# Score Ratio Badge 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:** Add a temperature-coded badge to each post showing the score-per-comment ratio, using Font Awesome's fire icon and an HSL color scale from blue (cold) to red (hot).

**Architecture:** New `ratio.js` IIFE module on `window.RedditTweaks.ratioTweak` with the standard tweak interface. Score and comment count are parsed from the DOM per post. HSL hue is computed from the ratio and set as CSS custom properties on each badge element. CSS handles light/dark mode lightness via selectors. Font Awesome solid subset is bundled with scoped CSS to prevent global pollution.

**Tech Stack:** Vanilla JS (IIFE modules on `window.RedditTweaks`), plain CSS with custom properties, Font Awesome 6 Free (solid subset), Firefox WebExtension manifest v2.

## Global Constraints

- old.reddit.com only
- No build tools, no frameworks, no npm runtime dependencies
- Modules use IIFE pattern and expose API on `window.RedditTweaks`
- Imports at top of file, no inline imports
- Score ratio requires `badgeLayout` or `cardLayout` to be enabled (accepted dependency)
- In `main.js`, badges must always process before ratio (hard call-order requirement)
- FA CSS must be scoped under `.rt-badge--ratio` — no global FA selectors
- Design spec: `docs/superpowers/specs/2026-08-27-vote-ratio-badge-design.md`

---

### Task 1: Settings infrastructure + popup toggle

Add the `scoreRatio` setting and wire a toggle in the popup's Card Layout section.

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

**Interfaces:**
- Produces: `settings.scoreRatio` (boolean, default `true`)

- [ ] **Step 1: Add `scoreRatio` to DEFAULTS in `lib/settings.js`**

In `lib/settings.js`, add `scoreRatio: true` to the `DEFAULTS` object, after `cardGap: 16`:

```js
    cardGap: 16,
    scoreRatio: true,
```

- [ ] **Step 2: Add toggle to `popup/popup.html`**

In `popup/popup.html`, inside the Card Layout section, add the score ratio toggle after the "Enable card layout" toggle (after line 40: `</label>`):

```html
      <label class="toggle-row">
        <span>Score ratio badge</span>
        <input type="checkbox" id="scoreRatio">
      </label>
```

- [ ] **Step 3: Wire toggle in `popup/popup.js`**

In `popup/popup.js`, add to `populateControls(settings)`, after the `cardLayout` checkbox line:

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

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

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

In `init()`, add a change listener, after the `cardLayout` listener:

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

- [ ] **Step 4: Verify toggle works**

Load the extension in Firefox (`about:debugging` → Load Temporary Add-on). Open popup:
- "Score ratio badge" checkbox appears in the Card Layout section, checked by default
- Unchecking and reopening popup: stays unchecked (persisted)
- Re-checking: persists
- No console errors

- [ ] **Step 5: Commit**

```bash
git add lib/settings.js popup/popup.html popup/popup.js
git commit -m "feat: add scoreRatio setting and popup toggle"
```

---

### Task 2: Font Awesome solid subset + ratio badge CSS

Download the FA solid woff2 font, create scoped FA CSS and the ratio badge stylesheet, and register both in the manifest.

**Files:**
- Create: `content/fonts/fontawesome/fa-solid-900.woff2` (downloaded)
- Create: `content/styles/fontawesome-scoped.css`
- Create: `content/styles/ratio.css`
- Modify: `manifest.json`

**Interfaces:**
- Produces: `@font-face` for "Font Awesome 6 Free" (solid, weight 900)
- Produces: `.rt-badge--ratio .fa-solid` and `.rt-badge--ratio .fa-fire::before` selectors
- Produces: `.rt-badge--ratio` and `.rt-badge--ratio-neutral` CSS classes consuming `--rt-ratio-hue` and `--rt-ratio-sat` custom properties

- [ ] **Step 1: Download FA 6.7.2 solid woff2 (pinned version)**

```bash
mkdir -p content/fonts/fontawesome
curl -f -L -o content/fonts/fontawesome/fa-solid-900.woff2 \
  "https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.7.2/webfonts/fa-solid-900.woff2"
```

Verify integrity — must be 158KB with sha256 `aa75998623a391e61c6901794ace832e3ecdd288b56d608f21bea0411acc0b8e`:

```bash
ls -lh content/fonts/fontawesome/fa-solid-900.woff2
shasum -a 256 content/fonts/fontawesome/fa-solid-900.woff2
```

If the hash doesn't match or the download fails (curl `-f` flag fails on HTTP errors), stop and investigate — the CDN URL may have changed.

- [ ] **Step 2: Create `content/styles/fontawesome-scoped.css`**

This defines the @font-face and scopes all FA selectors under `.rt-badge--ratio` to prevent global CSS pollution:

```css
@font-face {
  font-family: "Font Awesome 6 Free";
  font-style: normal;
  font-weight: 900;
  font-display: block;
  src: url("../fonts/fontawesome/fa-solid-900.woff2") format("woff2");
}

.rt-badge--ratio .fa-solid,
.rt-badge--ratio .fas {
  font-family: "Font Awesome 6 Free";
  font-weight: 900;
  -moz-osx-font-smoothing: grayscale;
  -webkit-font-smoothing: antialiased;
  display: inline-block;
  font-style: normal;
  font-variant: normal;
  line-height: 1;
  text-rendering: auto;
}

.rt-badge--ratio .fa-fire::before {
  content: "\f06d";
}
```

- [ ] **Step 3: Create `content/styles/ratio.css`**

This depends on `.rt-badge` base styles from `badges.css` (always loaded via manifest). It uses CSS custom properties `--rt-ratio-hue` and `--rt-ratio-sat` set inline by JS to derive all colors. Dark mode changes lightness via the `.rt-dark` selector — no JS DOM walk needed.

```css
/* --- Score ratio badge: temperature-colored --- */
.rt-badge--ratio {
  color: hsl(var(--rt-ratio-hue, 0), var(--rt-ratio-sat, 80%), 45%);
  background: hsla(var(--rt-ratio-hue, 0), var(--rt-ratio-sat, 80%), 45%, 0.1);
  border-color: hsla(var(--rt-ratio-hue, 0), var(--rt-ratio-sat, 80%), 45%, 0.25);
  cursor: default;
  gap: 3px;
  display: inline-flex;
  align-items: center;
}

.rt-badge--ratio .fa-solid {
  font-size: 10px;
}

/* --- Dark mode: bump lightness from 45% to 55% --- */
html.rt-dark .rt-badge--ratio,
.rt-dark .rt-badge--ratio {
  color: hsl(var(--rt-ratio-hue, 0), var(--rt-ratio-sat, 80%), 55%);
  background: hsla(var(--rt-ratio-hue, 0), var(--rt-ratio-sat, 80%), 55%, 0.1);
  border-color: hsla(var(--rt-ratio-hue, 0), var(--rt-ratio-sat, 80%), 55%, 0.25);
}

/* --- Neutral state for incalculable ratios (uses rt-badge base only, not rt-badge--ratio) --- */
.rt-badge--ratio-neutral {
  color: #737373;
  background: rgba(115, 115, 115, 0.1);
  border-color: rgba(115, 115, 115, 0.25);
  cursor: default;
}

html.rt-dark .rt-badge--ratio-neutral,
.rt-dark .rt-badge--ratio-neutral {
  color: #a3a3a3;
  background: rgba(163, 163, 163, 0.1);
  border-color: rgba(163, 163, 163, 0.25);
}

/* --- Disable hover effect on non-interactive ratio badges --- */
.rt-badge--ratio:hover,
.rt-badge--ratio-neutral:hover {
  opacity: 1;
}
```

- [ ] **Step 4: Add CSS files to `manifest.json`**

In the `content_scripts[0].css` array, add both new CSS files after `fonts.css`:

```json
"css": [
  "content/styles/badges.css",
  "content/styles/cards.css",
  "content/styles/fonts.css",
  "content/styles/fontawesome-scoped.css",
  "content/styles/ratio.css"
],
```

- [ ] **Step 5: Verify CSS loads without errors**

Reload extension. Navigate to `old.reddit.com`. Open the browser console:
- No CSS parse errors
- No 404 errors for the woff2 font file
- No visible changes yet (no JS creating badge elements)

- [ ] **Step 6: Commit**

```bash
git add content/fonts/fontawesome/fa-solid-900.woff2 content/styles/fontawesome-scoped.css content/styles/ratio.css manifest.json
git commit -m "feat: add FA solid subset and score ratio badge CSS"
```

---

### Task 3: Core ratio module + main.js integration

Create `ratio.js` with score parsing, comment count parsing, ratio calculation, HSL hue computation, and badge DOM injection. Wire it into `main.js` with enforced call order (after badges) and add to the manifest.

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

**Interfaces:**
- Consumes: `settings.scoreRatio` (boolean, from Task 1)
- Consumes: `.rt-badge` base styles from `badges.css`
- Consumes: `.rt-badge--ratio` styles from `ratio.css` (Task 2)
- Consumes: FA `fa-solid fa-fire` classes from `fontawesome-scoped.css` (Task 2)
- Produces: `window.RedditTweaks.ratioTweak.apply(settings)`
- Produces: `window.RedditTweaks.ratioTweak.processNewPosts(settings)`
- Produces: `window.RedditTweaks.ratioTweak.updateSettings(settings)` (no-op)

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

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

  var SCALE_MAX = 100;

  function parseScore(post) {
    var scoreEl = post.querySelector(".midcol .score.unvoted");
    if (!scoreEl) return null;

    var raw = scoreEl.getAttribute("title");
    if (raw && raw.indexOf("\u2022") === -1) {
      var parsed = parseInt(raw, 10);
      if (!isNaN(parsed)) return parsed;
    }

    var text = scoreEl.textContent.trim();
    if (!text || text.indexOf("\u2022") !== -1) return null;

    var num = parseInt(text, 10);
    if (!isNaN(num)) return num;

    var match = text.match(/^(-?[\d.]+)\s*([km])/i);
    if (match) {
      var val = parseFloat(match[1]);
      var suffix = match[2].toLowerCase();
      if (suffix === "k") return Math.round(val * 1000);
      if (suffix === "m") return Math.round(val * 1000000);
    }

    return null;
  }

  function parseCommentCount(post) {
    var commentsLink = post.querySelector(".flat-list .comments");
    if (!commentsLink) return null;

    var text = commentsLink.textContent.trim();
    if (text === "comment") return 0;

    var match = text.match(/^(\d+)/);
    return match ? parseInt(match[1], 10) : null;
  }

  function computeRatio(score, comments) {
    if (score === null || comments === null || comments === 0) return null;
    return score / comments;
  }

  function ratioToHue(ratio) {
    var clamped = Math.max(0, Math.min(ratio, SCALE_MAX));
    return Math.round(240 - (clamped / SCALE_MAX) * 240);
  }

  function processPost(post) {
    if (post.hasAttribute("data-rt-ratio-processed")) return;
    post.setAttribute("data-rt-ratio-processed", "true");

    var score = parseScore(post);
    var comments = parseCommentCount(post);
    var ratio = computeRatio(score, comments);

    var badge = document.createElement("span");

    if (ratio !== null) {
      badge.className = "rt-badge rt-badge--ratio";
      badge.style.setProperty("--rt-ratio-hue", String(ratioToHue(ratio)));
      badge.style.setProperty("--rt-ratio-sat", "80%");

      var text = document.createTextNode(ratio.toFixed(1) + " ");
      var icon = document.createElement("i");
      icon.className = "fa-solid fa-fire";
      badge.appendChild(text);
      badge.appendChild(icon);
    } else {
      badge.className = "rt-badge rt-badge--ratio-neutral";
      badge.textContent = "\u2014";
    }

    var container = post.querySelector(".reddit-tweaks-badges");
    if (container) {
      container.appendChild(badge);
    } else {
      var entry = post.querySelector(".entry");
      if (!entry) return;
      var tagline = entry.querySelector(".tagline");
      if (tagline && tagline.nextSibling) {
        entry.insertBefore(badge, tagline.nextSibling);
      } else if (tagline) {
        tagline.parentNode.appendChild(badge);
      } else {
        entry.insertBefore(badge, entry.firstChild);
      }
    }
  }

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

  function apply() {
    processPosts();
  }

  function updateSettings() {
    // No-op: dark mode lightness is handled via CSS selectors on .rt-dark
  }

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

- [ ] **Step 2: Add `ratio.js` to `manifest.json`**

In the `content_scripts[0].js` array, add `content/tweaks/ratio.js` after `cards.js` and 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/tweaks/ratio.js",
  "content/main.js"
],
```

- [ ] **Step 3: Wire ratio into `main.js` init**

In `content/main.js`, inside the `init()` function, add the ratio block **after** the `cardLayout` block (after line 76: `}`) and **before** the observer start (line 78: `if (settings.badgeLayout || settings.cardLayout)`):

```js
      if (settings.scoreRatio) {
        window.RedditTweaks.ratioTweak.apply(settings);
      }
```

- [ ] **Step 4: Wire ratio into post observer**

In `content/main.js`, inside the `startPostObserver` function, in the `if (hasNewPosts)` callback, add ratio processing **after** the `cardTweak.processNewPosts` call (after line 52: `}`):

```js
          if (settings.scoreRatio) {
            window.RedditTweaks.ratioTweak.processNewPosts(updated);
          }
```

- [ ] **Step 5: Wire ratio into dark mode observer**

In `content/main.js`, inside the `startDarkModeObserver` function, in the `if (updated.darkMode === "auto")` callback, add ratio update **after** the `cardTweak.updateSettings` call (after line 13: `}`):

```js
          if (updated.scoreRatio) {
            window.RedditTweaks.ratioTweak.updateSettings(updated);
          }
```

- [ ] **Step 6: Add `scoreRatio` to storage change reload triggers**

In `content/main.js`, in the `browser.storage.onChanged.addListener` callback, add `scoreRatio` to the reload condition (inside the `if` that checks for changes requiring reload, after the `cardLayout` check):

```js
          (changes.scoreRatio && changes.scoreRatio.newValue !== changes.scoreRatio.oldValue)
```

- [ ] **Step 7: Wire ratio into settings update listener**

In `content/main.js`, in the `browser.storage.onChanged.addListener` callback, in the `.then(function (updated))` block that runs when no reload is needed, add ratio update **after** the `cardTweak.updateSettings` call:

```js
          if (updated.scoreRatio) {
            window.RedditTweaks.ratioTweak.updateSettings(updated);
          }
```

- [ ] **Step 8: Verify end-to-end**

Reload extension. Navigate to `old.reddit.com`. Verify:
- Each post shows a colored ratio badge after the subreddit/comments badges
- Badge text is a number with one decimal followed by a fire icon (e.g., "28.7 🔥")
- Posts with high ratios (100+) show red badges
- Posts with low ratios show blue badges
- Posts with mid-range ratios show green/yellow badges
- Posts with hidden scores (• in the vote column) show "—" in gray
- Posts with 0 comments show "—" in gray
- Dark mode (toggle RES night mode or force dark in popup): badge colors shift slightly brighter, fire icon follows
- Infinite scroll (RES Never Ending Reddit): new posts get ratio badges
- Disabling "Score ratio badge" in popup and reloading: no ratio badges appear
- Re-enabling: badges return
- No console errors

- [ ] **Step 9: Commit**

```bash
git add content/tweaks/ratio.js content/main.js manifest.json
git commit -m "feat: add score ratio badge with temperature color scale"
```