import { defineStore } from 'pinia'
import { ref } from 'vue'
import * as api from '../api/client.js'

export const useFoldersStore = defineStore('folders', () => {
  const folders = ref([])
  const rootFolders = ref([]) // root-level folders for sidebar tree and folder pickers
  const currentFolderId = ref(null)
  const breadcrumb = ref([])
  const loading = ref(false)
  const error = ref(null)
  const treeVersion = ref(0) // bumped on any mutation so sidebar tree can react

  async function fetchFolders(parentId = null) {
    loading.value = true
    error.value = null
    try {
      const data = await api.listFolders(parentId)
      const list = data.items ?? data
      folders.value = list
      if (parentId === null) rootFolders.value = [...list]
    } catch (e) {
      error.value = e.message || 'Failed to load folders'
    } finally {
      loading.value = false
    }
  }

  async function fetchRootFolders() {
    try {
      const data = await api.listFolders(null)
      rootFolders.value = data.items ?? data
    } catch {}
  }

  async function createFolder(name, parentId = null) {
    loading.value = true
    error.value = null
    try {
      const folder = await api.createFolder(name, parentId)
      folders.value.push(folder)
      if (parentId === null) rootFolders.value.push(folder)
      treeVersion.value++
      return folder
    } catch (e) {
      error.value = e.message || 'Failed to create folder'
      throw e
    } finally {
      loading.value = false
    }
  }

  async function renameFolder(folderId, name) {
    loading.value = true
    error.value = null
    try {
      const updated = await api.renameFolder(folderId, name)
      const idx = folders.value.findIndex(f => f.id === folderId)
      if (idx !== -1) folders.value[idx] = updated
      const rootIdx = rootFolders.value.findIndex(f => f.id === folderId)
      if (rootIdx !== -1) rootFolders.value[rootIdx] = updated
      treeVersion.value++
      return updated
    } catch (e) {
      error.value = e.message || 'Failed to rename folder'
      throw e
    } finally {
      loading.value = false
    }
  }

  async function deleteFolder(folderId) {
    loading.value = true
    error.value = null
    try {
      await api.deleteFolder(folderId)
      folders.value = folders.value.filter(f => f.id !== folderId)
      rootFolders.value = rootFolders.value.filter(f => f.id !== folderId)
      treeVersion.value++
    } catch (e) {
      error.value = e.message || 'Failed to delete folder'
      throw e
    } finally {
      loading.value = false
    }
  }

  async function navigateTo(folderId) {
    currentFolderId.value = folderId
    if (folderId != null) {
      try {
        const data = await api.getFolder(folderId)
        breadcrumb.value = data.breadcrumb || []
      } catch (e) {
        breadcrumb.value = []
      }
    } else {
      breadcrumb.value = []
      folders.value = [] // clear stale subfolder list when returning to home
    }
  }

  return { folders, rootFolders, currentFolderId, breadcrumb, loading, error, treeVersion, fetchFolders, fetchRootFolders, createFolder, renameFolder, deleteFolder, navigateTo }
})