perf: replace 8 filter passes with single-pass message categorization

[MintCollector]

Summary

• Replaces 8 separate .filter() calls in SessionParser.processMessages() with a single for...of loop and switch statement
• Uses else if for isParsedRealUserMessage / isParsedInternalUserMessage since they are mutually exclusive (checked by isMeta)
• Reduces array iterations from 8× to 1× per session parse

Addresses #95

Test plan

• All 653 tests pass
• Typecheck clean
• Lint clean
• Production build succeeds
• Verified realUser and internalUser are mutually exclusive via isMeta flag

🤖 Generated with Claude Code

Summary by CodeRabbit

• Refactor
  • Optimized internal message processing efficiency in the session handler through streamlined classification operations.

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a significant performance enhancement to the message processing logic within the SessionParser. By consolidating multiple array filtering operations into a single iteration, it streamlines the categorization of messages, reducing redundant computations and improving overall efficiency. This change directly addresses a known performance bottleneck, making the session parsing process faster and more resource-friendly.

Highlights

• Performance Optimization: Replaced 8 separate .filter() calls in SessionParser.processMessages() with a single for...of loop and switch statement for message categorization.
• Conditional Logic: Implemented else if for isParsedRealUserMessage / isParsedInternalUserMessage checks, leveraging their mutual exclusivity.
• Efficiency Improvement: Reduced array iterations from 8x to 1x per session parse, significantly improving processing efficiency.

Changelog

• src/main/services/parsing/SessionParser.ts
  • Refactored message categorization from multiple filter calls to a single for...of loop with a switch statement.
  • Optimized realUser and internalUser message checks using else if conditions within the single loop.
  • Integrated sidechain and main message separation into the primary iteration, further reducing array traversals.

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[gemini-code-assist]

Code Review

This is a great performance improvement, replacing 8 filter passes with a single loop. This significantly reduces the number of iterations over the messages array. I've left one suggestion for a minor additional optimization within the loop.

[gemini-code-assist]

Since this PR is focused on performance, we can make a small additional optimization here.

Given that we are inside case 'user', isParsedInternalUserMessage(m) is equivalent to checking m.isMeta. Also, isParsedRealUserMessage(m) will only be true if !m.isMeta.

We can reorder the checks to be slightly more efficient by checking m.isMeta directly. This avoids one function call to isParsedRealUserMessage when m.isMeta is true, and replaces the call to isParsedInternalUserMessage with a direct property access.

Suggested change

	if (isParsedRealUserMessage(m)) {
	byType.realUser.push(m);
	} else if (isParsedInternalUserMessage(m)) {
	byType.internalUser.push(m);
	}
	if (m.isMeta) {
	byType.internalUser.push(m);
	} else if (isParsedRealUserMessage(m)) {
	byType.realUser.push(m);
	}

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: a0e7e04f-1811-437a-8775-31a38f55634d

📥 Commits

Reviewing files that changed from the base of the PR and between f23c581 and 4092fa1.

📒 Files selected for processing (1)

• src/main/services/parsing/SessionParser.ts

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📝 Walkthrough

Walkthrough

Refactored processMessages in SessionParser.ts to classify messages using a single-pass loop with type-based categorization, replacing the previous eight separate filter passes while maintaining the same return structure.

Changes

Cohort / File(s)	Summary
Message Processing Optimization src/main/services/parsing/SessionParser.ts	Reworked processMessages to use iterative categorization via switch statement on message type instead of multiple filter passes. Consolidated population of byType categories (user, realUser, internalUser, assistant, system, other) and message separation (sidechainMessages, mainMessages) into single loop.

Suggested labels

feature request

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