3.9 KiB
Implementation Plan: Turn Navigation
Branch: 012-turn-navigation | Date: 2026-03-05 | Spec: spec.md
Input: Feature specification from /specs/012-turn-navigation/spec.md
Summary
Add a RetreatTurn domain operation (inverse of AdvanceTurn) and relocate both Previous/Next Turn buttons to a new turn navigation bar at the top of the encounter tracker. The domain function is a pure state transition that decrements the active index (wrapping to the last combatant and decrementing round number when crossing a round boundary), with a guard preventing retreat before the encounter start (round 1, index 0).
Technical Context
Language/Version: TypeScript 5.8 (strict mode, verbatimModuleSyntax) Primary Dependencies: React 19, Vite 6, Tailwind CSS v4, shadcn/ui-style components, Lucide React (icons) Storage: N/A (no storage changes -- existing localStorage persistence unchanged) Testing: Vitest (pure-function domain tests + component tests) Target Platform: Web browser (single-user, local-first) Project Type: Web application (monorepo: domain + application + web adapter) Performance Goals: Standard web app -- instant UI response (<100ms) Constraints: Domain layer must remain pure (no I/O, no framework imports) Scale/Scope: Single-user encounter tracker, ~5-20 combatants typical
Constitution Check
GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.
| Principle | Status | Notes |
|---|---|---|
| I. Deterministic Domain Core | PASS | RetreatTurn is a pure function: same input = same output. No I/O, randomness, or clocks. |
| II. Layered Architecture | PASS | Domain (retreat-turn.ts) -> Application (retreat-turn-use-case.ts) -> Adapter (React hook + component). Dependency direction preserved. |
| III. Agent Boundary | N/A | No agent layer involved. |
| IV. Clarification-First | PASS | No ambiguities remain in spec. All edge cases resolved. |
| V. Escalation Gates | PASS | Implementation matches spec scope exactly. |
| VI. MVP Baseline Language | PASS | Assumptions use "MVP baseline does not include" phrasing. |
| VII. No Gameplay Rules | PASS | No gameplay mechanics in plan. |
Project Structure
Documentation (this feature)
specs/012-turn-navigation/
├── plan.md # This file
├── research.md # Phase 0 output
├── data-model.md # Phase 1 output
├── quickstart.md # Phase 1 output
├── contracts/ # Phase 1 output
└── tasks.md # Phase 2 output (via /speckit.tasks)
Source Code (repository root)
packages/domain/src/
├── retreat-turn.ts # NEW: RetreatTurn pure function
├── events.ts # MODIFY: Add TurnRetreated + RoundRetreated events
├── types.ts # UNCHANGED
├── index.ts # MODIFY: Re-export retreatTurn
└── __tests__/
└── retreat-turn.test.ts # NEW: All acceptance scenarios
packages/application/src/
├── retreat-turn-use-case.ts # NEW: Orchestrates retreatTurn via EncounterStore
├── ports.ts # UNCHANGED
├── index.ts # MODIFY: Re-export new use case
└── ...
apps/web/src/
├── components/
│ ├── turn-navigation.tsx # NEW: Top-placed Previous/Next turn bar
│ └── action-bar.tsx # MODIFY: Remove Next Turn button
├── hooks/
│ └── use-encounter.ts # MODIFY: Add retreatTurn handler
└── App.tsx # MODIFY: Add TurnNavigation component above combatant list
Structure Decision: Follows existing monorepo layout (domain -> application -> web adapter). New files mirror the existing advance-turn pattern. The turn navigation component is a new UI component placed in the existing components directory.