from `src/admin/search-entities.tsx` to add
 * custom entities or override built-in transforms. Use {@link clearSearchEntities}
 * first when replacing the default commerce set entirely.
 *
 * @example
 * ```tsx
 * import { defineSearchEntity } from "@medusajs/dashboard/lib"
 *
 * defineSearchEntity("organization", {
 *   groupLabel: "Organizations",
 *   shortcut: {
 *     keys: { Mac: ["G", "Z"] },
 *     label: "Go to Organizations",
 *     to: "/organizations",
 *   },
 *   transform: (org) => ({
 *     id: org.id,
 *     title: org.name,
 *     subtitle: org.billing_email,
 *     to: `/organizations/${org.id}`,
 *     value: `organization:${org.id}`,
 *   }),
 * })
 * ```
 */
export function defineSearchEntity<TItem = any>(
  name: string,
  definition: SearchEntityDefinition<TItem>
) {
  searchEntities.set(name, definition)
  customized = true
}

/**
 * Removes every registered search entity, including the built-in commerce set.
 * Call before re-registering a custom set when the default entities should not
 * appear in admin search.
 */
export function clearSearchEntities() {
  searchEntities.clear()
  customized = true
}

/**
 * Whether an app or plugin has changed the registry. While untouched, the
 * search UI lets `/admin/search` decide what "all areas" covers (engine-only
 * when the Search Module is enabled) instead of enumerating the defaults.
 */
export function isSearchRegistryCustomized(): boolean {
  return customized
}

export function getSearchEntity(
  name: string
): SearchEntityDefinition | undefined {
  return searchEntities.get(name)
}

/**
 * The entities that can actually be searched, in registration order.
 * Shortcut-only entries are left out — there is nothing to query for them.
 */
export function getSearchEntityNames(): string[] {
  return [...searchEntities.entries()]
    .filter(([, definition]) => !!definition.transform)
    .map(([name]) => name)
}

/**
 * Whether `name` is registered as a searchable entity. False for shortcut-only
 * entries.
 */
export function hasSearchEntity(name: string): boolean {
  return !!searchEntities.get(name)?.transform
}

export function resolveSearchEntityGroupLabel(
  name: string,
  t: TFunction | SearchLabelTranslator
): string {
  const translate = t as SearchLabelTranslator
  const definition = searchEntities.get(name)
  const label = definition?.groupLabel

  if (typeof label === "function") {
    return label(translate)
  }

  if (typeof label === "string") {
    return label
  }

  // Custom entities usually have no translation for the conventional key, so
  // show the entity name rather than the raw key.
  return translate(`app.search.groups.${name}`, { defaultValue: name })
}

/**
 * The "Jump to" entries of every registered entity that declares one, in
 * registration order.
 */
export function getSearchEntityShortcuts(): {
  entity: string
  shortcut: SearchEntityShortcut
}[] {
  return [...searchEntities.entries()]
    .filter(([, definition]) => !!definition.shortcut)
    .map(([entity, definition]) => ({
      entity,
      shortcut: definition.shortcut!,
    }))
}

export function resolveSearchEntityShortcutLabel(
  name: string,
  t: TFunction | SearchLabelTranslator
): string {
  const translate = t as SearchLabelTranslator
  const label = searchEntities.get(name)?.shortcut?.label

  if (typeof label === "function") {
    return label(translate)
  }

  if (typeof label === "string") {
    return label
  }

  return resolveSearchEntityGroupLabel(name, t)
}