feat(comments): support custom giscus themes (#1526)

Co-authored-by: Aaron Pham <Aaronpham0103@gmail.com>
Co-authored-by: Aaron Pham <contact@aarnphm.xyz>

docs/features/comments.md

@@ -63,6 +63,18 @@ type Options = {
     category: string
     categoryId: string
 
+    // Url to folder with custom themes
+    // defaults to 'https://${cfg.baseUrl}/static/giscus'
+    themeUrl?: string
+
+    // filename for light theme .css file
+    // defaults to 'light'
+    lightTheme?: string
+
+    // filename for dark theme .css file
+    // defaults to 'dark'
+    darkTheme?: string
+
     // how to map pages -> discussions
     // defaults to 'url'
     mapping?: "url" | "title" | "og:title" | "specific" | "number" | "pathname"
@@ -81,3 +93,24 @@ type Options = {
   }
 }
 ```
+
+#### Custom CSS theme
+
+Quartz supports custom theme for Giscus. To use a custom CSS theme, place the `.css` file inside the `quartz/static` folder and set the configuration values.
+
+For example, if you have a light theme `light-theme.css`, a dark theme `dark-theme.css`, and your Quartz site is hosted at `https://example.com/`:
+
+```ts
+afterBody: [
+  Component.Comments({
+    provider: 'giscus',
+    options: {
+      // Other options
+
+      themeUrl: "https://example.com/static/giscus", // corresponds to quartz/static/giscus/
+      lightTheme: "light-theme", // corresponds to light-theme.css in quartz/static/giscus/
+      darkTheme: "dark-theme", // corresponds to dark-theme.css quartz/static/giscus/
+    }
+  }),
+],
+```

quartz/components/Comments.tsx

@@ -10,6 +10,9 @@ type Options = {
     repoId: string
     category: string
     categoryId: string
+    themeUrl?: string
+    lightTheme?: string
+    darkTheme?: string
     mapping?: "url" | "title" | "og:title" | "specific" | "number" | "pathname"
     strict?: boolean
     reactionsEnabled?: boolean
@@ -34,6 +37,11 @@ export default ((opts: Options) => {
         data-strict={boolToStringBool(opts.options.strict ?? true)}
         data-reactions-enabled={boolToStringBool(opts.options.reactionsEnabled ?? true)}
         data-input-position={opts.options.inputPosition ?? "bottom"}
+        data-light-theme={opts.options.lightTheme ?? "light"}
+        data-dark-theme={opts.options.darkTheme ?? "dark"}
+        data-theme-url={
+          opts.options.themeUrl ?? `https://${cfg.baseUrl ?? "example.com"}/static/giscus`
+        }
       ></div>
     )
   }

quartz/components/scripts/comments.inline.ts

@@ -13,7 +13,7 @@ const changeTheme = (e: CustomEventMap["themechange"]) => {
     {
       giscus: {
         setConfig: {
-          theme: theme,
+          theme: getThemeUrl(getThemeName(theme)),
         },
       },
     },
@@ -21,12 +21,36 @@ const changeTheme = (e: CustomEventMap["themechange"]) => {
   )
 }
 
+const getThemeName = (theme: string) => {
+  if (theme !== "dark" && theme !== "light") {
+    return theme
+  }
+  const giscusContainer = document.querySelector(".giscus") as GiscusElement
+  if (!giscusContainer) {
+    return theme
+  }
+  const darkGiscus = giscusContainer.dataset.darkTheme ?? "dark"
+  const lightGiscus = giscusContainer.dataset.lightTheme ?? "light"
+  return theme === "dark" ? darkGiscus : lightGiscus
+}
+
+const getThemeUrl = (theme: string) => {
+  const giscusContainer = document.querySelector(".giscus") as GiscusElement
+  if (!giscusContainer) {
+    return `https://giscus.app/themes/${theme}.css`
+  }
+  return `${giscusContainer.dataset.themeUrl ?? "https://giscus.app/themes"}/${theme}.css`
+}
+
 type GiscusElement = Omit<HTMLElement, "dataset"> & {
   dataset: DOMStringMap & {
     repo: `${string}/${string}`
     repoId: string
     category: string
     categoryId: string
+    themeUrl: string
+    lightTheme: string
+    darkTheme: string
     mapping: "url" | "title" | "og:title" | "specific" | "number" | "pathname"
     strict: string
     reactionsEnabled: string
@@ -57,7 +81,7 @@ document.addEventListener("nav", () => {
 
   const theme = document.documentElement.getAttribute("saved-theme")
   if (theme) {
-    giscusScript.setAttribute("data-theme", theme)
+    giscusScript.setAttribute("data-theme", getThemeUrl(getThemeName(theme)))
   }
 
   giscusContainer.appendChild(giscusScript)

quartz/static/giscus/dark.css

@@ -0,0 +1,99 @@
+/*! MIT License
+ * Copyright (c) 2018 GitHub Inc.
+ * https://github.com/primer/primitives/blob/main/LICENSE
+ */
+
+main {
+  --color-prettylights-syntax-comment: #8b949e;
+  --color-prettylights-syntax-constant: #79c0ff;
+  --color-prettylights-syntax-entity: #d2a8ff;
+  --color-prettylights-syntax-storage-modifier-import: #c9d1d9;
+  --color-prettylights-syntax-entity-tag: #7ee787;
+  --color-prettylights-syntax-keyword: #ff7b72;
+  --color-prettylights-syntax-string: #a5d6ff;
+  --color-prettylights-syntax-variable: #ffa657;
+  --color-prettylights-syntax-brackethighlighter-unmatched: #f85149;
+  --color-prettylights-syntax-invalid-illegal-text: #f0f6fc;
+  --color-prettylights-syntax-invalid-illegal-bg: #8e1519;
+  --color-prettylights-syntax-carriage-return-text: #f0f6fc;
+  --color-prettylights-syntax-carriage-return-bg: #b62324;
+  --color-prettylights-syntax-string-regexp: #7ee787;
+  --color-prettylights-syntax-markup-list: #f2cc60;
+  --color-prettylights-syntax-markup-heading: #1f6feb;
+  --color-prettylights-syntax-markup-italic: #c9d1d9;
+  --color-prettylights-syntax-markup-bold: #c9d1d9;
+  --color-prettylights-syntax-markup-deleted-text: #ffdcd7;
+  --color-prettylights-syntax-markup-deleted-bg: #67060c;
+  --color-prettylights-syntax-markup-inserted-text: #aff5b4;
+  --color-prettylights-syntax-markup-inserted-bg: #033a16;
+  --color-prettylights-syntax-markup-changed-text: #ffdfb6;
+  --color-prettylights-syntax-markup-changed-bg: #5a1e02;
+  --color-prettylights-syntax-markup-ignored-text: #c9d1d9;
+  --color-prettylights-syntax-markup-ignored-bg: #1158c7;
+  --color-prettylights-syntax-meta-diff-range: #d2a8ff;
+  --color-prettylights-syntax-brackethighlighter-angle: #8b949e;
+  --color-prettylights-syntax-sublimelinter-gutter-mark: #484f58;
+  --color-prettylights-syntax-constant-other-reference-link: #a5d6ff;
+  --color-btn-text: #d4d4d4; /* --darkgray */
+  --color-btn-bg: #161618; /* --light */
+  --color-btn-border: rgb(240, 246, 252 / 10%); /* --dark */
+  --color-btn-shadow: 0 0 transparent;
+  --color-btn-inset-shadow: 0 0 transparent;
+  --color-btn-hover-bg: #30363d;
+  --color-btn-hover-border: #8b949e;
+  --color-btn-active-bg: hsl(212deg 12% 18% / 100%);
+  --color-btn-active-border: #6e7681;
+  --color-btn-selected-bg: #161b22;
+  --color-btn-primary-text: #fff;
+  --color-btn-primary-bg: #84a59d; /* --tertiary */
+  --color-btn-primary-border: rgb(240, 246, 252 / 10%); /* --dark */
+  --color-btn-primary-shadow: 0 0 transparent;
+  --color-btn-primary-inset-shadow: 0 0 transparent;
+  --color-btn-primary-hover-bg: #7b97aa; /* --secondary */
+  --color-btn-primary-hover-border: rgb(240, 246, 252 / 10%); /* --dark */
+  --color-btn-primary-selected-bg: #7b97aa; /* --secondary */
+  --color-btn-primary-selected-shadow: 0 0 transparent;
+  --color-btn-primary-disabled-text: rgba(33, 32, 32, 0.5);
+  --color-btn-primary-disabled-bg: rgb(35 134 54 / 60%);
+  --color-btn-primary-disabled-border: rgb(240 246 252 / 10%);
+  --color-action-list-item-default-hover-bg: rgb(177 186 196 / 12%);
+  --color-segmented-control-bg: rgb(110 118 129 / 10%);
+  --color-segmented-control-button-bg: #0d1117;
+  --color-segmented-control-button-selected-border: #6e7681;
+  --color-fg-default: #ebebec; /* --dark */
+  --color-fg-muted: #d4d4d4; /* --darkgray */
+  --color-fg-subtle: #d4d4d4; /* --darkgray */
+  --color-canvas-default: #0d1117;
+  --color-canvas-overlay: #161b22;
+  --color-canvas-inset: #010409;
+  --color-canvas-subtle: #161b22;
+  --color-border-default: #30363d;
+  --color-border-muted: #21262d;
+  --color-neutral-muted: rgb(110 118 129 / 40%);
+  --color-accent-fg: #2f81f7;
+  --color-accent-emphasis: #1f6feb;
+  --color-accent-muted: rgb(56 139 253 / 40%);
+  --color-accent-subtle: rgb(56 139 253 / 10%);
+  --color-success-fg: #3fb950;
+  --color-attention-fg: #d29922;
+  --color-attention-muted: rgb(187 128 9 / 40%);
+  --color-attention-subtle: rgb(187 128 9 / 15%);
+  --color-danger-fg: #f85149;
+  --color-danger-muted: rgb(248 81 73 / 40%);
+  --color-danger-subtle: rgb(248 81 73 / 10%);
+  --color-primer-shadow-inset: 0 0 transparent;
+  --color-scale-gray-7: #21262d;
+  --color-scale-blue-8: #0c2d6b;
+
+  /*! Extensions from @primer/css/alerts/flash.scss */
+  --color-social-reaction-bg-hover: var(--color-scale-gray-7);
+  --color-social-reaction-bg-reacted-hover: var(--color-scale-blue-8);
+}
+
+main .pagination-loader-container {
+  background-image: url("https://github.com/images/modules/pulls/progressive-disclosure-line-dark.svg");
+}
+
+main .gsc-loading-image {
+  background-image: url("https://github.githubassets.com/images/mona-loading-dark.gif");
+}

quartz/static/giscus/light.css

@@ -0,0 +1,99 @@
+/*! MIT License
+ * Copyright (c) 2018 GitHub Inc.
+ * https://github.com/primer/primitives/blob/main/LICENSE
+ */
+
+main {
+  --color-prettylights-syntax-comment: #6e7781;
+  --color-prettylights-syntax-constant: #0550ae;
+  --color-prettylights-syntax-entity: #8250df;
+  --color-prettylights-syntax-storage-modifier-import: #24292f;
+  --color-prettylights-syntax-entity-tag: #116329;
+  --color-prettylights-syntax-keyword: #cf222e;
+  --color-prettylights-syntax-string: #0a3069;
+  --color-prettylights-syntax-variable: #953800;
+  --color-prettylights-syntax-brackethighlighter-unmatched: #82071e;
+  --color-prettylights-syntax-invalid-illegal-text: #f6f8fa;
+  --color-prettylights-syntax-invalid-illegal-bg: #82071e;
+  --color-prettylights-syntax-carriage-return-text: #f6f8fa;
+  --color-prettylights-syntax-carriage-return-bg: #cf222e;
+  --color-prettylights-syntax-string-regexp: #116329;
+  --color-prettylights-syntax-markup-list: #3b2300;
+  --color-prettylights-syntax-markup-heading: #0550ae;
+  --color-prettylights-syntax-markup-italic: #24292f;
+  --color-prettylights-syntax-markup-bold: #24292f;
+  --color-prettylights-syntax-markup-deleted-text: #82071e;
+  --color-prettylights-syntax-markup-deleted-bg: #ffebe9;
+  --color-prettylights-syntax-markup-inserted-text: #116329;
+  --color-prettylights-syntax-markup-inserted-bg: #dafbe1;
+  --color-prettylights-syntax-markup-changed-text: #953800;
+  --color-prettylights-syntax-markup-changed-bg: #ffd8b5;
+  --color-prettylights-syntax-markup-ignored-text: #eaeef2;
+  --color-prettylights-syntax-markup-ignored-bg: #0550ae;
+  --color-prettylights-syntax-meta-diff-range: #8250df;
+  --color-prettylights-syntax-brackethighlighter-angle: #57606a;
+  --color-prettylights-syntax-sublimelinter-gutter-mark: #8c959f;
+  --color-prettylights-syntax-constant-other-reference-link: #0a3069;
+  --color-btn-text: #4e4e4e; /* --darkgray */
+  --color-btn-bg: #faf8f8; /* --light */
+  --color-btn-border: rgb(43, 43, 43 / 15%); /* --dark */
+  --color-btn-shadow: 0 1px 0 rgb(31 35 40 / 4%);
+  --color-btn-inset-shadow: inset 0 1px 0 rgb(255 255 255 / 25%);
+  --color-btn-hover-bg: #f3f4f6;
+  --color-btn-hover-border: rgb(43, 43, 43 / 15%); /* --dark */
+  --color-btn-active-bg: hsl(220deg 14% 93% / 100%);
+  --color-btn-active-border: rgb(31 35 40 / 15%);
+  --color-btn-selected-bg: hsl(220deg 14% 94% / 100%);
+  --color-btn-primary-text: #fff;
+  --color-btn-primary-bg: #84a59d; /* --tertiary */
+  --color-btn-primary-border: rgb(43, 43, 43 / 15%); /* --dark */
+  --color-btn-primary-shadow: 0 1px 0 rgb(31 35 40 / 10%);
+  --color-btn-primary-inset-shadow: inset 0 1px 0 rgb(255 255 255 / 3%);
+  --color-btn-primary-hover-bg: #284b63; /* --secondary */
+  --color-btn-primary-hover-border: rgb(43, 43, 43 / 15%); /* --dark */
+  --color-btn-primary-selected-bg: #284b63; /* --secondary */
+  --color-btn-primary-selected-shadow: inset 0 1px 0 rgb(0 45 17 / 20%);
+  --color-btn-primary-disabled-text: rgb(255 255 255 / 80%);
+  --color-btn-primary-disabled-bg: #94d3a2;
+  --color-btn-primary-disabled-border: rgb(31 35 40 / 15%);
+  --color-action-list-item-default-hover-bg: rgb(208 215 222 / 32%);
+  --color-segmented-control-bg: #eaeef2;
+  --color-segmented-control-button-bg: #fff;
+  --color-segmented-control-button-selected-border: #8c959f;
+  --color-fg-default: #2b2b2b; /* --dark */
+  --color-fg-muted: #4e4e4e; /* --darkgray */
+  --color-fg-subtle: #4e4e4e; /* --darkgray */
+  --color-canvas-default: #fff;
+  --color-canvas-overlay: #fff;
+  --color-canvas-inset: #f6f8fa;
+  --color-canvas-subtle: #f6f8fa;
+  --color-border-default: #d0d7de;
+  --color-border-muted: hsl(210deg 18% 87% / 100%);
+  --color-neutral-muted: rgb(175 184 193 / 20%);
+  --color-accent-fg: #0969da;
+  --color-accent-emphasis: #0969da;
+  --color-accent-muted: rgb(84 174 255 / 40%);
+  --color-accent-subtle: #ddf4ff;
+  --color-success-fg: #1a7f37;
+  --color-attention-fg: #9a6700;
+  --color-attention-muted: rgb(212 167 44 / 40%);
+  --color-attention-subtle: #fff8c5;
+  --color-danger-fg: #d1242f;
+  --color-danger-muted: rgb(255 129 130 / 40%);
+  --color-danger-subtle: #ffebe9;
+  --color-primer-shadow-inset: inset 0 1px 0 rgb(208 215 222 / 20%);
+  --color-scale-gray-1: #eaeef2;
+  --color-scale-blue-1: #b6e3ff;
+
+  /*! Extensions from @primer/css/alerts/flash.scss */
+  --color-social-reaction-bg-hover: var(--color-scale-gray-1);
+  --color-social-reaction-bg-reacted-hover: var(--color-scale-blue-1);
+}
+
+main .pagination-loader-container {
+  background-image: url("https://github.com/images/modules/pulls/progressive-disclosure-line.svg");
+}
+
+main .gsc-loading-image {
+  background-image: url("https://github.githubassets.com/images/mona-loading-default.gif");
+}