Upsert reading log entries to have one per day per book

src/utils/ReadingLog.ts

@@ -8,6 +8,14 @@ export interface ReadingLogEntry {
 	createdAt: Date;
 }
 
+function isSameDay(a: Date, b: Date): boolean {
+	return (
+		a.getFullYear() === b.getFullYear() &&
+		a.getMonth() === b.getMonth() &&
+		a.getDate() === b.getDate()
+	);
+}
+
 export class ReadingLog {
 	private entries: ReadingLogEntry[] = [];
 
@@ -77,8 +85,13 @@ export class ReadingLog {
 			createdAt: new Date(),
 		};
 
+		if (lastEntry && isSameDay(lastEntry.createdAt, newEntry.createdAt)) {
+			newEntry.pagesRead += lastEntry.pagesRead;
+			await this.updateEntry(this.entries.indexOf(lastEntry), lastEntry);
+		} else {
 			await this.addRawEntry(newEntry);
 		}
+	}
 
 	public async addRawEntry(entry: ReadingLogEntry) {
 		this.entries.push(entry);