feat: adaptive themeing

src/seqta/ui/colors/Manager.ts

@@ -1,8 +1,10 @@
 import browser from "webextension-polyfill";
+import Color from "color";
 import { GetThresholdOfColor } from "@/seqta/ui/colors/getThresholdColour";
 import { lightenAndPaleColor } from "./lightenAndPaleColor";
 import ColorLuminance from "./ColorLuminance";
 import { settingsState } from "@/seqta/utils/listeners/SettingsState";
+import { getAdaptiveColour } from "@/seqta/utils/adaptiveThemeColour";
 
 import darkLogo from "@/resources/icons/betterseqta-light-full.png";
 import lightLogo from "@/resources/icons/betterseqta-dark-full.png";
@@ -13,13 +15,7 @@ const setCSSVar = (varName: any, value: any) =>
 const applyProperties = (props: any) =>
   Object.entries(props).forEach(([key, value]) => setCSSVar(key, value));
 
-export function updateAllColors() {
-  // Determine the color to use
-  const selectedColor =
-    settingsState.selectedColor !== ""
-      ? settingsState.selectedColor
-      : "#007bff";
-
+function applyColorsWith(selectedColor: string) {
   if (settingsState.transparencyEffects) {
     document.documentElement.classList.add("transparencyEffects");
   }
@@ -28,7 +24,7 @@ export function updateAllColors() {
   const commonProps = {
     "--better-sub": "#161616",
     "--better-alert-highlight": "#c61851",
-    "--better-main": settingsState.selectedColor,
+    "--better-main": selectedColor,
   };
 
   // Mode-based properties, applied if storedSetting is provided
@@ -79,3 +75,29 @@ export function updateAllColors() {
     }
   }
 }
+
+function toSoftGradient(hex: string): string {
+  const base = Color(hex);
+  const analogous = base.rotate(30).lighten(0.25).saturate(0.15);
+  const mid = base.mix(analogous, 0.5).hex();
+  return `linear-gradient(135deg, ${hex} 0%, ${mid} 50%, ${analogous.hex()} 100%)`;
+}
+
+export async function updateAllColors() {
+  let effectiveColor =
+    settingsState.selectedColor !== ""
+      ? settingsState.selectedColor
+      : "#007bff";
+
+  if (settingsState.adaptiveThemeColour) {
+    const adaptiveColor = await getAdaptiveColour();
+    if (adaptiveColor) {
+      effectiveColor =
+        settingsState.adaptiveThemeGradient
+          ? toSoftGradient(adaptiveColor)
+          : adaptiveColor;
+    }
+  }
+
+  applyColorsWith(effectiveColor);
+}

src/seqta/utils/adaptiveThemeColour.ts

@@ -0,0 +1,114 @@
+import { getUserInfo } from "@/seqta/ui/AddBetterSEQTAElements";
+
+/**
+ * Parses the current page from window.location.hash.
+ * Returns { programme, metaclass } for /courses/SEMESTER/X:Y or /assessments/SEMESTER/X:Y, or null.
+ * e.g. #?page=/courses/2023S/4804:11066 or #?page=/assessments/2023S/4621:10772
+ */
+function parsePageContext(): { programme: number; metaclass: number } | null {
+  const hash = window.location.hash || "";
+  const match = hash.match(/[?&]page=\/(courses|assessments)\/[^/]+\/(\d+):(\d+)/);
+  if (!match) return null;
+  const programme = parseInt(match[2], 10);
+  const metaclass = parseInt(match[3], 10);
+  if (isNaN(programme) || isNaN(metaclass)) return null;
+  return { programme, metaclass };
+}
+
+/**
+ * Fetches subjects and finds the subject matching programme:metaclass.
+ */
+async function getSubjectCode(
+  programme: number,
+  metaclass: number
+): Promise<string | null> {
+  try {
+    const res = await fetch(`${location.origin}/seqta/student/load/subjects?`, {
+      method: "POST",
+      credentials: "include",
+      headers: { "Content-Type": "application/json; charset=utf-8" },
+      body: JSON.stringify({}),
+    });
+    const data = await res.json();
+    const payload = data?.payload;
+    if (!Array.isArray(payload)) return null;
+
+    for (const semester of payload) {
+      const subjects = semester?.subjects;
+      if (!Array.isArray(subjects)) continue;
+      const subject = subjects.find(
+        (s: any) =>
+          s &&
+          Number(s.programme) === programme &&
+          Number(s.metaclass) === metaclass
+      );
+      if (subject?.code) return subject.code;
+    }
+    return null;
+  } catch (error) {
+    console.warn("[BetterSEQTA+] Adaptive theme: failed to load subjects:", error);
+    return null;
+  }
+}
+
+/**
+ * Fetches user prefs and returns the colour for the given subject code.
+ */
+async function getSubjectColour(
+  subjectCode: string,
+  userId: number
+): Promise<string | null> {
+  try {
+    const res = await fetch(`${location.origin}/seqta/student/load/prefs?`, {
+      method: "POST",
+      credentials: "include",
+      headers: { "Content-Type": "application/json; charset=utf-8" },
+      body: JSON.stringify({
+        request: "userPrefs",
+        asArray: true,
+        user: userId,
+      }),
+    });
+    const data = await res.json();
+    const payload = data?.payload;
+    if (!Array.isArray(payload)) return null;
+
+    const pref = payload.find(
+      (p: { name: string; value: string }) =>
+        p.name === `timetable.subject.colour.${subjectCode}`
+    );
+    return pref?.value ?? null;
+  } catch (error) {
+    console.warn("[BetterSEQTA+] Adaptive theme: failed to load prefs:", error);
+    return null;
+  }
+}
+
+/**
+ * Returns the adaptive theme colour for the current page context, or null.
+ * When viewing a course or assessments page, returns the subject's assigned colour.
+ */
+export async function getAdaptiveColour(): Promise<string | null> {
+  const context = parsePageContext();
+  if (!context) return null;
+
+  const subjectCode = await getSubjectCode(context.programme, context.metaclass);
+  if (!subjectCode) return null;
+
+  let userId: number;
+  try {
+    const userInfo = await getUserInfo();
+    userId = userInfo?.id;
+    if (typeof userId !== "number") return null;
+  } catch {
+    return null;
+  }
+
+  const colour = await getSubjectColour(subjectCode, userId);
+  if (!colour || typeof colour !== "string") return null;
+
+  // Basic hex validation
+  if (/^#([0-9A-Fa-f]{3}){1,2}$/.test(colour)) return colour;
+  if (/^[0-9A-Fa-f]{6}$/.test(colour)) return `#${colour}`;
+  return null;
+}

src/seqta/utils/listeners/StorageChanges.ts

@@ -14,7 +14,9 @@ export class StorageChangeHandler {
   }
 
   private registerHandlers() {
-    settingsState.register("selectedColor", updateAllColors.bind(this));
+    settingsState.register("selectedColor", () => void updateAllColors());
+    settingsState.register("adaptiveThemeColour", () => void updateAllColors());
+    settingsState.register("adaptiveThemeGradient", () => void updateAllColors());
     settingsState.register("DarkMode", this.handleDarkModeChange.bind(this));
     settingsState.register("onoff", this.handleOnOffChange.bind(this));
     settingsState.register("shortcuts", this.handleShortcutsChange.bind(this));
@@ -45,7 +47,7 @@ export class StorageChangeHandler {
   }
 
   private handleDarkModeChange() {
-    updateAllColors();
+    void updateAllColors();
   }
 
   private handleOnOffChange(newValue: boolean) {