feedback7 G-SMALL: co-op rooms can make AI teammates draft last (PR #368 by @anAtheist987)

Applied the host-only room option 「AI 队友最后选择」, default off. Off, the draft order and the random streams stay as they are. On, humans draft before AI seats after the existing shuffle, and a skip stays ahead of the AI seats.

Dropped docs/history/0.2.2.md and every §27 citation. The player-facing sentence is in docs/PLAYING.md. The room-option rule is in docs/design/match.md, docs/design/client.md and docs/design/network.md. The #338 per-bot faction and ban presets are not included.

Tests: node --test test/lobby-ai-last.test.js test/match/ai-picks-last.test.js test/ui/ai-picks-last.test.js — 18 pass. node --test test/lobby.test.js test/client-static.test.js — 378 pass. node tools/i18n.mjs check --all --strict — 1032/1032 in en, ja, ko and zh-TW, 0 errors.

docs/PLAYING.md

@@ -17,8 +17,8 @@
 | 阶段 | 说明 |
 |---|---|
 | 确认本局信息 | 本局地图（标准模拟固定为「战场#01」；险境从 8 张地图中随机，绝境 / 终极从不含战场#01 的 7 张中随机）、敌方派系（三种特训敌人类型，如折射、飞行：和官方一样，每种占全局 15 个回合位中的 3 个，第 14 回合领袖战和第 15 回合隐秘核心也各占一个位，所以险境 / 绝境 / 终极第 1–13 回合中有 7–9 波是这三种类型、每种最多 3 波，其余各波是「特异」类型；每波只有一种类型）、**被禁用的盟约及其干员**、领袖预告。所有人确认后继续；同盟模拟最多 25 秒；只有你一名玩家时（独立模拟，或同盟模拟只带 AI 队友）不限时。 |
-| 选择策略 | 40 名策略（分队长）决定**初始目标生命值（20–45）**和一条永久规则。同盟：随机顺序轮流选，**每人 30 秒**，右上角和「决策中」显示同一个倒计时；AI 队友立即选完；队友已选的不能重复，每人可**跳过一次**（排到最后）；超时自动选你**当前选中**的策略（已被队友选走则选华法琳）。独立：自由选择、不限时；同盟模拟只有你一名玩家时也不限时。选的时候可以点左侧决策顺序下方的「查看禁用盟约与干员」，再看一遍「确认本局信息」里的盟约（置灰、禁用人数）和本局禁用干员：只能查看，倒计时照常走，底部也显示轮到谁和剩余秒数；点「关闭」、点窗口外面或按 Esc 关闭，轮到下一位时会自动关闭。 |
-| 机变 | 部分回合开始前出现：同盟共 6 张卡轮流各取 1 张（首位 30 秒，其余 16 秒；只有你一名玩家时不限时），独立 3 选 1。卡片包括装备、资金、干员、盟约层数、悬赏等；**悬赏决策**为你的作战添加悬赏敌人，卡上用蓝字标出持续多久：「下场作战」/「接下来两场作战」的只出现一场或两场，之后不再出现；官方的「多轮悬赏」（原文写「之后的每场作战」）在这里也按「接下来两场作战」处理，只出现两场（如教鞭的法术大师A2·多轮战术特训）。各回合的悬赏决策按官方对局截图来出：第 3 回合是 6 张「接下来两场作战」的悬赏（3 张 1 资金、2 张 2 资金、1 张 3 资金）；第 9 回合是各首领的「下场作战」悬赏和「源石虫·特训」；绝境 / 终极的第 11 回合多半是悬赏决策（也可能是机密商店或战术决策），其中的悬赏通常有 1 只特异巨兽，其余是各阵营的「下场战斗」悬赏。击倒悬赏敌人的人（联防中的队友也算）获得资金；右侧效果栏会写「还剩 N 场作战」。**机密商店**的 6 件装备都免费，和官方一样可能出现两件相同的装备（各算一张卡，可以分别被选走）；第 11 回合（绝境 / 终极）的机密商店按官方：2 件 VI 阶、至少 1 件 V 阶和 1 枚盟约之币，标准 / 险境较早回合的机密商店各阶装备都可能出现。**战术决策**也和官方一样可能出现两张相同的卡（官方截图里出现过两张「补给」；各算一张卡，可以分别被选走，每张只生效一次，两人各选一张全队卡则效果叠加）；第 11 回合（绝境 / 终极）的战术决策按官方截图只出盟誓、驰援、列装 / 财富 / 补给 / 整备 / 升华等增益卡，不出削弱敌人的卡和战场演变卡。每张卡左上是图标和名称，下面写着完整效果（与详情卡相同的官方描述，手机上也显示）；已被选走的卡变暗，右上角显示选走它的玩家头像（悬停可看名字）。选卡要**点两次**：第一次只选中（金框 +「确认选择 · 再次点击」），再点同一张或点右上的「确认选择」才生效；点别的卡换选，按 Esc 或点空白处取消。 |
+| 选择策略 | 40 名策略（分队长）决定**初始目标生命值（20–45）**和一条永久规则。同盟：随机顺序轮流选，**每人 30 秒**，右上角和「决策中」显示同一个倒计时；AI 队友立即选完；队友已选的不能重复，每人可**跳过一次**（排到最后）；创建者可以在同盟等待室打开「**AI 队友最后选择**」（默认关闭）：选择策略和机变轮选时所有博士都排在 AI 队友前面（博士之间、AI 之间仍是随机顺序，AI 托管或掉线的博士也算博士），跳过时排到其他还没选的博士之后、AI 之前（没有其他博士时排到最后）；超时自动选你**当前选中**的策略（已被队友选走则选华法琳）。独立：自由选择、不限时；同盟模拟只有你一名玩家时也不限时。选的时候可以点左侧决策顺序下方的「查看禁用盟约与干员」，再看一遍「确认本局信息」里的盟约（置灰、禁用人数）和本局禁用干员：只能查看，倒计时照常走，底部也显示轮到谁和剩余秒数；点「关闭」、点窗口外面或按 Esc 关闭，轮到下一位时会自动关闭。 |
+| 机变 | 部分回合开始前出现：同盟共 6 张卡轮流各取 1 张（随机顺序，开启「AI 队友最后选择」时博士先选；首位 30 秒，其余 16 秒；只有你一名玩家时不限时），独立 3 选 1。卡片包括装备、资金、干员、盟约层数、悬赏等；**悬赏决策**为你的作战添加悬赏敌人，卡上用蓝字标出持续多久：「下场作战」/「接下来两场作战」的只出现一场或两场，之后不再出现；官方的「多轮悬赏」（原文写「之后的每场作战」）在这里也按「接下来两场作战」处理，只出现两场（如教鞭的法术大师A2·多轮战术特训）。各回合的悬赏决策按官方对局截图来出：第 3 回合是 6 张「接下来两场作战」的悬赏（3 张 1 资金、2 张 2 资金、1 张 3 资金）；第 9 回合是各首领的「下场作战」悬赏和「源石虫·特训」；绝境 / 终极的第 11 回合多半是悬赏决策（也可能是机密商店或战术决策），其中的悬赏通常有 1 只特异巨兽，其余是各阵营的「下场战斗」悬赏。击倒悬赏敌人的人（联防中的队友也算）获得资金；右侧效果栏会写「还剩 N 场作战」。**机密商店**的 6 件装备都免费，和官方一样可能出现两件相同的装备（各算一张卡，可以分别被选走）；第 11 回合（绝境 / 终极）的机密商店按官方：2 件 VI 阶、至少 1 件 V 阶和 1 枚盟约之币，标准 / 险境较早回合的机密商店各阶装备都可能出现。**战术决策**也和官方一样可能出现两张相同的卡（官方截图里出现过两张「补给」；各算一张卡，可以分别被选走，每张只生效一次，两人各选一张全队卡则效果叠加）；第 11 回合（绝境 / 终极）的战术决策按官方截图只出盟誓、驰援、列装 / 财富 / 补给 / 整备 / 升华等增益卡，不出削弱敌人的卡和战场演变卡。每张卡左上是图标和名称，下面写着完整效果（与详情卡相同的官方描述，手机上也显示）；已被选走的卡变暗，右上角显示选走它的玩家头像（悬停可看名字）。选卡要**点两次**：第一次只选中（金框 +「确认选择 · 再次点击」），再点同一张或点右上的「确认选择」才生效；点别的卡换选，按 Esc 或点空白处取消。 |
 | 休整期 | 购买、摆阵、配装备、冻结 / 刷新、升级调度中心；同盟有倒计时（65–215 秒，随回合增加）；独立模拟、以及只有你一名玩家（只带 AI 队友）的同盟模拟不限时。所有人「准备就绪」即提前开战，全员就绪前可取消。 |
 - **特殊地形点一下就有说明**：战场上的**活性源石**、**沼泽**、**排气格栅**、**深水区**，以及**红门 / 蓝门 / 传送点**，点一下就会弹出它自己的说明卡——名称、机制，以及**这一关自己的数值**（比如战场#04 的活性源石：每秒 70 点真实伤害、攻击力 +20%、攻击速度 +20、持续 300 秒）。休整期和作战期都能点。普通地板 / 道路 / 高台点了不会弹东西，所以点一下仍然只是「取消选中、关掉卡片」。
 | 作战 | 每人在自己的战场各自作战（战斗在你的浏览器里模拟，2 倍速）。干员按**逐列从左到右、每列从上到下**的顺序（官方「从上到下>从左到右」：最左一列最先）自动部署并消耗部署费用（初始 10，+1/秒）。时限 45–115 秒（实际秒数，即屏幕上的倒计时），时间到仍存活的敌人算漏怪。有敌人进入蓝门时，顶栏的目标生命值会**立即**显示扣除后的数值（红字 + 「−N」，每回合至多 10 点），结算时确定；联防阶段标注「联防中」，队友拦下的部分最后不扣。左侧队伍栏同样显示队友的待扣生命值。被击倒的干员**留在倒下的格子上**（倒地姿势、略微变灰），之后也在这一格再部署（与官方一样；倒在其他干员或召唤物初始位置上的，会回到自己的初始位置躺下，召唤物已经消失也一样；唯一的例外是乌尔比安：三技能把他移到船锚处期间被击倒时，他回到自己的部署位躺下、再部署——这是项目维护者 2026-10-07 应社区反馈有意做出的改动，与官方「原地倒下」不同）；因自身效果强制退场的干员（史尔特尔「余烬」结束、耀骑士临光 2 技能结束等）同样倒在原地、在原地再部署；倒地干员所在的格子**不会被占用**，突袭盟约的再部署、援军、召唤物都会避开它。头上的圆圈是再部署倒计时：绿色圆环 + 秒数；变成黄色「DP」表示部署费用不够。血条下方的一行是**元素损伤**（与原版一致：元素图标 + 白条）：干员为带图标的彩色圆盘，敌人为小号纯色圆盘，右侧白条是剩余元素值，像血条一样从右往左减少，白条耗尽的那一下就是爆条（被大额元素损伤一次打掉一截时白条也会一次少一截，例如掠海漂移体每击约为 25%–50%）；爆条后进入爆发冷却（灼燃 / 神经 / 侵蚀 10 秒，敌方侵蚀 8 秒，凋亡 15 秒），这时白条变成**元素颜色**（神经青绿、侵蚀蓝、灼燃橙红、凋亡灰紫）并在冷却期间慢慢回满、图标闪烁——彩色条表示已经爆条、正在承受爆发效果，不是还剩的元素值；期间所有元素都不会累积也无法被治疗，结束后清零。元素爆发造成的是**无来源伤害**，不吃干员的增伤、穿透和装备加成（例如深巡打海嗣时灼燃爆发固定 7000），击杀仍记在爆条的干员名下；元素脆弱只提高元素伤害，不加快元素条；脆弱不影响元素伤害。已被击杀的敌人不会再被附加元素损伤。 |

docs/design/client.md

@@ -37,7 +37,7 @@ Visuals: oblique perspective board (tilted ~30°, trapezoid tiles), raised highl
 
 Look & feel: research 06 §11–§12 (near-black green-grey panels, mint `#4ed8af` accents, gold prices, bracket frames, hexagon badges, bond discs, 7-segment countdown). Fonts: Noto Sans SC (Google Fonts with local fallback), Bender/Novecento self-hosted for numerals and Latin micro-labels.
 
-Screens: **Title** (season art backdrop, 开始 → nickname), **Lobby** (独立模拟 / 同盟模拟 → create or join; recent rooms), **Room** (4 seats, invite code + copy link, difficulty picker (host), add/remove AI, ready, start), **Briefing** (INFO_CHECK: stage, factions, disabled bonds, banned chess, boss silhouette, ready x/4), **Band draft** (grid of 40 bands with icon/name/LP/effect; turn order list; skip; 查看禁用盟约与干员 under the order list opens the briefing's bond rows, legend and banned operators again in a read-only dialog — one component, `ui/matchInfo.js`, §21.28), **Game** (Pixi field + DOM HUD: top bar with round/phase capsule/LP (live during the own battle, §17.5)/timer/ready; bond strip + popups; left team panel with LP/status/emote bubbles, click to watch (a boss round frames the viewer's pair in green, §15); bottom shop bar (level card, 3–5 chess cards, item card, funds, refresh, freeze, collapse); detail panel on click/hover (header with bonds, then 特质 — the operator's own effect — right under it, 特性, stats (live: the battle's own numbers / the start-of-battle ones in prep, §18.5), skill, module, equipped items, talents: §17.5); enemy preview drawer (next round enemies with counts, factions; its 本局信息 tab lists the briefing's disabled bonds and banned operators, §21.28); 机变 overlay (the official card: framed icon + name, the effect text — data `descRaw` — under it, the taker's round avatar at the top-right; two taps, §18.2, §20.7); merge reward overlay (the promotion reward, or a special offer — 凯瑟琳's 定向投放 … — as item / chess cards under its source's label, with the count of offers queued behind it, §21.2); phase banners; the round's result box at SETTLE (the official 「作战结束」 + 「全员无伤！」 / 「生命值减少 −N」 for the viewer's own LP — after a 联防 the server's charge, `m.public.uniteResult.losses` — with the matching BATTLEOVER sound; none in the boss rounds or for a viewer not in the round; GitHub #235, PR #112); ticker (by broadcast priority, highest first; a leader-damage line plays only in its round and a player's newer one replaces the older, §21.10); toasts; emote wheel; settings (volume, quality, show damage numbers)), **Result** (victory/defeat, rounds, per-player lineup, stats, titles, back to room).
+Screens: **Title** (season art backdrop, 开始 → nickname), **Lobby** (独立模拟 / 同盟模拟 → create or join; recent rooms), **Room** (4 seats, invite code + copy link, difficulty picker (host), the co-op 「AI 队友最后选择」 switch (host, off by default; read-only for the others), add/remove AI, ready, start), **Briefing** (INFO_CHECK: stage, factions, disabled bonds, banned chess, boss silhouette, ready x/4), **Band draft** (grid of 40 bands with icon/name/LP/effect; turn order list; skip; 查看禁用盟约与干员 under the order list opens the briefing's bond rows, legend and banned operators again in a read-only dialog — one component, `ui/matchInfo.js`, §21.28), **Game** (Pixi field + DOM HUD: top bar with round/phase capsule/LP (live during the own battle, §17.5)/timer/ready; bond strip + popups; left team panel with LP/status/emote bubbles, click to watch (a boss round frames the viewer's pair in green, §15); bottom shop bar (level card, 3–5 chess cards, item card, funds, refresh, freeze, collapse); detail panel on click/hover (header with bonds, then 特质 — the operator's own effect — right under it, 特性, stats (live: the battle's own numbers / the start-of-battle ones in prep, §18.5), skill, module, equipped items, talents: §17.5); enemy preview drawer (next round enemies with counts, factions; its 本局信息 tab lists the briefing's disabled bonds and banned operators, §21.28); 机变 overlay (the official card: framed icon + name, the effect text — data `descRaw` — under it, the taker's round avatar at the top-right; two taps, §18.2, §20.7); merge reward overlay (the promotion reward, or a special offer — 凯瑟琳's 定向投放 … — as item / chess cards under its source's label, with the count of offers queued behind it, §21.2); phase banners; the round's result box at SETTLE (the official 「作战结束」 + 「全员无伤！」 / 「生命值减少 −N」 for the viewer's own LP — after a 联防 the server's charge, `m.public.uniteResult.losses` — with the matching BATTLEOVER sound; none in the boss rounds or for a viewer not in the round; GitHub #235, PR #112); ticker (by broadcast priority, highest first; a leader-damage line plays only in its round and a player's newer one replaces the older, §21.10); toasts; emote wheel; settings (volume, quality, show damage numbers)), **Result** (victory/defeat, rounds, per-player lineup, stats, titles, back to room).
 
 盟约栏支持「收起／展开盟约」（GitHub #142）：收起时隐藏完整列表并关闭由列表打开的浮层，让原图标区域的指针事件到达棋盘，只保留至少 44×44 CSS px 的恢复按钮。折叠状态在本局阶段变化、观看队友时保留；展开后仍按当前观看对象显示最新盟约。按钮支持 Enter / Space，聚焦按钮时 Space 不触发准备或暂停。
 

docs/design/match.md

@@ -7,11 +7,11 @@ Part of [DESIGN.md](../DESIGN.md) (the index; section numbers are global).
 ### 6.1 State machine (Match.js)
 
 ```
-LOBBY(room) → INFO_CHECK (co-op 25 s; solo and any single-human match untimed (§18.2); all ready ⇒ skip; the operator loadout (§16) locks when it ends) → BAND_DRAFT (co-op: random order, ONE countdown — `BAND_TURN_SECONDS` 30 s per turn = m.public.deadline, AI seats pick at once, 1 skip each, a strategy a teammate already took is refused (队友已选), timeout ⇒ the strategy the player highlights (`g.bandFocus`) while free, else band_bldsk, else the first free one; solo: free pick, no timer, no skip; a single human: untimed) → BATTLE_CHECK (3 s)
+LOBBY(room) → INFO_CHECK (co-op 25 s; solo and any single-human match untimed (§18.2); all ready ⇒ skip; the operator loadout (§16) locks when it ends) → BAND_DRAFT (co-op: random order — the room option 「AI 队友最后选择」 (host, off by default; `room.setAiPicksLast`) puts every human seat before every AI seat, each group keeping the drawn order, and draws no extra random number; a skipping human goes behind the other humans still to pick and ahead of the AI seats, or to the very end when no other human remains [ASSUMED] —, ONE countdown — `BAND_TURN_SECONDS` 30 s per turn = m.public.deadline, AI seats pick at once, 1 skip each, a strategy a teammate already took is refused (队友已选), timeout ⇒ the strategy the player highlights (`g.bandFocus`) while free, else band_bldsk, else the first free one; solo: free pick, no timer, no skip; a single human: untimed) → BATTLE_CHECK (3 s)
 → loop r = 1..lastRound:
      ROUND_START   (income, upgrade price −1 (floor 0), temp NOT wiped — what overflowed after the last prep's deadline is shown in this
                     prep (§6.2 temp overflow), unfrozen shop slots rerolled, frozen kept, <进入休整期时> effects)
-     [SP_DRAFT]    (if r ∈ spRounds: 机变 draft; co-op 30 s first picker / 16 s others; solo 3 cards; solo / single human untimed;
+     [SP_DRAFT]    (if r ∈ spRounds: 机变 draft; co-op: random order (「AI 队友最后选择」, off by default: humans first, the same partition as the strategy draft), 30 s first picker / 16 s others; solo 3 cards; solo / single human untimed;
                     a card is picked with two taps, §18.2)
      PREP          (co-op: timer from config, ends when all alive humans+bots ready; solo / single human: untimed, ends on ready)
      PREP_END      (<休整期结束时> effects; unfrozen shop cleared; temp overflow: Ready is blocked while temp is non-empty; at the deadline

docs/design/network.md

@@ -7,8 +7,8 @@ Part of [DESIGN.md](../DESIGN.md) (the index; section numbers are global).
 Transport: one WebSocket per tab at `/ws`, JSON text frames `{ t: '<type>', ...payload }`. Client requests may carry `rid` (request id); the server's direct reply echoes `rid` (`ok` or `error`). Server pushes have no `rid`. Max frame 64 KB inbound; rate limit 40 msgs/s per connection (excess dropped with `error RATE`).
 
 ### 8.1 Session & lobby
-C→S: `hello {name, token?, version}` · `room.create {mode:'solo'|'coop', difficulty}` · `room.join {code}` · `room.leave` · `room.ready {ready}` · `room.setDifficulty {difficulty}` (host) · `room.addBot` / `room.removeBot {seat}` (host) · `room.kick {seat, playerId}` (host, before the match: another human leaves the room and gets `room.closed {reason:'kicked'}`; may join again; `playerId` = the player the host confirmed, a seat that changed hands meanwhile → `BAD_TARGET`) · `room.start` (host) · `room.loadout {entries}` (§16: any time in the lobby / room and during INFO_CHECK, then `WRONG_PHASE`; heavy rate-limit bucket; the match exposes it as `m.private.loadout`) · `room.ownership {notOwned}` (0.2.0 补位, the 干员持有 tab: the base chess ids marked as not owned — ≤ 160 ids, kept leniently: anything but a droppable NORMAL chess is dropped; stored on the session and the seat, a match takes the seat's list when it starts and never changes it — during a match `ROOM_STARTED` 'stored for the next match'; heavy bucket; the match exposes it as `m.private.standIns`) · `room.diy {picks}` (0.2.0 自选编队: `{ [slotBaseId]: { charId, skillIndex?, uniEquipId? } | null }` for the four DIY slots — ≤ 8 entries, kept leniently: shared/protocol.js `checkDiyPicks` drops an illegal pick (an operator without a kit, another tier's prototype, a prototype off its locked skill, a module of another game mode (集成战略 / 生息演算), an owned operator's second slot, the same operator twice in a tier, an unknown slot), only malformed picks are `BAD_MSG`; stored on the session and the seat like the not-owned list, a match takes the seat's picks when it starts — during a match `ROOM_STARTED` 'stored for the next match'; heavy bucket; the match exposes them as `m.private.diy`) · `ping {c}`
-S→C: `welcome {playerId, token, name, serverNow}` · `room.state {code, hostId, mode, difficulty, seats:[{seat, playerId, name, isBot, ready, connected}|null ×4]}` · `room.closed {reason}` · `pong {c, s}` · `error {rid?, code, msg}` · `ok {rid}`
+C→S: `hello {name, token?, version}` · `room.create {mode:'solo'|'coop', difficulty}` · `room.join {code}` · `room.leave` · `room.ready {ready}` · `room.setDifficulty {difficulty}` (host) · `room.setAiPicksLast {on}` (host, co-op, before the match — `ROOM_STARTED` during it, `BAD_TARGET` in a solo room; un-readies the other humans like a difficulty change; the match takes it as `opts.aiPicksLast`: humans draft before AI seats, off by default, no extra random draw) · `room.addBot` / `room.removeBot {seat}` (host) · `room.kick {seat, playerId}` (host, before the match: another human leaves the room and gets `room.closed {reason:'kicked'}`; may join again; `playerId` = the player the host confirmed, a seat that changed hands meanwhile → `BAD_TARGET`) · `room.start` (host) · `room.loadout {entries}` (§16: any time in the lobby / room and during INFO_CHECK, then `WRONG_PHASE`; heavy rate-limit bucket; the match exposes it as `m.private.loadout`) · `room.ownership {notOwned}` (0.2.0 补位, the 干员持有 tab: the base chess ids marked as not owned — ≤ 160 ids, kept leniently: anything but a droppable NORMAL chess is dropped; stored on the session and the seat, a match takes the seat's list when it starts and never changes it — during a match `ROOM_STARTED` 'stored for the next match'; heavy bucket; the match exposes it as `m.private.standIns`) · `room.diy {picks}` (0.2.0 自选编队: `{ [slotBaseId]: { charId, skillIndex?, uniEquipId? } | null }` for the four DIY slots — ≤ 8 entries, kept leniently: shared/protocol.js `checkDiyPicks` drops an illegal pick (an operator without a kit, another tier's prototype, a prototype off its locked skill, a module of another game mode (集成战略 / 生息演算), an owned operator's second slot, the same operator twice in a tier, an unknown slot), only malformed picks are `BAD_MSG`; stored on the session and the seat like the not-owned list, a match takes the seat's picks when it starts — during a match `ROOM_STARTED` 'stored for the next match'; heavy bucket; the match exposes them as `m.private.diy`) · `ping {c}`
+S→C: `welcome {playerId, token, name, serverNow}` · `room.state {code, hostId, mode, difficulty, aiPicksLast, seats:[{seat, playerId, name, isBot, ready, connected}|null ×4]}` · `room.closed {reason}` · `pong {c, s}` · `error {rid?, code, msg}` · `ok {rid}`
 
 Platform additions (implemented): `welcome.{resumed, version}`, `welcome.diyKitted` (0.2.0: the operators a 自选 slot may field — server/sim/content/kits/index.js `KITTED_CHARS`, the picker's list), `room.state.inMatch`, `error.detail`; `room.closed.reason ∈ 'timeout'|'kicked'|'empty'|'shutdown'` (`kicked`: room.kick / room.removeSpectator; `empty`: a spectator whose room lost its last player); WebSocket close codes 4001 (session taken over by another socket — client must not auto-reconnect), 4002 (no hello in time), 1008 (flooding), 1001 (shutdown). The host's `room.start` counts as the host being ready. After any (re)`hello` the server pushes `room.state` and, if a match runs, the match resends `m.public`/`m.private` (+`m.field`, or the field's `b.start` under client-side combat). **Reconnect window:** a dropped session stays resumable for 10 min (`net.js NET_DEFAULTS.reconnectWindowMs`; co-op seats keep playing their last lineup meanwhile, §6.6); a session that drops while its **solo** room's match runs stays resumable for the official `config.constants.singleReconnectTime` (86 400 s = 24 h; lobby option `soloReconnectWindowMs`; research 01 §1 "24小时内随时返回") — the untimed solo run simply waits. Only when the window expires does the drop become `match.onLeave` (co-op: 中途退出 = elimination; solo: the run ends `'abandoned'`). The client keeps its token in sessionStorage plus a recent-token list in localStorage, so reopening the tab resumes. Everything lives in server memory: a server restart ends every room and run. The lobby⇄match interface (constructor opts, `start/handle/onDisconnect/onReconnect/onLeave/dispose`) is documented verbatim at the top of `server/match/Match.js` and is normative. `server/data.js` provides `getData()` + index getters (`getChess`, `getBond`, `getGarrison`, `getItem`, `getBand`, `getEffect`, `getEnemy`, `getWave`, `getStage`, `getBoss`, `getToken`, `getConfig`, `getMode`). Note: the skill trigger rule lives at `chess.skill.trigger.rule` in data.
 

public/css/screens/room.css

@@ -296,6 +296,13 @@
 }
 .dpick__opt.is-active .icon { opacity: 1; filter: drop-shadow(0 0 5px var(--d-color)); }
 .dpick--ro { border: 0; background: none; gap: .18rem; align-items: center; font-size: .14rem; }
+/* 「AI 队友最后选择」 (GitHub #338, co-op): one switch styled like a difficulty option, under the difficulty picker */
+.room-bar__opts { display: flex; flex-direction: column; align-items: flex-start; gap: .08rem; min-width: 0; }
+.ailast { display: flex; align-items: center; gap: .12rem; font-size: .14rem; }
+.ailast__opt { --d-color: var(--mint-400); height: .36rem; padding: 0 .14rem; border: 1px solid var(--line-2); background: rgba(0, 0, 0, .3); font-size: .15rem; letter-spacing: .04em; }
+.ailast__opt:last-child { border-right: 1px solid var(--line-2); }
+.ailast__opt .icon { opacity: .25; }
+.ailast__opt .icon.is-on { opacity: 1; }
 
 .ready-count[hidden] { display: none; }
 .ready-count { display: flex; align-items: baseline; gap: .06rem; font-size: .16rem; }

public/i18n/en.json

@@ -104,6 +104,9 @@
   "复制密钥": "Copy Key",
   "复制链接": "Copy Link",
   "由创建者选择": "Chosen by the Host",
+  "由创建者设置": "Set by the Host",
+  "AI 队友最后选择": "AI Teammates Pick Last",
+  "策略与机变轮选时，所有博士先于 AI 队友选择": "In the Strategy and Improv drafts, every Doctor picks before the AI teammates",
   "连接中断，请稍候重试": "Connection lost, please try again shortly",
   "离开同盟": "Leave Alliance",
   "你是同盟的创建者，离开后创建者身份将移交或同盟解散。确定离开吗？": "You are the Host of this Alliance. If you leave, host duties will be handed over or the Alliance will disband. Leave anyway?",

public/i18n/ja.json

@@ -110,6 +110,9 @@
   "复制密钥": "コードをコピー",
   "复制链接": "リンクをコピー",
   "由创建者选择": "ホストが選択",
+  "由创建者设置": "ホストが設定",
+  "AI 队友最后选择": "AI チームメイトは最後に選択",
+  "策略与机变轮选时，所有博士先于 AI 队友选择": "戦術と調整の順番選択では、すべてのドクターが AI チームメイトより先に選びます",
   "连接中断，请稍候重试": "接続が切断されました。しばらくしてから再試行してください",
   "离开同盟": "同盟から退出",
   "你是同盟的创建者，离开后创建者身份将移交或同盟解散。确定离开吗？": "あなたはこの同盟のホストです。退出するとホストが他のドクターに移るか、同盟が解散します。退出しますか？",

public/i18n/ko.json

@@ -106,6 +106,9 @@
   "复制密钥": "코드 복사",
   "复制链接": "링크 복사",
   "由创建者选择": "방장이 선택",
+  "由创建者设置": "방장이 설정",
+  "AI 队友最后选择": "AI 팀원은 마지막에 선택",
+  "策略与机变轮选时，所有博士先于 AI 队友选择": "전략과 기회 순서 선택에서 모든 박사가 AI 팀원보다 먼저 선택합니다",
   "连接中断，请稍候重试": "연결이 끊어졌습니다. 잠시 후 다시 시도해 주세요.",
   "离开同盟": "동맹 나가기",
   "你是同盟的创建者，离开后创建者身份将移交或同盟解散。确定离开吗？": "이 동맹의 방장입니다. 나가면 방장 권한이 이양되거나 동맹이 해산됩니다. 정말 나가시겠습니까?",

public/i18n/zh-TW.json

@@ -108,6 +108,9 @@
   "复制密钥": "複製金鑰",
   "复制链接": "複製連結",
   "由创建者选择": "由建立者選擇",
+  "由创建者设置": "由建立者設定",
+  "AI 队友最后选择": "AI 隊友最後選擇",
+  "策略与机变轮选时，所有博士先于 AI 队友选择": "策略與機變輪選時，所有博士先於 AI 隊友選擇",
   "连接中断，请稍候重试": "連線中斷，請稍候重試",
   "离开同盟": "離開同盟",
   "你是同盟的创建者，离开后创建者身份将移交或同盟解散。确定离开吗？": "你是同盟的建立者，離開後建立者身分將移交或同盟解散。確定離開嗎？",

public/js/screens/room.js

@@ -1,6 +1,6 @@
 // Room screen (同盟等待室): 4 seat cards (avatar frame, name, ready state, AI badge, host crown),
-// host controls (difficulty picker, add/remove AI in co-op, start), invite code with copy code /
-// copy link, ready toggle and leave.
+// host controls (difficulty picker, add/remove AI and the 「AI 队友最后选择」 switch in co-op, start), invite code with
+// copy code / copy link, ready toggle and leave.
 //
 // Start rule (server/lobby.js): room.start needs every *other* human connected and ready; the
 // host's start counts as the host's ready. So 开始模拟 is enabled exactly then and sends room.start
@@ -69,6 +69,19 @@ export function roomFacts(room, myId) {
   };
 }
 
+/**
+ * The co-op room option 「AI 队友最后选择」 (GitHub #338; room.setAiPicksLast, room.state.aiPicksLast): in the strategy and
+ * 机变 drafts every human picks before the AI teammates. null in a solo room (no AI teammates); otherwise its state (off
+ * when the server sends none) and whether this player may switch it — the host only, the others see it read-only.
+ * @param {any} room room.state payload
+ * @param {any} myId
+ * @returns {{ on: boolean, editable: boolean } | null}
+ */
+export function aiLastOption(room, myId) {
+  if (!room || room.mode === 'solo') return null;
+  return { on: room.aiPicksLast === true, editable: room.hostId != null && room.hostId === myId };
+}
+
 /** Invite link for a room code (current page URL with ?room=CODE). */
 export function inviteLink(code) {
   const loc = globalThis.location;
@@ -189,6 +202,21 @@ function DifficultyPicker({ room, isHost, busy, onPick }) {
   </div>`;
 }
 
+/** The 「AI 队友最后选择」 switch (co-op): the host toggles it, everybody else sees its state. */
+function AiLastToggle({ option, busy, onToggle }) {
+  if (!option) return null;
+  return html`<div class="ailast">
+    <${Tooltip} text=${t('策略与机变轮选时，所有博士先于 AI 队友选择')}>
+      <button type="button" role="switch" aria-checked=${option.on ? 'true' : 'false'}
+          class=${`dpick__opt ailast__opt${option.on ? ' is-active' : ''}`} disabled=${!option.editable || !!busy}
+          onClick=${() => option.editable && onToggle(!option.on)}>
+        <${Icon} name="check" class=${option.on ? 'is-on' : ''} />${t('AI 队友最后选择')}
+      </button>
+    <//>
+    ${option.editable ? null : html`<span class="t-dim">${t('由创建者设置')}</span>`}
+  </div>`;
+}
+
 /** Room screen component. */
 export function RoomScreen() {
   const room = useStore((s) => s.room);
@@ -229,6 +257,7 @@ export function RoomScreen() {
     if (ok) run(`kick${seat}`, () => net.request('room.kick', { seat, playerId }));
   };
   const setDifficulty = (difficulty) => run('diff', () => net.request('room.setDifficulty', { difficulty }));
+  const setAiLast = (on) => run('ailast', () => net.request('room.setAiPicksLast', { on }));
   // spectator seats: the host frees one; a spectator takes a free player seat with room.join of this room
   const removeSpectator = (playerId) => run(`rs${playerId}`, () => net.request('room.removeSpectator', { playerId }));
   const sit = () => run('sit', () => net.request('room.join', { code: room.code }));
@@ -307,7 +336,10 @@ export function RoomScreen() {
     <footer class="room-bar">
       <div class="room-bar__left">
         <span class="room-bar__label">${t('模拟难度')}<${MicroLabel}>DIFFICULTY<//></span>
-        <${DifficultyPicker} room=${room} isHost=${facts.isHost} busy=${busy} onPick=${setDifficulty} />
+        <div class="room-bar__opts">
+          <${DifficultyPicker} room=${room} isHost=${facts.isHost} busy=${busy} onPick=${setDifficulty} />
+          <${AiLastToggle} option=${aiLastOption(room, me.playerId)} busy=${busy} onToggle=${setAiLast} />
+        </div>
       </div>
       <div class="room-bar__center">
         <div class="ready-count" hidden=${!coop}>

server/lobby.js

@@ -8,9 +8,10 @@
 //     Humans and bots take the lowest free seat index; seat indexes never compact.
 //   * ▸ Being in a LOBBY room and sending room.create / room.join implicitly leaves it. While your room is
 //     in a match, create/join of another room fails with ROOM_STARTED (send g.leave or room.leave first).
-//   * Host-only: room.setDifficulty, room.addBot, room.removeBot, room.kick, room.start. ▸ Changing the difficulty
-//     un-readies the other humans. ▸ room.start requires every other human to be connected and ready;
-//     the host's start counts as the host's ready (the host may still toggle room.ready for display).
+//   * Host-only: room.setDifficulty, room.setAiPicksLast, room.addBot, room.removeBot, room.kick, room.start.
+//     ▸ Changing the difficulty or the AI-picks-last option (co-op only) un-readies the other humans.
+//     ▸ room.start requires every other human to be connected and ready; the host's start counts as the host's
+//     ready (the host may still toggle room.ready for display).
 //   * room.kick {seat, playerId} (community report #17, owner approved): before the match only, the host removes another
 //     human like an AI seat (an AI seat stays room.removeBot's; never the host itself). `playerId` names the player the
 //     host confirmed: a seat that changed hands meanwhile (left, someone else joined) is refused with BAD_TARGET. The
@@ -37,10 +38,10 @@
 //     that window coalesce into one deferred resync, so hello spam cannot amplify into ~15 KB per request.
 //   * Result replay: the match's final m.public and each human's m.result are kept after the match ends. A
 //     human who resyncs (resume after a drop, a reloaded tab, a repeated hello) while the room is back in LOBBY
-//     gets room.state followed by those two frames again, until they act in the room (ready, difficulty, AI
-//     seats, start), leave it, or a new match starts. A human removed by the lobby grace gets them right after
-//     `room.closed {timeout}` on their next resume (Match.onReconnect cannot do this: the lobby drops the
-//     match reference at onEnd and disposes it on the next macrotask).
+//     gets room.state followed by those two frames again, until they act in the room (ready, difficulty, the
+//     AI-picks-last option, AI seats, start), leave it, or a new match starts. A human removed by the lobby grace
+//     gets them right after `room.closed {timeout}` on their next resume (Match.onReconnect cannot do this: the
+//     lobby drops the match reference at onEnd and disposes it on the next macrotask).
 //   * Per-network limits (internet clients only, see net.js clientAddress): at most `maxRoomsPerAddr` rooms
 //     created from one network may exist at once and at most `maxMatchesPerAddr` matches started from one
 //     network may run at once (room.create / room.start → ERR.RATE). Without them a socket loop could fill
@@ -153,6 +154,11 @@ export class Room {
     this.code = code;
     this.mode = mode;
     this.difficulty = difficulty;
+    /**
+     * 「AI 队友最后选择」 (room.setAiPicksLast, GitHub #338; co-op only, off by default): the match's strategy and 机变 drafts
+     * put every human seat before every AI seat (Match opts.aiPicksLast). Kept across the room's matches.
+     */
+    this.aiPicksLast = false;
     /** @type {string | null} */
     this.hostId = null;
     /** @type {(Seat | null)[]} */
@@ -202,6 +208,7 @@ export class Room {
       hostId: this.hostId,
       mode: this.mode,
       difficulty: this.difficulty,
+      aiPicksLast: this.aiPicksLast,
       inMatch: !!this.match,
       seats: this.seats.map((s) => (s
         ? { seat: s.seat, playerId: s.playerId, name: s.name, isBot: s.isBot, ready: s.ready, connected: s.connected && !s.left }
@@ -311,6 +318,7 @@ export class Lobby {
       case 'room.leave': return this.leave(session);
       case 'room.ready': return this.ready(session, msg);
       case 'room.setDifficulty': return this.setDifficulty(session, msg);
+      case 'room.setAiPicksLast': return this.setAiPicksLast(session, msg);
       case 'room.addBot': return this.addBot(session);
       case 'room.removeBot': return this.removeBot(session, msg);
       case 'room.kick': return this.kick(session, msg);
@@ -499,6 +507,22 @@ export class Lobby {
     return OK;
   }
 
+  /** 「AI 队友最后选择」 (GitHub #338): host-only, before the match, co-op rooms only (a solo room has no AI seat). */
+  setAiPicksLast(session, { on }) {
+    const room = this.roomOf(session);
+    if (!room) return fail(ERR.NOT_IN_ROOM);
+    if (room.hostId !== session.playerId) return fail(ERR.NOT_HOST);
+    if (room.match) return fail(ERR.ROOM_STARTED);
+    if (room.mode === 'solo') return fail(ERR.BAD_TARGET, 'solo rooms have no AI teammates');
+    this.dropReplay(room, session.playerId);
+    if (room.aiPicksLast !== on) {
+      room.aiPicksLast = on;
+      for (const s of room.seats) if (s && !s.isBot && s.playerId !== room.hostId) s.ready = false;
+      this.broadcastState(room);
+    }
+    return OK;
+  }
+
   addBot(session) {
     const room = this.roomOf(session);
     if (!room) return fail(ERR.NOT_IN_ROOM);
@@ -672,6 +696,8 @@ export class Lobby {
         mode: room.mode,
         difficulty: room.difficulty,
         modeId: modeIdFor(room.mode, room.difficulty),
+        // 「AI 队友最后选择」 (GitHub #338): fixed for the match
+        aiPicksLast: room.mode !== 'solo' && room.aiPicksLast === true,
         seats,
         // the spectator seats (header): watched like eliminated players, never players
         spectators: room.spectators.map((s) => s.playerId),

server/match/Match.js

@@ -12,6 +12,9 @@
 //   opts.mode        'solo' | 'coop'
 //   opts.difficulty  'FUNNY'|'NORMAL'|'HARD'|'ABYSS'
 //   opts.modeId      string                     modeIdFor(mode, difficulty), e.g. 'mode_multi_hard'
+//   opts.aiPicksLast boolean (optional)         the co-op room option 「AI 队友最后选择」 (room.setAiPicksLast, GitHub #338):
+//                                              the strategy and 机变 drafts put every human seat before every AI seat
+//                                              (MatchPhases.humansFirst); only `true` turns it on; ignored in solo
 //   opts.seats       Array<{ seat: 0..3, playerId: string, name: string, isBot: boolean, connected: boolean,
 //                            loadout?: { [baseChessId]: { skill: index, module: uniEquipId|'none'|null } } | null,
 //                            notOwned?: string[] | null,
@@ -236,6 +239,8 @@ export class Match {
     this.gd = new GameData(this.data, this.modeId);
     if (!this.difficulty) this.difficulty = this.gd.difficulty;
     this.isSolo = this.mode === 'solo' || this.gd.isSolo;
+    /** 「AI 队友最后选择」 (opts.aiPicksLast, GitHub #338): humans draft before AI seats (MatchPhases.humansFirst) */
+    this.aiPicksLast = !this.isSolo && opts.aiPicksLast === true;
     this.ownsScheduler = !opts.scheduler;
     this.sched = opts.scheduler || new RealScheduler({ now: opts.now || Date.now, onError: (e) => this.reportError('timer', e) });
     this.registry = opts.registry || getDefaultRegistry();

server/match/match/phases.js

@@ -40,8 +40,9 @@ export class MatchPhases {
   enterBandDraft() {
     if (this.phase !== PHASE.INFO_CHECK) return;
     this.phase = PHASE.BAND_DRAFT;
-    const order = this.order.map((p) => p.playerId);
+    let order = this.order.map((p) => p.playerId);
     if (!this.isSolo) this.rngDraft.shuffle(order);
+    order = this.humansFirst(order);
     const skips = this.isSolo ? 0 : this.gd.bandDraft.skipsPerPlayer;
     const untimed = this.soloUntimed;
     this.draft = {
@@ -54,6 +55,22 @@ export class MatchPhases {
     this.markPublic();
   }
 
+  /**
+   * The co-op room option 「AI 队友最后选择」 (this.aiPicksLast, GitHub #338): every human seat before every AI seat, each
+   * group in the order the draft drew (a stable partition applied AFTER the shuffle — no extra random draw: the order
+   * with the option off is unchanged, and with it on every random stream stands where it would without it; only the
+   * picks made in the new order can differ). A human is any seat that is not an AI seat (room.addBot): under AI 托管,
+   * disconnected or departed it still counts as a human. Used by the strategy draft and the 机变 draft
+   * (MatchSpDraft.enterSpDraft).
+   * @param {string[]} order playerIds in drawn order
+   * @returns {string[]}
+   */
+  humansFirst(order) {
+    if (!this.aiPicksLast) return order;
+    const bot = (pid) => !!this.players.get(pid)?.isBot;
+    return [...order.filter((pid) => !bot(pid)), ...order.filter(bot)];
+  }
+
   draftTurn() {
     const d = this.draft;
     if (!d) return null;
@@ -194,7 +211,16 @@ export class MatchPhases {
     if (d.order.length - d.idx <= 1) return fail(ERR.BAD_TARGET, 'nobody to pass to');
     d.skipsLeft[ps.playerId]--;
     d.order.splice(d.idx, 1);
-    d.order.push(ps.playerId);
+    // the skipper goes to the end; with 「AI 队友最后选择」 to the end of the humans still to pick — behind them, ahead of
+    // the AI seats — and to the very end only when no other human is left to pass to [ASSUMED: the option's intent,
+    // humans before AI, kept through a skip; no source, a remake option]
+    let at = d.order.length;
+    if (this.aiPicksLast) {
+      for (let j = d.order.length - 1; j >= d.idx; j--) {
+        if (!this.players.get(d.order[j])?.isBot) { at = j + 1; break; }
+      }
+    }
+    d.order.splice(at, 0, ps.playerId);
     this.startDraftTurn();
     return OK;
   }

server/match/match/spDraft.js

@@ -15,8 +15,10 @@ export class MatchSpDraft {
     const alive = this.alivePlayers();
     if (!draft || !alive.length) { this.enterPrep(); return; }
     this.phase = PHASE.SP_DRAFT;
-    const order = alive.map((p) => p.playerId);
+    let order = alive.map((p) => p.playerId);
     if (!this.isSolo) this.rngDraft.shuffle(order);
+    // 「AI 队友最后选择」 (GitHub #338): humans before AI seats, after the same shuffle (MatchPhases.humansFirst)
+    order = this.humansFirst(order);
     // untimed: solo and any single-human match (soloUntimed); the co-op order / 6 cards stay
     const untimed = this.soloUntimed;
     this.sp = { ...draft, order, idx: 0, picks: {}, taken: {}, untimed, turnDeadline: 0 };

shared/protocol.js

@@ -325,6 +325,9 @@ export const C2S = {
   'room.leave': {},
   'room.ready': { ready: isBool },
   'room.setDifficulty': { difficulty: (v) => DIFFICULTIES.includes(v) },
+  // the co-op room option 「AI 队友最后选择」 (GitHub #338; host, before the match): the strategy and 机变 drafts order every
+  // human seat before every AI seat (server/match/match/phases.js humansFirst); room.state.aiPicksLast
+  'room.setAiPicksLast': { on: isBool },
   'room.addBot': {},
   'room.removeBot': { seat: (v) => isInt(v, 0, MAX_SEATS - 1) },
   // the host removes another human before the match (server/lobby.js kick; community report #17); playerId = the one the

test/lobby-ai-last.test.js

@@ -0,0 +1,145 @@
+// test/lobby-ai-last.test.js — the co-op room option 「AI 队友最后选择」 (room.setAiPicksLast {on}; GitHub #338): host-only,
+// before the match only, co-op rooms only, off by default; room.state.aiPicksLast shows it to everybody; the match gets
+// it as opts.aiPicksLast when it starts (server/match/Match.js orders the drafts with it — test/match/ai-picks-last.test.js).
+import { describe, test, before, after, afterEach } from 'node:test';
+import assert from 'node:assert/strict';
+
+import { startServer } from '../server/index.js';
+import { StubMatch } from '../server/match/StubMatch.js';
+import { TestClient } from './helpers/wsClient.js';
+import { ERR } from '../shared/constants.js';
+import { validateC2S } from '../shared/protocol.js';
+
+function clientPool(getUrl) {
+  const open = new Set();
+  return {
+    async connect() { const c = await TestClient.connect(getUrl()); open.add(c); return c; },
+    async player(name, token) {
+      const c = await this.connect();
+      const w = await c.hello(name, token);
+      c.id = w.playerId;
+      c.token = w.token;
+      return c;
+    },
+    async closeAll() {
+      await Promise.all([...open].map((c) => c.terminate().catch(() => {})));
+      open.clear();
+    },
+  };
+}
+const quietLog = () => {
+  const errors = [];
+  return { errors, log: { info() {}, warn() {}, debug() {}, error: (...a) => errors.push(a.map(String).join(' ')) } };
+};
+const ok = async (c, msg) => { const r = await c.request(msg); assert.equal(r.t, 'ok', `${msg.t}: ${JSON.stringify(r)}`); return r; };
+const err = async (c, msg, code) => { const r = await c.request(msg); assert.equal(r.t, 'error', JSON.stringify(r)); assert.equal(r.code, code, JSON.stringify(r)); return r; };
+const seatOf = (state, id) => state.seats.find((s) => s && s.playerId === id) || null;
+async function createRoom(c, mode = 'coop') {
+  await ok(c, { t: 'room.create', mode, difficulty: 'NORMAL' });
+  return c.waitFor('room.state', (s) => s.hostId === c.id && s.mode === mode);
+}
+async function joinRoom(c, code) {
+  await ok(c, { t: 'room.join', code });
+  return c.waitFor('room.state', (s) => s.code === code && !!seatOf(s, c.id));
+}
+
+/** StubMatch that records the options each match was started with. */
+const started = [];
+class RecordingMatch extends StubMatch {
+  constructor(opts) {
+    super(opts);
+    started.push(opts);
+  }
+}
+
+test('protocol: room.setAiPicksLast takes exactly a boolean `on`', () => {
+  assert.equal(validateC2S({ t: 'room.setAiPicksLast', on: true }), null);
+  assert.equal(validateC2S({ t: 'room.setAiPicksLast', on: false }), null);
+  for (const on of [undefined, null, 1, 0, 'true', 'yes', {}, []]) {
+    assert.notEqual(validateC2S({ t: 'room.setAiPicksLast', on }), null, JSON.stringify(on));
+  }
+});
+
+describe('room.setAiPicksLast (lobby)', () => {
+  let srv;
+  let pool;
+  const cap = quietLog();
+  before(async () => {
+    srv = await startServer({ port: 0, host: '127.0.0.1', log: cap.log, MatchClass: RecordingMatch, lobbyGraceMs: 60_000 });
+    pool = clientPool(() => `ws://127.0.0.1:${srv.port}/ws`);
+  });
+  afterEach(async () => { await pool.closeAll(); });
+  after(async () => {
+    await srv?.close();
+    assert.deepEqual(cap.errors, [], 'no server errors logged');
+  });
+
+  test('off by default; host-only; every seat sees it in room.state; a change un-readies the guests like the difficulty', async () => {
+    const host = await pool.player('Host');
+    const st = await createRoom(host);
+    assert.equal(st.aiPicksLast, false);
+    const guest = await pool.player('Guest');
+    const js = await joinRoom(guest, st.code);
+    assert.equal(js.aiPicksLast, false);
+    await err(guest, { t: 'room.setAiPicksLast', on: true }, ERR.NOT_HOST);
+    await ok(guest, { t: 'room.ready', ready: true });
+    await host.waitFor('room.state', (s) => seatOf(s, guest.id)?.ready);
+    await ok(host, { t: 'room.setAiPicksLast', on: true });
+    const on = await guest.waitFor('room.state', (s) => s.aiPicksLast === true);
+    assert.equal(seatOf(on, guest.id).ready, false, 'the rules changed: the guest confirms again');
+    await host.waitFor('room.state', (s) => s.aiPicksLast === true);
+    // the same value again changes nothing (no broadcast needed, still ok)
+    await ok(host, { t: 'room.setAiPicksLast', on: true });
+    await ok(host, { t: 'room.setAiPicksLast', on: false });
+    await guest.waitFor('room.state', (s) => s.aiPicksLast === false);
+    // a malformed value never reaches the lobby
+    await err(host, { t: 'room.setAiPicksLast', on: 'yes' }, ERR.BAD_MSG);
+  });
+
+  test('solo rooms have no AI teammates: refused, the state stays off', async () => {
+    const host = await pool.player('Solo');
+    const st = await createRoom(host, 'solo');
+    assert.equal(st.aiPicksLast, false);
+    await err(host, { t: 'room.setAiPicksLast', on: true }, ERR.BAD_TARGET);
+  });
+
+  test('the match gets it at the start; it cannot change during the match; the room keeps it for the next match and a new host', async () => {
+    const host = await pool.player('Host');
+    const st = await createRoom(host);
+    const guest = await pool.player('Guest');
+    await joinRoom(guest, st.code);
+    await ok(host, { t: 'room.addBot' });
+    await ok(host, { t: 'room.setAiPicksLast', on: true });
+    await ok(guest, { t: 'room.ready', ready: true });
+    await host.waitFor('room.state', (s) => s.aiPicksLast && seatOf(s, guest.id)?.ready);
+    const n = started.length;
+    await ok(host, { t: 'room.start' });
+    await guest.waitFor('room.state', (s) => s.inMatch && s.aiPicksLast === true);
+    assert.equal(started.length, n + 1);
+    assert.equal(started[n].aiPicksLast, true, 'opts.aiPicksLast');
+    await err(host, { t: 'room.setAiPicksLast', on: false }, ERR.ROOM_STARTED);
+    await err(guest, { t: 'room.setAiPicksLast', on: false }, ERR.NOT_HOST);
+    // the stub match ends once every human confirmed the briefing → back in the lobby with the option kept
+    guest.clearInbox();
+    await ok(host, { t: 'g.infoReady' });
+    await ok(guest, { t: 'g.infoReady' });
+    const back = await guest.waitFor('room.state', (s) => !s.inMatch);
+    assert.equal(back.aiPicksLast, true);
+    // host migration keeps the room's settings
+    await ok(host, { t: 'room.leave' });
+    const migrated = await guest.waitFor('room.state', (s) => s.hostId === guest.id);
+    assert.equal(migrated.aiPicksLast, true);
+    await ok(guest, { t: 'room.setAiPicksLast', on: false });
+    await guest.waitFor('room.state', (s) => s.aiPicksLast === false);
+  });
+
+  test('without the option the match gets aiPicksLast false', async () => {
+    const host = await pool.player('Host');
+    await createRoom(host);
+    await ok(host, { t: 'room.addBot' });
+    const n = started.length;
+    await ok(host, { t: 'room.start' });
+    await host.waitFor('room.state', (s) => s.inMatch);
+    assert.equal(started[n].aiPicksLast, false);
+  });
+});

test/match/ai-picks-last.test.js

@@ -0,0 +1,208 @@
+// The co-op room option 「AI 队友最后选择」 (opts.aiPicksLast; GitHub #338): in the strategy draft (BAND_DRAFT) and the
+// 机变 draft (SP_DRAFT) every human seat picks before every AI seat. The drawn order is kept inside each group (a stable
+// partition AFTER the usual shuffle): no extra random draw, so the option off is today's order and the option on moves
+// no random stream. A human under AI 托管, disconnected or departed is still a human (only room.addBot seats are AI).
+// A human's skip passes the turn to the other humans still to pick, ahead of the AI seats [ASSUMED]; with no other
+// human left it goes to the end as without the option.
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { PHASE } from '../../shared/constants.js';
+import { makeMatch } from './harness.js';
+
+const isAi = (pid) => pid.startsWith('ai_');
+/** the stable humans-first partition of a drawn order */
+const humansFirst = (order) => [...order.filter((p) => !isAi(p)), ...order.filter(isAi)];
+/** humans first, then AI seats, each in seat order — 1 host + 3 AI by default */
+const seatsOf = (ids) => ids.map((playerId, seat) => ({ seat, playerId, name: playerId, isBot: isAi(playerId), connected: true }));
+
+/** A match driven to BAND_DRAFT (every human confirms the briefing); `before(m)` runs while still in INFO_CHECK. */
+function toBandDraft(o, before) {
+  const h = makeMatch({ mode: 'coop', ...o }).start();
+  if (before) before(h.m);
+  for (const ps of h.m.players.values()) if (!ps.isBot && !ps.left) h.m.handle(ps.playerId, { t: 'g.infoReady' });
+  h.run(() => h.m.phase !== PHASE.INFO_CHECK);
+  assert.equal(h.m.phase, PHASE.BAND_DRAFT);
+  return h;
+}
+
+/** The band-draft order (taken at its start, before any skip) and the next draws of the random streams after it. */
+function bandOrder(o, before) {
+  const h = toBandDraft(o, before);
+  const order = h.m.draft.order.slice();
+  const draws = { draft: h.m.rngDraft(), shop: h.m.rngShop(), bots: h.m.rngBots(), meta: h.m.rngMeta(), waves: h.m.rngWaves() };
+  h.m.dispose();
+  return { order, draws };
+}
+
+test('the option: off by default, on only when opts.aiPicksLast === true, never in solo', () => {
+  const mk = (o) => { const h = makeMatch(o); const v = h.m.aiPicksLast; h.m.dispose(); return v; };
+  assert.equal(mk({ mode: 'coop', humans: 1, bots: 3 }), false);
+  assert.equal(mk({ mode: 'coop', humans: 1, bots: 3, aiPicksLast: true }), true);
+  assert.equal(mk({ mode: 'coop', humans: 1, bots: 3, aiPicksLast: 'yes' }), false, 'only a real boolean');
+  assert.equal(mk({ mode: 'solo', humans: 1, aiPicksLast: true }), false, 'solo: nothing to order');
+});
+
+test('band draft, option off: the order is exactly today\'s for the same seed (no option = off)', () => {
+  let humanNotFirst = 0;
+  for (let seed = 1; seed <= 12; seed++) {
+    const o = { seats: seatsOf(['p_0', 'ai_0', 'ai_1', 'ai_2']), seed };
+    const def = bandOrder(o);
+    const off = bandOrder({ ...o, aiPicksLast: false });
+    assert.deepEqual(off, def, `seed ${seed}`);
+    if (def.order[0] !== 'p_0') humanNotFirst++;
+  }
+  assert.ok(humanNotFirst > 0, 'the shuffle does put an AI first without the option (so the next test means something)');
+});
+
+test('band draft, option on, 1 human + 3 AI: the human always picks first; the same shuffle, every random stream unchanged', () => {
+  for (let seed = 1; seed <= 12; seed++) {
+    const o = { seats: seatsOf(['p_0', 'ai_0', 'ai_1', 'ai_2']), seed };
+    const off = bandOrder(o);
+    const on = bandOrder({ ...o, aiPicksLast: true });
+    assert.equal(on.order[0], 'p_0', `seed ${seed}`);
+    assert.deepEqual(on.order, humansFirst(off.order), `seed ${seed}: the AI seats keep their drawn order`);
+    assert.deepEqual(on.draws, off.draws, `seed ${seed}: no extra random draw`);
+  }
+});
+
+test('band draft, option on, 2 humans + 2 AI on interleaved seats: both humans first, in their drawn order', () => {
+  const ids = ['p_0', 'ai_0', 'p_1', 'ai_1'];
+  const seen = new Set();
+  for (let seed = 1; seed <= 12; seed++) {
+    const o = { seats: seatsOf(ids), seed };
+    const off = bandOrder(o);
+    const on = bandOrder({ ...o, aiPicksLast: true });
+    assert.deepEqual(on.order, humansFirst(off.order), `seed ${seed}`);
+    assert.deepEqual(on.order.slice(0, 2).sort(), ['p_0', 'p_1']);
+    seen.add(on.order[0]);
+  }
+  assert.equal(seen.size, 2, 'the humans\' own order is still drawn (either may lead)');
+});
+
+test('band draft, option on: all humans, or all AI seats (tools/matchrun), keep today\'s order', () => {
+  for (const ids of [['p_0', 'p_1', 'p_2', 'p_3'], ['ai_0', 'ai_1', 'ai_2', 'ai_3']]) {
+    for (let seed = 1; seed <= 4; seed++) {
+      const o = { seats: seatsOf(ids), seed };
+      if (ids[0] === 'ai_0') {
+        // no human: INFO_CHECK ends by itself
+        const run = (x) => { const h = makeMatch({ mode: 'coop', ...x }).start(); h.run(() => h.m.phase !== PHASE.INFO_CHECK); const r = h.m.draft.order.slice(); h.m.dispose(); return r; };
+        assert.deepEqual(run({ ...o, aiPicksLast: true }), run(o), `all AI, seed ${seed}`);
+      } else {
+        assert.deepEqual(bandOrder({ ...o, aiPicksLast: true }), bandOrder(o), `all humans, seed ${seed}`);
+      }
+    }
+  }
+});
+
+test('band draft, option on: a human under AI 托管, disconnected or departed is still ordered as a human', () => {
+  for (let seed = 1; seed <= 8; seed++) {
+    const o = { seats: seatsOf(['p_0', 'p_1', 'p_2', 'ai_0']), seed, aiPicksLast: true };
+    const before = (m) => {
+      m.handle('p_0', { t: 'g.autoplay', on: true });
+      m.onDisconnect('p_1');
+      m.onLeave('p_2');
+    };
+    const h = toBandDraft(o, before);
+    assert.equal(h.m.draft.order[3], 'ai_0', `seed ${seed}: ${h.m.draft.order}`);
+    h.m.dispose();
+  }
+});
+
+test('band draft, option on: a skip passes the turn to the other humans, ahead of the AI seats; the last human\'s skip goes to the end [ASSUMED]', () => {
+  const h = toBandDraft({ seats: seatsOf(['p_0', 'ai_0', 'p_1', 'ai_1']), seed: 3, aiPicksLast: true });
+  const m = h.m;
+  const [h1, h2, a1, a2] = m.draft.order;
+  assert.ok(!isAi(h1) && !isAi(h2) && isAi(a1) && isAi(a2), String(m.draft.order));
+  // the first human passes: behind the other human, still before the AI seats
+  assert.deepEqual(m.handle(h1, { t: 'g.bandSkip' }), { ok: true });
+  assert.deepEqual(m.draft.order, [h2, h1, a1, a2]);
+  assert.equal(m.draftTurn(), h2);
+  // the second human passes: behind the first again
+  assert.deepEqual(m.handle(h2, { t: 'g.bandSkip' }), { ok: true });
+  assert.deepEqual(m.draft.order, [h1, h2, a1, a2]);
+  assert.deepEqual(m.handle(h1, { t: 'g.band', bandId: 'band_amiya' }), { ok: true });
+  assert.equal(m.draftTurn(), h2);
+  m.dispose();
+
+  // a lone human (host + AI): no other human to pass to — the skip moves it to the end as without the option
+  const h3 = toBandDraft({ seats: seatsOf(['p_0', 'ai_0', 'ai_1', 'ai_2']), seed: 3, aiPicksLast: true });
+  const order = h3.m.draft.order.slice();
+  assert.equal(order[0], 'p_0');
+  assert.deepEqual(h3.m.handle('p_0', { t: 'g.bandSkip' }), { ok: true });
+  assert.deepEqual(h3.m.draft.order, [...order.slice(1), 'p_0']);
+  h3.m.dispose();
+
+  // option off: the skip still goes to the very end (today's rule)
+  const h4 = toBandDraft({ seats: seatsOf(['p_0', 'ai_0', 'p_1', 'ai_1']), seed: 3 });
+  h4.run(() => !isAi(h4.m.draftTurn() || 'ai_'));
+  const o4 = h4.m.draft.order.slice();
+  const at = h4.m.draft.idx;
+  const cur = h4.m.draftTurn();
+  assert.deepEqual(h4.m.handle(cur, { t: 'g.bandSkip' }), { ok: true });
+  assert.deepEqual(h4.m.draft.order, [...o4.slice(0, at), ...o4.slice(at + 1), cur]);
+  h4.m.dispose();
+});
+
+/** Drive a fake-battle match into the SP draft of round `r`; `flip(m)` runs just before it is entered. */
+function toSpDraft(o, r, flip) {
+  const h = makeMatch({ mode: 'coop', difficulty: 'NORMAL', fake: true, ...o }).start();
+  const m = h.m;
+  h.drive(() => m.phase === PHASE.ROUND_START && m.round === r);
+  assert.equal(m.round, r);
+  if (flip) flip(m);
+  h.run(() => m.phase === PHASE.SP_DRAFT);
+  assert.equal(m.phase, PHASE.SP_DRAFT);
+  return h;
+}
+
+test('机变 draft, option off vs on from the same state: on = the humans-first partition of the same shuffle; no random stream moves', () => {
+  for (const [ids, seed] of [[['p_0', 'ai_0', 'ai_1', 'ai_2'], 14], [['p_0', 'ai_0', 'p_1', 'ai_1'], 5], [['p_0', 'ai_0', 'ai_1', 'ai_2'], 2]]) {
+    const o = { seats: seatsOf(ids), seed };
+    const off = toSpDraft(o, 3);
+    const on = toSpDraft(o, 3, (m) => { m.aiPicksLast = true; });
+    assert.deepEqual(on.m.sp.order, humansFirst(off.m.sp.order), `seed ${seed}`);
+    assert.deepEqual(on.m.sp.cards, off.m.sp.cards, 'the same cards');
+    for (const k of ['rngDraft', 'rngShop', 'rngBots', 'rngMeta', 'rngWaves']) assert.equal(on.m[k](), off.m[k](), `${k} unchanged (seed ${seed})`);
+    off.m.dispose();
+    on.m.dispose();
+  }
+});
+
+test('机变 draft, option on, 1 human + 3 AI: the human picks first in every 机变 round of the match', () => {
+  for (const seed of [1, 14]) {
+    const h = makeMatch({ mode: 'coop', difficulty: 'NORMAL', fake: true, seats: seatsOf(['p_0', 'ai_0', 'ai_1', 'ai_2']), seed, aiPicksLast: true }).start();
+    const m = h.m;
+    const firsts = {};
+    const enter = m.enterSpDraft;
+    m.enterSpDraft = function () {
+      enter.call(this);
+      if (this.sp) firsts[this.round] = this.sp.order[0];
+    };
+    h.drive(() => h.ended != null || m.round > 9);
+    const rounds = m.gd.spRounds().filter((r) => r <= 9);
+    assert.deepEqual(rounds, [3, 6, 9]);
+    for (const r of rounds) if (firsts[r] != null) assert.equal(firsts[r], 'p_0', `seed ${seed} R${r}`);
+    assert.ok(firsts[3] === 'p_0', 'round 3 is always reached');
+    m.dispose();
+  }
+});
+
+test('机变 draft, option on, 2 humans + 2 AI interleaved, one under AI 托管: both humans ahead of the AI seats', () => {
+  const o = { seats: seatsOf(['p_0', 'ai_0', 'p_1', 'ai_1']), seed: 5 };
+  const h = toSpDraft({ ...o, aiPicksLast: true }, 3, (m) => { m.handle('p_1', { t: 'g.autoplay', on: true }); });
+  assert.deepEqual(h.m.sp.order.slice(0, 2).sort(), ['p_0', 'p_1']);
+  assert.ok(h.m.sp.order.slice(2).every(isAi));
+  h.m.dispose();
+});
+
+test('solo: the option changes nothing (seat order, no skip)', () => {
+  const run = (aiPicksLast) => {
+    const h = makeMatch({ mode: 'solo', humans: 1, seed: 7, aiPicksLast }).start();
+    h.m.handle('p_0', { t: 'g.infoReady' });
+    h.run(() => h.m.phase !== PHASE.INFO_CHECK);
+    const r = { order: h.m.draft.order.slice(), next: h.m.rngDraft() };
+    h.m.dispose();
+    return r;
+  };
+  assert.deepEqual(run(true), run(undefined));
+});

test/match/harness.js

@@ -7,7 +7,8 @@
 // seed, matchNo (the room's match number: part of the battleId prefix), data (default: real data/*.json),
 // fake (true → test/match/fakeBattle.js as BattleClass), script (FakeBattle.script), registry, instant (virtual
 // scheduler runs battles synchronously; default true), timerScale, battleContent, botRehearsal (default 0),
-// botSliceMs (bot rehearsal slice budget; default: unbounded in virtual time).
+// botSliceMs (bot rehearsal slice budget; default: unbounded in virtual time), aiPicksLast (the room option
+// AI 队友最后选择: the drafts order every human seat before every AI seat).
 // Combat mode: clientCombat (default false here: the legacy server-run mode most suites were written for; production
 // defaults to client-side combat, DESIGN §14). With clientCombat: true every human gets a scripted browser
 // (test/match/simClient.js SimClient: h.clients) unless clients: false; pace 'instant' | 'paced', perPlayer
@@ -77,6 +78,7 @@ export function makeMatch(o = {}) {
     clientCombat: o.clientCombat ?? false,
     verify: o.verify ?? 'off',
     headlessSliceMs: o.headlessSliceMs,
+    aiPicksLast: o.aiPicksLast,
   });
   const m = h.m;
   if (m.clientCombat && o.clients !== false) {

test/ui/ai-picks-last.test.js

@@ -0,0 +1,38 @@
+// The room screen's 「AI 队友最后选择」 switch (GitHub #338; server: room.setAiPicksLast, room.state.aiPicksLast): co-op
+// rooms only, the host toggles it, everybody else sees its state read-only; the texts go through t() with English in
+// public/i18n/en.json.
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath, pathToFileURL } from 'node:url';
+
+const ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '../..');
+const SRC = readFileSync(path.join(ROOT, 'public/js/screens/room.js'), 'utf8');
+const EN = JSON.parse(readFileSync(path.join(ROOT, 'public/i18n/en.json'), 'utf8'));
+const mod = () => import(pathToFileURL(path.join(ROOT, 'public/js/screens/room.js')).href);
+
+const room = (o = {}) => ({
+  code: 'ABCD', hostId: 'h', mode: 'coop', difficulty: 'NORMAL', aiPicksLast: false,
+  seats: [{ seat: 0, playerId: 'h', name: 'Host', isBot: false, ready: false, connected: true }, { seat: 1, playerId: 'g', name: 'G', isBot: false, ready: false, connected: true }, null, null],
+  ...o,
+});
+
+test('aiLastOption: hidden in solo, editable by the host only, the state from room.state (off when absent)', async () => {
+  const { aiLastOption } = await mod();
+  assert.equal(aiLastOption(room({ mode: 'solo' }), 'h'), null, 'solo: no AI teammates');
+  assert.deepEqual(aiLastOption(room(), 'h'), { on: false, editable: true });
+  assert.deepEqual(aiLastOption(room({ aiPicksLast: true }), 'h'), { on: true, editable: true });
+  assert.deepEqual(aiLastOption(room({ aiPicksLast: true }), 'g'), { on: true, editable: false });
+  assert.deepEqual(aiLastOption(room({ aiPicksLast: undefined }), 'g'), { on: false, editable: false }, 'an older server');
+  assert.equal(aiLastOption(null, 'h'), null);
+});
+
+test('room.js sends room.setAiPicksLast { on } and shows the switch through t(); en.json has the English', () => {
+  assert.match(SRC, /net\.request\('room\.setAiPicksLast', \{ on \}\)/);
+  for (const zh of ['AI 队友最后选择', '策略与机变轮选时，所有博士先于 AI 队友选择', '由创建者设置']) {
+    assert.ok(SRC.includes(`t('${zh}')`), zh);
+    assert.equal(typeof EN[zh], 'string', `en.json: ${zh}`);
+    assert.ok(EN[zh].length > 0 && !/[一-鿿]/.test(EN[zh]), `English for ${zh}`);
+  }
+});