explodorama / files / src / sim / replayCompare.ts
replayCompare.ts
351348d1 2026-11-04 Pavel Safronov | 1 | import { autopilotPlan } from './autopilot' |
| 2 | import { predictDanger } from './danger' | |
| 3 | import { newRun } from './state' | |
| 4 | import { step } from './turn' | |
| 5 | import { SIM_VERSION, type RunRecord } from './record' | |
| 6 | import type { Action, GameState } from './types' | |
| 7 | ||
| 8 | /** | |
| 9 | * A bug report's run, set against what today's autopilot does from the same place (Q103, user | |
| 10 | * request, 2026-11-03): the dev replay page (`?replay=` in `main.ts`) plays two players side by | |
| 11 | * side, one turn each at a time, in a loop: red plays `prefix` then `old` (the report), blue plays | |
| 12 | * `prefix` then `neu` (today's autopilot). | |
| 13 | */ | |
| 14 | export interface ReplayScript { | |
| 15 | /** The room as it stood `lead` turns before the autopilot took over. */ | |
| 16 | start: GameState | |
| 17 | /** Turns both share: from `start` to the moment the last enemy died (the autopilot took over). */ | |
| 18 | prefix: Action[] | |
| 19 | /** What the report did from there on, and a few waits after it to show how it ends. */ | |
| 20 | old: Action[] | |
| 21 | /** What today's autopilot does from there on, to as long as the report went, a few turns more. */ | |
| 22 | neu: Action[] | |
| 23 | /** How each fork ends: the status and lives left. */ | |
| 24 | oldEnd: { status: GameState['status']; lives: number } | |
| 25 | newEnd: { status: GameState['status']; lives: number } | |
| 26 | /** The record's rules version differs from today's: the replay may not match the report. */ | |
| 27 | versionMismatch: boolean | |
| 28 | level: number | |
| 29 | } | |
| 30 | ||
| 31 | export interface ReplayOptions { | |
| 32 | /** Turns shown before the autopilot took over. */ | |
| 33 | lead?: number | |
| 34 | /** Turns past the report's last that are still shown. */ | |
| 35 | extra?: number | |
| 36 | } | |
| 37 | ||
| 38 | /** Plays `actions` from `from`, keeping those the rules take while the game is on; the states on the way. */ | |
| 39 | function play(from: GameState, actions: Action[]): { kept: Action[]; states: GameState[] } { | |
| 40 | const kept: Action[] = [] | |
| 41 | const states: GameState[] = [] | |
| 42 | let s = from | |
| 43 | for (const a of actions) { | |
| 44 | if (s.status !== 'playing') break | |
| 45 | try { | |
| 46 | s = step(s, a).state | |
| 47 | } catch { | |
| 48 | break | |
| 49 | } | |
| 50 | kept.push(a) | |
| 51 | states.push(s) | |
| 52 | } | |
| 53 | return { kept, states } | |
| 54 | } | |
| 55 | ||
| 56 | /** Today's autopilot from `from` (answering offers with the first choice), for at most `limit` turns. */ | |
| 57 | function autopilotRun(from: GameState, limit: number): { actions: Action[]; states: GameState[] } { | |
| 58 | const actions: Action[] = [] | |
| 59 | const states: GameState[] = [] | |
| 60 | let s = from | |
| 61 | for (let i = 0; i < limit && s.status === 'playing'; i++) { | |
| 62 | const action: Action | null = s.offer ? { id: 'choose', kind: s.offer[0]! } : s.chargeOffer ? { id: 'sellCharge' } : autopilotPlan(s, predictDanger(s)).action | |
| 63 | if (!action) break | |
| 64 | s = step(s, action).state | |
| 65 | actions.push(action) | |
| 66 | states.push(s) | |
| 67 | } | |
| 68 | return { actions, states } | |
| 69 | } | |
| 70 | ||
| 71 | export function buildReplay(record: RunRecord, options: ReplayOptions = {}): ReplayScript { | |
| 72 | const { lead = 6, extra = 4 } = options | |
| 73 | // The state after each recorded action; `after(-1)` is the start of the run. | |
| 74 | const first = newRun(record.seed, record.startLevel, record.startCharge, record.options) | |
| 75 | const states: GameState[] = [] | |
| 76 | let s = first | |
| 77 | for (const a of record.actions) { | |
| 78 | s = step(s, a).state | |
| 79 | states.push(s) | |
| 80 | } | |
| 81 | const after = (i: number): GameState => (i < 0 ? first : states[i]!) | |
| 82 | const last = after(record.actions.length - 1) | |
| 83 | // The level the report ends in, from the turn that opened it. | |
| 84 | let levelStart = -1 | |
| 85 | for (let i = 0; i < states.length; i++) if (states[i]!.level === last.level) { levelStart = i; break } | |
| 86 | if (levelStart < 0) levelStart = record.actions.length - 1 | |
| 87 | // The autopilot takes over when the last enemy is gone: the first such turn on this level. | |
| 88 | let takeover = record.actions.length - 1 | |
| 89 | for (let i = levelStart; i < states.length; i++) { | |
| 90 | if (states[i]!.level === last.level && states[i]!.enemies.length === 0 && states[i]!.status === 'playing') { takeover = i; break } | |
| 91 | } | |
| 92 | const startIdx = Math.max(levelStart, takeover - lead) | |
| 93 | const start = after(startIdx) | |
| 94 | const prefix = record.actions.slice(startIdx + 1, takeover + 1) | |
| 95 | const fork = after(takeover) | |
| 96 | const recorded = record.actions.slice(takeover + 1) | |
| 97 | const waits: Action[] = Array.from({ length: extra }, () => ({ id: 'wait' })) | |
| 98 | const old = play(fork, [...recorded, ...waits]) | |
| 99 | const neu = autopilotRun(fork, recorded.length + extra) | |
| 100 | const end = (from: GameState, st: GameState[]) => { | |
| 101 | const e = st.at(-1) ?? from | |
| 102 | return { status: e.status, lives: e.lives } | |
| 103 | } | |
| 104 | return { | |
| 105 | start, | |
| 106 | prefix, | |
| 107 | old: old.kept, | |
| 108 | neu: neu.actions, | |
| 109 | oldEnd: end(fork, old.states), | |
| 110 | newEnd: end(fork, neu.states), | |
| 111 | versionMismatch: record.simVersion !== SIM_VERSION, | |
| 112 | level: last.level, | |
| 113 | } | |
| 114 | } |