Erupe/docs/technical-debt.md

Erupe Technical Debt & Suggested Next Steps

Last updated: 2026-02-27

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	Tracker
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.	#164
handlers_achievement.go:117	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.	#165
handlers_guild_info.go:443	TODO: Enable GuildAlliance applications — hardcoded true	Guild alliance applications are always open regardless of setting. Fixed. Added recruiting column to guild_alliances, wired OperateJoint actions 0x06/0x07, reads from DB.	#166
handlers_session.go:410	TODO(Andoryuuta): log key index off-by-one	Known off-by-one in log key indexing is unresolved	#167
handlers_session.go:551	TODO: This case might be <=G2	Uncertain version detection in switch case	#167
handlers_session.go:714	TODO: Retail returned the number of clients in quests	Player count reported to clients does not match retail behavior	#167
msg_mhf_add_ud_point.go:28	TODO: Parse is a stub — field meanings unknown	UD point packet fields unnamed, Build not implemented	#168

2. Test gaps on critical paths

All handler files now have test coverage.

Repository files with no store-level test file (17 total): Fixed. All 20 repo source files now have corresponding _test.go files. The split guild files (repo_guild_adventure.go, repo_guild_alliance.go, etc.) are covered by repo_guild_test.go. These are mock-based unit tests; SQL-level integration tests against a live database remain a future goal.

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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) Removed. Replaced with local go tool cover threshold check (no Codecov account needed).
• No coverage threshold is enforced — coverage is uploaded but regressions aren't caught Fixed. CI now fails if total coverage drops below 50% (current: ~58%).

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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.
—	Handler test coverage (handlers_commands.go)	62 tests covering all 12 commands, disabled-command gating, op overrides, error paths, raviente with semaphore, course enable/disable/locked, reload with players/objects.
—	Handler test coverage (handlers_data_paper.go)	20 tests covering all DataType branches (0/5/6/gift/>1000/unknown), ACK payload structure, earth succeed entry counts, timetable content, serialization round-trips, and paperGiftData table integrity.
—	Handler test coverage (5 files)	Tests added for handlers_seibattle.go (9 tests), handlers_kouryou.go (7 tests), handlers_scenario.go (6 tests), handlers_distitem.go (8 tests), handlers_guild_mission.go (5 tests in coverage5).
—	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.
2	Repo test coverage (17 files)	All 20 repo source files now have _test.go files with mock-based unit tests.

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Suggested Execution Order

Based on remaining impact:

1. Add tests for handlers_commands.go — Done. 62 tests covering all 12 commands (ban, timer, PSN, reload, key quest, rights, course, raviente, teleport, discord, playtime, help), disabled-command gating, op overrides, error paths, and initCommands.
2. Fix bookshelf data pointer (#164) — corrupts saves for three game versions (needs save data validation)
3. Fix achievement rank-up notifications (#165) — needs protocol research on MhfDisplayedAchievement
4. Add coverage threshold to CI — Done. 50% floor enforced via go tool cover in CI; Codecov removed.
5. Fix guild alliance toggle (#166) — Done. recruiting column + OperateJoint allow/deny actions + DB toggle
6. Fix session handler retail mismatches (#167) — log key off-by-one, version boundary, player count
7. Reverse-engineer MhfAddUdPoint fields (#168) — needs packet captures