// Adapted from legacy henza_pwa/src/Mixins/favorite.ts + the `favorits` slice of
// myDataStore. Legacy kept favourites on the server (POST add-to-fav /
// get-favorites, table major_favorites); so does this, through
// /customer/me/favorites (FAV-01). It used to be memory-only, so favourites
// vanished on reload and the ones imported from legacy were never shown.
import { defineStore } from 'pinia'
import { ref, watch } from 'vue'
import { api } from '../api/client'
import { useSessionStore } from './session'

export const useFavoritesStore = defineStore('favorites', () => {
  const ids = ref<string[]>([])
  const session = useSessionStore()

  async function load() {
    try {
      ids.value = (await api.getFavorites()).ids
    } catch (e) {
      // Offline or a dead session (the client already handles 401): keep what we have.
      console.warn('favorites: load failed', e)
    }
  }

  // Loaded for whoever is signed in, cleared on logout — never another user's
  // list. `actingAs` is watched alongside the token because «ورود به حساب
  // مشتری» changes whose favourites these are WITHOUT changing the token: a
  // sales expert entering a customer's account would otherwise see their own
  // hearts on the customer's products, and tapping one would write to the
  // customer's list.
  watch(
    () => [session.token, session.actingAs?.id ?? null] as const,
    ([token]) => {
      ids.value = []
      if (token) void load()
    },
    { immediate: true },
  )

  /** Flips at once on screen, then confirms with the server (legacy toggled the same way). */
  async function toggle(id: string) {
    const was = ids.value.includes(id)
    ids.value = was ? ids.value.filter((x) => x !== id) : [id, ...ids.value]
    try {
      const { favorite } = await api.toggleFavorite(id)
      const has = ids.value.includes(id)
      if (favorite && !has) ids.value = [id, ...ids.value]
      if (!favorite && has) ids.value = ids.value.filter((x) => x !== id)
    } catch (e) {
      // Put it back so the heart never shows a state the server does not hold.
      ids.value = was ? [id, ...ids.value.filter((x) => x !== id)] : ids.value.filter((x) => x !== id)
      console.warn('favorites: toggle failed', e)
    }
  }

  function isFavorite(id: string) {
    return ids.value.includes(id)
  }

  return { ids, load, toggle, isFavorite }
})