feat: add VCF to CSV converter

[kunal763]

This PR adds support for converting VCF (vCard) contact files to CSV format, addressing issue #396. The implementation provides a pure TypeScript solution without external dependencies.

• New Features
  • Register vcf -> csv converter in the main registry and update README.
  • Parse FN, N, TEL/EMAIL (including TYPE params), and ORG; generate CSV with proper quote escaping.
  • Add tests covering single/multiple cards, TYPE parameters, quote escaping, and empty data.

VCF Parsing

• Multi-contact support: Handles multiple vCards in single file
• Field extraction: Parses FN, N, TEL, EMAIL, ORG fields
• TYPE parameter handling: Ignores TYPE attributes (WORK, HOME, PREF, etc.)
• Robust parsing: Regex-based splitting with error resilience

[cubic-dev-ai]

3 issues found across 4 files

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="src/converters/vcf.ts">

<violation number="1" location="src/converters/vcf.ts:28">
P1: VCF parsing ignores vCard parameters and folded lines, dropping FN/N values and truncating long fields</violation>

<violation number="2" location="src/converters/vcf.ts:51">
P1: CSV headers are derived only from the first contact, so fields present only in later contacts are omitted and their values are dropped from the CSV output.</violation>

<violation number="3" location="src/converters/vcf.ts:52">
P1: CSV output does not neutralize leading formula characters, allowing spreadsheet formula injection if VCF data starts with =, +, - or @.</violation>
</file>

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[cubic-dev-ai]

P1: CSV output does not neutralize leading formula characters, allowing spreadsheet formula injection if VCF data starts with =, +, - or @.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/converters/vcf.ts, line 52:

<comment>CSV output does not neutralize leading formula characters, allowing spreadsheet formula injection if VCF data starts with =, +, - or @.</comment>

<file context>
@@ -0,0 +1,69 @@
+  const first = data[0];
+  if (!first) return "";
+  const headers = Object.keys(first);
+  const escape = (str: string) => `"${str.replace(/"/g, '""')}"`;
+  const rows = data.map((row) => headers.map((h) => escape(row[h] || "")).join(","));
+  return [headers.join(","), ...rows].join("\n");
</file context>

[cubic-dev-ai]

P1: CSV headers are derived only from the first contact, so fields present only in later contacts are omitted and their values are dropped from the CSV output.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/converters/vcf.ts, line 51:

<comment>CSV headers are derived only from the first contact, so fields present only in later contacts are omitted and their values are dropped from the CSV output.</comment>

<file context>
@@ -0,0 +1,69 @@
+  if (!data.length) return "";
+  const first = data[0];
+  if (!first) return "";
+  const headers = Object.keys(first);
+  const escape = (str: string) => `"${str.replace(/"/g, '""')}"`;
+  const rows = data.map((row) => headers.map((h) => escape(row[h] || "")).join(","));
</file context>

Suggested change

	const headers = Object.keys(first);
	const headers = Array.from(new Set(data.flatMap((row) => Object.keys(row))));

[cubic-dev-ai]

P1: VCF parsing ignores vCard parameters and folded lines, dropping FN/N values and truncating long fields

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/converters/vcf.ts, line 28:

<comment>VCF parsing ignores vCard parameters and folded lines, dropping FN/N values and truncating long fields</comment>

<file context>
@@ -0,0 +1,69 @@
+        if (colonIndex === -1) continue;
+        const key = line.slice(0, colonIndex).trim();
+        const value = line.slice(colonIndex + 1).trim();
+        if (key === "FN") {
+          contact["Full Name"] = value;
+        } else if (key === "N") {
</file context>

[C4illin]

Nice work! Everything seems to work with the vCards I have tested. Should I merge it?

[kunal763]

Yeah I think everything is good from my end