Fix #4314: Favorite/vote modes give generic error messages.

Refactor tag scripts to fix multiple issues:

* Errors during tag scripting didn't show the actual error message, just
  a generic "There was an error updating post #NNN" message.
* The quick edit form didn't show any error messages at all on failure.
* Thumbnails didn't have all their data attributes properly updated
  after the post was updated.

This changes it so that thumbnails have their html fully replaced after
updating. This has the side effect of removing event handlers bound
directly to the thumbnail. A `danbooru:post-preview-updated` event is
fired in case userscripts need to detect when thumbnails are updated.

app/controllers/posts_controller.rb

@@ -1,6 +1,6 @@
 class PostsController < ApplicationController
   before_action :member_only, :except => [:show, :show_seq, :index, :home, :random]
-  respond_to :html, :xml, :json
+  respond_to :html, :xml, :json, :js
   layout "sidebar"
 
   def index

app/javascript/src/javascripts/post_mode_menu.js

@@ -57,36 +57,21 @@ PostModeMenu.initialize_selector = function() {
 }
 
 PostModeMenu.initialize_preview_link = function() {
-  $(".post-preview a").on("click.danbooru", PostModeMenu.click);
+  $(document).on("click.danbooru", ".post-preview a", PostModeMenu.click);
 }
 
 PostModeMenu.initialize_edit_form = function() {
   $("#quick-edit-div").hide();
-  $("#quick-edit-form input[value=Cancel]").on("click.danbooru", function(e) {
+
+  $(document).on("click.danbooru", "#quick-edit-form button[name=cancel]", function(e) {
     PostModeMenu.close_edit_form();
     e.preventDefault();
   });
 
-  $("#quick-edit-form").on("submit.danbooru", function(e) {
-    $.ajax({
-      type: "put",
-      url: $("#quick-edit-form").attr("action"),
-      data: {
-        post: {
-          tag_string: $("#post_tag_string").val()
-        }
-      },
-      complete: function() {
-        $.rails.enableFormElements($("#quick-edit-form"));
-      },
-      success: function(data) {
-        Post.update_data(data);
-        Utility.notice("Post #" + data.id + " updated");
-        PostModeMenu.close_edit_form();
-      }
-    });
-
+  $(document).on("click.danbooru", "#quick-edit-form input[type=submit]", async function(e) {
     e.preventDefault();
+    let post_id = $("#quick-edit-form").data("post-id");
+    await Post.update(post_id, "quick-edit", { post: { tag_string: $("#post_tag_string").val() }});
   });
 }
 
@@ -140,7 +125,7 @@ PostModeMenu.change = function() {
 PostModeMenu.open_edit = function(post_id) {
   var $post = $("#post_" + post_id);
   $("#quick-edit-div").slideDown("fast");
-  $("#quick-edit-form").attr("action", "/posts/" + post_id + ".json");
+  $("#quick-edit-form").attr("data-post-id", post_id);
   $("#post_tag_string").val($post.data("tags") + " ").focus().selectEnd();
 
   /* Set height of tag edit box to fit content. */

app/javascript/src/javascripts/posts.js.erb

@@ -470,55 +470,31 @@ Post.resize_ugoira_controls = function() {
   $("#seek-slider").css("width", width - 81);
 }
 
-Post.notice_update = function(x) {
-  if (x === "inc") {
-    Post.pending_update_count += 1;
-    Utility.notice("Updating posts (" + Post.pending_update_count + " pending)...", true);
+Post.show_pending_update_notice = function() {
+  if (Post.pending_update_count === 0) {
+    Utility.notice("Posts updated");
   } else {
-    Post.pending_update_count -= 1;
-
-    if (Post.pending_update_count < 1) {
-      Utility.notice("Posts updated");
-    } else {
-      Utility.notice("Updating posts (" + Post.pending_update_count + " pending)...", true);
-    }
-  }
-}
-
-Post.update_data = function(data) {
-  var $post = $("#post_" + data.id);
-  $post.attr("data-tags", data.tag_string);
-  $post.data("rating", data.rating);
-  $post.removeClass("post-status-has-parent post-status-has-children");
-  if (data.parent_id) {
-    $post.addClass("post-status-has-parent");
-  }
-  if (data.has_visible_children) {
-    $post.addClass("post-status-has-children");
+    Utility.notice(`Updating posts (${Post.pending_update_count} pending)...`, true);
   }
 }
 
 Post.tag = function(post_id, tags) {
   const tag_string = (Array.isArray(tags) ? tags.join(" ") : String(tags));
-  Post.update(post_id, { "post[old_tag_string]": "", "post[tag_string]": tag_string });
+  Post.update(post_id, "tag-script", { post: { old_tag_string: "", tag_string: tag_string }});
 }
 
-Post.update = function(post_id, params) {
-  Post.notice_update("inc");
+Post.update = async function(post_id, mode, params) {
+  try {
+    Post.pending_update_count += 1;
+    Post.show_pending_update_notice()
 
-  $.ajax({
-    type: "PUT",
-    url: "/posts/" + post_id + ".json",
-    data: params,
-    success: function(data) {
-      Post.notice_update("dec");
-      Post.update_data(data);
-    },
-    error: function(data) {
-      Post.notice_update("dec");
-      Utility.error(`There was an error updating <a href="/posts/${post_id}">post #${post_id}</a>`);
-    }
-  });
+    await $.ajax({ type: "PUT", url: `/posts/${post_id}.js?mode=${mode}`, data: params });
+
+    Post.pending_update_count -= 1;
+    Post.show_pending_update_notice();
+  } catch(err) {
+    Post.pending_update_count -= 1;
+  }
 }
 
 Post.initialize_saved_searches = function() {

app/views/posts/partials/index/_edit.html.erb

@@ -1,11 +1,9 @@
 <div id="quick-edit-div" style="display: none;">
   <h1>Edit</h1>
 
-  <%= form_tag("/posts", :class => "simple_form", :method => :put, :id => "quick-edit-form") do %>
-    <div class="input">
-      <%= text_area_tag "post[tag_string]", "", :data => { :autocomplete => "tag-edit" } %>
-      <%= submit_tag "Submit" %>
-      <%= submit_tag "Cancel" %>
-    </div>
+  <%= edit_form_for(:post, html: { id: "quick-edit-form" }) do |f| %>
+    <%= f.input :tag_string, label: "Tags", as: :text, input_html: { "data-autocomplete": "tag-edit" } %>
+    <%= f.submit "Submit", data: { disable_with: false } %>
+    <%= f.button :button, "Cancel", name: :cancel, type: :button %>
   <% end %>
 </div>

app/views/posts/update.js.erb

@@ -0,0 +1,14 @@
+var post_id = <%= @post.id %>;
+var $post = $(`#post_${post_id}`);
+
+<% if @post.valid? %>
+  $post.replaceWith("<%= j PostPresenter.preview(@post) %>");
+<% else %>
+  Danbooru.error(`Post #${post_id}: <%= j @post.errors.full_messages.join("; ") %>`);
+<% end %>
+
+<% if @post.valid? && params[:mode] == "quick-edit" %>
+  Danbooru.PostModeMenu.close_edit_form();
+<% end %>
+
+$(document).trigger("danbooru:post-preview-updated", <%= raw @post.to_json %>);