From b098e4cb99302c01bbc1b477307bbed3869f4b4f Mon Sep 17 00:00:00 2001
From: Laurynas Gadliauskas <laurynas.gadliauskas@hostinger.com>
Date: Tue, 1 Jun 2021 12:35:56 +0300
Subject: [PATCH] feat: Unsaved changes confirmation (#4)

---
 frontend/src/i18n/en.json           |  1 +
 frontend/src/views/Files.vue        | 28 +++++++++++++++++++++++++++-
 frontend/src/views/files/Editor.vue | 26 ++++++++++++++++++++++----
 3 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/frontend/src/i18n/en.json b/frontend/src/i18n/en.json
index 0181ed4c..d2c51f9f 100644
--- a/frontend/src/i18n/en.json
+++ b/frontend/src/i18n/en.json
@@ -115,6 +115,7 @@
   },
   "permanent": "Permanent",
   "prompts": {
+    "unsavedChanges": "Changes that you made may not be saved. Leave page?",
     "archive": "Archive",
     "archiveMessage": "Choose archive name and format:",
     "unarchive": "Unarchive",
diff --git a/frontend/src/views/Files.vue b/frontend/src/views/Files.vue
index 8f50426d..1808d218 100644
--- a/frontend/src/views/Files.vue
+++ b/frontend/src/views/Files.vue
@@ -5,7 +5,11 @@
     <breadcrumbs base="/files" />
 
     <errors v-if="error" :errorCode="error.message" />
-    <component v-else-if="currentView" :is="currentView"></component>
+    <component
+      v-else-if="currentView"
+      :is="currentView"
+      @changed="setChanged"
+    ></component>
     <div v-else>
       <h2 class="message delayed">
         <div class="spinner">
@@ -47,6 +51,7 @@ export default {
     return {
       error: null,
       width: window.innerWidth,
+      unsavedChanges: false,
     };
   },
   computed: {
@@ -68,6 +73,12 @@ export default {
       }
     },
   },
+  beforeRouteUpdate(to, from, next) {
+    this.verifyRouteChange(next);
+  },
+  beforeRouteLeave(to, from, next) {
+    this.verifyRouteChange(next);
+  },
   created() {
     this.fetchData();
   },
@@ -92,6 +103,21 @@ export default {
     this.$store.commit("updateRequest", {});
   },
   methods: {
+    verifyRouteChange(next) {
+      if (
+        this.currentView === "editor" &&
+        this.unsavedChanges &&
+        !confirm(this.$t("prompts.unsavedChanges"))
+      ) {
+        next(false);
+      } else {
+        this.unsavedChanges = false;
+        next();
+      }
+    },
+    setChanged(value) {
+      this.unsavedChanges = value;
+    },
     ...mapMutations(["setLoading"]),
     async fetchData() {
       // Reset view information.
diff --git a/frontend/src/views/files/Editor.vue b/frontend/src/views/files/Editor.vue
index 519bd886..192a101b 100644
--- a/frontend/src/views/files/Editor.vue
+++ b/frontend/src/views/files/Editor.vue
@@ -44,7 +44,9 @@ export default {
     Breadcrumbs,
   },
   data: function () {
-    return {};
+    return {
+      unsavedChanges: false,
+    };
   },
   computed: {
     ...mapState(["req", "user"]),
@@ -78,10 +80,17 @@ export default {
       return breadcrumbs;
     },
   },
+  watch: {
+    unsavedChanges() {
+      this.$emit("changed", this.unsavedChanges);
+    },
+  },
   created() {
+    window.addEventListener("beforeunload", this.beforeWindowUnload);
     window.addEventListener("keydown", this.keyEvent);
   },
   beforeDestroy() {
+    window.removeEventListener("beforeunload", this.beforeWindowUnload);
     window.removeEventListener("keydown", this.keyEvent);
     this.editor.destroy();
   },
@@ -97,14 +106,18 @@ export default {
       wrap: true,
     });
 
+    this.editor.on("change", () => (this.unsavedChanges = true));
+
     if (theme == "dark") {
       this.editor.setTheme("ace/theme/twilight");
     }
   },
   methods: {
-    back() {
-      let uri = url.removeLastDir(this.$route.path) + "/";
-      this.$router.push({ path: uri });
+    beforeWindowUnload(e) {
+      if (this.unsavedChanges) {
+        e.preventDefault();
+        e.returnValue = "";
+      }
     },
     keyEvent(event) {
       if (!event.ctrlKey && !event.metaKey) {
@@ -121,6 +134,7 @@ export default {
     async save() {
       const button = "save";
       buttons.loading("save");
+      this.unsavedChanges = false;
 
       try {
         await api.put(this.$route.path, this.editor.getValue());
@@ -131,6 +145,10 @@ export default {
       }
     },
     close() {
+      if (this.unsavedChanges && !confirm(this.$t("prompts.unsavedChanges"))) {
+        return;
+      }
+
       this.$store.commit("updateRequest", {});
 
       let uri = url.removeLastDir(this.$route.path) + "/";