Erupe/docs/technical-debt.md

Erupe Technical Debt & Suggested Next Steps

Last updated: 2026-02-22

This document tracks actionable technical debt items discovered during a codebase audit. It complements anti-patterns.md (which covers structural patterns) by focusing on specific, fixable items with file paths and line numbers.

Table of Contents

• High Priority
  • 1. Broken game features (gameplay-impacting TODOs)
  • 2. Test gaps on critical paths
• Medium Priority
  • 3. Logging anti-patterns
• Low Priority
  • 4. CI updates
• Completed Items
• Suggested Execution Order

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High Priority

1. Broken game features (gameplay-impacting TODOs)

These TODOs represent features that are visibly broken for players.

Location	Issue	Impact
model_character.go:88,101,113	TODO: fix bookshelf data pointer for G10-ZZ, F4-F5, and S6 versions	Wrong pointer corrupts character save reads for three game versions. Offset analysis shows all three are off by exactly 14810 vs the consistent delta pattern of other fields — but needs validation against actual save data.
handlers_achievement.go:125	TODO: Notify on rank increase — always returns false	Achievement rank-up notifications are silently suppressed. Requires understanding what MhfDisplayedAchievement (currently an empty handler) sends to track "last displayed" state.
handlers_guild_info.go:443	TODO: Enable GuildAlliance applications — hardcoded true	Guild alliance applications are always open regardless of setting. Needs research into where the toggle originates.
handlers_session.go:394	TODO(Andoryuuta): log key index off-by-one	Known off-by-one in log key indexing is unresolved
handlers_session.go:535	TODO: This case might be <=G2	Uncertain version detection in switch case
handlers_session.go:698	TODO: Retail returned the number of clients in quests	Player count reported to clients does not match retail behavior

2. Test gaps on critical paths

Handler files with no test file (7 remaining):

File	Priority	Reason
handlers_commands.go	HIGH	Admin command system
handlers_data_paper.go	MEDIUM	Daily paper data
handlers_seibattle.go	MEDIUM	Sei battle system
handlers_scenario.go	LOW	Mostly complete, uses repo
handlers_distitem.go	LOW	Distribution items
handlers_guild_mission.go	LOW	Guild missions
handlers_kouryou.go	LOW	Kouryou system

Repository files with no store-level test file (17 total):

repo_achievement.go, repo_cafe.go, repo_distribution.go, repo_diva.go, repo_festa.go, repo_gacha.go, repo_goocoo.go, repo_house.go, repo_mail.go, repo_mercenary.go, repo_misc.go, repo_rengoku.go, repo_scenario.go, repo_session.go, repo_shop.go, repo_stamp.go, repo_tower.go

These are validated indirectly through mock-based handler tests but have no SQL-level integration tests.

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Medium Priority

3. Logging anti-patterns

a) fmt.Sprintf inside structured logger calls (6 sites): Fixed. All 6 sites now use zap.Uint32/zap.Uint8/zap.String structured fields instead of fmt.Sprintf.

b) 20+ silently discarded SJIS encoding errors in packet parsing: Fixed. All call sites now use SJISToUTF8Lossy() which logs decode errors at slog.Debug level.

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Low Priority

4. CI updates

• codecov-action@v4 could be updated to v5 (current stable) Fixed. Updated to codecov-action@v5.
• No coverage threshold is enforced — coverage is uploaded but regressions aren't caught

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Completed Items

Items resolved since the original audit:

#	Item	Resolution
3	Sign server has no repository layer	Fully refactored with repo_interfaces.go, repo_user.go, repo_session.go, repo_character.go, and mock tests. All 8 previously-discarded error paths are now handled.
4	Split repo_guild.go	Split from 1004 lines into domain-focused files: repo_guild.go (466 lines, core CRUD), repo_guild_posts.go, repo_guild_alliance.go, repo_guild_adventure.go, repo_guild_hunt.go, repo_guild_cooking.go, repo_guild_rp.go.
6	Inconsistent transaction API	All call sites now use BeginTxx(context.Background(), nil) with deferred rollback.
7	LoopDelay config has no Viper default	viper.SetDefault("LoopDelay", 50) added in config/config.go.
—	Monthly guild item claim (handlers_guild.go:389)	Now tracks per-character per-type monthly claims via stamps table.
—	Handler test coverage (4 files)	Tests added for handlers_session.go, handlers_gacha.go, handlers_plate.go, handlers_shop.go.
—	Entrance server raw SQL	Refactored to repository interfaces (repo_interfaces.go, repo_session.go, repo_server.go).
—	Guild daily RP rollover (handlers_guild_ops.go:148)	Implemented via lazy rollover in handlers_guild.go:110-119 using RolloverDailyRP(). Stale TODO removed.
—	Typos (sys_session.go, handlers_session.go)	"For Debuging" and "offical" typos already fixed in previous commits.
—	db != nil guard (handlers_session.go:322)	Investigated — this guard is intentional. Test servers run without repos; the guard protects the entire logout path from nil repo dereferences. Not a leaky abstraction.

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Suggested Execution Order

Based on remaining impact:

1. Add tests for handlers_commands.go — highest-risk remaining untested handler (admin commands)
2. Fix bookshelf data pointer (model_character.go) — corrupts saves for three game versions (needs save data validation)
3. Fix achievement rank-up notifications (handlers_achievement.go:125) — needs protocol research on MhfDisplayedAchievement
4. Add coverage threshold to CI — prevents regressions