# Card Layout Implementation Plan

> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.

**Goal:** Wrap each old Reddit post in a shadcn-styled card with configurable gap, page background, and independent toggle from badges.

**Architecture:** Add `rt-card` class to each `div.thing.link` via JS, apply card styling via scoped CSS. Convert internal float layout to flexbox. Shared dark mode detection in `settings.js`. Unified MutationObserver in `main.js` for both badge and card processing.

**Tech Stack:** Vanilla JS (IIFE modules on `window.RedditTweaks`), plain CSS, Firefox WebExtension manifest v2.

## Global Constraints

- old.reddit.com only — `www.reddit.com` is out of scope
- No build tools, no frameworks, no npm dependencies
- All CSS values for the card must match shadcn/ui's default neutral theme exactly (see spec `docs/superpowers/specs/2026-08-26-card-layout-design.md` for token table)
- Modules use IIFE pattern and expose API on `window.RedditTweaks`
- Imports at top of file, no inline imports

---

### Task 1: Extract shared utilities to `settings.js`

Move `isDarkMode()` and `getColorPrefix()` from `badges.js` into `settings.js` as shared infrastructure. Add new setting defaults. Update all consumers.

**Files:**
- Modify: `lib/settings.js`
- Modify: `content/tweaks/badges.js`
- Modify: `content/tweaks/color-popover.js`

**Interfaces:**
- Produces: `window.RedditTweaks.isDarkMode(settings)` → `boolean`
- Produces: `window.RedditTweaks.getColorPrefix(settings)` → `"light" | "dark"`
- Produces: New DEFAULTS keys: `badgeLayout` (true), `cardLayout` (true), `cardBackground` ("reddit"), `cardGap` (16)

- [ ] **Step 1: Add dark mode functions and new defaults to `settings.js`**

Add `isDarkMode`, `getColorPrefix`, and new setting keys to `lib/settings.js`. Insert after the `resetSettings` function, before the `window.RedditTweaks` assignment:

```js
function isDarkMode(settings) {
  if (settings.darkMode === "light") return false;
  if (settings.darkMode === "dark") return true;
  return document.body.classList.contains("res-nightmode");
}

function getColorPrefix(settings) {
  return isDarkMode(settings) ? "dark" : "light";
}
```

Add to `DEFAULTS`:

```js
badgeLayout: true,
cardLayout: true,
cardBackground: "reddit",
cardGap: 16,
```

Add to the `window.RedditTweaks` assignment:

```js
window.RedditTweaks.isDarkMode = isDarkMode;
window.RedditTweaks.getColorPrefix = getColorPrefix;
```

- [ ] **Step 2: Update `badges.js` to use shared functions**

In `content/tweaks/badges.js`:

Remove the `isDarkMode` and `getColorPrefix` function definitions (lines 8-17).

Replace all internal calls to `isDarkMode(settings)` with `window.RedditTweaks.isDarkMode(settings)` and `getColorPrefix(settings)` with `window.RedditTweaks.getColorPrefix(settings)`.

Update the exported API — keep `isDarkMode` and `getColorPrefix` as aliases for backward compatibility during this transition, but point them at the shared versions:

```js
window.RedditTweaks.badgeTweak = {
  apply: apply,
  updateColors: updateColors,
  isDarkMode: window.RedditTweaks.isDarkMode,
  getColorPrefix: window.RedditTweaks.getColorPrefix,
};
```

- [ ] **Step 3: Update `color-popover.js` to use shared functions**

In `content/tweaks/color-popover.js`, change the `getHelpers()` function (lines 16-21):

```js
function getHelpers() {
  return {
    isDarkMode: window.RedditTweaks.isDarkMode,
    getColorPrefix: window.RedditTweaks.getColorPrefix,
  };
}
```

- [ ] **Step 4: Verify extension still works**

Load the extension in Firefox (`about:debugging` → Load Temporary Add-on). Navigate to `old.reddit.com`. Verify:
- Badges render with correct colors
- Dark mode detection works (if RES is installed, toggle night mode)
- Color popover opens and displays correct mode
- No console errors

- [ ] **Step 5: Commit**

```bash
git add lib/settings.js content/tweaks/badges.js content/tweaks/color-popover.js
git commit -m "refactor: extract isDarkMode/getColorPrefix to settings.js as shared utilities"
```

---

### Task 2: Badge layout toggle + FOUC CSS rename

Add `badgeLayout` toggle to the popup and gate badge processing behind it. Rename the FOUC CSS class from `rt-enabled` to `rt-badges-enabled`.

**Files:**
- Modify: `content/styles/badges.css`
- Modify: `content/main.js`
- Modify: `popup/popup.html`
- Modify: `popup/popup.js`

**Interfaces:**
- Consumes: `settings.badgeLayout` (boolean, from Task 1 DEFAULTS)
- Produces: `html.rt-badges-enabled` class on `<html>` (replaces `html.rt-enabled`)

- [ ] **Step 1: Rename FOUC selectors in `badges.css`**

In `content/styles/badges.css`, change the FOUC prevention selectors (lines 1-5):

From:
```css
html.rt-enabled .thing.link .tagline .subreddit,
html.rt-enabled .thing.link .flat-list li:has(> .comments) {
  display: none !important;
}
```

To:
```css
html.rt-badges-enabled .thing.link .tagline .subreddit,
html.rt-badges-enabled .thing.link .flat-list li:has(> .comments) {
  display: none !important;
}
```

- [ ] **Step 2: Update `main.js` to gate badges behind `badgeLayout`**

Replace the `init()` function in `content/main.js`:

```js
async function init() {
  const settings = await window.RedditTweaks.loadSettings();
  if (!settings.enabled) return;

  if (settings.badgeLayout) {
    document.documentElement.classList.add("rt-badges-enabled");
    window.RedditTweaks.badgeTweak.apply(settings);
  }

  browser.storage.onChanged.addListener(function (changes) {
    if (
      (changes.enabled && changes.enabled.newValue !== changes.enabled.oldValue) ||
      (changes.badgeLayout && changes.badgeLayout.newValue !== changes.badgeLayout.oldValue)
    ) {
      location.reload();
      return;
    }

    window.RedditTweaks.loadSettings().then(function (updated) {
      if (settings.badgeLayout) {
        window.RedditTweaks.badgeTweak.updateColors(updated);
      }
    });
  });
}
```

- [ ] **Step 3: Add badge toggle to popup HTML**

In `popup/popup.html`, add a badge toggle after the existing enabled checkbox. Change the first section:

```html
<div class="section">
  <label class="toggle-row">
    <span>Enabled</span>
    <input type="checkbox" id="enabled">
  </label>
  <label class="toggle-row">
    <span>Badge layout</span>
    <input type="checkbox" id="badgeLayout">
  </label>
</div>
```

- [ ] **Step 4: Wire badge toggle in `popup.js`**

In `popup/popup.js`, add `badgeLayout` to the `populateControls` function:

```js
document.getElementById("badgeLayout").checked = settings.badgeLayout;
```

Add change listener in `init()`, next to the existing `enabled` listener:

```js
document.getElementById("badgeLayout").addEventListener("change", saveFromControls);
```

Add to `saveFromControls()` — in the settings object construction, add:

```js
badgeLayout: document.getElementById("badgeLayout").checked,
```

- [ ] **Step 5: Verify badge toggle works**

Reload extension. Open popup:
- Badge layout checkbox is checked by default
- Unchecking it and reloading old.reddit.com: original subreddit/comment links are visible, no badges
- Checking it back: badges return after reload
- No console errors

- [ ] **Step 6: Commit**

```bash
git add content/styles/badges.css content/main.js popup/popup.html popup/popup.js
git commit -m "feat: add badgeLayout toggle, rename FOUC class to rt-badges-enabled"
```

---

### Task 3: Create card CSS

Create `content/styles/cards.css` with all card styling per the spec. Add it to the manifest.

**Files:**
- Create: `content/styles/cards.css`
- Modify: `manifest.json`

**Interfaces:**
- Produces: CSS rules scoped under `.rt-card`, `html.rt-card-enabled`, `html.rt-card-bg-shadcn`

- [ ] **Step 1: Create `content/styles/cards.css`**

```css
/* --- Post list container --- */
html.rt-card-enabled #siteTable {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--rt-card-gap, 1rem);
}

html.rt-card-enabled #siteTable > .clearleft {
  display: none;
}

/* --- Card container --- */
.rt-card {
  background: #ffffff;
  color: #0a0a0a;
  border: 1px solid #e5e5e5;
  border-radius: 0.875rem;
  padding: 1.5rem;
  box-shadow: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  transition: border-color 0.15s;
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  width: 100%;
  overflow: hidden;
}

.rt-card:hover {
  border-color: #d4d4d4;
}

/* --- Card internal layout overrides --- */
.rt-card .midcol,
.rt-card .thumbnail {
  float: none;
  flex-shrink: 0;
}

.rt-card .entry {
  flex: 1;
  min-width: 0;
}

.rt-card .clearleft {
  display: none;
}

/* --- Card dark mode --- */
.rt-dark .rt-card {
  background: #171717;
  color: #fafafa;
  border-color: rgba(255, 255, 255, 0.1);
}

.rt-dark .rt-card:hover {
  border-color: rgba(255, 255, 255, 0.18);
}

/* --- Page background override --- */
html.rt-card-bg-shadcn .content[role="main"] {
  background: #f5f5f5;
}

html.rt-card-bg-shadcn.rt-dark .content[role="main"] {
  background: #262626;
}
```

- [ ] **Step 2: Add `cards.css` to `manifest.json`**

In the `content_scripts[0].css` array, add `content/styles/cards.css` after `badges.css`:

```json
"css": ["content/styles/badges.css", "content/styles/cards.css"],
```

- [ ] **Step 3: Verify no parse errors**

Reload extension. Open `old.reddit.com`. No console CSS parse errors. Cards don't render yet (no JS adding the `rt-card` class), but the CSS is loaded.

- [ ] **Step 4: Commit**

```bash
git add content/styles/cards.css manifest.json
git commit -m "feat: add card CSS with shadcn design tokens"
```

---

### Task 4: Create card JS + unified observer

Create the card tweak module. Refactor `main.js` to use a single shared MutationObserver that dispatches to both badge and card processors. Remove the duplicate observer from `badges.js`.

**Files:**
- Create: `content/tweaks/cards.js`
- Modify: `content/tweaks/badges.js`
- Modify: `content/main.js`
- Modify: `manifest.json`

**Interfaces:**
- Consumes: `window.RedditTweaks.isDarkMode(settings)` (from Task 1)
- Consumes: `settings.cardLayout`, `settings.cardBackground`, `settings.cardGap` (from Task 1)
- Produces: `window.RedditTweaks.cardTweak.apply(settings)` — processes posts + applies card classes
- Produces: `window.RedditTweaks.cardTweak.updateSettings(settings)` — live-update gap/background
- Produces: `window.RedditTweaks.cardTweak.processNewPosts(settings)` — process unprocessed posts (called by shared observer)
- Modifies: `window.RedditTweaks.badgeTweak` — adds `processNewPosts(settings)` for shared observer, removes internal observer

- [ ] **Step 1: Create `content/tweaks/cards.js`**

```js
(function () {
  "use strict";

  function processPost(post) {
    if (post.classList.contains("rt-card")) return;
    post.classList.add("rt-card");
  }

  function processPosts() {
    var posts = document.querySelectorAll("div.thing.link:not(.rt-card)");
    for (var i = 0; i < posts.length; i++) {
      processPost(posts[i]);
    }
  }

  function applyDarkMode(settings) {
    if (window.RedditTweaks.isDarkMode(settings)) {
      document.documentElement.classList.add("rt-dark");
    } else {
      document.documentElement.classList.remove("rt-dark");
    }
  }

  function applyBackground(settings) {
    if (settings.cardBackground === "shadcn") {
      document.documentElement.classList.add("rt-card-bg-shadcn");
    } else {
      document.documentElement.classList.remove("rt-card-bg-shadcn");
    }
  }

  function applyGap(settings) {
    var siteTable = document.getElementById("siteTable");
    if (siteTable) {
      siteTable.style.setProperty("--rt-card-gap", settings.cardGap + "px");
    }
  }

  function apply(settings) {
    document.documentElement.classList.add("rt-card-enabled");
    applyDarkMode(settings);
    applyBackground(settings);
    applyGap(settings);
    processPosts();
  }

  function updateSettings(settings) {
    applyDarkMode(settings);
    applyBackground(settings);
    applyGap(settings);
  }

  window.RedditTweaks = window.RedditTweaks || {};
  window.RedditTweaks.cardTweak = {
    apply: apply,
    updateSettings: updateSettings,
    processNewPosts: processPosts,
  };
})();
```

- [ ] **Step 2: Expose `processNewPosts` from `badges.js`, remove both internal observers**

In `content/tweaks/badges.js`:

Remove the `contentObserver` variable declaration (line 4: `let contentObserver = null;`).

Remove the `darkModeObserver` variable declaration (line 5: `let darkModeObserver = null;`).

Remove the `getObserverTarget()` function (lines 106-112).

Remove the `startContentObserver(settings)` function (lines 114-135).

Remove the `startDarkModeObserver()` function (lines 137-149).

Remove both observer calls from the `apply()` function: `startContentObserver(settings)` (line 168) and `startDarkModeObserver()` (line 169).

Add `processNewPosts` to the exported API:

```js
window.RedditTweaks.badgeTweak = {
  apply: apply,
  updateColors: updateColors,
  isDarkMode: window.RedditTweaks.isDarkMode,
  getColorPrefix: window.RedditTweaks.getColorPrefix,
  processNewPosts: processPosts,
};
```

- [ ] **Step 3: Add unified observer to `main.js`**

In `content/main.js`, add shared observer functions before `init()`.

First, the dark mode observer (moved from `badges.js`). This watches for RES night mode toggles and dispatches to both modules:

```js
function startDarkModeObserver(settings) {
  var observer = new MutationObserver(function () {
    if (settings.darkMode === "auto") {
      window.RedditTweaks.loadSettings().then(function (updated) {
        if (settings.badgeLayout) {
          window.RedditTweaks.badgeTweak.updateColors(updated);
        }
        if (settings.cardLayout) {
          window.RedditTweaks.cardTweak.updateSettings(updated);
        }
      });
    }
  });

  observer.observe(document.body, {
    attributes: true,
    attributeFilter: ["class"],
  });
}
```

Then the content observer for new posts:

```js
function startPostObserver(settings) {
  var target =
    document.getElementById("siteTable") ||
    document.querySelector('.content[role="main"]') ||
    document.body;

  var observer = new MutationObserver(function (mutations) {
    var hasNewPosts = false;
    for (var i = 0; i < mutations.length; i++) {
      var added = mutations[i].addedNodes;
      for (var j = 0; j < added.length; j++) {
        var node = added[j];
        if (node.nodeType !== Node.ELEMENT_NODE) continue;
        if ((node.matches && node.matches("div.thing.link")) ||
            (node.querySelector && node.querySelector("div.thing.link"))) {
          hasNewPosts = true;
          break;
        }
      }
      if (hasNewPosts) break;
    }
    if (hasNewPosts) {
      window.RedditTweaks.loadSettings().then(function (updated) {
        if (settings.badgeLayout) {
          window.RedditTweaks.badgeTweak.processNewPosts(updated);
        }
        if (settings.cardLayout) {
          window.RedditTweaks.cardTweak.processNewPosts(updated);
        }
      });
    }
  });

  observer.observe(target, { childList: true, subtree: true });
}
```

Update `init()` to call `cardTweak.apply`, start the shared observer, and observe dark mode changes for cards:

```js
async function init() {
  const settings = await window.RedditTweaks.loadSettings();
  if (!settings.enabled) return;

  if (settings.badgeLayout) {
    document.documentElement.classList.add("rt-badges-enabled");
    window.RedditTweaks.badgeTweak.apply(settings);
  }

  if (settings.cardLayout) {
    window.RedditTweaks.cardTweak.apply(settings);
  }

  if (settings.badgeLayout || settings.cardLayout) {
    startPostObserver(settings);
    startDarkModeObserver(settings);
  }

  browser.storage.onChanged.addListener(function (changes) {
    if (
      (changes.enabled && changes.enabled.newValue !== changes.enabled.oldValue) ||
      (changes.badgeLayout && changes.badgeLayout.newValue !== changes.badgeLayout.oldValue) ||
      (changes.cardLayout && changes.cardLayout.newValue !== changes.cardLayout.oldValue)
    ) {
      location.reload();
      return;
    }

    window.RedditTweaks.loadSettings().then(function (updated) {
      if (settings.badgeLayout) {
        window.RedditTweaks.badgeTweak.updateColors(updated);
      }
      if (settings.cardLayout) {
        window.RedditTweaks.cardTweak.updateSettings(updated);
      }
    });
  });
}
```

- [ ] **Step 4: Add `cards.js` to `manifest.json`**

In the `content_scripts[0].js` array, add `content/tweaks/cards.js` before `main.js`:

```json
"js": [
  "lib/settings.js",
  "content/tweaks/badges.js",
  "content/tweaks/color-picker.js",
  "content/tweaks/color-popover.js",
  "content/tweaks/cards.js",
  "content/main.js"
],
```

Also remove `"*://www.reddit.com/*"` from the `matches` array (out of scope per spec):

```json
"matches": ["*://old.reddit.com/*"],
```

- [ ] **Step 5: Verify cards render**

Reload extension. Navigate to `old.reddit.com`:
- Each post is wrapped in a card: white background, 1px `#e5e5e5` border, 14px rounded corners, subtle shadow
- Posts are separated by 16px gaps
- Vote arrows, thumbnail, and entry are horizontally aligned (no floats)
- Hovering a card darkens the border to `#d4d4d4`
- Badges still render inside cards (if badge layout is enabled)
- No console errors

- [ ] **Step 6: Commit**

```bash
git add content/tweaks/cards.js content/tweaks/badges.js content/main.js manifest.json
git commit -m "feat: add card layout tweak with unified post observer"
```

---

### Task 5: Popup controls for card settings

Add card layout controls to the extension popup: enable toggle, background style dropdown, card spacing dropdown.

**Files:**
- Modify: `popup/popup.html`
- Modify: `popup/popup.js`

**Interfaces:**
- Consumes: `settings.cardLayout`, `settings.cardBackground`, `settings.cardGap` (from Task 1 DEFAULTS)

- [ ] **Step 1: Add card layout section to popup HTML**

In `popup/popup.html`, add this section after the Dark Mode section and before the Light Mode Colors section:

```html
<div class="section">
  <h2>Card Layout</h2>
  <label class="toggle-row">
    <span>Enable card layout</span>
    <input type="checkbox" id="cardLayout">
  </label>
  <label for="cardBackground">Background Style</label>
  <select id="cardBackground">
    <option value="reddit">Reddit Default</option>
    <option value="shadcn">shadcn Style</option>
  </select>
  <label for="cardGap">Card Spacing</label>
  <select id="cardGap">
    <option value="8">8px</option>
    <option value="12">12px</option>
    <option value="16">16px</option>
    <option value="24">24px</option>
    <option value="32">32px</option>
  </select>
</div>
```

- [ ] **Step 2: Wire card controls in `popup.js`**

In `populateControls(settings)`, add:

```js
document.getElementById("cardLayout").checked = settings.cardLayout;
document.getElementById("cardBackground").value = settings.cardBackground;
document.getElementById("cardGap").value = String(settings.cardGap);
```

In `saveFromControls()`, add to the settings object:

```js
cardLayout: document.getElementById("cardLayout").checked,
cardBackground: document.getElementById("cardBackground").value,
cardGap: parseInt(document.getElementById("cardGap").value, 10),
```

In `init()`, add change listeners:

```js
document.getElementById("cardLayout").addEventListener("change", saveFromControls);
document.getElementById("cardBackground").addEventListener("change", saveFromControls);
document.getElementById("cardGap").addEventListener("change", saveFromControls);
```

- [ ] **Step 3: Verify settings work end-to-end**

Reload extension. Open popup:
- Card layout checkbox is checked by default
- Background dropdown shows "Reddit Default"
- Card spacing shows "16px"
- Changing card spacing to "24px": cards on old.reddit.com update gap live (no reload)
- Changing background to "shadcn Style": page background becomes `#f5f5f5` (live)
- Unchecking card layout: page reloads, cards disappear, posts show flat list
- Settings persist after closing and reopening popup
- Settings persist after browser restart

- [ ] **Step 4: Commit**

```bash
git add popup/popup.html popup/popup.js
git commit -m "feat: add card layout controls to extension popup"
```