import { computed, ref, shallowRef } from 'vue'
import { defineStore } from 'pinia'
import { CollectionObject } from '@ChronoManager/models/collection'
import { EntityObject } from '@ChronoManager/models/entity'
import { EventObject } from '@ChronoManager/models/event'
import { TaskObject } from '@ChronoManager/models/task'
import type { ServiceObject } from '@ChronoManager/models/service'
import { useCollectionsStore } from '@ChronoManager/stores/collectionsStore'
import { useEntitiesStore } from '@ChronoManager/stores/entitiesStore'
import { useServicesStore } from '@ChronoManager/stores/servicesStore'
import { useImportStore } from '@ChronoManager/stores/importStore'
import type { VisibleDateRange } from '@/types'

type ChronoEntityProperties = EventObject | TaskObject

export const useChronoOperationsStore = defineStore('chronoOperationsStore', () => {
  const servicesStore = useServicesStore()
  const collectionsStore = useCollectionsStore()
  const entitiesStore = useEntitiesStore()
  const importStore = useImportStore()

  const loading = ref(false)
  const visibleRange = shallowRef<VisibleDateRange | null>(null)

  const collections = computed(() => collectionsStore.collections)
  const entities = computed(() => entitiesStore.entities)
  const calendars = computed(() => collections.value.filter(
    collection => collection.properties.content?.includes('event'),
  ))
  const taskLists = computed(() => collections.value.filter(
    collection => collection.properties.content?.includes('task'),
  ))
  const events = computed(() => entities.value.filter(
    entity => entity.properties instanceof EventObject,
  ))
  const tasks = computed(() => entities.value.filter(
    entity => entity.properties instanceof TaskObject,
  ))
  const filteredEvents = computed(() => {
    const visibleCalendarIds = calendars.value
      .filter(calendar => calendar.properties.visibility !== false)
      .map(calendar => calendar.identifier)

    return events.value.filter(event => visibleCalendarIds.includes(event.collection))
  })
  const filteredTasks = computed(() => tasks.value)

  function setVisibleRange(range: VisibleDateRange) {
    if (
      visibleRange.value?.startMs === range.startMs
      && visibleRange.value.endMs === range.endMs
    ) {
      return
    }

    visibleRange.value = { ...range }
  }

  function prepareEntityProperties(entity: EntityObject): ChronoEntityProperties {
    const properties = entity.properties as ChronoEntityProperties
    const now = new Date().toISOString()

    properties.modified = now as never
    if (!entity.identifier) {
      properties.created = now as never
    }

    return properties
  }

  async function saveEntity(entity: EntityObject, collection: CollectionObject): Promise<EntityObject> {
    const properties = prepareEntityProperties(entity).toJson()

    return entity.identifier
      ? entitiesStore.update(entity.identifier, properties)
      : entitiesStore.create(collection.identifier, properties)
  }

  async function deleteEntity(entity: EntityObject) {
    await entitiesStore.delete([entity.identifier])
  }

  async function toggleCalendarVisibility(collection: CollectionObject) {
    const updated = collection.clone()
    updated.properties.visibility = collection.properties.visibility === false
    await collectionsStore.update(updated.identifier, updated.properties)
  }

  async function toggleTaskComplete(taskId: string | number) {
    const taskEntity = tasks.value.find(task => task.identifier === taskId)
    if (!taskEntity) return

    const taskData = taskEntity.properties as TaskObject
    const isCompleted = taskData.status === 'completed'
    taskData.status = isCompleted ? 'needs-action' : 'completed'
    taskData.completedOn = isCompleted ? null : new Date().toISOString() as never
    taskData.progress = isCompleted ? null : 100
    taskData.modified = new Date().toISOString() as never

    await entitiesStore.update(taskEntity.identifier, taskData.toJson())
  }

  async function saveCollection(
    collection: CollectionObject,
    service: ServiceObject,
    mode: 'create' | 'edit',
  ) {
    if (mode === 'create') {
      await collectionsStore.create(service.provider, service.identifier || '', collection.properties)
      return
    }

    await collectionsStore.update(collection.identifier, collection.properties)
  }

  async function deleteCollection(collection: CollectionObject) {
    await collectionsStore.delete(collection.identifier)
  }

  async function prepareImport(files: File[], selectedCollection: CollectionObject | null) {
    importStore.removeAllFiles()
    importStore.reset()

    for (const file of files) {
      const id = importStore.addFile({
        name: file.name,
        contents: await file.text(),
        size: file.size,
        type: file.type,
      })
      if (selectedCollection && collections.value.some(
        collection => collection.identifier === selectedCollection.identifier,
      )) {
        importStore.setCollectionForFile(id, selectedCollection.identifier)
      }
    }

    importStore.stage = 'selecting'
  }

  async function finishImport(refresh = false) {
    if (refresh) {
      const targets = new Set<CollectionObject['identifier']>()
      for (const id of importStore.order) {
        const target = importStore.sessions[id]?.targetIdentifier
        if (target) targets.add(target)
      }
      for (const target of targets) await entitiesStore.list([target])
    }

    importStore.removeAllFiles()
    importStore.reset()
  }

  async function initialize() {
    loading.value = true
    try {
      await servicesStore.list()
      await collectionsStore.list()

      const sources = collections.value.map(collection => collection.identifier)
      if (sources.length > 0) await entitiesStore.list(sources)
    } finally {
      loading.value = false
    }
  }

  return {
    loading,
    visibleRange,
    collections,
    entities,
    calendars,
    taskLists,
    events,
    tasks,
    filteredEvents,
    filteredTasks,
    setVisibleRange,
    saveEntity,
    deleteEntity,
    toggleCalendarVisibility,
    toggleTaskComplete,
    saveCollection,
    deleteCollection,
    prepareImport,
    finishImport,
    initialize,
  }
})