feat: Background color fetching

scrape/parse/v3.js

@@ -16,10 +16,94 @@ import fs from "fs";
 import parseAbsence from "../utils/parseAbsence.js"
 import parseTeachers from "../utils/parseTeachers.js"
 import ExcelJS from "exceljs"
+import JSZip from "jszip";
+import { parseStringPromise } from "xml2js";
+
+/**
+ * Read theme colors from the workbook
+ */
+async function getThemeColors(filePath) {
+  const data = fs.readFileSync(filePath);
+  const zip = await JSZip.loadAsync(data);
+
+  // list all files for debug
+
+  const themeFile = zip.file("xl/theme/theme1.xml");
+  if (!themeFile) {
+    return null;
+  }
+
+  const themeXml = await themeFile.async("text");
+  const theme = await parseStringPromise(themeXml);
+  const scheme = theme["a:theme"]?.["a:themeElements"]?.[0]?.["a:clrScheme"]?.[0];
+
+  if (!scheme) return null;
+
+  function getColor(node) {
+    if (node["a:srgbClr"]) return node["a:srgbClr"][0].$.val;
+    if (node["a:sysClr"]) return node["a:sysClr"][0].$.lastClr;
+    return null;
+  }
+
+  const colors = {
+    0: getColor(scheme["a:dk1"]?.[0]),
+    1: getColor(scheme["a:lt1"]?.[0]),
+    2: getColor(scheme["a:dk2"]?.[0]),
+    3: getColor(scheme["a:lt2"]?.[0]),
+    4: getColor(scheme["a:accent1"]?.[0]),
+    5: getColor(scheme["a:accent2"]?.[0]),
+    6: getColor(scheme["a:accent3"]?.[0]),
+    7: getColor(scheme["a:accent4"]?.[0]),
+    8: getColor(scheme["a:accent5"]?.[0]),
+    9: getColor(scheme["a:accent6"]?.[0]),
+  };
+
+  return colors;
+}
+
+/**
+ * Apply Excel tint to a base hex color
+ */
+function applyTintToHex(hex, tint = 0) {
+  const r = parseInt(hex.slice(0, 2), 16);
+  const g = parseInt(hex.slice(2, 4), 16);
+  const b = parseInt(hex.slice(4, 6), 16);
+
+  const tintChannel = (c) =>
+    tint > 0 ? Math.round(c + (255 - c) * tint) : Math.round(c * (1 + tint));
+
+  const nr = tintChannel(r);
+  const ng = tintChannel(g);
+  const nb = tintChannel(b);
+
+  return [nr, ng, nb]
+    .map((v) => v.toString(16).padStart(2, "0"))
+    .join("")
+    .toUpperCase();
+}
+
+/**
+ * Resolve final hex for a cell fill
+ */
+function resolveCellColor(cell, themeColors) {
+  if (!cell.fill?.fgColor) return null;
+
+  const fg = cell.fill.fgColor;
+
+  if (fg.argb) return `#${fg.argb}`;
+  if (fg.theme !== undefined && themeColors) {
+    const base = themeColors[fg.theme];
+    if (!base) return null;
+    return `#${applyTintToHex(base, fg.tint ?? 0)}`;
+  }
+
+  return null;
+}
 
 export default async function parseV3(downloadedFilePath) {
   const workbook = new ExcelJS.Workbook();
   await workbook.xlsx.readFile(downloadedFilePath);
+  const themeColors = await getThemeColors(downloadedFilePath);
 
   const teacherMap = await parseTeachers();
 
@@ -29,7 +113,7 @@ export default async function parseV3(downloadedFilePath) {
   const schedule = {};
 
   for (const { dateKey, sheet } of resolvedDays) {
-    const { changes, absence, inWork, takesPlace, reservedRooms } = extractDaySchedule(sheet, teacherMap);
+    const { changes, absence, inWork, takesPlace, reservedRooms } = extractDaySchedule(sheet, teacherMap, themeColors);
 
     schedule[dateKey] = {
       info: { inWork },
@@ -104,9 +188,9 @@ function groupSheetsByDate(items) {
 // ────────────────────────────────────────────────────────────
 //
 
-function extractDaySchedule(sheet, teacherMap) {
+function extractDaySchedule(sheet, teacherMap, themeColors) {
   return {
-    changes: extractClassChanges(sheet),
+    changes: extractClassChanges(sheet, themeColors),
     absence: extractAbsence(sheet, teacherMap),
     inWork: isPripravaSheet(sheet.name.toLowerCase()),
     takesPlace: extractTakesPlace(sheet),
@@ -128,7 +212,7 @@ function isPripravaSheet(name) {
 // ────────────────────────────────────────────────────────────
 //
 
-function extractClassChanges(sheet) {
+function extractClassChanges(sheet, themeColors) {
   const classRegex = /[AEC][0-4][a-c]?\s*\/.*/s;
   const prefixRegex = /[AEC][0-4][a-c]?/;
 
@@ -150,20 +234,20 @@ function extractClassChanges(sheet) {
 
   classCells.forEach((address, index) => {
     const row = sheet.getRow(sheet.getCell(address).row);
-    changes[classes[index]] = buildLessonArray(row, address);
+    changes[classes[index]] = buildLessonArray(row, address, themeColors);
   });
 
   return changes;
 }
 
-function buildLessonArray(row, ignoreAddress) {
+function buildLessonArray(row, ignoreAddress, themeColors) {
   const lessons = [];
 
   row.eachCell((cell) => {
     if (cell.address === ignoreAddress) return;
 
     const colIndex = letterToNumber(cell.address.replace(/[0-9]/g, ""));
-    lessons[colIndex] = parseLessonCell(cell);
+    lessons[colIndex] = parseLessonCell(cell, themeColors);
   });
 
   const normalized = Array.from(lessons, (x) => (x === undefined ? null : x));
@@ -172,15 +256,15 @@ function buildLessonArray(row, ignoreAddress) {
   return normalized.slice(1, 11);
 }
 
-function parseLessonCell(cell) {
+function parseLessonCell(cell, themeColors) {
   try {
     const text = (cell.text || "").trim();
     const cleanupRegex = /^úklid\s+(?:\d+\s+)?[A-Za-z]{2}$/;
 
     if (!text || cleanupRegex.test(text) || !cell.fill?.fgColor) return null;
 
-    const backgroundColor = cell.fill.fgColor.argb === undefined ? undefined : `#${cell.fill.fgColor.argb}`;
-    const foregroundColor = backgroundColor === undefined ? undefined : (
+    const backgroundColor = resolveCellColor(cell, themeColors);
+    const foregroundColor = !backgroundColor ? undefined : (
       cell.font?.color?.argb === undefined ? undefined : `#${cell.font.color.argb}`
     );
 
@@ -318,4 +402,4 @@ function formatNowTime() {
   );
 }
 
-//parseV3("db/current.xlsx")
+parseV3("db/current.xlsx")