/**
 * Collections Store
 */

import { ref, computed, readonly } from 'vue'
import { defineStore } from 'pinia'
import { collectionService } from '../services/collectionService'
import type {
  CollectionIdentifier,
  ServiceIdentifier,
  ListFilter,
  ListSort,
  CollectionMutableProperties,
} from '../types'
import { CollectionObject } from '../models/collection'

export const useCollectionsStore = defineStore('documentsCollectionsStore', () => {
  // State
  const _collections = ref<Record<string, CollectionObject>>({})
  const transceiving = ref(false)

  // Getters
  const count = computed(() => Object.keys(_collections.value).length)
  const has = computed(() => count.value > 0)
  const collections = computed(() => Object.values(_collections.value))

  const collectionsByService = computed(() => {
    const groups: Record<string, CollectionObject[]> = {}

    Object.values(_collections.value).forEach((collection) => {
      const serviceKey = `${collection.provider}:${collection.service}`
      const serviceCollections = (groups[serviceKey] ??= [])
      serviceCollections.push(collection)
    })

    return groups
  })

  function identifierKey(provider: string, service: string | number | null, identifier: string | number | null): string {
    return `${provider}:${service ?? ''}:${identifier ?? ''}`
  }

  function collection(provider: string, service: string | number, identifier: string | number, retrieve: boolean = false): CollectionObject | null {
    const key = identifierKey(provider, service, identifier)
    if (retrieve === true && !_collections.value[key]) {
      console.debug(`[Documents Manager][Store] - Force fetching collection "${key}"`)
      fetch(provider, service, identifier)
    }

    return _collections.value[key] || null
  }

  function collectionsForService(provider: string, service: string | number): CollectionObject[] {
    const serviceKeyPrefix = `${provider}:${service}:`
    return Object.entries(_collections.value)
      .filter(([key]) => key.startsWith(serviceKeyPrefix))
      .map(([_, collectionObj]) => collectionObj)
  }

  function clearService(provider: string, service: string | number): void {
    const serviceKeyPrefix = `${provider}:${service}:`
    Object.keys(_collections.value)
      .filter((key) => key.startsWith(serviceKeyPrefix))
      .forEach((key) => {
        delete _collections.value[key]
      })
  }

  function clearAll(): void {
    _collections.value = {}
  }

  // Actions
  async function list(sources?: (ServiceIdentifier | CollectionIdentifier)[], filter?: ListFilter, sort?: ListSort): Promise<Record<string, CollectionObject>> {
    transceiving.value = true
    try {
      const response = await collectionService.list({ sources, filter, sort })

      const hydrated: Record<string, CollectionObject> = {}
      Object.entries(response).forEach(([providerId, providerServices]) => {
        Object.entries(providerServices).forEach(([serviceId, serviceCollections]) => {
          Object.entries(serviceCollections).forEach(([collectionId, collectionObj]) => {
            const key = identifierKey(providerId, serviceId, collectionId)
            hydrated[key] = collectionObj
          })
        })
      })

      _collections.value = { ..._collections.value, ...hydrated }

      console.debug('[Documents Manager][Store] - Successfully retrieved', Object.keys(hydrated).length, 'collections')
      return hydrated
    } catch (error: any) {
      console.error('[Documents Manager][Store] - Failed to retrieve collections:', error)
      throw error
    } finally {
      transceiving.value = false
    }
  }

  async function fetch(provider: string, service: string | number, identifier: string | number): Promise<CollectionObject> {
    transceiving.value = true
    try {
      const response = await collectionService.fetch({ targets: [`${provider}:${service}:${identifier}`] })
      const key = identifierKey(response.provider, response.service, response.identifier)
      _collections.value[key] = response

      console.debug('[Documents Manager][Store] - Successfully fetched collection:', key)
      return response
    } catch (error: any) {
      console.error('[Documents Manager][Store] - Failed to fetch collection:', error)
      throw error
    } finally {
      transceiving.value = false
    }
  }

  async function extant(targets: CollectionIdentifier[]) {
    transceiving.value = true
    try {
      const response = await collectionService.extant({ targets })
      console.debug('[Documents Manager][Store] - Successfully checked collection availability')
      return response
    } catch (error: any) {
      console.error('[Documents Manager][Store] - Failed to check collection availability:', error)
      throw error
    } finally {
      transceiving.value = false
    }
  }

  async function create(
    provider: string,
    service: string | number,
    collection: string | number | null,
    properties: CollectionMutableProperties,
  ): Promise<CollectionObject> {
    transceiving.value = true
    try {
      const target: CollectionIdentifier | undefined = collection !== null && collection !== undefined && collection !== ''
        ? `${provider}:${service}:${collection}`
        : undefined
      const response = await collectionService.create({ provider, service: String(service), target, properties })
      const key = identifierKey(response.provider, response.service, response.identifier)
      _collections.value[key] = response

      console.debug('[Documents Manager][Store] - Successfully created collection:', key)
      return response
    } catch (error: any) {
      console.error('[Documents Manager][Store] - Failed to create collection:', error)
      throw error
    } finally {
      transceiving.value = false
    }
  }

  async function update(
    provider: string,
    service: string | number,
    identifier: string | number,
    properties: CollectionMutableProperties,
  ): Promise<CollectionObject> {
    transceiving.value = true
    try {
      const response = await collectionService.update({ target: `${provider}:${service}:${identifier}`, properties })
      const key = identifierKey(response.provider, response.service, response.identifier)
      _collections.value[key] = response

      console.debug('[Documents Manager][Store] - Successfully updated collection:', key)
      return response
    } catch (error: any) {
      console.error('[Documents Manager][Store] - Failed to update collection:', error)
      throw error
    } finally {
      transceiving.value = false
    }
  }

  async function remove(provider: string, service: string | number, identifier: string | number): Promise<{ success: boolean }> {
    transceiving.value = true
    try {
      const response = await collectionService.delete({ target: `${provider}:${service}:${identifier}` })
      const success = response.disposition === 'deleted' || response.disposition === 'moved'
      if (success) {
        const key = identifierKey(provider, service, identifier)
        delete _collections.value[key]
      }

      console.debug('[Documents Manager][Store] - Successfully deleted collection:', `${provider}:${service}:${identifier}`)
      return { success }
    } catch (error: any) {
      console.error('[Documents Manager][Store] - Failed to delete collection:', error)
      throw error
    } finally {
      transceiving.value = false
    }
  }

  return {
    transceiving: readonly(transceiving),
    count,
    has,
    collections,
    collectionsByService,
    collection,
    collectionsForService,
    clearService,
    clearAll,
    list,
    fetch,
    extant,
    create,
    update,
    delete: remove,
  }
})