interiorscan/.specify/specs/001-interiorscan-mvp/plan.md

InteriorScan MVP — Implementation Plan

For Hermes: Use subagent-driven-development skill to implement this plan task-by-task.

Goal: Build an interior photogrammetry SaaS that turns apartment photos into navigable 3D walkthroughs (Doom-map style).

Architecture: Turborepo monorepo (tpl-next-saas template). Next.js 16 App Router for web UI + dashboard. GPU worker (Node.js) orchestrates COLMAP/OpenMVS processing pipeline. three.js FPS viewer for walkthrough navigation. PostgreSQL + Drizzle for data. Valkey for queues/sessions. Stripe for billing.

Tech Stack: Next.js 16 · Drizzle ORM · PostgreSQL · Valkey · three.js · COLMAP · OpenMVS · Stripe · Biome · Vitest

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Constitution Check

Principle	Status	Notes
I. Self-Hosted First	✅ PASS	All infra self-hosted except Stripe
II. Progressive Experience	✅ PASS	WebGL → 360° fallback, mobile tap-to-walk
III. FPS-Grade Immersion	✅ PASS	WASD + mouse primary, tap-to-walk secondary
IV. Photo-First Capture	✅ PASS	Mobile photos as baseline, LiDAR enhancement
V. API-First Architecture	✅ PASS	API endpoints defined before UI
VI. TypeScript Strict	✅ PASS	strict + noUncheckedIndexedAccess
VII. Test-First	⚠ CONDITIONAL	TDD for business logic; 3D viewer tested via Playwright E2E
VIII. Open Formats	✅ PASS	OBJ export in MVP, E57/DXF/IFC in P4+

⚠ VII conditional: 3D rendering correctness is validated via E2E visual regression, not unit tests. Business logic (upload, processing, auth) follows strict TDD.

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Data Model

See data-model.md (separate document — same directory).

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Phase 1: Monorepo Scaffold + Core Infra (Shared)

• T001 Create monorepo from tpl-next-saas template
• T002 Configure Drizzle schema with InteriorScan tables (projects, photos, walkthroughs, processing_jobs, users, teams, subscriptions)
• T003 Run migration: pnpm db:migrate
• T004 [P] Add seed data: 1 user, 1 team, 3 project statuses
• T005 [P] Set up Valkey connection for job queue
• T006 [P] Configure Docker Compose (postgres + valkey + web)

Checkpoint: Migration green, pnpm dev starts without errors, health endpoint returns 200.

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Phase 2: Photo Upload & Processing Pipeline (P1) 🎯 MVP Core

2A: Upload API

• T007 Write failing test: POST /api/v1/projects with photos returns 201 + project ID
• T008 Implement project creation endpoint with Zod validation
• T009 Write failing test: Upload 3 JPEGs → stored in object storage, DB has photo records
• T010 Implement photo upload with deduplication (perceptual hash)
• T011 Write failing test: GET /api/v1/projects/:id returns status + progress
• T012 Implement project status endpoint

Checkpoint: Upload 40 photos via API → receive project ID → poll status → see "queued".

2B: Processing Worker

• T013 Set up apps/processor/ — Node.js worker with BullMQ/Valkey job queue
• T014 Write failing test: Job queued → worker picks up → runs COLMAP SfM → produces sparse point cloud
• T015 Implement COLMAP SfM step (feature extraction + matching + sparse reconstruction)
• T016 Write failing test: SfM output → OpenMVS dense reconstruction → mesh file produced
• T017 Implement OpenMVS dense reconstruction step (MVS + meshing + texturing)
• T018 Write failing test: Mesh + textures → tiled output for three.js streaming
• T019 Implement mesh processing + tiling step (LOD generation, Draco compression, texture atlas)
• T020 Implement progress reporting (Valkey pub/sub → web UI)
• T021 Write failing test: Processing failure → job marked failed → user notified
• T022 Implement error handling + retry logic

Checkpoint: Upload 40 photos → processing completes → produces OBJ mesh + tiled three.js output. Total time <60 min for 100 photos on GPU.

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Phase 3: 3D Viewer — FPS Walkthrough (P1) 🎯 MVP Core

• T023 Create packages/viewer/ — three.js + Vite library package
• T024 Implement FPS camera controller (WASD + mouse look, collision detection, gravity)
• T025 Implement tap-to-walk controller (mobile: tap destination → navmesh pathfinding)
• T026 Implement mesh loader (tiled LODeD mesh streaming, Draco decompression)
• T027 Implement texture loading (progressive: low-res first, high-res on demand)
• T028 Implement mini-map overlay (bird's eye view with player position)
• T029 Implement measurement overlay toggle (room dimensions on walls/floor)
• T030 Implement WebGL fallback detection → 360° photo carousel mode
• T031 Implement touch controls (gyroscope look, pinch-zoom, two-finger walk)
• T032 Write Playwright E2E test: load walkthrough → verify 3D renders → verify WASD movement → verify tap-to-walk

Checkpoint: Open walkthrough link → walk through reconstructed space at 30+ FPS. WASD works. Click-to-walk works. Mini-map shows position.

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Phase 4: Web UI — Dashboard & Sharing (P1 + P2)

• T033 Create project creation flow (multi-step: name/address → photo upload → processing)
• T034 Create processing status page (progress bar, ETA, stage indicator)
• T035 Create walkthrough view page (embedded viewer + share controls)
• T036 Implement share link generation (public, no auth required)
• T037 Implement oEmbed embed code generator
• T038 Create dashboard grid (project cards with thumbnail, status, date)
• T039 Create project settings (edit name, address, delete)

Checkpoint: Agent creates project → uploads photos → sees processing progress → walkthrough appears → shares link → visitor navigates without login.

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Phase 5: Auth, Teams & Billing (P3)

• T040 Set up better-auth with email + Google OAuth
• T041 Implement RBAC (owner/admin/member/viewer per team)
• T042 Create subscription tiers (Free: 3/month, Pro: 25/month, Enterprise: unlimited)
• T043 Implement Stripe checkout + webhook
• T044 Implement usage tracking + quota enforcement middleware

Checkpoint: User signs up → creates 3 projects on Free → gets upgrade prompt → pays via Stripe → quota increases.

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Phase 6: Polish & Launch

• T045 Landing page with demo walkthrough embedded
• T046 Pricing page with 3 tiers
• T047 Email notifications (processing complete, processing failed, quota warning)
• T048 Mobile-responsive dashboard with bottom nav
• T049 Accessibility audit (WCAG 2.2 AA): keyboard nav, screen reader, contrast
• T050 Performance audit (Core Web Vitals, first mesh load <5s on 4G)

Checkpoint: Real tester (monyi's friends) create walkthrough from phone photos in <1h total. Lighthouse 90+.