From 07fb5e867c284fe040fe519bdd0fd343cee19291 Mon Sep 17 00:00:00 2001
From: Nolan Lawson <nolan@nolanlawson.com>
Date: Sun, 6 May 2018 16:25:17 -0700
Subject: [PATCH] isolate autosuggestion state (#273)

fixes #261
---
 routes/_actions/autosuggest.js                |  62 +++++++
 routes/_actions/compose.js                    |  22 ---
 routes/_actions/emoji.js                      |  22 ---
 .../compose/ComposeAutosuggest.html           | 153 +++++-------------
 .../compose/ComposeAutosuggestionList.html    |   9 +-
 routes/_components/compose/ComposeInput.html  |  59 ++++---
 .../computations/autosuggestComputations.js   |  56 +++++++
 routes/_store/computations/computations.js    |   2 +
 routes/_store/mixins/autosuggestMixins.js     |  19 +++
 routes/_store/mixins/mixins.js                |   2 +
 .../_store/observers/autosuggestObservers.js  |  42 +++++
 routes/_store/observers/observers.js          |   2 +
 webpack.client.config.js                      |   4 +-
 13 files changed, 271 insertions(+), 183 deletions(-)
 create mode 100644 routes/_actions/autosuggest.js
 create mode 100644 routes/_store/computations/autosuggestComputations.js
 create mode 100644 routes/_store/mixins/autosuggestMixins.js
 create mode 100644 routes/_store/observers/autosuggestObservers.js

diff --git a/routes/_actions/autosuggest.js b/routes/_actions/autosuggest.js
new file mode 100644
index 0000000..43facca
--- /dev/null
+++ b/routes/_actions/autosuggest.js
@@ -0,0 +1,62 @@
+import { store } from '../_store/store'
+
+export async function insertUsername (realm, username, startIndex, endIndex) {
+  let { currentInstance } = store.get()
+  let oldText = store.getComposeData(realm, 'text')
+  let pre = oldText.substring(0, startIndex)
+  let post = oldText.substring(endIndex)
+  let newText = `${pre}@${username} ${post}`
+  store.setComposeData(realm, {text: newText})
+  store.setForAutosuggest(currentInstance, realm, {autosuggestSearchResults: []})
+}
+
+export async function clickSelectedAutosuggestionUsername (realm) {
+  let {
+    composeSelectionStart,
+    autosuggestSearchText,
+    autosuggestSelected,
+    autosuggestSearchResults
+  } = store.get()
+  let account = autosuggestSearchResults[autosuggestSelected]
+  let startIndex = composeSelectionStart - autosuggestSearchText.length
+  let endIndex = composeSelectionStart
+  await insertUsername(realm, account.acct, startIndex, endIndex)
+}
+
+export function insertEmojiAtPosition (realm, emoji, startIndex, endIndex) {
+  let { currentInstance } = store.get()
+  let oldText = store.getComposeData(realm, 'text') || ''
+  let pre = oldText.substring(0, startIndex)
+  let post = oldText.substring(endIndex)
+  let newText = `${pre}:${emoji.shortcode}: ${post}`
+  store.setComposeData(realm, {text: newText})
+  store.setForAutosuggest(currentInstance, realm, {autosuggestSearchResults: []})
+}
+
+export async function clickSelectedAutosuggestionEmoji (realm) {
+  let {
+    composeSelectionStart,
+    autosuggestSearchText,
+    autosuggestSelected,
+    autosuggestSearchResults
+  } = store.get()
+  let emoji = autosuggestSearchResults[autosuggestSelected]
+  let startIndex = composeSelectionStart - autosuggestSearchText.length
+  let endIndex = composeSelectionStart
+  await insertEmojiAtPosition(realm, emoji, startIndex, endIndex)
+}
+
+export function selectAutosuggestItem (item) {
+  let {
+    currentComposeRealm,
+    composeSelectionStart,
+    autosuggestSearchText
+  } = store.get()
+  let startIndex = composeSelectionStart - autosuggestSearchText.length
+  let endIndex = composeSelectionStart
+  if (item.acct) {
+    /* no await */ insertUsername(currentComposeRealm, item.acct, startIndex, endIndex)
+  } else {
+    /* no await */ insertEmojiAtPosition(currentComposeRealm, item, startIndex, endIndex)
+  }
+}
diff --git a/routes/_actions/compose.js b/routes/_actions/compose.js
index 5a763d1..81d432a 100644
--- a/routes/_actions/compose.js
+++ b/routes/_actions/compose.js
@@ -50,28 +50,6 @@ export async function postStatus (realm, text, inReplyToId, mediaIds,
   }
 }
 
-export async function insertUsername (realm, username, startIndex, endIndex) {
-  let oldText = store.getComposeData(realm, 'text')
-  let pre = oldText.substring(0, startIndex)
-  let post = oldText.substring(endIndex)
-  let newText = `${pre}@${username} ${post}`
-  store.setComposeData(realm, {text: newText})
-}
-
-export async function clickSelectedAutosuggestionUsername (realm) {
-  let {
-    composeSelectionStart,
-    composeAutosuggestionSearchText,
-    composeAutosuggestionSelected,
-    composeAutosuggestionSearchResults
-  } = store.get()
-  composeAutosuggestionSelected = composeAutosuggestionSelected || 0
-  let account = composeAutosuggestionSearchResults[composeAutosuggestionSelected]
-  let startIndex = composeSelectionStart - composeAutosuggestionSearchText.length
-  let endIndex = composeSelectionStart
-  await insertUsername(realm, account.acct, startIndex, endIndex)
-}
-
 export function setReplySpoiler (realm, spoiler) {
   let contentWarning = store.getComposeData(realm, 'contentWarning')
   let contentWarningShown = store.getComposeData(realm, 'contentWarningShown')
diff --git a/routes/_actions/emoji.js b/routes/_actions/emoji.js
index d63a6a2..7877bfe 100644
--- a/routes/_actions/emoji.js
+++ b/routes/_actions/emoji.js
@@ -28,25 +28,3 @@ export function insertEmoji (realm, emoji) {
   let newText = `${pre}:${emoji.shortcode}: ${post}`
   store.setComposeData(realm, {text: newText})
 }
-
-export function insertEmojiAtPosition (realm, emoji, startIndex, endIndex) {
-  let oldText = store.getComposeData(realm, 'text') || ''
-  let pre = oldText.substring(0, startIndex)
-  let post = oldText.substring(endIndex)
-  let newText = `${pre}:${emoji.shortcode}: ${post}`
-  store.setComposeData(realm, {text: newText})
-}
-
-export async function clickSelectedAutosuggestionEmoji (realm) {
-  let {
-    composeSelectionStart,
-    composeAutosuggestionSearchText,
-    composeAutosuggestionSelected,
-    composeAutosuggestionSearchResults
-  } = store.get()
-  composeAutosuggestionSelected = composeAutosuggestionSelected || 0
-  let emoji = composeAutosuggestionSearchResults[composeAutosuggestionSelected]
-  let startIndex = composeSelectionStart - composeAutosuggestionSearchText.length
-  let endIndex = composeSelectionStart
-  await insertEmojiAtPosition(realm, emoji, startIndex, endIndex)
-}
diff --git a/routes/_components/compose/ComposeAutosuggest.html b/routes/_components/compose/ComposeAutosuggest.html
index e7c6a9f..b12902b 100644
--- a/routes/_components/compose/ComposeAutosuggest.html
+++ b/routes/_components/compose/ComposeAutosuggest.html
@@ -1,10 +1,10 @@
 <div class="compose-autosuggest {shown ? 'shown' : ''} {realm === 'dialog' ? 'is-dialog' : ''}"
        aria-hidden="true" >
   <ComposeAutosuggestionList
-    items={searchResults}
+    items={autosuggestSearchResults}
     on:click="onClick(event)"
-    {type}
-    {selected}
+    type={autosuggestType}
+    selected={autosuggestSelected}
   />
 </div>
 <style>
@@ -39,134 +39,65 @@
 </style>
 <script>
   import { store } from '../../_store/store'
-  import { insertUsername } from '../../_actions/compose'
-  import { insertEmojiAtPosition } from '../../_actions/emoji'
-  import { scheduleIdleTask } from '../../_utils/scheduleIdleTask'
-  import { once } from '../../_utils/once'
   import ComposeAutosuggestionList from './ComposeAutosuggestionList.html'
-  import {
-    searchAccountsByUsername as searchAccountsByUsernameInDatabase
-  } from '../../_database/accountsAndRelationships'
+  import get from 'lodash-es/get'
+  import { selectAutosuggestItem } from '../../_actions/autosuggest'
   import { observe } from 'svelte-extras'
-
-  const SEARCH_RESULTS_LIMIT = 4
-  const DATABASE_SEARCH_RESULTS_LIMIT = 30
-  const MIN_PREFIX_LENGTH = 1
-  const ACCOUNT_SEARCH_REGEX = new RegExp(`(?:\\s|^)(@\\S{${MIN_PREFIX_LENGTH},})$`)
-  const EMOJI_SEARCH_REGEX = new RegExp(`(?:\\s|^)(:[^:]{${MIN_PREFIX_LENGTH},})$`)
+  import { once } from '../../_utils/once'
 
   export default {
     oncreate () {
-      // perf improves for input responsiveness
-      this.observe('composeSelectionStart', () => {
-        scheduleIdleTask(() => {
-          let { composeSelectionStart } = this.get()
-          this.set({composeSelectionStartDeferred: composeSelectionStart})
-        })
-      })
-      this.observe('composeFocused', (composeFocused) => {
-        let updateFocusedState = () => {
-          scheduleIdleTask(() => {
-            let { composeFocused } = this.get()
-            this.set({composeFocusedDeferred: composeFocused})
-          })
-        }
-
+      this._promiseChain = Promise.resolve()
+      this.observe('shouldBeShown', (shouldBeShown) => {
         // TODO: hack so that when the user clicks the button, and the textarea blurs,
         // we don't immediately hide the dropdown which would cause the click to get lost
-        if (composeFocused) {
-          updateFocusedState()
-        } else {
-          Promise.race([
-            new Promise(resolve => setTimeout(resolve, 200)),
-            new Promise(resolve => this.once('autosuggestItemSelected', resolve))
-          ]).then(updateFocusedState)
-        }
-      })
-      this.observe('searchText', async searchText => {
-        let { thisComposeFocused } = this.get()
-        if (!thisComposeFocused || !searchText) {
-          return
-        }
-        let type = searchText.startsWith('@') ? 'account' : 'emoji'
-        let results = (type === 'account')
-          ? await this.searchAccounts(searchText)
-          : await this.searchEmoji(searchText)
-        this.store.set({
-          composeAutosuggestionSelected: 0,
-          composeAutosuggestionSearchText: searchText,
-          composeAutosuggestionSearchResults: results,
-          composeAutosuggestionType: type
+        this._promiseChain = this._promiseChain.then(() => {
+          if (!shouldBeShown) {
+            return Promise.race([
+              new Promise(resolve => setTimeout(resolve, 200)),
+              new Promise(resolve => this.once('autosuggestItemSelected', resolve))
+            ])
+          }
+        }).then(() => {
+          this.set({shown: shouldBeShown})
         })
       })
-      this.observe('shown', shown => {
-        let { thisComposeFocused } = this.get()
-        if (!thisComposeFocused) {
-          return
-        }
-        this.store.set({composeAutosuggestionShown: shown})
-      })
     },
     methods: {
       observe,
       once,
       onClick (item) {
         this.fire('autosuggestItemSelected')
-        let { realm } = this.get()
-        let { composeSelectionStart, composeAutosuggestionSearchText } = this.store.get()
-        let startIndex = composeSelectionStart - composeAutosuggestionSearchText.length
-        let endIndex = composeSelectionStart
-        if (item.acct) {
-          /* no await */ insertUsername(realm, item.acct, startIndex, endIndex)
-        } else {
-          /* no await */ insertEmojiAtPosition(realm, item, startIndex, endIndex)
-        }
-      },
-      async searchAccounts (searchText) {
-        searchText = searchText.substring(1)
-        let { currentInstance } = this.store.get()
-        let results = await searchAccountsByUsernameInDatabase(
-          currentInstance, searchText, DATABASE_SEARCH_RESULTS_LIMIT)
-        return results.slice(0, SEARCH_RESULTS_LIMIT)
-      },
-      searchEmoji (searchText) {
-        searchText = searchText.toLowerCase().substring(1)
-        let { currentCustomEmoji } = this.store.get()
-        let results = currentCustomEmoji.filter(emoji => emoji.shortcode.toLowerCase().startsWith(searchText))
-          .sort((a, b) => a.shortcode.toLowerCase() < b.shortcode.toLowerCase() ? -1 : 1)
-          .slice(0, SEARCH_RESULTS_LIMIT)
-        return results
+        selectAutosuggestItem(item)
       }
     },
     computed: {
-      composeSelectionStart: ({ $composeSelectionStart }) => $composeSelectionStart,
-      composeFocused: ({ $composeFocused }) => $composeFocused,
-      thisComposeFocused: ({ composeFocusedDeferred, realm }) => composeFocusedDeferred === realm,
-      searchResults: ({ $composeAutosuggestionSearchResults }) => $composeAutosuggestionSearchResults || [],
-      type: ({ $composeAutosuggestionType }) => $composeAutosuggestionType || 'account',
-      selected: ({ $composeAutosuggestionSelected }) => $composeAutosuggestionSelected || 0,
-      searchText: ({ text, composeSelectionStartDeferred, thisComposeFocused }) => {
-        if (!thisComposeFocused) {
-          return
-        }
-        let selectionStart = composeSelectionStartDeferred
-        if (!text || selectionStart < MIN_PREFIX_LENGTH) {
-          return
-        }
-
-        let textUpToCursor = text.substring(0, selectionStart)
-        let match = textUpToCursor.match(ACCOUNT_SEARCH_REGEX) || textUpToCursor.match(EMOJI_SEARCH_REGEX)
-        return match && match[1]
-      },
-      shown: ({ thisComposeFocused, searchText, searchResults }) => {
-        return !!(thisComposeFocused &&
-          searchText &&
-          searchResults.length)
-      }
+      /* eslint-disable camelcase */
+      composeSelectionStart: ({ $autosuggestData_composeSelectionStart, $currentInstance, realm }) => (
+        get($autosuggestData_composeSelectionStart, [$currentInstance, realm], 0)
+      ),
+      composeFocused: ({ $autosuggestData_composeFocused, $currentInstance, realm }) => (
+        get($autosuggestData_composeFocused, [$currentInstance, realm], false)
+      ),
+      autosuggestSearchResults: ({ $autosuggestData_autosuggestSearchResults, $currentInstance, realm }) => (
+        get($autosuggestData_autosuggestSearchResults, [$currentInstance, realm], [])
+      ),
+      autosuggestType: ({ $autosuggestData_autosuggestType, $currentInstance, realm }) => (
+        get($autosuggestData_autosuggestType, [$currentInstance, realm])
+      ),
+      autosuggestSelected: ({ $autosuggestData_autosuggestSelected, $currentInstance, realm }) => (
+        get($autosuggestData_autosuggestSelected, [$currentInstance, realm], 0)
+      ),
+      autosuggestSearchText: ({ $autosuggestData_autosuggestSelected, $currentInstance, realm }) => (
+        get($autosuggestData_autosuggestSelected, [$currentInstance, realm])
+      ),
+      /* eslint-enable camelcase */
+      shouldBeShown: ({ realm, $autosuggestShown, composeFocused }) => (
+        !!($autosuggestShown && composeFocused)
+      )
     },
     data: () => ({
-      composeFocusedDeferred: void 0,
-      composeSelectionStartDeferred: 0
+      shown: false
     }),
     store: () => store,
     components: {
diff --git a/routes/_components/compose/ComposeAutosuggestionList.html b/routes/_components/compose/ComposeAutosuggestionList.html
index 5f54206..488526d 100644
--- a/routes/_components/compose/ComposeAutosuggestionList.html
+++ b/routes/_components/compose/ComposeAutosuggestionList.html
@@ -3,7 +3,7 @@
   <li class="compose-autosuggest-list-item">
     <button class="compose-autosuggest-list-button {i === selected ? 'selected' : ''}"
             tabindex="0"
-            on:click="fire('click', item)">
+            on:click="onClick(event, item)">
       <div class="compose-autosuggest-list-grid">
         {#if type === 'account'}
         <Avatar
@@ -102,6 +102,13 @@
 
   export default {
     store: () => store,
+    methods: {
+      onClick (event, item) {
+        event.preventDefault()
+        event.stopPropagation()
+        this.fire('click', item)
+      }
+    },
     components: {
       Avatar
     }
diff --git a/routes/_components/compose/ComposeInput.html b/routes/_components/compose/ComposeInput.html
index 68a535f..538a2b1 100644
--- a/routes/_components/compose/ComposeInput.html
+++ b/routes/_components/compose/ComposeInput.html
@@ -33,8 +33,10 @@
   import debounce from 'lodash-es/debounce'
   import { mark, stop } from '../../_utils/marks'
   import { selectionChange } from '../../_utils/events'
-  import { clickSelectedAutosuggestionUsername } from '../../_actions/compose'
-  import { clickSelectedAutosuggestionEmoji } from '../../_actions/emoji'
+  import {
+    clickSelectedAutosuggestionUsername,
+    clickSelectedAutosuggestionEmoji
+  } from '../../_actions/autosuggest'
   import { observe } from 'svelte-extras'
 
   export default {
@@ -95,14 +97,21 @@
         stop('autosize.destroy()')
       },
       onBlur () {
-        this.store.set({composeFocused: null})
+        scheduleIdleTask(() => {
+          this.store.setForCurrentAutosuggest({composeFocused: false})
+        })
       },
       onFocus () {
-        let { realm } = this.get()
-        this.store.set({composeFocused: realm})
+        scheduleIdleTask(() => {
+          let {realm} = this.get()
+          this.store.set({currentComposeRealm: realm})
+          this.store.setForCurrentAutosuggest({composeFocused: true})
+        })
       },
       onSelectionChange (selectionStart) {
-        this.store.set({composeSelectionStart: selectionStart})
+        scheduleIdleTask(() => {
+          this.store.setForCurrentAutosuggest({composeSelectionStart: selectionStart})
+        })
       },
       onKeydown (e) {
         let { keyCode } = e
@@ -132,14 +141,14 @@
       },
       clickSelectedAutosuggestion (event) {
         let {
-          composeAutosuggestionShown,
-          composeAutosuggestionType
+          autosuggestShown,
+          autosuggestType
         } = this.store.get()
-        if (!composeAutosuggestionShown) {
+        if (!autosuggestShown) {
           return false
         }
         let { realm } = this.get()
-        if (composeAutosuggestionType === 'account') {
+        if (autosuggestType === 'account') {
           /* no await */ clickSelectedAutosuggestionUsername(realm)
         } else { // emoji
           /* no await */ clickSelectedAutosuggestionEmoji(realm)
@@ -150,33 +159,31 @@
       },
       incrementAutosuggestSelected (increment, event) {
         let {
-          composeAutosuggestionShown,
-          composeAutosuggestionSelected,
-          composeAutosuggestionSearchResults
+          autosuggestShown,
+          autosuggestSelected,
+          autosuggestSearchResults
         } = this.store.get()
-        if (!composeAutosuggestionShown) {
+        if (!autosuggestShown) {
           return
         }
-        let selected = composeAutosuggestionSelected || 0
-        let searchResults = composeAutosuggestionSearchResults || []
-        selected += increment
-        if (selected >= 0) {
-          selected = selected % searchResults.length
+        autosuggestSelected += increment
+        if (autosuggestSelected >= 0) {
+          autosuggestSelected = autosuggestSelected % autosuggestSearchResults.length
         } else {
-          selected = searchResults.length + selected
+          autosuggestSelected = autosuggestSearchResults.length + autosuggestSelected
         }
-        this.store.set({composeAutosuggestionSelected: selected})
+        this.store.setForCurrentAutosuggest({autosuggestSelected})
         event.preventDefault()
         event.stopPropagation()
       },
       clearAutosuggestions (event) {
-        let { composeAutosuggestionShown } = this.store.get()
-        if (!composeAutosuggestionShown) {
+        let { autosuggestShown } = this.store.get()
+        if (!autosuggestShown) {
           return
         }
-        this.store.set({
-          composeAutosuggestionSearchResults: [],
-          composeAutosuggestionSelected: 0
+        this.store.setForCurrentAutosuggest({
+          autosuggestSearchResults: [],
+          autosuggestSelected: 0
         })
         event.preventDefault()
         event.stopPropagation()
diff --git a/routes/_store/computations/autosuggestComputations.js b/routes/_store/computations/autosuggestComputations.js
new file mode 100644
index 0000000..d1b2910
--- /dev/null
+++ b/routes/_store/computations/autosuggestComputations.js
@@ -0,0 +1,56 @@
+const MIN_PREFIX_LENGTH = 1
+const ACCOUNT_SEARCH_REGEX = new RegExp(`(?:\\s|^)(@\\S{${MIN_PREFIX_LENGTH},})$`)
+const EMOJI_SEARCH_REGEX = new RegExp(`(?:\\s|^)(:[^:]{${MIN_PREFIX_LENGTH},})$`)
+
+function computeForAutosuggest (store, key, defaultValue) {
+  store.compute(key,
+    ['currentInstance', 'currentComposeRealm', `autosuggestData_${key}`],
+    (currentInstance, currentComposeRealm, root) => {
+      let instanceData = root && root[currentInstance]
+      return (currentComposeRealm && instanceData && currentComposeRealm in instanceData) ? instanceData[currentComposeRealm] : defaultValue
+    })
+}
+
+export function autosuggestComputations (store) {
+  computeForAutosuggest(store, 'composeFocused', false)
+  computeForAutosuggest(store, 'composeSelectionStart', 0)
+  computeForAutosuggest(store, 'autosuggestSelected', 0)
+  computeForAutosuggest(store, 'autosuggestSearchResults', [])
+  computeForAutosuggest(store, 'autosuggestType', null)
+
+  store.compute(
+    'currentComposeText',
+    ['currentComposeData', 'currentComposeRealm'],
+    (currentComposeData, currentComposeRealm) => (
+      currentComposeData[currentComposeRealm] && currentComposeData[currentComposeRealm].text) || ''
+  )
+
+  store.compute(
+    'autosuggestSearchText',
+    ['currentComposeText', 'composeSelectionStart'],
+    (currentComposeText, composeSelectionStart) => {
+      let selectionStart = composeSelectionStart
+      if (!currentComposeText || selectionStart < MIN_PREFIX_LENGTH) {
+        return ''
+      }
+
+      let textUpToCursor = currentComposeText.substring(0, selectionStart)
+      let match = textUpToCursor.match(ACCOUNT_SEARCH_REGEX) || textUpToCursor.match(EMOJI_SEARCH_REGEX)
+      return (match && match[1]) || ''
+    }
+  )
+
+  store.compute(
+    'autosuggestNumSearchResults',
+    ['autosuggestSearchResults'],
+    (autosuggestSearchResults) => autosuggestSearchResults.length
+  )
+
+  store.compute(
+    'autosuggestShown',
+    ['composeFocused', 'autosuggestSearchText', 'autosuggestNumSearchResults'],
+    (composeFocused, autosuggestSearchText, autosuggestNumSearchResults) => (
+      !!(composeFocused && autosuggestSearchText && autosuggestNumSearchResults)
+    )
+  )
+}
diff --git a/routes/_store/computations/computations.js b/routes/_store/computations/computations.js
index 9e360bf..d3ba926 100644
--- a/routes/_store/computations/computations.js
+++ b/routes/_store/computations/computations.js
@@ -1,9 +1,11 @@
 import { instanceComputations } from './instanceComputations'
 import { timelineComputations } from './timelineComputations'
 import { navComputations } from './navComputations'
+import { autosuggestComputations } from './autosuggestComputations'
 
 export function computations (store) {
   instanceComputations(store)
   timelineComputations(store)
   navComputations(store)
+  autosuggestComputations(store)
 }
diff --git a/routes/_store/mixins/autosuggestMixins.js b/routes/_store/mixins/autosuggestMixins.js
new file mode 100644
index 0000000..19823bd
--- /dev/null
+++ b/routes/_store/mixins/autosuggestMixins.js
@@ -0,0 +1,19 @@
+export function autosuggestMixins (Store) {
+  Store.prototype.setForAutosuggest = function (instanceName, realm, obj) {
+    let valuesToSet = {}
+    for (let key of Object.keys(obj)) {
+      let rootKey = `autosuggestData_${key}`
+      let root = this.get()[rootKey] || {}
+      let instanceData = root[instanceName] = root[instanceName] || {}
+      instanceData[realm] = obj[key]
+      valuesToSet[rootKey] = root
+    }
+
+    this.set(valuesToSet)
+  }
+
+  Store.prototype.setForCurrentAutosuggest = function (obj) {
+    let { currentInstance, currentComposeRealm } = this.get()
+    this.setForAutosuggest(currentInstance, currentComposeRealm, obj)
+  }
+}
diff --git a/routes/_store/mixins/mixins.js b/routes/_store/mixins/mixins.js
index 47f001d..1c1b923 100644
--- a/routes/_store/mixins/mixins.js
+++ b/routes/_store/mixins/mixins.js
@@ -1,9 +1,11 @@
 import { timelineMixins } from './timelineMixins'
 import { instanceMixins } from './instanceMixins'
 import { statusMixins } from './statusMixins'
+import { autosuggestMixins } from './autosuggestMixins'
 
 export function mixins (Store) {
   instanceMixins(Store)
   timelineMixins(Store)
   statusMixins(Store)
+  autosuggestMixins(Store)
 }
diff --git a/routes/_store/observers/autosuggestObservers.js b/routes/_store/observers/autosuggestObservers.js
new file mode 100644
index 0000000..1598974
--- /dev/null
+++ b/routes/_store/observers/autosuggestObservers.js
@@ -0,0 +1,42 @@
+import {
+  searchAccountsByUsername as searchAccountsByUsernameInDatabase
+} from '../../_database/accountsAndRelationships'
+
+const SEARCH_RESULTS_LIMIT = 4
+const DATABASE_SEARCH_RESULTS_LIMIT = 30
+
+async function searchAccounts (store, searchText) {
+  searchText = searchText.substring(1)
+  let { currentInstance } = store.get()
+  let results = await searchAccountsByUsernameInDatabase(
+    currentInstance, searchText, DATABASE_SEARCH_RESULTS_LIMIT)
+  return results.slice(0, SEARCH_RESULTS_LIMIT)
+}
+
+function searchEmoji (store, searchText) {
+  searchText = searchText.toLowerCase().substring(1)
+  let { currentCustomEmoji } = store.get()
+  let results = currentCustomEmoji.filter(emoji => emoji.shortcode.toLowerCase().startsWith(searchText))
+    .sort((a, b) => a.shortcode.toLowerCase() < b.shortcode.toLowerCase() ? -1 : 1)
+    .slice(0, SEARCH_RESULTS_LIMIT)
+  return results
+}
+
+export function autosuggestObservers (store) {
+  store.observe('autosuggestSearchText', async autosuggestSearchText => {
+    let { composeFocused } = store.get()
+    if (!composeFocused || !autosuggestSearchText) {
+      return
+    }
+    let type = autosuggestSearchText.startsWith('@') ? 'account' : 'emoji'
+    let results = (type === 'account')
+      ? await searchAccounts(store, autosuggestSearchText)
+      : await searchEmoji(store, autosuggestSearchText)
+    store.setForCurrentAutosuggest({
+      autosuggestSelected: 0,
+      autosuggestSearchText: autosuggestSearchText,
+      autosuggestSearchResults: results,
+      autosuggestType: type
+    })
+  })
+}
diff --git a/routes/_store/observers/observers.js b/routes/_store/observers/observers.js
index 304a201..aaa8697 100644
--- a/routes/_store/observers/observers.js
+++ b/routes/_store/observers/observers.js
@@ -3,6 +3,7 @@ import { timelineObservers } from './timelineObservers'
 import { notificationObservers } from './notificationObservers'
 import { onlineObservers } from './onlineObservers'
 import { navObservers } from './navObservers'
+import { autosuggestObservers } from './autosuggestObservers'
 
 export function observers (store) {
   instanceObservers(store)
@@ -10,4 +11,5 @@ export function observers (store) {
   notificationObservers(store)
   onlineObservers(store)
   navObservers(store)
+  autosuggestObservers(store)
 }
diff --git a/webpack.client.config.js b/webpack.client.config.js
index 806dda3..74b04c1 100644
--- a/webpack.client.config.js
+++ b/webpack.client.config.js
@@ -76,7 +76,9 @@ module.exports = {
     }
   },
   plugins: [
-    new LodashModuleReplacementPlugin()
+    new LodashModuleReplacementPlugin({
+      paths: true
+    })
   ].concat(isDev ? [
     new webpack.HotModuleReplacementPlugin({
       requestTimeout: 120000