From 07c755800794cd89cc3b1907ccaf2729e6c08d25 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Enzo=20NAUT=C3=89?= <hey@enzonaute.me>
Date: Sat, 4 Apr 2026 03:13:01 +0200
Subject: [PATCH] fix: deduplicate message hashes across files, not just within
 each file

parseClaudeFile() resets its seenKeys set per file. Claude Code logs
subagent messages to both the parent session JSONL and the subagent's
own JSONL under <session>/subagents/. Since both files share the same
messageId:requestId pairs, per-file dedup misses the cross-file
duplicates and inflates the totals.

On a real dataset (30 days, 538 files):
  - per-file dedup:  7.98B tokens (current behavior)
  - global dedup:    2.59B tokens (correct, matches ccusage)
  - ratio: 3.08x overcounting

Fix: pass the seenKeys set through ClaudeScanState so it accumulates
across all files in a single scan pass. The new existingSeenKeys
parameter defaults to [] so existing call sites and tests are
unaffected.
---
 .../CostUsage/CostUsageScanner+Claude.swift   | 22 ++++++++++++++-----
 .../Vendored/CostUsage/CostUsageScanner.swift |  1 +
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner+Claude.swift b/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner+Claude.swift
index 3c747bb1d..4c8256521 100644
--- a/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner+Claude.swift
+++ b/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner+Claude.swift
@@ -35,12 +35,15 @@ extension CostUsageScanner {
         fileURL: URL,
         range: CostUsageDayRange,
         providerFilter: ClaudeLogProviderFilter,
-        startOffset: Int64 = 0) -> ClaudeParseResult
+        startOffset: Int64 = 0,
+        existingSeenKeys: Set<String> = []) -> ClaudeParseResult
     {
         var days: [String: [String: [Int]]] = [:]
-        // Track seen message+request IDs to deduplicate streaming chunks within a JSONL file.
+        // Track seen message+request IDs to deduplicate streaming chunks.
         // Claude emits multiple lines per message with cumulative usage, so we only count once.
-        var seenKeys: Set<String> = []
+        // Uses existingSeenKeys from prior files to also deduplicate across files
+        // (e.g. subagent logs that duplicate parent session entries).
+        var seenKeys = existingSeenKeys
 
         struct ClaudeTokens: Sendable {
             let input: Int
@@ -133,7 +136,7 @@ extension CostUsageScanner {
                 add(dayKey: dayKey, model: model, tokens: tokens)
             })) ?? startOffset
 
-        return ClaudeParseResult(days: days, parsedBytes: parsedBytes)
+        return ClaudeParseResult(days: days, parsedBytes: parsedBytes, seenKeys: seenKeys)
     }
 
     private static let vertexProviderKeys: Set<String> = [
@@ -263,6 +266,9 @@ extension CostUsageScanner {
         var touched: Set<String>
         let range: CostUsageDayRange
         let providerFilter: ClaudeLogProviderFilter
+        /// Shared across all files in a scan pass to deduplicate messages
+        /// that appear in both a parent session JSONL and its subagent files.
+        var globalSeenKeys: Set<String> = []
 
         init(cache: CostUsageCache, range: CostUsageDayRange, providerFilter: ClaudeLogProviderFilter) {
             self.cache = cache
@@ -296,7 +302,9 @@ extension CostUsageScanner {
                     fileURL: url,
                     range: state.range,
                     providerFilter: state.providerFilter,
-                    startOffset: startOffset)
+                    startOffset: startOffset,
+                    existingSeenKeys: state.globalSeenKeys)
+                state.globalSeenKeys = delta.seenKeys
                 if !delta.days.isEmpty {
                     Self.applyFileDays(cache: &state.cache, fileDays: delta.days, sign: 1)
                 }
@@ -317,7 +325,9 @@ extension CostUsageScanner {
         let parsed = Self.parseClaudeFile(
             fileURL: url,
             range: state.range,
-            providerFilter: state.providerFilter)
+            providerFilter: state.providerFilter,
+            existingSeenKeys: state.globalSeenKeys)
+        state.globalSeenKeys = parsed.seenKeys
         let usage = Self.makeFileUsage(
             mtimeUnixMs: mtimeMs,
             size: size,
diff --git a/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner.swift b/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner.swift
index f4a3ba8bb..027eba96a 100644
--- a/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner.swift
+++ b/Sources/CodexBarCore/Vendored/CostUsage/CostUsageScanner.swift
@@ -47,6 +47,7 @@ enum CostUsageScanner {
     struct ClaudeParseResult {
         let days: [String: [String: [Int]]]
         let parsedBytes: Int64
+        let seenKeys: Set<String>
     }
 
     static func loadDailyReport(