Fix CSV parsing issue with trailing whitespace in headers

Co-authored-by: rajbos <6085745+rajbos@users.noreply.github.com>

Author: Copilot

src/lib/utils.ts

@@ -32,16 +32,20 @@ export function parseCSV(csv: string): CopilotUsageData[] {
   const expectedHeaders = ['Timestamp', 'User', 'Model', 'Requests Used', 'Exceeds Monthly Quota', 'Total Monthly Quota'];
 
   // Parse header row to check for expected columns
-  const headerMatches = headerLine.match(/("([^"]*)"|([^,]*))(,|$)/g);
+  // First, trim any trailing whitespace from the header line
+  const trimmedHeaderLine = headerLine.trim();
+  const headerMatches = trimmedHeaderLine.match(/("([^"]*)"|([^,]*))(,|$)/g);
   if (!headerMatches || headerMatches.length < 6) {
     throw new Error('CSV header must contain at least 6 columns');
   }
 
-  const headers = headerMatches.map(m => 
-    m.endsWith(',') 
-      ? m.slice(0, -1).replace(/^"(.*)"$/, '$1') 
-      : m.replace(/^"(.*)"$/, '$1')
-  ).filter(h => h.trim() !== '').map(h => h.trim()); // Filter empty strings and trim whitespace
+  const headers = headerMatches.map(m => {
+    // Remove trailing comma if present
+    let processed = m.endsWith(',') ? m.slice(0, -1) : m;
+    // Remove surrounding quotes if present
+    processed = processed.replace(/^"(.*)"$/, '$1');
+    return processed;
+  }).filter(h => h.trim() !== '').map(h => h.trim()); // Filter empty strings and trim whitespace
 
   // Check if all expected headers are present (case-insensitive exact match)
   const missingHeaders = expectedHeaders.filter(expected => 
@@ -71,18 +75,21 @@ export function parseCSV(csv: string): CopilotUsageData[] {
 
   // Skip the header row and process data rows
   return lines.slice(1).map((line, index) => {
-    // Handle quoted CSV properly
-    const matches = line.match(/("([^"]*)"|([^,]*))(,|$)/g);
+    // Handle quoted CSV properly - trim any trailing whitespace first
+    const trimmedLine = line.trim();
+    const matches = trimmedLine.match(/("([^"]*)"|([^,]*))(,|$)/g);
 
     if (!matches || matches.length < 6) {
       throw new Error(`Invalid CSV row format at line ${index + 2}: expected 6 columns, got ${matches ? matches.length : 0}`);
     }
 
-    const values = matches.map(m => 
-      m.endsWith(',') 
-        ? m.slice(0, -1).replace(/^"(.*)"$/, '$1') 
-        : m.replace(/^"(.*)"$/, '$1')
-    );
+    const values = matches.map(m => {
+      // Remove trailing comma if present
+      let processed = m.endsWith(',') ? m.slice(0, -1) : m;
+      // Remove surrounding quotes if present
+      processed = processed.replace(/^"(.*)"$/, '$1');
+      return processed;
+    }).filter(v => v.trim() !== ''); // Filter out empty values
 
     // Validate timestamp
     const timestamp = new Date(values[0]);

src/test/csv-user-issue.test.ts

@@ -0,0 +1,56 @@
+import { describe, it, expect } from 'vitest';
+import { parseCSV } from '../lib/utils';
+
+describe('CSV Parsing Issue Reproduction', () => {
+  it('should handle the exact CSV format provided by user', () => {
+    const csvContent = `"Timestamp","User","Model","Requests Used","Exceeds Monthly Quota","Total Monthly Quota"
+"2025-06-11T05:13:27.8766440Z","xyz","gpt-4.1-2025-04-14","1","False","Unlimited"
+"2025-06-11T05:09:40.8432110Z","xyz","gpt-4.1-2025-04-14","1","False","Unlimited"`;
+
+    console.log('Testing user CSV content:');
+    console.log(csvContent);
+    console.log('');
+
+    // This should parse without issues
+    expect(() => parseCSV(csvContent)).not.toThrow();
+    
+    const result = parseCSV(csvContent);
+    expect(result).toHaveLength(2);
+    expect(result[0].user).toBe('xyz');
+    expect(result[0].model).toBe('gpt-4.1-2025-04-14');
+    expect(result[0].requestsUsed).toBe(1);
+    expect(result[0].exceedsQuota).toBe(false);
+    expect(result[0].totalMonthlyQuota).toBe('Unlimited');
+  });
+
+  it('should handle header with potential whitespace issues', () => {
+    // Test with potential whitespace or encoding issues
+    const csvWithExtraSpacing = `"Timestamp","User","Model","Requests Used","Exceeds Monthly Quota","Total Monthly Quota" 
+"2025-06-11T05:13:27.8766440Z","xyz","gpt-4.1-2025-04-14","1","False","Unlimited"`;
+
+    expect(() => parseCSV(csvWithExtraSpacing)).not.toThrow();
+    
+    const result = parseCSV(csvWithExtraSpacing);
+    expect(result).toHaveLength(1);
+    expect(result[0].totalMonthlyQuota).toBe('Unlimited');
+  });
+
+  it('should handle header without quotes', () => {
+    const csvWithoutQuotes = `Timestamp,User,Model,Requests Used,Exceeds Monthly Quota,Total Monthly Quota
+2025-06-11T05:13:27.8766440Z,xyz,gpt-4.1-2025-04-14,1,False,Unlimited`;
+
+    expect(() => parseCSV(csvWithoutQuotes)).not.toThrow();
+    const result = parseCSV(csvWithoutQuotes);
+    expect(result).toHaveLength(1);
+  });
+
+  it('should handle data rows with trailing spaces', () => {
+    const csvWithTrailingSpaceInData = `"Timestamp","User","Model","Requests Used","Exceeds Monthly Quota","Total Monthly Quota"
+"2025-06-11T05:13:27.8766440Z","xyz","gpt-4.1-2025-04-14","1","False","Unlimited" `;
+
+    expect(() => parseCSV(csvWithTrailingSpaceInData)).not.toThrow();
+    const result = parseCSV(csvWithTrailingSpaceInData);
+    expect(result).toHaveLength(1);
+    expect(result[0].totalMonthlyQuota).toBe('Unlimited');
+  });
+});