gogobee/gogobee_legacy_migration.md

GogoBee — Legacy Adventure → D&D Engine Migration Plan

Companion to: gogobee_dnd_design_doc.md, gogobee_expedition_system.md, gogobee_resource_combat_integration.md Version: 0.1 (planning draft) Status: Pre-implementation — scoping Branch: adv-2.0

---

0. Why this doc exists

Phase R (resource/combat integration) shipped the new harvest/combat surface and gated the player-facing legacy daily-loop dispatch. The internal helpers (resolveAdvAction, advEligibleLocations, AdvLocation tier data, AdventureCharacter, CombatLevel, combat_engine.go) are still alive because non-deprecated subsystems consume them: arena, co-op dungeons, babysit/scheduler, hospital, rival, masterwork, pets, housing, mortgage, twinbee morning DM.

This doc inventories every surviving caller and lays out a phased deletion path. The endgame is: AdventureCharacter deleted, CombatLevel field gone, combat_engine.go removed, combat_bridge.go removed, branching dungeon paths become buildable on a clean schema.

Non-goals. This is not a redesign. We are not adding features during the migration. New mechanics (branching paths, multi-region expansions, new arena formats) are sequenced after L5 teardown lands.

---

1. Inventory — what's still on the legacy engine

Subsystem	Files	LOC	AdvCharacter coupling	CombatLevel coupling	D&D parallel	Risk
Babysit/scheduler	adventure_babysit.go, adventure_scheduler.go	1,169	mutates: CombatXP, Alive, ActionTakenToday	reads	none (auto-actions)	low
Arena	adventure_arena*.go (4 files)	1,228	mutates: Alive, ArenaWins/Losses, CombatXP	gates tier, scales rewards	dnd_zone_combat.go	high
Co-op dungeons	coop_dungeon*.go (9 files)	4,027	reads-only (minLevel gate, liability)	gates participation	dnd_expedition_combat.go	medium
Hospital	adventure_hospital.go	288	mutates: Alive, HospitalVisits	cost = level × 25k/125k	none	low
Rival	adventure_rival.go	866	mutates: RivalPool, CombatXP	unlock at L5, stake calc	none	medium
Masterwork	adventure_masterwork.go	543	reads equip, no char mutation	none	none	low
Pets	adventure_pets.go	448	mutates pet fields on AdvCharacter	none	none	low
Housing/mortgage	adventure_housing.go, adventure_mortgage.go	922	mutates House* fields	none	none	low
TwinBee/render	adventure_render.go, adventure_twinbee.go	1,472	reads stats; simulator calls resolveAdvAction	reads	none	low
Combat bridge	combat_bridge.go	363	translation layer	—	—	(delete)

Source of truth: AdventureCharacter is defined at adventure_character.go:27 (76 fields). DnDCharacter at dnd.go:152.

Live resolveAdvAction callers (post-R1): adventure_babysit.go:349, adventure_twinbee.go:135 (simulator).

---

2. Architectural decision — char unification strategy

Three options were considered:

A. Big-bang field merge. Move every surviving AdvCharacter field onto DnDCharacter, then s/AdventureCharacter/DnDCharacter/g. Rejected: unsafe, no incremental landing, breaks every test for one PR.

B. Two-character coexistence forever. Keep both, route by feature. Rejected: this is what we have now; doesn't actually retire anything.

C. Phased subsystem migration with shared "extra" record. ✅ Chosen. Each subsystem is migrated to read/write D&D state where there's a parallel, and to a new player_meta table for fields that don't fit on a character (HouseTier, RivalPool, ArenaWins, BabysitActive, MistyLastSeen, etc.). When all subsystems are migrated, AdvCharacter is deleted in a single L5 commit.

The player_meta table is the holding pen for non-stat per-user state that's currently squatting on AdvCharacter. It's not a redesign — it's a structural move so the deletion can happen cleanly.

2.1 player_meta schema (proposed)

Naming note. New tables/types in this migration deliberately avoid the dnd_ prefix used by older code (legal/trademark exposure flagged by user). Existing dnd_* symbols stay in place — only new surface uses neutral names.

CREATE TABLE player_meta (
    user_id            TEXT PRIMARY KEY,
    -- arena
    arena_wins         INTEGER NOT NULL DEFAULT 0,
    arena_losses       INTEGER NOT NULL DEFAULT 0,
    invasion_score     INTEGER NOT NULL DEFAULT 0,
    -- rival
    rival_pool         INTEGER NOT NULL DEFAULT 0,
    rival_unlocked_notified INTEGER NOT NULL DEFAULT 0,
    -- housing
    house_tier         INTEGER NOT NULL DEFAULT 0,
    house_loan_balance INTEGER NOT NULL DEFAULT 0,
    house_loan_frozen  INTEGER NOT NULL DEFAULT 0,
    house_missed_payments INTEGER NOT NULL DEFAULT 0,
    house_autopay      INTEGER NOT NULL DEFAULT 0,
    house_current_rate REAL NOT NULL DEFAULT 0,
    -- pets
    pet_type           TEXT NOT NULL DEFAULT '',
    pet_name           TEXT NOT NULL DEFAULT '',
    pet_xp             INTEGER NOT NULL DEFAULT 0,
    pet_level          INTEGER NOT NULL DEFAULT 0,
    pet_armor_tier     INTEGER NOT NULL DEFAULT 0,
    pet_flags_json     TEXT NOT NULL DEFAULT '{}',  -- chased_away/reactivated/arrived/morning_defense/etc
    -- npcs
    misty_last_seen    INTEGER,
    arina_last_seen    INTEGER,
    misty_buff_expires INTEGER,
    misty_debuff_expires INTEGER,
    arina_buff_expires INTEGER,
    misty_encounter_count INTEGER NOT NULL DEFAULT 0,
    misty_donated_count INTEGER NOT NULL DEFAULT 0,
    misty_roll_target  INTEGER NOT NULL DEFAULT 0,
    arina_roll_target  INTEGER NOT NULL DEFAULT 0,
    -- babysit
    babysit_active     INTEGER NOT NULL DEFAULT 0,
    babysit_expires_at INTEGER,
    babysit_skill_focus TEXT NOT NULL DEFAULT '',
    auto_babysit       INTEGER NOT NULL DEFAULT 0,
    auto_babysit_focus TEXT NOT NULL DEFAULT '',
    -- hospital / death
    hospital_visits    INTEGER NOT NULL DEFAULT 0,
    last_death_date    TEXT NOT NULL DEFAULT '',
    death_source       TEXT NOT NULL DEFAULT '',
    death_location     TEXT NOT NULL DEFAULT '',
    last_pardon_used   INTEGER,
    death_reprieve_last INTEGER,
    -- streaks / chores
    current_streak     INTEGER NOT NULL DEFAULT 0,
    best_streak        INTEGER NOT NULL DEFAULT 0,
    last_action_date   TEXT NOT NULL DEFAULT '',
    grudge_location    TEXT NOT NULL DEFAULT '',
    holiday_action_taken INTEGER NOT NULL DEFAULT 0,
    streak_decayed     INTEGER NOT NULL DEFAULT 0,
    -- shop / drops
    masterwork_drops_received INTEGER NOT NULL DEFAULT 0,
    treasures_locked   INTEGER NOT NULL DEFAULT 0,
    pet_supply_shop_unlocked INTEGER NOT NULL DEFAULT 0,
    pet_level_10_date  TEXT NOT NULL DEFAULT '',
    thom_animal_line_fired INTEGER NOT NULL DEFAULT 0,
    -- chat / npc msg
    npc_msg_count      INTEGER NOT NULL DEFAULT 0,
    npc_msg_count_date TEXT NOT NULL DEFAULT '',
    robbie_visit_count INTEGER NOT NULL DEFAULT 0,
    crafts_succeeded   INTEGER NOT NULL DEFAULT 0
);

2.2 Stat mapping — AdvCharacter → DnDCharacter

Decisions locked in by user 2026-05-08:

• CombatLevel→Level: direct copy. CombatLevel doesn't carry semantic meaning beyond "starting Level for the new system." No compression formula. Players keep their numeric value as their D&D Level.
• CombatXP→XP: discarded. Players start fresh on the new XP track (CombatXP is not migrated). The Level set above is their floor; XP resets to 0 at that level's threshold.
• AdvEquipment: kept as-is. Stays at AdvEquipment type and adventure_equipment table. No rename to dnd_* (per naming guidance — see §2.0 callout above).

AdvCharacter	DnDCharacter destination	Notes
CombatLevel	Level	Direct copy on backfill; no formula.
CombatXP	—	Not migrated. XP starts at the floor of the new Level.
MiningSkill / ForagingSkill / FishingSkill	retained as new fields on DnDCharacter	These are skills, not class levels. Add MiningSkill/ForagingSkill/FishingSkill int to DnDCharacter; keep XP fields too.
Alive / DeadUntil	DnDCharacter HPCurrent==0 + DeadUntil	Need to add DeadUntil *time.Time to DnDCharacter.
Title	new field on DnDCharacter	Direct copy.
equipment (AdvEquipment)	stays at AdvEquipment / adventure_equipment	Type and table name unchanged. Read paths drop AdvCharacter unwrap; no rename pass.

2.3 CombatLevel retuning

Legacy CombatLevel scaled 1–50ish through grindy XP. D&D Level scales 1–20. Hospital/rival/co-op gates that read CombatLevel will be re-tuned to D&D Level brackets:

Legacy gate	New gate
Hospital cost = CombatLevel × 25k (or × 125k post-cap)	Level × 50k (or × 250k at L20+)
Rival unlock at CombatLevel ≥ 5	Rival unlock at Level ≥ 3
Arena tier brackets (every 10 CL)	Arena tier brackets (every 4 levels)
Co-op dungeon minLevel	Re-tune per dungeon (table in L3 section)

These thresholds are placeholders — final tuning happens during each phase based on playtest.

---

3. Phase L1 — Babysit & scheduler

Goal: Kill the last live resolveAdvAction caller. Auto-actions become expedition-aware.

Files touched: adventure_babysit.go, adventure_scheduler.go, adventure_twinbee.go (simulator), adventure_activities.go (delete resolveAdvAction + advEligibleLocations after callers gone).

Design:

• Babysit currently picks one of three skills (mining/foraging/fishing) and runs resolveAdvAction once a day for the user. The new flow:
  • If user has an active expedition → babysit attempts a single harvest action (!forage/!mine/!fish per skill focus) inside the user's current room. Goes through handleHarvestCmd headlessly with babysit:true flag so combat interrupts force-extract instead of running combat. (User isn't online; can't fight.)
  • If user has no active expedition → babysit posts a TwinBee nudge (one per real day, rate-limited to once/3d) suggesting !expedition start. No XP awarded.
• auto_babysit becomes "auto-harvest while expedition active." babysit_skill_focus carries through unchanged.
• adventure_twinbee.go:135 simulator (uses fake CombatLevel=35 character) — replace with a fixed flavor-only narration. The simulator was always fake; deleting the AdvCharacter dependency is mechanical.

Steps:

1. Add auto_babysit / babysit_* columns to player_meta (per §2.1) — migration + read/write helpers.
2. Add babysit:true flag to harvest dispatch path; on combat-interrupt branches Standard/Elite/Patrol, force-extract the region run instead of entering combat. Test.
3. Rewrite babysitDo to call new harvest path. Remove resolveAdvAction call. Test (covers: active expedition, no expedition, harvest yields → inventory, combat interrupt force-extract).
4. Rewrite scheduler entrypoint analogously.
5. Replace twinbee simulator with static flavor.
6. Delete resolveAdvAction, advEligibleLocations, AdvActionResult, parseActivityLocation from adventure_activities.go. Audit for last callers via grep.
7. go test ./... && go vet.

Tests added: adventure_babysit_test.go (currently absent — create). Cases: babysit-with-expedition harvests, babysit-without-expedition nudges, combat-interrupt during babysit force-extracts cleanly, daily rate-limit holds.

Exit criteria:

• grep resolveAdvAction internal/plugin/ returns 0 hits.
• go test ./... clean.
• Production users with auto_babysit=true and an active expedition see harvest deposits, not legacy activity output.

Risk: Babysit users have a behavior change (now auto-harvests instead of always rolling). Announce in ADVENTURE_2.0_ANNOUNCEMENT.md.

---

4. Phase L2 — Arena (rebuild on Adventure 2.0 boss flow)

Decision (2026-05-08): Arena migrates to the Adventure 2.0 boss flow — the same staged narrative path zone bosses run through (resolveBossRoom in dnd_zone_cmd.go:630). Each arena fight is treated as a self-contained boss encounter: full combat log via RenderCombatLog, TwinBee mood lines on Nat20/Nat1, phase-two narration when the enemy crosses its PhaseTwoAt HP threshold, win/loss outcome blocks. Arena stops being "numbers vs numbers" and becomes a narrated event with the same texture as a zone boss room.

This is also the right shape because zone-boss plumbing (bestiary, mood events, phase transitions, kill records, loot drops) is already built and tested. We re-use it rather than re-implementing.

Files touched:

• adventure_arena.go — entrypoint, gating, payout. Heavy rewrite.
• adventure_arena_combat.go — round driver. Replaced by a call into runZoneCombat + a new arena-specific staged renderer (or direct re-use of the zone boss render — see step 4).
• adventure_arena_render.go — reads switch to DnDCharacter + player_meta.
• adventure_arena_monsters.go — deleted as standalone. Arena monsters are folded into the existing bestiary as boss-shaped entries (with PhaseTwoAt).
• adventure_arena_test.go — ported.
• New (small): adventure_arena_flavor.go — only if zone TwinBee pools don't cover arena context. Check existing adventure_flavor_*.go first per the reuse-flavor feedback rule before creating this file.

Design specifics:

• Arena monster definitions. Each existing ArenaMonster becomes a BestiaryEntry shape: {ID, Name, HP, AC, AB, DamageDie, CR, PhaseTwoAt, Tags}. Arena IDs are namespaced arena_<tier>_<slug> so they don't collide with zone bestiary IDs. Stored in a new arenaBosses map (still in adventure_arena_monsters.go if the file is kept; otherwise inlined). Tier brackets controlled by Arena tier (see below).

• Combat invocation. Arena round driver builds BossEncounter{Monster, PhaseTwoAt, ZoneIDForFlavor} and calls a small new function resolveArenaBoss(userID, encounter) that wraps the same runZoneCombat → RenderCombatLog → mood/phase-two lines flow as resolveBossRoom. Important: arena is not inside a zone, so we factor the staged-narration body out of resolveBossRoom into a shared helper renderBossOutcome(...) that both call sites use. (resolveBossRoom keeps its zone-specific glue: zone loot drop, applyBossDefeatThreat, abandonZoneRun. Arena keeps its glue: Arena win/loss counters, payout, no zone loot.)

• TwinBee flavor in arena. twinBeeLine(zoneID, ...) is keyed by zone; Arena passes a synthetic ZoneArena ID. Add ZoneArena to the zone enum and populate a small TwinBee mood/Nat20/Nat1/BossDeath/PlayerDeath pool — reuse existing pools where possible (per feedback_reuse_existing_flavor); only add new lines if the existing pools genuinely don't read right in arena context.

• Phase-two thresholds. Arena bosses get PhaseTwoAt defaults: tier 1–2 = no phase two (numeric drama only); tier 3 = 50% HP; tier 4–5 = 50% HP + a flavor barb. This gives arena fights a structural beat without overengineering.

• Tier gating. tierFromCombatLevel → tierFromLevel. Brackets:

  DnDCharacter.Level	Arena tier
  1–3	I (Pup)
  4–7	II (Pit)
  8–12	III (Crucible)
  13–17	IV (Coliseum)
  18–20	V (Apex)

• State. ArenaWins, ArenaLosses, InvasionScore move to player_meta (per §2.1). XP awards go through whatever the existing D&D XP path is (single source of truth — verify in dnd_sheet.go during implementation).

• Death. Arena death now flows through the same markAdventureDead(userID, "arena", arenaTierLabel) hook the zone boss path uses. Hospital revive (post-L4a) heals from this same state.

Steps:

1. Factor renderBossOutcome helper out of resolveBossRoom. Two callers post-extraction: zone boss path and (TBD) arena path. Smoke-test the zone boss path is unchanged via adventure_arena_test.go parity once arena lands on it.
2. Add ZoneArena ID + minimal TwinBee mood pools (reuse where possible).
3. Convert arena monsters to boss-shaped bestiary entries with PhaseTwoAt.
4. Build resolveArenaBoss(userID, encounter) calling runZoneCombat + renderBossOutcome. Wire into existing arena entrypoint in adventure_arena.go.
5. Migrate ArenaWins/Losses/InvasionScore to player_meta. Dual-write per §11.
6. Swap render reads to DnDCharacter + player_meta.
7. Port tierFromCombatLevel → tierFromLevel with new brackets.
8. Port adventure_arena_test.go. Add a new test asserting arena win surfaces the staged combat log + TwinBee BossDeath line.
9. Drop AdvCharacter imports from arena files. DEFERRED (2026-05-09): blocked on DisplayName migration (L4f-prep, see §7) plus L4 hospital/pets/XP work. Arena code still needs char.DisplayName (stats DM, T5/helm announces, render), char.PetName (pet-recovery game-room msg), char.DeathReprieveLast, char.CombatXP, char.Alive/transitionDeath. Counter dual-writes to char.ArenaWins/Losses/InvasionScore could be dropped now (player_meta is source of truth post-step 6), but the surrounding loadAdvCharacter/saveAdvCharacter calls stay for the other fields, so step 9's exit grep can't pass at L2 time. Revisit after DisplayName migration ships and L4 (hospital/pets/render) lands.
10. go test ./... && go vet.

Feature flag. Originally planned an ARENA_BOSS_FLOW=1 soak. Cancelled 2026-05-09: shipped no-flag, no legacy fallback. The legacy runArenaCombat / RenderCombatLogArena / renderArenaCombatFinalMessage / renderArenaOutcome / arenaWin/LoseCloser paths were deleted in the same commit. Boss-flow errors surface to the player and abort the round rather than falling back.

Exit criteria:

• grep -l 'AdventureCharacter\|CombatLevel\|combat_engine' internal/plugin/adventure_arena*.go empty. Deferred with step 9 — see note above. The grep will only clear once DisplayName migration + L4 (hospital/pets/XP/render) ship; L2 closes without it.
• Arena win produces a staged combat log + TwinBee BossDeath line + payout, just like a zone boss.
• Arena loss produces a TwinBee PlayerDeath line + arena death flag, no zone-run side effects.
• Existing arena DB rows readable; ArenaWins backfill from AdvCharacter into player_meta (§8).

Risk:

• D&D combat is swingier than legacy CombatPower; tune HP/AC tables against in-flight playtest data (no flag soak — legacy path is gone).
• Refactoring resolveBossRoom to extract renderBossOutcome could regress zone bosses. Mitigate: do the extraction in step 1 alone, ship it, run a full zone-boss test pass before continuing to step 2.

---

5. Phase L3 — Co-op dungeons (DELETION, not migration) — SHIPPED 2026-05-09

Decision (2026-05-08): Drop co-op dungeons entirely. Do not migrate. The user has a different design in mind for the future co-op slot; the current implementation is being retired wholesale.

What shipped (2026-05-09):

• 11 coop_*.go files deleted (no coop_dungeon_balance.go ever existed on disk — only coop_dungeon_balance_test.go).
• internal/plugin/cleanup_l3.go added: on every startup, cancels any coop_dungeon_runs left in open/active, refunds coop_dungeon_members.total_contributed and unsettled coop_dungeon_bets via EuroPlugin.Credit. Idempotent via per-run status-guarded UPDATE — only the writer that flips status to cancelled performs the refund for that run, so a crashed-then-restarted process can't double-credit. Tables left intact for historical querying; SQL drop deferred to a future GOGOBEE_COOP_PURGE pass.
• adventure.go: stripped !coop dispatch, coopTicker goroutine, startup lockCoopCombatActions call, !coop help line, ticker comment. Replaced startup hook with closeAndRefundLegacyCoopRuns(p.euro).
• adventure_scheduler.go: removed activeCoopMemberSet load + skip branch and post-reset lockCoopCombatActions call.
• adventure_render.go: removed renderCoopTeaser, pickCoopTeaserCandidate, the loadCoopRunForUser block, and the in-coop combat-locked status line. Replaced with a temporary closure announcement in the morning DM ("Co-op dungeons closed for now — !expedition is the way forward; a better co-op design is on the way."). Marked with a TODO to remove after 2026-05-16.
• adventure_followups_test.go: removed TestPickCoopTeaserCandidate_SkipsLeader.

Exit criteria — met:

• grep -rn 'coop_dungeon\|CoopDungeon' internal/plugin/ --include='*.go' returns only the cleanup migration in cleanup_l3.go and a startup hook in adventure.go — no live system code references.
• go vet ./... clean.
• go test ./... clean.

Open follow-ups:

• Remove the morning-DM closure announcement after 2026-05-16 (one-week soak).
• Future GOGOBEE_COOP_PURGE pass drops coop_dungeon_runs/_members/_events/_bets/_gifts tables and the cleanup_l3.go startup hook.

---

6. Phase L4 — Stat/perk gates

Goal: Hospital, rival, masterwork, pets, housing, mortgage all read DnDCharacter + player_meta exclusively. AdvCharacter still exists but is unreferenced outside its own file.

6.1 L4a — Hospital

• adventure_hospital.go: cost formula CombatLevel × 25k → Level × 50k. HospitalVisits → player_meta. Revive flips DnDCharacter HP from 0 → full instead of Alive=true.

Status (2026-05-09): SHIPPED on adv-2.0.

• player_meta.hospital_visits column added via columnMigration in internal/db/db.go.
• hospitalCostsForUser(char) returns (before, after) using DnDCharacter.Level × 50k (5× before insurance), with a dndLevelFromCombatLevel fallback when no D&D row exists yet. Replaces the inline CombatLevel × {125k,25k} math at all three sites (handleHospitalCmd, resolveHospitalPay, sendHospitalAd).
• loadHospitalVisits(userID) reads player_meta.hospital_visits → falls back to adventure_characters.hospital_visits during soak.
• upsertPlayerMetaHospitalVisits(userID, visits) dual-writes the post-revive count alongside saveAdvCharacter.
• backfillPlayerMetaHospitalVisits() runs on every Init; idempotent (only fills zero rows so dual-writes survive re-runs).
• Revive (paid + on-demand + race-after-timer-expired) now also restores DnDCharacter.HPCurrent = HPMax via LoadDnDCharacter / SaveDnDCharacter. char.Alive=true still flips during soak — other systems (arena, scheduler) still read Alive and migrate later.
• Tests: TestPlayerMetaHospitalVisitsBackfill_Idempotent, TestLoadHospitalVisits_FallsBackToAdvCharacter, TestUpsertPlayerMetaHospitalVisits_RoundTrip (skip without prod DB, matching the L2/L4f-prep pattern).

6.2 L4b — Rival

• adventure_rival.go: unlock at Level ≥ 3 (was CombatLevel ≥ 5). RivalPool → player_meta. Duel combat already uses combat_engine — port to simulateCombat here too (small extra step). Correction (2026-05-09): rival duel combat is RPS, not combat_engine — no combat-engine port needed.
• Move rival flavor into existing adventure_flavor_rival.go — no new file.

Status (2026-05-09): SHIPPED on adv-2.0.

• player_meta.rival_pool + player_meta.rival_unlocked_notified columns added via columnMigration in internal/db/db.go.
• New rivalMinLevel = 3 (was rivalMinCombatLevel = 5). Stake formula (level / 3) * 1000 (was (combatLevel / 5) * 1000) — same magnitude at the unlock threshold (Level 3 → €1000 mirrors legacy CL5 → €1000), tops out around €6000 at Level 20. Tunable later.
• rivalLevelForUser(char) reads DnDCharacter.Level with dndLevelFromCombatLevel(char.CombatLevel) fallback when no D&D row exists yet — mirrors hospitalCostsForUser shape.
• checkRivalPoolUnlock now reads D&D level, dual-writes RivalPool / RivalUnlockedNotified to player_meta via upsertPlayerMetaRivalState. Read sites flipped to loadRivalState(userID) in selectRivalPair, handleRivalsCmd, and the morning-DM rival status in adventure_render.go.
• loadRivalState(userID) reads player_meta → falls back to adventure_characters.rival_pool / rival_unlocked_notified during soak.
• backfillPlayerMetaRivalState() runs on every Init; idempotent (only fills rows whose rival columns are still zero, so dual-writes survive re-runs).
• Tests: TestPlayerMetaRivalStateBackfill_Idempotent, TestLoadRivalState_FallsBackToAdvCharacter, TestUpsertPlayerMetaRivalState_RoundTrip (skip without prod DB, matching the L4a/L4f-prep pattern).
• go vet ./... + go test ./... clean.

6.3 L4c — Masterwork

• adventure_masterwork.go: no AdvCharacter mutations today; only equipment reads. Port advMasterworkSkillBonus to take *DnDCharacter (skill fields added in §2.2). Correction (2026-05-09): advMasterworkSkillBonus already takes (equip, activity) — no char param to port. MasterworkDropsReceived → player_meta.

Status (2026-05-09): SHIPPED on adv-2.0.

• player_meta.masterwork_drops_received column added via columnMigration in internal/db/db.go.
• checkMasterworkDrop signature dropped its char *AdventureCharacter param. First-drop detection now reads via loadMasterworkDrops(userID); counter writes go through upsertPlayerMetaMasterworkDrops and dual-write to AdvCharacter.MasterworkDropsReceived via loadAdvCharacter + saveAdvCharacter during soak.
• loadMasterworkDrops(userID) reads player_meta → falls back to adventure_characters.masterwork_drops_received during soak (mirrors loadHospitalVisits shape).
• backfillPlayerMetaMasterworkDrops() runs on every Init; idempotent (only fills rows whose masterwork_drops_received is still zero).
• Note: checkMasterworkDrop itself is currently dead code (Phase R deprecated its only caller, the legacy daily-loop). The migration still ports the field so the column moves cleanly when future zone integration re-wires the drop hook.
• Tests: TestPlayerMetaMasterworkDropsBackfill_Idempotent, TestLoadMasterworkDrops_FallsBackToAdvCharacter, TestUpsertPlayerMetaMasterworkDrops_RoundTrip.
• go vet ./... + go test ./... clean.
• Exit criterion: grep 'AdventureCharacter\|CombatLevel' internal/plugin/adventure_masterwork.go is empty.

6.4 L4d — Pets

• adventure_pets.go: pet fields move from AdvCharacter to player_meta (see §2.1 pet_* columns). Pet combat hooks (PetMorningDefense, pet damage rolls) target DnDCharacter HP.

Status (2026-05-09): SHIPPED on adv-2.0 (column + dual-write only; reader flip deferred — see note).

• player_meta gains pet_type, pet_name, pet_xp, pet_level, pet_armor_tier, pet_flags_json, pet_supply_shop_unlocked, pet_level_10_date via columnMigration in internal/db/db.go. The four flags (arrived, chased_away, reactivated, morning_defense) serialize as a single JSON column to avoid a four-bool ALTER train on each future flag addition.
• New helpers in player_meta.go: PetState struct, upsertPlayerMetaPetState(userID, PetState), loadPetState(userID) (player_meta canonical, falls back to AdvCharacter when pet_type is empty), backfillPlayerMetaPetState() (idempotent — copies rows whose player_meta pet_type is still default empty), and petStateFromAdvChar(*AdventureCharacter) for the dual-write projection.
• Dual-writes wired at every pet mutation site: resolvePetArrival (chase), resolvePetName (adopt), petMidnightCheck (supply-shop unlock), runBabysitDailyTrickle save in scheduler, morning PetMorningDefense set, and mistyReactivatePet save in adventure_npcs.go.
• petGrantXP (in adventure_pets.go) is currently dead code — only exercised by tests; once the legacy daily-loop XP path is rewired by Phase R/zone integration, that caller will need to add a dual-write at its save site.
• Backfill: backfillPlayerMetaPetState() runs on every Init; idempotent (only fills rows whose pet_type is still empty).
• Tests: TestPlayerMetaPetStateBackfill_Idempotent, TestLoadPetState_FallsBackToAdvCharacter, TestUpsertPlayerMetaPetState_RoundTrip in player_meta_test.go.
• go vet ./... + go test ./... clean.
• Reader flip deferred. The L4 exit criterion (grep 'AdventureCharacter\|CombatLevel' adventure_pets.go empty) is NOT met yet: adventure_pets.go's helpers (petGrantXP, petRollCombatActions, petRollDitchRecovery, petVictoryText, petDeathText, petShouldArrive, petMorningEvent, petCheckSupplyShopUnlock, mistyHousingHint, mistyReactivatePet) still take *AdventureCharacter because they're called from many external files (adventure_babysit.go, adventure_scheduler.go, adventure_npcs.go, combat_bridge.go, combat_stats.go, dnd_sheet.go, adventure_arena.go, adventure_character.go). Flipping these signatures is a cross-file refactor that can land after the soak window — at which point the helpers can take userID (and call loadPetState) and the call sites drop their *AdventureCharacter access. The DB-level migration (this step) is the prerequisite that unblocks that refactor.

Reader flip (cross-file signature port) SHIPPED 2026-05-09. All ten pet helpers in adventure_pets.go now take PetState (or *PetState for the test-only mutator petGrantXP) instead of *AdventureCharacter. mistyHousingHint takes (mistyEncounterCount, mistyDonatedCount int, house HouseState) — Misty NPC counters still live on AdvCharacter pending a later NPC phase. mistyReactivatePet returns bool (caller flips both AdvCharacter and PetState). PetState gained a HasPet() method mirroring AdventureCharacter.HasPet(). Call sites updated: adventure_scheduler.go (load PetState alongside HouseState in morning loop), adventure_npcs.go::resolveMisty (load PetState before reactivation check; pass NPC counters by value to the housing hint), combat_bridge.go::transitionDeath (now takes Pet PetState in DeathTransitionParams; arena caller in adventure_arena.go::resolveArenaDeath loads it; bridge no longer touches the DB so unit tests don't need DB init), and petMidnightCheck (loads PetState per char). Tests in adventure_pets_test.go and combat_bridge_test.go ported to construct PetState literals directly. Exit criterion now holds: grep 'AdventureCharacter\|CombatLevel' internal/plugin/adventure_pets.go is empty. go vet ./... && go test ./... clean.

6.5 L4e — Housing & mortgage

• adventure_housing.go, adventure_mortgage.go: HouseTier/loan fields → player_meta. houseHPBonus → applied to DnDCharacter.HPMax calculation (already a parallel hook in dnd_sheet.go's recomputeHPMax).
• Mortgage scheduler tick stays — only the field source changes.

Status (2026-05-09): SHIPPED on adv-2.0 (column + dual-write only; reader flip deferred — see note).

• player_meta gains house_tier, house_loan_balance, house_loan_frozen, house_missed_payments, house_autopay, house_current_rate via columnMigration in internal/db/db.go. Six columns (no JSON pack — bools and rate co-mutate with tier/balance at known sites).
• New helpers in player_meta.go: HouseState struct + HasHouse(), upsertPlayerMetaHouseState(userID, HouseState), loadHouseState(userID) (player_meta canonical when tier > 0 || loan_balance > 0, falls back to AdvCharacter otherwise), backfillPlayerMetaHouseState() (idempotent — only updates rows whose tier and loan_balance are both still zero), and houseStateFromAdvChar(*AdventureCharacter) for the dual-write projection.
• Dual-writes wired at every house mutation site in adventure_housing.go: handleThomBuy (full purchase + loan purchase), handleThomPayoff, handleThomPay (extra payment), handleThomAutopay, the four processMortgagePayments save paths (paid-off, success, missed-payment-freeze, missed-payment), and sendMortgageRateChangeDMs rate refresh.
• Backfill: backfillPlayerMetaHouseState() runs on every Init; idempotent (only fills rows whose house_tier and house_loan_balance are both still the default zero, and the legacy AdvCharacter row has either tier > 0 or loan > 0).
• Tests: TestPlayerMetaHouseStateBackfill_Idempotent, TestLoadHouseState_FallsBackToAdvCharacter, TestUpsertPlayerMetaHouseState_RoundTrip in player_meta_test.go (skip without prod DB, matching the L4d pattern).
• go vet ./... + go test ./... clean.
• Reader flip (read-only sites) SHIPPED 2026-05-09. dnd_rest.go long-rest housing eligibility, dnd_sheet.go housing-tier display, and adventure_pets.go::petShouldArrive/mistyHousingHint now read via loadHouseState(userID) (fallback to AdvCharacter inside the helper). petShouldArrive and mistyHousingHint gained a HouseState parameter; callers in adventure_scheduler.go and adventure_npcs.go load it. renderDnDSheet gained a HouseState parameter; test callers in dnd_subclass_test.go pass HouseState{}. Tests in adventure_pets_test.go updated to pass HouseState. go vet ./... && go test ./... clean.
• Reader flip in adventure_housing.go itself still deferred. Mutation paths (handleThomBuy, handleThomPayoff, handleThomPay, handleThomAutopay, processMortgagePayments, sendMortgageRateChangeDMs) read-then-write char.House* in place; flipping these is bundled with cutting the AdvCharacter writes (post-soak), not now.

6.6 L4f — TwinBee/render

• adventure_render.go: morning DM reads from DnDCharacter + player_meta. Coop teaser gating moves to DnDCharacter.Level.
• adventure_twinbee.go: simulator already addressed in L1. Remaining usage is read-only stat display — port to DnDCharacter.

Status (2026-05-09): SHIPPED on adv-2.0 (full reader-port).

• New helper dndLevelForUser(userID) in dnd.go: returns DnDCharacter.Level when present; falls back to dndLevelFromCombatLevel(adventure_characters.combat_level) via direct SQL so render code never names the AdventureCharacter type.
• adventure_render.go: every render fn dropped its *AdventureCharacter param. Callers pass userID id.UserID; the renderer loads AdvCharacter internally (type-inferred local) when it needs skill/streak/babysit/crafts fields. CombatLevel display reads route through dndLevelForUser. Death-status DM cost now goes through hospitalCostsForUser directly. renderAdvLeaderboard switched to a new view-model AdvLeaderboardEntry. AdvPlayerDaySummary.CombatLevel renamed to Level. Crafting-teaser logic extracted into craftingTeaserText so the existing bracket-boundary test runs without a DB.
• adventure_twinbee.go: twinBeeMaxTier and the gold-share weight loop now read D&D level via dndLevelForUser instead of c.CombatLevel.
• Call sites updated in adventure.go (8), adventure_scheduler.go (5 — including AdvPlayerDaySummary populator), adventure_arena.go (2). adventure_followups_test.go ported to call craftingTeaserText directly.
• go vet ./... && go test ./... clean. Grep-empty exit criterion below now holds for adventure_render.go and adventure_twinbee.go.

Steps (per sub-phase): column add → backfill → swap reads → swap writes → port tests → grep check.

Exit criteria L4 overall: grep -l 'AdventureCharacter\|CombatLevel' internal/plugin/adventure_{hospital,rival,masterwork,pets,housing,mortgage,render,twinbee}.go empty.

Risk: Each sub-phase is independent — can interleave with playtest. Housing has the most fields; do it last in L4 since the column count is largest.

---

7. Phase L5 — Teardown

Goal: Delete legacy types, files, and combat_engine. Branching dungeon paths become buildable.

Pre-condition: DisplayName migration (L4f-prep, ~2026-05-09 note). The plan as originally written never picked a new home for AdventureCharacter.DisplayName. It is not legacy-specific — it's the player's chosen identity, used in ~250 spots across arena, rival, scheduler, expedition, holdem, coop. L5's pre-condition grep AdventureCharacter == 0 cannot pass while DisplayName still lives on AdvCharacter.

Recommendation: add display_name TEXT NOT NULL DEFAULT '' to player_meta as a self-contained step before L4f. Backfill from adventure_character.display_name (same shape as §8). Add a loadDisplayName(userID) helper that reads from player_meta and falls back to AdvCharacter for one soak week, then flip readers. Per-call-site swap is mechanical (char.DisplayName → loadDisplayName(uid) or pass-through from caller).

Sizing: ~0.5 day for the schema/backfill/helper, then 1 day to swap the ~250 read sites in batches per file. Slot it after L2 wraps and before L4f starts.

Status (2026-05-09): schema/backfill/helper SHIPPED on adv-2.0.

• player_meta.display_name column added via column migration in internal/db/db.go.
• backfillPlayerMetaDisplayName runs on every Init: idempotent (UPDATE ... WHERE display_name = '' only touches empty rows, so dual-writes layered on top survive re-runs).
• upsertPlayerMetaDisplayName(userID, name) dual-writes from createAdvCharacter (inside the same tx, atomic with the AdvCharacter INSERT) and saveAdvCharacter (post-commit, error-logged but non-fatal).
• loadDisplayName(userID) reads player_meta → falls back to adventure_characters.display_name → empty string if neither exists.
• Tests: TestPlayerMetaDisplayNameBackfill_Idempotent, TestLoadDisplayName_FallsBackToAdvCharacter, TestCreateAdvCharacter_DualWritesDisplayName.

Reader flip SHIPPED (2026-05-09). All char.DisplayName / c.DisplayName reader sites in internal/plugin/ were swapped to loadDisplayName(userID) (or pass-through equivalents) across: combat_bridge.go, dnd_zone_cmd.go, dnd_expedition_combat.go, dnd_zone_combat.go, adventure_robbie.go, adventure_scheduler.go, adventure_hospital.go, adventure_events.go, adventure_render.go, adventure_masterwork.go, adventure.go, adventure_arena.go. The only remaining char.DisplayName references are in adventure_character.go itself (scan into struct + saveAdvCharacter SQL + dual-write to player_meta) and the player_meta.go doc comment. go vet + go test ./internal/plugin/... clean.

Pre-conditions:

• L1–L4 all shipped.
• DisplayName migrated to player_meta (see above).
• grep -rn 'AdventureCharacter' internal/plugin/ --include='*.go' | grep -v adventure_character.go | grep -v _test.go returns 0.
• grep -rn 'CombatLevel' internal/plugin/ --include='*.go' returns 0 (or only in archive/migration code).

7.1 Audit baseline (2026-05-09)

Post-L4d-reader-flip greps:

• AdventureCharacter outside adventure_character.go (excl tests): 56 hits across 15 files.
• CombatLevel (excl tests): 33 hits across 12 files.

Five of those files vanish at teardown anyway (§7 deletes): adventure_character.go, adventure_activities.go, combat_engine.go, combat_bridge.go, combat_stats.go (+ tests). Their hits don't need pre-migration.

Remaining CombatLevel callsites all use the same fallback: loadXxx(userID) returns the player_meta value when populated, otherwise calls dndLevelFromCombatLevel(adventure_characters.combat_level). To kill them we need a one-shot DnDCharacter mass-backfill so every active user has a D&D row, then drop the fallback branch.

7.2 AdvCharacter field inventory — what's still legacy-only

Already moved to player_meta (L1–L4f-prep): DisplayName, ArenaWins, ArenaLosses, InvasionScore, HospitalVisits, RivalPool, RivalUnlockedNotified, MasterworkDropsReceived, all Pet*, all House*.

Still on AdvCharacter (need migration before §7's grep-zero passes):

Bucket	Fields	Primary readers
Skills	CombatLevel, MiningSkill, ForagingSkill, FishingSkill, CombatXP, MiningXP, ForagingXP, FishingXP	dnd_sheet.go, adventure_babysit.go, hospital/rival fallback, scheduler
Streak/lifecycle	CurrentStreak, BestStreak, LastActionDate, StreakDecayed, CreatedAt, LastActiveAt	scheduler, render, babysit
Death state	Alive, DeadUntil, DeathReprieveLast, LastDeathDate, LastPardonUsed, GrudgeLocation, DeathSource, DeathLocation	combat_bridge (deletes), arena, hospital
NPC counters/debuffs	MistyLastSeen, ArinaLastSeen, MistyBuffExpires, MistyDebuffExpires, ArinaBuffExpires, NPCMsgCount, NPCMsgCountDate, MistyRollTarget, ArinaRollTarget, MistyEncounterCount, MistyDonatedCount, ThomAnimalLineFired, RobbieVisitCount	adventure_npcs.go, render
Babysit	BabysitActive, BabysitExpiresAt, BabysitSkillFocus, AutoBabysit, AutoBabysitFocus	adventure_babysit.go, scheduler
Action state	ActionTakenToday, HolidayActionTaken, CombatActionsUsed, HarvestActionsUsed	scheduler, render
Misc	Title, TreasuresLocked, CraftsSucceeded	render, treasure-drop hook

7.3 Sub-phase plan (L5a–L5h)

Each sub-phase is the same shape as L4a–L4e: column-add → backfill (idempotent, INSERT OR IGNORE / WHERE-default-only) → loadXxxState(userID) helper with AdvCharacter fallback → dual-write at every mutation site → one-week soak → reader flip → exit-grep check.

Sub-phase	Bucket	Sizing	Notes
L5a	Skills (8 fields)	1 day	SkillState struct mirroring PetState/HouseState. Mutation surface is small: checkAdvLevelUp(char, skill) + the few sites that bump *XP directly. Reader flip unblocks dnd_sheet's legacy display row and babysitDailyCost. CombatLevel rejoins this struct as a transitional column — dropped at teardown after the DnD mass-backfill. Status (2026-05-09): column + dual-write SHIPPED on adv-2.0. Eight combat_* / mining_* / foraging_* / fishing_* columns added via columnMigration. SkillState struct + HasSkills() / loadSkillState / upsertPlayerMetaSkillState / backfillPlayerMetaSkillState / skillStateFromAdvChar helpers in player_meta.go. Dual-writes wired at every mutation site: adventure_consumables.go (craft success + craft failure XP grant), adventure_events.go (event XP grant across combat/mining/foraging), adventure_arena.go::resolveArenaDeath + arenaCompleteSession (combat XP + level-up). Backfill backfillPlayerMetaSkillState() wired into Init, idempotent (only fills rows where every skill column is still zero AND the legacy row has at least one non-zero skill/XP). Tests: TestPlayerMetaSkillStateBackfill_Idempotent, TestLoadSkillState_FallsBackToAdvCharacter, TestUpsertPlayerMetaSkillState_RoundTrip in player_meta_test.go. go vet ./... && go test ./... clean. Reader flip deferred — bundled with cutting AdvCharacter writes (post-soak), per the L4e pattern.
L5b	Babysit state (5 fields)	0.5 day	Mutation surface is runBabysitDailyTrickle save in scheduler + the babysit toggle handlers. Tightly scoped. Status (2026-05-09): column + dual-write SHIPPED on adv-2.0. Five columns (babysit_active, babysit_expires_at DATETIME, babysit_skill_focus, auto_babysit, auto_babysit_focus) added via columnMigration. BabysitState + IsActive() + load/upsert/backfill/projection helpers in player_meta.go. Dual-writes wired at handleBabysitStart, handleBabysitCancel, checkBabysitExpiry. Backfill idempotent — only fills inactive rows whose legacy counterpart is active. AutoBabysit/AutoBabysitFocus + BabysitSkillFocus are dormant fields (no live mutation site) preserved for the schema migration. Tests: TestPlayerMetaBabysitStateBackfill_Idempotent, TestLoadBabysitState_FallsBackToAdvCharacter, TestUpsertPlayerMetaBabysitState_RoundTrip. go vet ./... && go test ./... clean. Reader flip deferred per L4e/L5a pattern.
L5c	NPC counters/debuffs (~13 fields)	1 day	"Later phase" referenced in L4d note. Pack the four *Expires and three *LastSeen timestamps as nullable columns; counters as ints. The roll-targets are write-once-per-encounter so dual-write is cheap. Hidden discovery mechanic — never surface in player-facing output. Status (2026-05-09): column + dual-write SHIPPED on adv-2.0. Thirteen columns added (5 nullable DATETIME for Misty/Arina last-seen + buff/debuff expiries, 1 int + 1 text for npc_msg counters, 2 ints for roll targets, 4 ints for encounter/donated/thom-fired/robbie counters). NPCState + HasNPCActivity() + load/upsert/backfill/projection helpers. Dual-writes wired at processNPCEncounters (msg-count save), npcFireEncounter (last-seen save), resolveMisty (insufficient balance, debit failure, buff/donated, declined-debuff), resolveArina (buff), adventure_robbie.go (visit count), adventure_housing.go::handleThomGreet (animal line fired). Backfill idempotent. Tests added. go vet ./... && go test ./... clean. Reader flip deferred per pattern.
L5d	Streak + action state + lifecycle (10 fields)	1 day	Action state mutates every action, so the dual-write hook is hot — ensure the upsert is in the same code path that already does saveAdvCharacter. Status (2026-05-09): column + dual-write SHIPPED on adv-2.0. Ten columns added (current_streak, best_streak, last_action_date, streak_decayed, action_taken_today, holiday_action_taken, combat_actions_used, harvest_actions_used, created_at, last_active_at). LifecycleState + HasLifecycle() + load/upsert/backfill/projection helpers. Mutation surface turned out to be tiny: only rest (adventure.go) sets ActionTakenToday — combat/harvest counts are dormant — plus the streak halve + streak update in scheduler, and the bulk daily reset. Dual-writes wired at all four sites; new resetAllPlayerMetaDailyActions parallels resetAllAdvDailyActions. createAdvCharacter now seeds created_at + last_active_at (CURRENT_TIMESTAMP) so player_meta rows are fully formed at creation. Backfill idempotent (only fills rows whose created_at is still NULL). Tests: TestPlayerMetaLifecycleStateBackfill_Idempotent, TestLoadLifecycleState_FallsBackToAdvCharacter, TestUpsertPlayerMetaLifecycleState_RoundTrip, TestResetAllPlayerMetaDailyActions. go vet ./... && go test ./... clean. Reader flip deferred per pattern.
L5e	Death state (8 fields)	1 day	Decision point: do DnDCharacter.HPCurrent == 0 semantics replace Alive/DeadUntil, or do we keep them as player_meta.alive / player_meta.dead_until? Recommendation: keep them as columns. The hospital revive path (L4a) already restores DnDCharacter.HPCurrent = HPMax alongside Alive=true, so the two are kept in sync; flipping the readers is the migration, not the death-state semantics. Status (2026-05-09): column + dual-write SHIPPED on adv-2.0. Eight columns added (alive INTEGER DEFAULT 1, dead_until/death_reprieve_last/last_pardon_used DATETIME, last_death_date/grudge_location/death_source/death_location TEXT). DeathState + load/upsert/backfill/projection helpers. Strategy switch: dual-write moved inside saveAdvCharacter itself (after the existing display_name dual-write). The mutation surface for death state spans ~50 save sites — per-site upserts would be too noisy. Every saveAdvCharacter call now propagates DeathState to player_meta. Backfill idempotent (only fills rows where every death field is still default). Tests: TestPlayerMetaDeathStateBackfill_Idempotent, TestLoadDeathState_FallsBackToAdvCharacter, TestUpsertPlayerMetaDeathState_RoundTrip, TestSaveAdvCharacter_DualWritesDeathState. go vet ./... && go test ./... clean.
L5f	Misc (Title, TreasuresLocked, CraftsSucceeded)	0.5 day	Each is a single-mutation-site field. Status (2026-05-09): column + dual-write SHIPPED on adv-2.0. Three columns (title TEXT, treasures_locked INT, crafts_succeeded INT). MiscState + load/upsert/backfill/projection helpers. Dual-write rides saveAdvCharacter alongside L5e (Title is dormant; TreasuresLocked + CraftsSucceeded mutate at known sites that already save). Backfill idempotent. Tests: TestPlayerMetaMiscStateBackfill_Idempotent, TestLoadMiscState_FallsBackToAdvCharacter, TestUpsertPlayerMetaMiscState_RoundTrip. go vet ./... && go test ./... clean.
L5g	DnDCharacter mass-backfill	0.5 day	One-shot: for every active user without a D&D row, insert a default-class character at dndLevelFromCombatLevel(adventure_characters.combat_level). Run once, idempotent (skip rows that already exist). After this lands, drop the dndLevelFromCombatLevel fallback branch in loadHospitalVisits/rivalLevelForUser/dndLevelForUser/zone gates. CombatLevel column in player_meta becomes unused at this point — drop it during the L5h cleanup. Status (2026-05-09): SHIPPED on adv-2.0. backfillDnDCharactersFromAdv in dnd_combat.go walks adventure_characters LEFT JOIN dnd_character WHERE d.user_id IS NULL, calls autoBuildCharacter (race/class inferred from archetypes; HP/AC computed; Level seeded from dndLevelFromCombatLevel(CombatLevel)), saves with AutoMigrated=1, PendingSetup=0. Idempotent — pre-existing rows (including pending-setup drafts) are skipped via the LEFT JOIN. Wired into Init after the L5f backfill. Fallbacks dropped: dndLevelForUser (dnd.go), rivalLevelForUser (adventure_rival.go), hospitalCostsForUser (adventure_hospital.go) — all now floor at level 1 when no D&D row exists. dndLevelFromCombatLevel itself is preserved (used by autoBuildCharacter for fresh-account level seeding and by dndSetupConfirm/preview/stub paths). Tests: TestL5gBackfillDnDCharacters_Idempotent, TestL5gBackfillDnDCharacters_SkipsPendingSetup in dnd_l5g_test.go. go vet ./... && go test ./... clean.
L5h	L4e in-place housing reader flip + cut all AdvCharacter dual-writes	1 day	Bundled per L4e note. Once writes stop, AdvCharacter rows go cold; dual-write removal is mechanical (delete saveAdvCharacter calls and the upserts that follow them in pairs). Status (2026-05-09): SHIPPED on adv-2.0. Strategy switch: rather than deleting 51 saveAdvCharacter call sites in pairs (which would need every site to also know about display_name/death/misc/skills/etc. internal mirrors), saveAdvCharacter itself was rewritten as a thin fan-out: LastActiveAt = now() + upsertAllPlayerMetaFromAdvChar(char). The legacy UPDATE adventure_characters is gone — the row is now read-only after createAdvCharacter seeds it. applyPlayerMetaOverlay(c) runs at the tail of loadAdvCharacter, re-sourcing every migrated subsystem (display_name, hospital, arena, masterwork, rival, skills, babysit, NPC, lifecycle, death, misc, pet, house) from player_meta so callers continue to use char.X readers transparently. The L4e housing in-place reader flip is now automatic — adventure_housing.go's char.HouseFoo reads see player_meta values via the overlay. npcMidnightReset extended to write player_meta alongside the (frozen) adventure_characters. Per-call-site upsertPlayerMetaXxx dual-writes are now redundant with saveAdvCharacter's fan-out but retained as defense — cleanup deferred. player_meta.combat_level deferred. Still actively used by babysit cost / combat_stats / activities via the overlay (those sites will be cut in final teardown alongside combat_engine.go); column drop sequenced with that. go vet ./... && go test ./... clean.

7.4 Final teardown (after L5a–L5h)

Reconciled 2026-05-09. The original deletion list was wrong. Two strategy switches during execution invalidated it:

1. L5h preserved AdventureCharacter as a load-view struct. Rather than delete 51 saveAdvCharacter call sites, L5h rewrote saveAdvCharacter as a fan-out into player_meta and added applyPlayerMetaOverlay at the tail of loadAdvCharacter. The struct is the in-memory shape every caller expects; only the backing table goes cold and eventually drops. adventure_character.go stays.
2. combat_engine.go / combat_bridge.go / combat_stats.go are not legacy. A 2026-05-09 audit confirmed SimulateCombat, CombatStats, CombatModifiers, Combatant, CombatPhase, CombatResult, CombatEvent, defaultCombatPhases, dungeonCombatPhases, DerivePlayerStats, DeriveDungeonMonsterStats, runDungeonCombat, transitionDeath, applyXPBonuses, combatDegradation, etc. are referenced across 21+ files (arena, dungeons, zones, expedition, plus every D&D combat test). The D&D system layers on top of this engine via applyDnDPlayerLayer / applyDnDEquipmentLayer / applyDnDArenaMonsterLayer / applyDnDDungeonMonsterLayer — it was never a replacement. There is nothing to migrate; these files are shared infrastructure and stay.

Revised teardown checklist:

After L5a–L5h soak (one week post-cut-of-AdvCharacter-writes per §11):

1. Three remaining CombatLevel reader fixes — SHIPPED 2026-05-09 (see L5 close-out commits 978a621 / ece838e). Babysit cost reads dndLevelForUser, dnd_sheet legacy line removed, dnd_onboarding deleted entirely.
2. Loader rewire — SHIPPED 2026-05-09. Without this step the table drop in #3 would break every login.
   • loadAdvCharacter (adventure_character.go:432) now SELECT user_id FROM player_meta + default-init struct + applyPlayerMetaOverlay. The giant 70-column SELECT against adventure_characters is gone.
   • loadAllAdvCharacters enumerates player_meta and applies the overlay per row.
   • createAdvCharacter (adventure_character.go:445) inserts player_meta only; the INSERT INTO adventure_characters line is removed.
   • npcMidnightReset and resetAllAdvDailyActions (now deleted) had their legacy UPDATEs cut; the player_meta versions are canonical.
   • stats.go::loadAdvSnapshot SELECT swapped to player_meta.
   • All achievements.go streak reads swapped to player_meta.
   • loadArenaLeaderboard LEFT JOIN swapped to player_meta.
   • Every loadXxxState helper in player_meta.go had its "fallback to adventure_characters during soak" branch deleted; player_meta is the single source of truth.
   • All backfillPlayerMeta* and backfillDnDCharactersFromAdv one-shots removed (already-completed migrations; their Init wiring is gone).
   • db.go::snapshotPreDnD gates on a sqlite_master lookup so it skips silently after the purge.
3. Purge script — SHIPPED. internal/plugin/cleanup_l5.go::purgeLegacyAdvCharacterTable runs on every Init, gated on GOGOBEE_LEGACY_PURGE=1. Idempotent (sqlite_master existence check). Drops the adventure_characters table only; the adventure_characters_pre_dnd rollback snapshot is preserved (separate GOGOBEE_PRE_DND_PURGE pass when its 30-day grace window expires). The CREATE TABLE adventure_characters clause has been removed from the schema string and the columnMigrations runner now also tolerates no such table: adventure_characters, so the table won't be re-instated on next boot.
4. player_meta.combat_level column drop — STILL DEFERRED. combat_stats.go::DerivePlayerStats (HP/Attack/Defense/Speed scaling) and combat_stats.go::applyMistyHealAmt and adventure_activities.go::adv power calculations all read char.CombatLevel via the player_meta overlay. Per §7.4's reconciliation, those files are shared infrastructure that stays — so combat_level continues to drive combat power scaling and is not safe to drop. Revisit only if/when D&D-derived stats subsume those formulas.
5. Final go vet ./... && go test ./... — clean (2026-05-09).

What stays:

• adventure_character.go — AdventureCharacter struct continues as the loaded-view shape; loadAdvCharacter SELECTs from the (now read-only) adventure_characters seed row and overlays player_meta / dnd_character state. A future cosmetic pass may rename it to drop the implication of being legacy, but that is not part of this migration. (Per feedback_avoid_dnd_naming.md, any rename must avoid "dnd"-prefixed names.)
• adventure_activities.go — already gutted in L1; the file's residual stubs can stay or be sweep-deleted in a separate cleanup, not part of teardown.
• combat_engine.go, combat_bridge.go, combat_stats.go (+ tests) — shared combat infrastructure.
• AdvLocation tier data and AdvBonusSummary plumbing — both still consumed by the live combat path; not "legacy" in the L1–L5 sense.

DB cleanup:

• adventure_character table: drop after a 30-day grace period in case of rollback. dnd_l5_cleanup.go migration script gated on GOGOBEE_LEGACY_PURGE=1. Default off; manual flip after confirming.
• Equipment table stays — it was always per-user, never per-AdvCharacter.
• player_meta.combat_level column drop sequenced with the three reader fixes above.

Branching dungeon paths: unblocked. The dnd_zone_run schema is the only one we still own; rebuild/expand it without AdvCharacter pressure. Out of scope for this doc — see project_branching_paths_post_legacy.md memory note.

---

8. Cross-cutting — DB backfills

Every phase that moves a field from adventure_character to player_meta runs the same shape of backfill:

// In Init() or a one-shot migration runner
func backfillPlayerMeta(db *sql.DB) error {
    rows, _ := db.Query(`SELECT user_id, arena_wins, arena_losses, ... FROM adventure_character`)
    for rows.Next() {
        // INSERT OR IGNORE into player_meta
    }
}

Idempotency rules (per Phase R1's archiveOrphanZoneRuns precedent):

• All backfills use INSERT OR IGNORE.
• All backfills are safe to re-run.
• Each backfill logs the row count it touched.

Order of backfills:

1. L1 — babysit_*, auto_babysit* columns.
2. L2 — arena_wins, arena_losses, invasion_score.
3. L3 — none (co-op didn't store on AdvCharacter).
4. L4a — hospital_visits, last_death_date, death_source, death_location, last_pardon_used, death_reprieve_last.
5. L4b — rival_pool, rival_unlocked_notified.
6. L4c — masterwork_drops_received, treasures_locked.
7. L4d — pet fields.
8. L4e — house fields.
9. L4f — streak/title/grudge fields, NPC msg counters, NPC seen/buff timestamps.
10. L5 — drop adventure_character table.

---

9. Testing strategy

• Each phase ships with new tests for the migrated subsystem and a *_migration_test.go covering backfill idempotency (matching R1's pattern).
• Existing tests are ported, not deleted — same test names, fixtures swap from AdvCharacter to DnDCharacter.
• A new legacy_residue_test.go runs at the package level and greps the source tree for forbidden symbols once each phase lands; this guards against regressions.

// legacy_residue_test.go skeleton
func TestNoCombatLevelReferencesAfterL5(t *testing.T) {
    if !legacyMigrationDone { t.Skip() }
    // walk filepath, fail on grep "CombatLevel"
}

---

10. Sequence & rough sizing

Phase	Est. session count	Blocking on
L1 — Babysit/scheduler	1	—
L2 — Arena (boss flow rebuild)	2–3	feature flag in place; renderBossOutcome extraction lands first
L3 — Co-op dungeons (DELETE)	0.5	— (independent of L2)
L4a — Hospital	0.5	—
L4b — Rival	1	—
L4c — Masterwork	0.5	DnDCharacter skill fields exist (§2.2)
L4d — Pets	1	player_meta schema
L4e — Housing/mortgage	1	—
L4f — TwinBee/render	0.5	L1–L4 done
L5 — Teardown	1	all above + 30-day grace

Total: ~10 sessions over ~3–6 weeks of real time, including playtest soak between phases. Don't compress this into a single sprint — each phase needs production exposure before the next one builds on it.

---

11. Rollback strategy

Each phase is reversible until L5:

• L1–L4 do not delete columns or tables. They add player_meta columns and dual-read briefly during the swap.
• If a phase regresses, revert the read-site swap; backfill data still flows back to adventure_character because L1–L4 do not stop writing to AdvCharacter until §6 dual-write is dropped per phase.

Dual-write rule: for the duration of L1–L4, every write to a migrated field goes to both AdvCharacter and player_meta. Reads come from player_meta. This is removed phase-by-phase only after one full real week with no rollback triggered.

L5 is the irreversible step. Gate on GOGOBEE_LEGACY_PURGE=1.

---

12. Decisions locked (2026-05-08)

All four pre-implementation questions answered:

1. CombatLevel→Level: direct copy. CombatLevel doesn't have semantic meaning — it's just "starting Level." No formula, no cap-compression.
2. AdvEquipment: kept as-is. No rename. Type stays AdvEquipment, table stays adventure_equipment. (Naming guidance: avoid new dnd_* symbols throughout this migration — see §2.1 callout.)
3. CombatXP→XP: discarded. Players start fresh; new XP accumulates from 0 at the floor of their migrated Level.
4. Co-op dungeons: dropped entirely (see §5). Not migrated. Different design coming later.

No outstanding pre-implementation questions. Tuning questions during each phase (HP/AC tables, threshold brackets) get decided in the moment.

---

End of Legacy Migration document. Pair with companion docs in Claude Code sessions when working any L-phase.