From 429829b7a1762bf51c452eca912a7e8018490012 Mon Sep 17 00:00:00 2001
From: thePR0M3TH3AN <53631862+PR0M3TH3AN@users.noreply.github.com>
Date: Sun, 26 Oct 2025 18:02:53 -0400
Subject: [PATCH] Refactor video modal into domain controllers

---
 js/ui/components/VideoModal.js                | 286 +++---------------
 .../video-modal/commentsController.js         | 141 +++++++++
 .../video-modal/moderationController.js       | 118 ++++++++
 .../video-modal/reactionsController.js        |  76 +++++
 .../video-modal/similarContentController.js   |  73 +++++
 .../video-modal/utils/commentAvatar.js        |  81 +++++
 tests/video-modal-controllers.test.mjs        |  79 +++++
 7 files changed, 609 insertions(+), 245 deletions(-)
 create mode 100644 js/ui/components/video-modal/commentsController.js
 create mode 100644 js/ui/components/video-modal/moderationController.js
 create mode 100644 js/ui/components/video-modal/reactionsController.js
 create mode 100644 js/ui/components/video-modal/similarContentController.js
 create mode 100644 js/ui/components/video-modal/utils/commentAvatar.js
 create mode 100644 tests/video-modal-controllers.test.mjs

diff --git a/js/ui/components/VideoModal.js b/js/ui/components/VideoModal.js
index c13d4295..b0f702ea 100644
--- a/js/ui/components/VideoModal.js
+++ b/js/ui/components/VideoModal.js
@@ -4,6 +4,15 @@ import { createVideoMoreMenuPanel } from "./videoMenuRenderers.js";
 import { attachAmbientBackground } from "../ambientBackground.js";
 import { applyDesignSystemAttributes } from "../../designSystem.js";
 import { devLogger } from "../../utils/logger.js";
+import { CommentsController } from "./video-modal/commentsController.js";
+import { ReactionsController } from "./video-modal/reactionsController.js";
+import { SimilarContentController } from "./video-modal/similarContentController.js";
+import { ModerationController } from "./video-modal/moderationController.js";
+import {
+  normalizeCommentAvatarKey as normalizeCommentAvatarKeyUtil,
+  resolveCommentAvatarAsset as resolveCommentAvatarAssetUtil,
+  registerCommentAvatarFailure as registerCommentAvatarFailureUtil,
+} from "./video-modal/utils/commentAvatar.js";
 import {
   renderTagPillStrip,
   applyTagPreferenceState,
@@ -188,6 +197,11 @@ export class VideoModal {
       canManageBlacklist: false,
     };
 
+    this.commentsController = new CommentsController({ modal: this });
+    this.reactionsController = new ReactionsController({ modal: this });
+    this.similarContentController = new SimilarContentController({ modal: this });
+    this.moderationController = new ModerationController({ modal: this });
+
     this.commentsRoot = null;
     this.commentsContainer = null;
     this.commentsCountLabel = null;
@@ -479,6 +493,11 @@ export class VideoModal {
       );
     }
 
+    this.commentsController.destroy();
+    this.reactionsController.destroy();
+    this.similarContentController.destroy();
+    this.moderationController.destroy();
+
     this.clearSimilarContent({ preservePending: true });
 
     this.playerModal = playerModal;
@@ -486,7 +505,6 @@ export class VideoModal {
     this.modalBackdrop = playerModal.querySelector("[data-dismiss]") || null;
     this.scrollRegion = this.modalPanel || playerModal;
 
-    this.teardownSimilarContentMediaQuery();
     const nextVideoTagsRoot = playerModal.querySelector("#videoTags") || null;
     if (this.videoTagsRoot && this.videoTagsRoot !== nextVideoTagsRoot) {
       this.cleanupVideoTags(this.videoTagsRoot);
@@ -496,26 +514,8 @@ export class VideoModal {
       this.cleanupVideoTags(this.videoTagsRoot);
     }
 
-    const similarHeading =
-      playerModal.querySelector("#playerModalSimilarContentHeading") || null;
-    const similarList =
-      playerModal.querySelector("#playerModalSimilarContentList") || null;
-    const similarSection =
-      similarList?.closest(
-        "[aria-labelledby='playerModalSimilarContentHeading']"
-      ) || similarHeading?.closest(
-        "[aria-labelledby='playerModalSimilarContentHeading']"
-      ) || null;
-    const similarContainer =
-      similarList?.closest(".watch-container") ||
-      similarHeading?.closest(".watch-container") ||
-      similarSection?.closest(".watch-container") ||
-      similarSection ||
-      null;
-
-    this.similarContentHeading = similarHeading;
-    this.similarContentList = similarList;
-    this.similarContentContainer = similarContainer;
+    const { container: similarContainer } =
+      this.similarContentController.initialize({ playerModal }) || {};
 
     const statsContainerCandidate =
       playerModal.querySelector("[data-video-stats-container]") ||
@@ -540,65 +540,12 @@ export class VideoModal {
       statsContainer: statsContainerCandidate,
     });
 
-    this.setupSimilarContentMediaQuery();
-
-    if (similarList && similarList.children.length) {
-      this.toggleSimilarContentVisibility(true);
-    } else {
-      this.toggleSimilarContentVisibility(false);
-    }
-
     const previousTags = Array.isArray(this.videoTagsData)
       ? [...this.videoTagsData]
       : [];
     this.videoTagsData = null;
 
-    this.videoStage = playerModal.querySelector(".video-modal__video") || null;
-    this.moderationOverlay =
-      this.videoStage?.querySelector("[data-moderation-overlay]") || null;
-    this.moderationBadge =
-      this.moderationOverlay?.querySelector("[data-moderation-badge='true']") || null;
-    this.moderationBadgeText =
-      this.moderationOverlay?.querySelector("[data-moderation-text]") || null;
-    if (this.moderationPrimaryButton) {
-      if (this.moderationPrimaryMode === "override") {
-        this.moderationPrimaryButton.removeEventListener(
-          "click",
-          this.handleModerationOverrideClick,
-        );
-      } else if (this.moderationPrimaryMode === "hide") {
-        this.moderationPrimaryButton.removeEventListener(
-          "click",
-          this.handleModerationHideClick,
-        );
-      }
-    }
-    this.moderationActionsContainer =
-      this.moderationOverlay?.querySelector("[data-moderation-actions]") ||
-      this.moderationBadge?.querySelector(".moderation-badge__actions") ||
-      null;
-    const overrideButton =
-      this.moderationActionsContainer?.querySelector(
-        "[data-moderation-action='override']",
-      ) || null;
-    if (overrideButton) {
-      overrideButton.addEventListener(
-        "click",
-        this.handleModerationOverrideClick,
-      );
-      this.moderationPrimaryButton = overrideButton;
-      this.moderationPrimaryMode = "override";
-    } else {
-      this.moderationPrimaryButton = null;
-      this.moderationPrimaryMode = "";
-    }
-    if (this.moderationBlockButton) {
-      this.moderationBlockButton.removeEventListener(
-        "click",
-        this.handleModerationBlockClick,
-      );
-    }
-    this.moderationBlockButton = null;
+    this.moderationController.initialize({ playerModal });
 
     this.modalVideo = playerModal.querySelector("#modalVideo") || null;
     this.modalStatus = playerModal.querySelector("#modalStatus") || null;
@@ -635,22 +582,7 @@ export class VideoModal {
     this.shareBtn = playerModal.querySelector("#shareBtn") || null;
     this.modalZapBtn = playerModal.querySelector("#modalZapBtn") || null;
     this.modalMoreBtn = playerModal.querySelector("#modalMoreBtn") || null;
-    this.reactionButtons["+"] =
-      playerModal.querySelector("#modalLikeBtn") || null;
-    this.reactionButtons["-"] =
-      playerModal.querySelector("#modalDislikeBtn") || null;
-    this.reactionMeter =
-      playerModal.querySelector("[data-reaction-meter]") || null;
-    this.reactionMeterFill =
-      playerModal.querySelector("[data-reaction-meter-fill]") || null;
-    this.reactionMeterLabel =
-      playerModal.querySelector("[data-reaction-meter-label]") || null;
-    this.reactionMeterAssistive =
-      playerModal.querySelector("[data-reaction-meter-sr]") || null;
-    this.reactionCountLabels["+"] =
-      playerModal.querySelector("[data-reaction-like-count]") || null;
-    this.reactionCountLabels["-"] =
-      playerModal.querySelector("[data-reaction-dislike-count]") || null;
+    this.reactionsController.initialize({ playerModal });
 
     this.renderVideoTags(previousTags);
 
@@ -688,90 +620,7 @@ export class VideoModal {
 
     this.refreshActiveVideoModeration({ video: this.activeVideo });
 
-    this.detachCommentEventHandlers();
-
-    const commentsRoot =
-      playerModal.querySelector("[data-comments-root]") || null;
-    this.commentsRoot = commentsRoot;
-    this.commentsContainer = commentsRoot;
-    this.commentsCountLabel =
-      commentsRoot?.querySelector("[data-comments-count]") || null;
-    this.commentsEmptyState =
-      commentsRoot?.querySelector("[data-comments-empty]") || null;
-    this.commentsList =
-      commentsRoot?.querySelector("[data-comments-list]") || null;
-    this.commentsLoadMoreButton =
-      commentsRoot?.querySelector("[data-comments-load-more]") || null;
-    this.commentsDisabledPlaceholder =
-      playerModal.querySelector("[data-comments-disabled-placeholder]") ||
-      commentsRoot?.querySelector("[data-comments-disabled]") ||
-      null;
-    this.commentsComposer =
-      commentsRoot?.querySelector("[data-comments-composer]") || null;
-    this.commentsInput =
-      this.commentsComposer?.querySelector("[data-comments-input]") || null;
-    this.commentsSubmitButton =
-      this.commentsComposer?.querySelector("[data-comments-submit]") || null;
-    this.commentsStatusMessage =
-      this.commentsComposer?.querySelector("[data-comments-status]") ||
-      commentsRoot?.querySelector("[data-comments-status]") ||
-      null;
-    this.commentsCharCount =
-      this.commentsComposer?.querySelector("[data-comments-char-count]") ||
-      null;
-    this.commentComposerHint =
-      this.commentsComposer?.querySelector("#commentComposerHelp") ||
-      this.commentsComposer?.querySelector(".comment-composer__hint") ||
-      this.commentComposerHint ||
-      null;
-
-    if (this.commentComposerHint) {
-      const hintText = this.commentComposerHint.textContent || "";
-      if (hintText) {
-        this.commentComposerDefaultHint = hintText;
-      }
-    }
-    if (this.commentsCharCount) {
-      const countText = this.commentsCharCount.textContent || "";
-      if (countText) {
-        this.commentComposerDefaultCountText = countText;
-      }
-    }
-    if (this.commentsStatusMessage) {
-      const statusText = this.commentsStatusMessage.textContent || "";
-      if (statusText) {
-        this.commentStatusDefaultText = statusText;
-      }
-    }
-    if (this.commentsInput) {
-      const parsedMax = Number(this.commentsInput.maxLength);
-      if (Number.isFinite(parsedMax) && parsedMax > 0) {
-        this.commentComposerMaxLength = parsedMax;
-      }
-    }
-
-    if (this.commentsDisabledPlaceholder) {
-      const disabledText = this.commentsDisabledPlaceholder.textContent || "";
-      if (disabledText) {
-        this.commentsDisabledPlaceholderDefaultText = disabledText;
-      }
-      this.commentsDisabledPlaceholder.setAttribute("hidden", "");
-    }
-    if (this.commentsComposer) {
-      this.commentsComposer.removeAttribute("hidden");
-    }
-
-    this.clearComments();
-    this.resetCommentComposer();
-    this.attachCommentEventHandlers();
-
-    Object.values(this.reactionButtons).forEach((button) => {
-      if (button) {
-        button.addEventListener("click", this.handleReactionClick);
-      }
-    });
-    this.syncReactionButtons();
-    this.updateReactionMeterDisplay();
+    this.commentsController.initialize({ playerModal });
 
     const closeButton = playerModal.querySelector("#closeModal");
     if (closeButton) {
@@ -1773,80 +1622,25 @@ export class VideoModal {
   }
 
   resolveCommentAvatarAsset(pubkey, sanitizedPicture) {
-    const normalizedPubkey = this.normalizeCommentAvatarKey(pubkey);
-    const normalizedSource =
-      typeof sanitizedPicture === "string" && sanitizedPicture
-        ? sanitizedPicture
-        : "";
-
-    if (normalizedSource && this.commentAvatarFailures.has(normalizedSource)) {
-      return { url: this.DEFAULT_PROFILE_AVATAR, source: "" };
-    }
-
-    if (normalizedPubkey && this.commentAvatarCache.has(normalizedPubkey)) {
-      const cached = this.commentAvatarCache.get(normalizedPubkey);
-      if (cached) {
-        const cachedSource =
-          typeof cached.source === "string" ? cached.source : "";
-        const cachedUrl =
-          typeof cached.url === "string" && cached.url
-            ? cached.url
-            : this.DEFAULT_PROFILE_AVATAR;
-
-        if (!normalizedSource) {
-          return { url: cachedUrl, source: cachedSource };
-        }
-
-        if (cachedSource === normalizedSource) {
-          return { url: cachedUrl, source: cachedSource };
-        }
-      }
-    }
-
-    const resolvedUrl = normalizedSource || this.DEFAULT_PROFILE_AVATAR;
-    if (normalizedPubkey) {
-      this.commentAvatarCache.set(normalizedPubkey, {
-        url: resolvedUrl,
-        source: normalizedSource,
-      });
-    }
-
-    return { url: resolvedUrl, source: normalizedSource };
+    return resolveCommentAvatarAssetUtil({
+      cache: this.commentAvatarCache,
+      failures: this.commentAvatarFailures,
+      defaultAvatar: this.DEFAULT_PROFILE_AVATAR,
+      pubkey,
+      sanitizedPicture,
+    });
   }
 
   normalizeCommentAvatarKey(value) {
-    if (typeof value !== "string") {
-      return "";
-    }
-    const trimmed = value.trim();
-    if (!trimmed) {
-      return "";
-    }
-    return trimmed.toLowerCase();
+    return normalizeCommentAvatarKeyUtil(value);
   }
 
   registerCommentAvatarFailure(sourceUrl) {
-    if (typeof sourceUrl !== "string") {
-      return;
-    }
-    const trimmed = sourceUrl.trim();
-    if (!trimmed || trimmed === this.DEFAULT_PROFILE_AVATAR) {
-      return;
-    }
-
-    if (this.commentAvatarFailures.has(trimmed)) {
-      return;
-    }
-
-    this.commentAvatarFailures.add(trimmed);
-
-    this.commentAvatarCache.forEach((entry, key) => {
-      if (entry && entry.source === trimmed) {
-        this.commentAvatarCache.set(key, {
-          url: this.DEFAULT_PROFILE_AVATAR,
-          source: "",
-        });
-      }
+    registerCommentAvatarFailureUtil({
+      cache: this.commentAvatarCache,
+      failures: this.commentAvatarFailures,
+      defaultAvatar: this.DEFAULT_PROFILE_AVATAR,
+      sourceUrl,
     });
   }
 
@@ -2136,8 +1930,10 @@ export class VideoModal {
 
   destroy() {
     this.close();
-    this.detachCommentEventHandlers();
-    this.removeCommentRetryButton();
+    this.commentsController.destroy();
+    this.reactionsController.destroy();
+    this.similarContentController.destroy();
+    this.moderationController.destroy();
     this.invokeCommentTeardown();
 
     if (this.document) {
diff --git a/js/ui/components/video-modal/commentsController.js b/js/ui/components/video-modal/commentsController.js
new file mode 100644
index 00000000..5112e2e6
--- /dev/null
+++ b/js/ui/components/video-modal/commentsController.js
@@ -0,0 +1,141 @@
+export class CommentsController {
+  constructor({ modal } = {}) {
+    this.modal = modal;
+    this.root = null;
+  }
+
+  initialize({ playerModal } = {}) {
+    if (!this.modal) {
+      return;
+    }
+
+    const root = playerModal?.querySelector("[data-comments-root]") || null;
+    this.root = root;
+    this.modal.commentsRoot = root;
+    this.modal.commentsContainer = root;
+    this.modal.commentsCountLabel =
+      root?.querySelector("[data-comments-count]") || null;
+    this.modal.commentsEmptyState =
+      root?.querySelector("[data-comments-empty]") || null;
+    this.modal.commentsList =
+      root?.querySelector("[data-comments-list]") || null;
+    this.modal.commentsLoadMoreButton =
+      root?.querySelector("[data-comments-load-more]") || null;
+    this.modal.commentsDisabledPlaceholder =
+      playerModal?.querySelector("[data-comments-disabled-placeholder]") ||
+      root?.querySelector("[data-comments-disabled]") ||
+      null;
+    this.modal.commentsComposer =
+      root?.querySelector("[data-comments-composer]") || null;
+    this.modal.commentsInput =
+      this.modal.commentsComposer?.querySelector("[data-comments-input]") || null;
+    this.modal.commentsSubmitButton =
+      this.modal.commentsComposer?.querySelector("[data-comments-submit]") || null;
+    this.modal.commentsStatusMessage =
+      this.modal.commentsComposer?.querySelector("[data-comments-status]") ||
+      root?.querySelector("[data-comments-status]") ||
+      null;
+    this.modal.commentsCharCount =
+      this.modal.commentsComposer?.querySelector("[data-comments-char-count]") ||
+      null;
+    this.modal.commentComposerHint =
+      this.modal.commentsComposer?.querySelector("#commentComposerHelp") ||
+      this.modal.commentsComposer?.querySelector(".comment-composer__hint") ||
+      this.modal.commentComposerHint ||
+      null;
+
+    if (this.modal.commentComposerHint) {
+      const hintText = this.modal.commentComposerHint.textContent || "";
+      if (hintText) {
+        this.modal.commentComposerDefaultHint = hintText;
+      }
+    }
+
+    if (this.modal.commentsCharCount) {
+      const countText = this.modal.commentsCharCount.textContent || "";
+      if (countText) {
+        this.modal.commentComposerDefaultCountText = countText;
+      }
+    }
+
+    if (this.modal.commentsStatusMessage) {
+      const statusText = this.modal.commentsStatusMessage.textContent || "";
+      if (statusText) {
+        this.modal.commentStatusDefaultText = statusText;
+      }
+    }
+
+    if (this.modal.commentsInput) {
+      const parsedMax = Number(this.modal.commentsInput.maxLength);
+      if (Number.isFinite(parsedMax) && parsedMax > 0) {
+        this.modal.commentComposerMaxLength = parsedMax;
+      }
+    }
+
+    if (this.modal.commentsDisabledPlaceholder) {
+      const disabledText =
+        this.modal.commentsDisabledPlaceholder.textContent || "";
+      if (disabledText) {
+        this.modal.commentsDisabledPlaceholderDefaultText = disabledText;
+      }
+      this.modal.commentsDisabledPlaceholder.setAttribute("hidden", "");
+    }
+
+    if (this.modal.commentsComposer) {
+      this.modal.commentsComposer.removeAttribute("hidden");
+    }
+
+    this.modal.clearComments();
+    this.modal.resetCommentComposer();
+    this.modal.attachCommentEventHandlers();
+  }
+
+  update(action = {}) {
+    if (!this.modal) {
+      return;
+    }
+    const { type } = action;
+    switch (type) {
+      case "set-visibility":
+        this.modal.setCommentsVisibility(action.visible);
+        break;
+      case "render":
+        this.modal.renderComments(action.snapshot);
+        break;
+      case "set-composer-state":
+        this.modal.setCommentComposerState(action.state);
+        break;
+      case "set-thread-context":
+        this.modal.setCommentThreadContext(action.context);
+        break;
+      case "clear":
+        this.modal.clearComments();
+        break;
+      default:
+        break;
+    }
+  }
+
+  destroy() {
+    if (!this.modal) {
+      return;
+    }
+    this.modal.detachCommentEventHandlers();
+    this.modal.removeCommentRetryButton();
+    this.modal.commentsRoot = null;
+    this.modal.commentsContainer = null;
+    this.modal.commentsCountLabel = null;
+    this.modal.commentsEmptyState = null;
+    this.modal.commentsList = null;
+    this.modal.commentsLoadMoreButton = null;
+    this.modal.commentsDisabledPlaceholder = null;
+    this.modal.commentsComposer = null;
+    this.modal.commentsInput = null;
+    this.modal.commentsSubmitButton = null;
+    this.modal.commentsStatusMessage = null;
+    this.modal.commentsCharCount = null;
+    this.modal.commentComposerHint = null;
+    this.root = null;
+  }
+}
+
diff --git a/js/ui/components/video-modal/moderationController.js b/js/ui/components/video-modal/moderationController.js
new file mode 100644
index 00000000..222ddcd6
--- /dev/null
+++ b/js/ui/components/video-modal/moderationController.js
@@ -0,0 +1,118 @@
+export class ModerationController {
+  constructor({ modal } = {}) {
+    this.modal = modal;
+  }
+
+  initialize({ playerModal } = {}) {
+    if (!this.modal) {
+      return;
+    }
+
+    this.modal.videoStage =
+      playerModal?.querySelector(".video-modal__video") || null;
+    this.modal.moderationOverlay =
+      this.modal.videoStage?.querySelector("[data-moderation-overlay]") || null;
+    this.modal.moderationBadge =
+      this.modal.moderationOverlay?.querySelector(
+        "[data-moderation-badge='true']",
+      ) || null;
+    this.modal.moderationBadgeText =
+      this.modal.moderationOverlay?.querySelector("[data-moderation-text]") ||
+      null;
+
+    this.teardownPrimaryButton();
+    this.modal.moderationActionsContainer =
+      this.modal.moderationOverlay?.querySelector("[data-moderation-actions]") ||
+      this.modal.moderationBadge?.querySelector(".moderation-badge__actions") ||
+      null;
+
+    const overrideButton =
+      this.modal.moderationActionsContainer?.querySelector(
+        "[data-moderation-action='override']",
+      ) || null;
+    if (overrideButton) {
+      overrideButton.addEventListener(
+        "click",
+        this.modal.handleModerationOverrideClick,
+      );
+      this.modal.moderationPrimaryButton = overrideButton;
+      this.modal.moderationPrimaryMode = "override";
+    } else {
+      this.modal.moderationPrimaryButton = null;
+      this.modal.moderationPrimaryMode = "";
+    }
+
+    this.teardownBlockButton();
+    const blockButton =
+      this.modal.moderationActionsContainer?.querySelector(
+        "[data-moderation-action='block']",
+      ) || null;
+    if (blockButton) {
+      blockButton.addEventListener(
+        "click",
+        this.modal.handleModerationBlockClick,
+      );
+      this.modal.moderationBlockButton = blockButton;
+    } else {
+      this.modal.moderationBlockButton = null;
+    }
+  }
+
+  update(action = {}) {
+    if (!this.modal) {
+      return;
+    }
+    const { type } = action;
+    switch (type) {
+      case "set-context":
+        this.modal.refreshActiveVideoModeration?.(action.context);
+        break;
+      case "set-overlay":
+        this.modal.applyModerationOverlay?.(action.overlay);
+        break;
+      default:
+        break;
+    }
+  }
+
+  destroy() {
+    if (!this.modal) {
+      return;
+    }
+    this.teardownPrimaryButton();
+    this.teardownBlockButton();
+    this.modal.moderationOverlay = null;
+    this.modal.moderationBadge = null;
+    this.modal.moderationBadgeText = null;
+    this.modal.moderationActionsContainer = null;
+    this.modal.moderationPrimaryButton = null;
+    this.modal.moderationPrimaryMode = "";
+    this.modal.moderationBlockButton = null;
+  }
+
+  teardownPrimaryButton() {
+    if (!this.modal?.moderationPrimaryButton) {
+      return;
+    }
+    const button = this.modal.moderationPrimaryButton;
+    if (this.modal.moderationPrimaryMode === "override") {
+      button.removeEventListener(
+        "click",
+        this.modal.handleModerationOverrideClick,
+      );
+    } else if (this.modal.moderationPrimaryMode === "hide") {
+      button.removeEventListener("click", this.modal.handleModerationHideClick);
+    }
+  }
+
+  teardownBlockButton() {
+    if (!this.modal?.moderationBlockButton) {
+      return;
+    }
+    this.modal.moderationBlockButton.removeEventListener(
+      "click",
+      this.modal.handleModerationBlockClick,
+    );
+  }
+}
+
diff --git a/js/ui/components/video-modal/reactionsController.js b/js/ui/components/video-modal/reactionsController.js
new file mode 100644
index 00000000..ea4ec8d3
--- /dev/null
+++ b/js/ui/components/video-modal/reactionsController.js
@@ -0,0 +1,76 @@
+export class ReactionsController {
+  constructor({ modal } = {}) {
+    this.modal = modal;
+    this.boundHandler = (event) => {
+      this.modal?.handleReactionClick?.(event);
+    };
+    this.buttons = [];
+  }
+
+  initialize({ playerModal } = {}) {
+    if (!this.modal) {
+      return;
+    }
+
+    const likeButton = playerModal?.querySelector("#modalLikeBtn") || null;
+    const dislikeButton = playerModal?.querySelector("#modalDislikeBtn") || null;
+    this.modal.reactionButtons = { "+": likeButton, "-": dislikeButton };
+    this.modal.reactionMeter =
+      playerModal?.querySelector("[data-reaction-meter]") || null;
+    this.modal.reactionMeterFill =
+      playerModal?.querySelector("[data-reaction-meter-fill]") || null;
+    this.modal.reactionMeterLabel =
+      playerModal?.querySelector("[data-reaction-meter-label]") || null;
+    this.modal.reactionMeterAssistive =
+      playerModal?.querySelector("[data-reaction-meter-sr]") || null;
+    this.modal.reactionCountLabels = {
+      "+": playerModal?.querySelector("[data-reaction-like-count]") || null,
+      "-": playerModal?.querySelector("[data-reaction-dislike-count]") || null,
+    };
+
+    this.buttons = [likeButton, dislikeButton].filter(Boolean);
+    this.buttons.forEach((button) => {
+      button.removeEventListener("click", this.boundHandler);
+      button.addEventListener("click", this.boundHandler);
+    });
+
+    this.modal.syncReactionButtons?.();
+    this.modal.updateReactionMeterDisplay?.();
+  }
+
+  update(action = {}) {
+    if (!this.modal) {
+      return;
+    }
+    const { type } = action;
+    switch (type) {
+      case "set-summary":
+        this.modal.updateReactionSummary?.(action.summary);
+        break;
+      case "set-user-reaction":
+        this.modal.setUserReaction?.(action.reaction);
+        break;
+      case "reset":
+        this.modal.resetReactions?.();
+        break;
+      default:
+        break;
+    }
+  }
+
+  destroy() {
+    this.buttons.forEach((button) => {
+      button.removeEventListener("click", this.boundHandler);
+    });
+    this.buttons = [];
+    if (this.modal) {
+      this.modal.reactionButtons = { "+": null, "-": null };
+      this.modal.reactionMeter = null;
+      this.modal.reactionMeterFill = null;
+      this.modal.reactionMeterLabel = null;
+      this.modal.reactionMeterAssistive = null;
+      this.modal.reactionCountLabels = { "+": null, "-": null };
+    }
+  }
+}
+
diff --git a/js/ui/components/video-modal/similarContentController.js b/js/ui/components/video-modal/similarContentController.js
new file mode 100644
index 00000000..7b207a67
--- /dev/null
+++ b/js/ui/components/video-modal/similarContentController.js
@@ -0,0 +1,73 @@
+export class SimilarContentController {
+  constructor({ modal } = {}) {
+    this.modal = modal;
+  }
+
+  initialize({ playerModal } = {}) {
+    if (!this.modal) {
+      return { container: null, heading: null, list: null };
+    }
+
+    this.modal.teardownSimilarContentMediaQuery?.();
+
+    const heading =
+      playerModal?.querySelector("#playerModalSimilarContentHeading") || null;
+    const list =
+      playerModal?.querySelector("#playerModalSimilarContentList") || null;
+    const section =
+      list?.closest("[aria-labelledby='playerModalSimilarContentHeading']") ||
+      heading?.closest("[aria-labelledby='playerModalSimilarContentHeading']") ||
+      null;
+    const container =
+      list?.closest(".watch-container") ||
+      heading?.closest(".watch-container") ||
+      section?.closest(".watch-container") ||
+      section ||
+      null;
+
+    this.modal.similarContentHeading = heading;
+    this.modal.similarContentList = list;
+    this.modal.similarContentContainer = container;
+
+    this.modal.setupSimilarContentMediaQuery?.();
+
+    if (list && list.children.length) {
+      this.modal.toggleSimilarContentVisibility?.(true);
+    } else {
+      this.modal.toggleSimilarContentVisibility?.(false);
+    }
+
+    return { container, heading, list };
+  }
+
+  update(action = {}) {
+    if (!this.modal) {
+      return;
+    }
+    const { type } = action;
+    switch (type) {
+      case "set-items":
+        this.modal.setSimilarContent?.(action.items, action.options);
+        break;
+      case "set-visibility":
+        this.modal.toggleSimilarContentVisibility?.(action.visible);
+        break;
+      case "clear":
+        this.modal.clearSimilarContent?.(action.options);
+        break;
+      default:
+        break;
+    }
+  }
+
+  destroy() {
+    if (!this.modal) {
+      return;
+    }
+    this.modal.teardownSimilarContentMediaQuery?.();
+    this.modal.similarContentHeading = null;
+    this.modal.similarContentList = null;
+    this.modal.similarContentContainer = null;
+  }
+}
+
diff --git a/js/ui/components/video-modal/utils/commentAvatar.js b/js/ui/components/video-modal/utils/commentAvatar.js
new file mode 100644
index 00000000..234629ea
--- /dev/null
+++ b/js/ui/components/video-modal/utils/commentAvatar.js
@@ -0,0 +1,81 @@
+export function normalizeCommentAvatarKey(value) {
+  if (typeof value !== "string") {
+    return "";
+  }
+  const trimmed = value.trim();
+  if (!trimmed) {
+    return "";
+  }
+  return trimmed.toLowerCase();
+}
+
+export function resolveCommentAvatarAsset({
+  cache,
+  failures,
+  defaultAvatar,
+  pubkey,
+  sanitizedPicture,
+}) {
+  const normalizedPubkey = normalizeCommentAvatarKey(pubkey);
+  const normalizedSource =
+    typeof sanitizedPicture === "string" && sanitizedPicture
+      ? sanitizedPicture
+      : "";
+
+  if (normalizedSource && failures?.has?.(normalizedSource)) {
+    return { url: defaultAvatar, source: "" };
+  }
+
+  if (normalizedPubkey && cache?.has?.(normalizedPubkey)) {
+    const cached = cache.get(normalizedPubkey);
+    if (cached) {
+      const cachedSource =
+        typeof cached.source === "string" ? cached.source : "";
+      const cachedUrl =
+        typeof cached.url === "string" && cached.url
+          ? cached.url
+          : defaultAvatar;
+
+      if (!normalizedSource || cachedSource === normalizedSource) {
+        return { url: cachedUrl, source: cachedSource };
+      }
+    }
+  }
+
+  const resolvedUrl = normalizedSource || defaultAvatar;
+  if (normalizedPubkey && cache) {
+    cache.set(normalizedPubkey, { url: resolvedUrl, source: normalizedSource });
+  }
+
+  return { url: resolvedUrl, source: normalizedSource };
+}
+
+export function registerCommentAvatarFailure({
+  cache,
+  failures,
+  defaultAvatar,
+  sourceUrl,
+}) {
+  if (typeof sourceUrl !== "string") {
+    return;
+  }
+  const trimmed = sourceUrl.trim();
+  if (!trimmed || trimmed === defaultAvatar) {
+    return;
+  }
+
+  if (!failures?.has?.(trimmed)) {
+    failures?.add?.(trimmed);
+  }
+
+  if (!cache?.forEach) {
+    return;
+  }
+
+  cache.forEach((entry, key) => {
+    if (entry && entry.source === trimmed) {
+      cache.set(key, { url: defaultAvatar, source: "" });
+    }
+  });
+}
+
diff --git a/tests/video-modal-controllers.test.mjs b/tests/video-modal-controllers.test.mjs
new file mode 100644
index 00000000..b5849cdf
--- /dev/null
+++ b/tests/video-modal-controllers.test.mjs
@@ -0,0 +1,79 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+
+import { setupModal } from "./video-modal-accessibility.test.mjs";
+
+test("CommentsController lifecycle manages comment references", async (t) => {
+  const { modal, cleanup } = await setupModal();
+  t.after(cleanup);
+
+  assert.ok(modal.commentsRoot, "comments should be initialized after hydrate");
+
+  modal.commentsController.destroy();
+  assert.equal(modal.commentsRoot, null, "destroy should clear comment root");
+
+  modal.commentsController.initialize({ playerModal: modal.getRoot() });
+  assert.ok(modal.commentsRoot, "initialize should restore comment root");
+});
+
+test("ReactionsController delegates reaction updates", async (t) => {
+  const { modal, cleanup } = await setupModal();
+  t.after(cleanup);
+
+  modal.reactionsController.update({ type: "set-user-reaction", reaction: "+" });
+  assert.equal(
+    modal.reactionState.userReaction,
+    "+",
+    "user reaction should be updated via controller",
+  );
+
+  modal.reactionsController.destroy();
+  assert.equal(
+    modal.reactionButtons["+"],
+    null,
+    "destroy should clear reaction button references",
+  );
+});
+
+test("SimilarContentController toggles section visibility", async (t) => {
+  const { modal, cleanup } = await setupModal();
+  t.after(cleanup);
+
+  const container = modal.similarContentContainer;
+  assert.ok(container, "similar content container should exist");
+
+  modal.similarContentController.update({ type: "set-visibility", visible: false });
+  assert.equal(
+    container.hasAttribute("hidden"),
+    true,
+    "controller should hide similar content when requested",
+  );
+
+  modal.similarContentController.update({ type: "set-visibility", visible: true });
+  assert.equal(
+    container.hasAttribute("hidden"),
+    false,
+    "controller should reveal similar content",
+  );
+});
+
+test("ModerationController reset clears moderation overlay references", async (t) => {
+  const { modal, cleanup } = await setupModal();
+  t.after(cleanup);
+
+  assert.ok(modal.moderationOverlay, "moderation overlay should be present");
+
+  modal.moderationController.destroy();
+  assert.equal(
+    modal.moderationOverlay,
+    null,
+    "destroy should clear moderation overlay references",
+  );
+
+  modal.moderationController.initialize({ playerModal: modal.getRoot() });
+  assert.ok(
+    modal.moderationOverlay,
+    "initialize should restore moderation overlay references",
+  );
+});
+