From 0334f7c8839a7fdf6a30c868a638df61278af3ec Mon Sep 17 00:00:00 2001
From: Chirag Chhatrala <60499540+chiragchhatrala@users.noreply.github.com>
Date: Tue, 25 Jun 2024 19:18:20 +0530
Subject: [PATCH] Undo/redo form editor (#452)

* Undo/redo form editor

* Fix undo/redo

* Fix history with version check

* Increase default history size

---------

Co-authored-by: Julien Nahum <julien@nahum.net>
---
 client/components/open/editors/UndoRedo.vue   |  32 ++++
 .../open/forms/components/FormEditor.vue      |   5 +
 client/nuxt.config.ts                         |   3 +
 client/package-lock.json                      |  18 ++
 client/package.json                           |   2 +
 client/plugins/pinia-history.js               | 156 ++++++++++++++++++
 client/stores/working_form.js                 |   1 +
 7 files changed, 217 insertions(+)
 create mode 100644 client/components/open/editors/UndoRedo.vue
 create mode 100644 client/plugins/pinia-history.js

diff --git a/client/components/open/editors/UndoRedo.vue b/client/components/open/editors/UndoRedo.vue
new file mode 100644
index 00000000..ac5d8abb
--- /dev/null
+++ b/client/components/open/editors/UndoRedo.vue
@@ -0,0 +1,32 @@
+<template>
+  <UButtonGroup
+    size="sm"
+    orientation="horizontal"
+  >
+    <UButton
+      :disabled="!canUndo"
+      color="white"
+      icon="i-material-symbols-undo"
+      class="disabled:text-gray-500"
+      @click="undo"
+    />
+    <UButton
+      :disabled="!canRedo"
+      icon="i-material-symbols-redo"
+      color="white"
+      class="disabled:text-gray-500"
+      @click="redo"
+    />
+  </UButtonGroup>
+</template>
+
+<script setup>
+const workingFormStore = useWorkingFormStore()
+
+const { undo, redo, clearHistory } = workingFormStore
+const { canUndo, canRedo } = storeToRefs(workingFormStore)
+
+onMounted(() => {
+  setTimeout(() => { clearHistory() }, 500)
+})
+</script>
diff --git a/client/components/open/forms/components/FormEditor.vue b/client/components/open/forms/components/FormEditor.vue
index d3bd1ee2..4f2047e7 100644
--- a/client/components/open/forms/components/FormEditor.vue
+++ b/client/components/open/forms/components/FormEditor.vue
@@ -28,6 +28,9 @@
         </svg>
         Go back
       </a>
+
+      <UndoRedo />
+
       <div class="hidden md:flex items-center ml-3">
         <h3 class="font-semibold text-lg max-w-[14rem] truncate text-gray-500">
           {{ form.title }}
@@ -118,6 +121,7 @@
 </template>
 
 <script>
+import UndoRedo from "../../editors/UndoRedo.vue"
 import FormEditorSidebar from "./form-components/FormEditorSidebar.vue"
 import FormErrorModal from "./form-components/FormErrorModal.vue"
 import FormInformation from "./form-components/FormInformation.vue"
@@ -136,6 +140,7 @@ import { captureException } from "@sentry/core"
 export default {
   name: "FormEditor",
   components: {
+    UndoRedo,
     FormEditorSidebar,
     FormEditorPreview,
     FormAboutSubmission,
diff --git a/client/nuxt.config.ts b/client/nuxt.config.ts
index 702771a7..62d50ae8 100644
--- a/client/nuxt.config.ts
+++ b/client/nuxt.config.ts
@@ -69,6 +69,9 @@ export default defineNuxtConfig({
         fallback: 'light',
         classPrefix: '',
     },
+    ui: {
+      icons: ['heroicons','material-symbols'],
+    },
     sitemap,
     runtimeConfig,
     gtm
diff --git a/client/package-lock.json b/client/package-lock.json
index 08f5e165..bd37b570 100644
--- a/client/package-lock.json
+++ b/client/package-lock.json
@@ -9,6 +9,7 @@
       "dependencies": {
         "@codemirror/lang-html": "^6.4.7",
         "@hcaptcha/vue3-hcaptcha": "^1.3.0",
+        "@iconify-json/material-symbols": "^1.1.82",
         "@nuxt/ui": "^2.15.0",
         "@pinia/nuxt": "^0.5.1",
         "@popperjs/core": "^2.11.8",
@@ -28,6 +29,7 @@
         "fuse.js": "^6.4.6",
         "js-sha256": "^0.10.0",
         "libphonenumber-js": "^1.10.44",
+        "lzutf8": "^0.6.3",
         "object-to-formdata": "^4.5.1",
         "pinia": "^2.1.7",
         "prismjs": "^1.24.1",
@@ -1671,6 +1673,14 @@
         "@iconify/types": "*"
       }
     },
+    "node_modules/@iconify-json/material-symbols": {
+      "version": "1.1.82",
+      "resolved": "https://registry.npmjs.org/@iconify-json/material-symbols/-/material-symbols-1.1.82.tgz",
+      "integrity": "sha512-E67LgMFiAbEVF7rE38ulZU6NeXcPvayFF4hUUqt3g33tWrLsDNqEFTSsPt03l34rH5uGGtHIakTqtBlZ+/hRkw==",
+      "dependencies": {
+        "@iconify/types": "*"
+      }
+    },
     "node_modules/@iconify-json/ri": {
       "version": "1.1.20",
       "resolved": "https://registry.npmjs.org/@iconify-json/ri/-/ri-1.1.20.tgz",
@@ -9550,6 +9560,14 @@
         "yallist": "^3.0.2"
       }
     },
+    "node_modules/lzutf8": {
+      "version": "0.6.3",
+      "resolved": "https://registry.npmjs.org/lzutf8/-/lzutf8-0.6.3.tgz",
+      "integrity": "sha512-CAkF9HKrM+XpB0f3DepQ2to2iUEo0zrbh+XgBqgNBc1+k8HMM3u/YSfHI3Dr4GmoTIez2Pr/If1XFl3rU26AwA==",
+      "dependencies": {
+        "readable-stream": "^4.0.0"
+      }
+    },
     "node_modules/magic-string": {
       "version": "0.30.8",
       "resolved": "https://registry.npmjs.org/magic-string/-/magic-string-0.30.8.tgz",
diff --git a/client/package.json b/client/package.json
index 9716e8de..2191552b 100644
--- a/client/package.json
+++ b/client/package.json
@@ -31,6 +31,7 @@
   "dependencies": {
     "@codemirror/lang-html": "^6.4.7",
     "@hcaptcha/vue3-hcaptcha": "^1.3.0",
+    "@iconify-json/material-symbols": "^1.1.82",
     "@nuxt/ui": "^2.15.0",
     "@pinia/nuxt": "^0.5.1",
     "@popperjs/core": "^2.11.8",
@@ -50,6 +51,7 @@
     "fuse.js": "^6.4.6",
     "js-sha256": "^0.10.0",
     "libphonenumber-js": "^1.10.44",
+    "lzutf8": "^0.6.3",
     "object-to-formdata": "^4.5.1",
     "pinia": "^2.1.7",
     "prismjs": "^1.24.1",
diff --git a/client/plugins/pinia-history.js b/client/plugins/pinia-history.js
new file mode 100644
index 00000000..33bd106a
--- /dev/null
+++ b/client/plugins/pinia-history.js
@@ -0,0 +1,156 @@
+import {computed, reactive} from 'vue'
+import {compress, decompress} from 'lzutf8'
+import debounce from 'debounce'
+import {hash} from "~/lib/utils.js"
+
+/**
+ * Merges the user-provided options with the default plugin options.
+ * @param {boolean|object} options - The user's configuration options.
+ * @returns {object} The merged configuration options.
+ */
+function mergeOptions(options) {
+  const defaults = {
+    max: 30,
+    persistent: false,
+    persistentStrategy: {
+      get: function (store, type) {
+        if (typeof localStorage !== 'undefined') {
+          const key = `pinia-history-${store.$id}-${type}`
+          const value = localStorage.getItem(key)
+          return value ? decompress(value, {inputEncoding: 'Base64'}).split(',') : undefined
+        }
+      },
+      set: function (store, type, value) {
+        if (typeof localStorage !== 'undefined') {
+          const key = `pinia-history-${store.$id}-${type}`
+          const string = compress(value.join(','), {outputEncoding: 'Base64'})
+          localStorage.setItem(key, string)
+        }
+      },
+      remove: function (store, type) {
+        if (typeof localStorage !== 'undefined') {
+          const key = `pinia-history-${store.$id}-${type}`
+          localStorage.removeItem(key)
+        }
+      }
+    },
+    debounceWait: 300
+  }
+
+  return {
+    ...defaults,
+    ...(typeof options === 'boolean' ? {} : options)
+  }
+}
+
+/**
+ * Adds undo/redo functionality to a Pinia store.
+ * @param {PiniaPluginContext} context - The context provided by Pinia.
+ */
+const PiniaHistory = (context) => {
+  const {store, options} = context
+  const {history} = options
+
+  if (!history) {
+    return
+  }
+  const mergedOptions = mergeOptions(history)
+  const {max, persistent, persistentStrategy} = mergedOptions
+
+  const $history = reactive({
+    max,
+    persistent,
+    persistentStrategy,
+    done: [],
+    undone: [],
+    current: JSON.stringify(store.$state),
+    trigger: true,
+  })
+
+  const debouncedStoreUpdate = debounce((state) => {
+    if (hash($history.current) === hash(JSON.stringify(state))) { // Not a real change here
+      return
+    }
+    if ($history.done.length >= max) $history.done.shift() // Remove oldest state if needed
+
+    $history.done.push($history.current)
+    $history.undone = [] // Clear redo history on new action
+    $history.current = JSON.stringify(state)
+
+    if (persistent) {
+      persistentStrategy.set(store, 'undo', $history.done)
+      persistentStrategy.set(store, 'redo', $history.undone)
+    }
+  }, mergedOptions.debounceWait)
+
+  store.canUndo = computed(() => $history.done.length > 0)
+  store.canRedo = computed(() => $history.undone.length > 0)
+
+  store.undo = () => {
+    if (!store.canUndo) {
+      return
+    }
+
+    debouncedStoreUpdate.clear()
+    const state = $history.done.pop()
+    if (state === undefined) {
+      return
+    }
+
+    $history.undone.push($history.current) // Save current state for redo
+    $history.trigger = false
+    store.$patch(JSON.parse(state))
+    nextTick(() => {
+      $history.current = state
+      $history.trigger = true
+      if (persistent) {
+        persistentStrategy.set(store, 'undo', $history.done)
+        persistentStrategy.set(store, 'redo', $history.undone)
+      }
+    })
+
+  }
+
+  store.redo = () => {
+    if (!store.canRedo) {
+      return
+    }
+    debouncedStoreUpdate.clear()
+    const state = $history.undone.pop()
+    if (state === undefined) {
+      return
+    }
+
+    $history.done.push($history.current) // Save current state for undo
+    $history.trigger = false
+    store.$patch(JSON.parse(state))
+    nextTick(() => {
+      $history.current = state
+      $history.trigger = true
+      if (persistent) {
+        persistentStrategy.set(store, 'undo', $history.done)
+        persistentStrategy.set(store, 'redo', $history.undone)
+      }
+    })
+  }
+
+  store.clearHistory = () => {
+    $history.done = []
+    $history.undone = []
+    if (persistent) {
+      persistentStrategy.set(store, 'undo', $history.done)
+      persistentStrategy.set(store, 'redo', $history.undone)
+    }
+  }
+
+  store.$subscribe((mutation, state) => {
+    if ($history.trigger) {
+      debouncedStoreUpdate(state)
+    }
+  })
+
+}
+
+export default defineNuxtPlugin(nuxtApp => {
+  nuxtApp.$pinia.use(PiniaHistory)
+})
diff --git a/client/stores/working_form.js b/client/stores/working_form.js
index 8a4b141e..efabbcb2 100644
--- a/client/stores/working_form.js
+++ b/client/stores/working_form.js
@@ -153,4 +153,5 @@ export const useWorkingFormStore = defineStore("working_form", {
       this.content.properties = newFields
     }
   },
+  history: {}
 })