docs(06-04): complete signature modal + submission plan — SUMMARY, STATE, ROADMAP updated

- SignatureModal with Draw/Type/Use Saved tabs (signature_pad DPR scaling)
- POST /api/sign/[token] atomic one-time claim, PDF embed, SHA-256 hash, audit trail
- SIGN-04, SIGN-05, LEGAL-01, LEGAL-02 requirements complete

.planning/REQUIREMENTS.md

@@ -45,8 +45,8 @@
 - [x] **SIGN-01**: Client receives an email with a unique link to sign the document (no account required)
 - [x] **SIGN-02**: Signing link expires after 72 hours and can only be used once
 - [x] **SIGN-03**: Client opens the link in any browser and sees the prepared PDF with signature fields highlighted
-- [ ] **SIGN-04**: Client can draw a freehand signature on a canvas (works on mobile and desktop)
+- [x] **SIGN-04**: Client can draw a freehand signature on a canvas (works on mobile and desktop)
-- [ ] **SIGN-05**: Client can save a default signature and click a signature field to apply it without redrawing
+- [x] **SIGN-05**: Client can save a default signature and click a signature field to apply it without redrawing
 - [ ] **SIGN-06**: Client sees a confirmation screen after successfully signing
 - [ ] **SIGN-07**: Agent can download the signed PDF from the dashboard
 
@@ -128,8 +128,8 @@ Which phases cover which requirements. Updated during roadmap creation.
 | SIGN-01 | Phase 6 | Complete |
 | SIGN-02 | Phase 6 | Complete |
 | SIGN-03 | Phase 6 | Complete |
-| SIGN-04 | Phase 6 | Pending |
+| SIGN-04 | Phase 6 | Complete |
-| SIGN-05 | Phase 6 | Pending |
+| SIGN-05 | Phase 6 | Complete |
 | SIGN-06 | Phase 6 | Pending |
 | LEGAL-01 | Phase 6 | Complete |
 | LEGAL-02 | Phase 6 | Complete |

.planning/ROADMAP.md

@@ -153,5 +153,5 @@ Phases execute in numeric order: 1 → 2 → 3 → 4 → 5 → 6 → 7
 | 3. Agent Portal Shell | 4/4 | Complete   | 2026-03-19 |
 | 4. PDF Ingest | 4/4 | Complete   | 2026-03-20 |
 | 5. PDF Fill and Field Mapping | 3/4 | In Progress|  |
-| 6. Signing Flow | 3/6 | In Progress|  |
+| 6. Signing Flow | 4/6 | In Progress|  |
 | 7. Audit Trail and Download | 0/? | Not started | - |

.planning/STATE.md

@@ -3,12 +3,12 @@ gsd_state_version: 1.0
 milestone: v1.0
 milestone_name: milestone
 status: unknown
-last_updated: "2026-03-20T17:32:09.418Z"
+last_updated: "2026-03-20T17:41:00Z"
 progress:
   total_phases: 6
   completed_phases: 5
   total_plans: 24
-  completed_plans: 21
+  completed_plans: 22
 ---
 
 # Project State
@@ -22,12 +22,12 @@ See: .planning/PROJECT.md (updated 2026-03-19)
 
 ## Current Position
 
-Phase: 6 of 7 (Signing Flow) — Plan 3 complete
+Phase: 6 of 7 (Signing Flow) — Plan 4 complete
-Plan: 06-03 (3 of 5 plans) — public signing page, PDF viewer, field overlays, audit route
+Plan: 06-04 (4 of 5 plans) — SignatureModal, atomic POST submission, SHA-256 hash, audit trail
-Status: /sign/[token] public route with server-side token validation (expired/used/pending states), react-pdf full-scroll PDF viewer with pulsing blue field overlays, sticky progress bar, GET /api/sign/[token] audit route, GET /api/sign/[token]/pdf streaming route — npm run build passes cleanly.
+Status: SignatureModal with Draw/Type/Use Saved tabs (signature_pad + DPR scaling), POST /api/sign/[token] with atomic one-time-use claim, embedSignatureInPdf, pdfHash stored, document status=Signed, full LEGAL-01 audit trail, /sign/[token]/confirmed page — npm run build passes cleanly.
-Last activity: 2026-03-20 — Phase 6 Plan 03: signing page (server component + PDF viewer + progress bar)
+Last activity: 2026-03-20 — Phase 6 Plan 04: signature modal + submission route
 
-Progress: [████████░░] 87%
+Progress: [█████████░] 91%
 
 ## Performance Metrics
 
@@ -61,6 +61,7 @@ Progress: [████████░░] 87%
 | Phase 06-signing-flow P01 | 2 | 2 tasks | 8 files |
 | Phase 06-signing-flow P02 | 2 | 2 tasks | 4 files |
 | Phase 06-signing-flow P03 | 3 | 2 tasks | 6 files |
+| Phase 06-signing-flow P04 | 7 | 2 tasks | 4 files |
 
 ## Accumulated Context
 
@@ -128,6 +129,10 @@ Recent decisions affecting current work:
 - [Phase 06-signing-flow]: Status update in send/route.ts guarded by status=Draft — prevents downgrading Sent/Signed documents
 - [Phase 06-signing-flow]: SigningPageClientWrapper uses dynamic import (ssr:false) — react-pdf requires browser APIs that cannot run server-side
 - [Phase 06-signing-flow]: PDF served via /api/sign/[token]/pdf (token-authenticated) not /api/documents/[id]/file (agent-authenticated) — signing page is public
+- [Phase 06-signing-flow 06-04]: signedFields changed from Set<string> to Map<string,string> (fieldId->dataURL) to support signature preview image in signed overlays
+- [Phase 06-signing-flow 06-04]: POST /api/sign/[token] atomic claim via Drizzle UPDATE...WHERE isNull(usedAt).returning() — 0 rows = 409, PDF never written on race condition
+- [Phase 06-signing-flow 06-04]: /sign/[token]/confirmed is static server component — token already used at this point, no re-validation needed
+- [Phase 06-signing-flow 06-04]: sendAgentNotificationEmail is fire-and-forget via .then().catch() — email failure must never prevent the signing confirmation from reaching the client
 
 ### Pending Todos
 
@@ -144,5 +149,5 @@ None yet.
 ## Session Continuity
 
 Last session: 2026-03-20
-Stopped at: Completed 06-03-PLAN.md — signing page, PDF viewer, field overlays, progress bar, audit route
+Stopped at: Completed 06-04-PLAN.md — SignatureModal, POST submission route, confirmed page
 Resume file: None

.planning/phases/06-signing-flow/06-04-SUMMARY.md

@@ -0,0 +1,152 @@
+---
+phase: 06-signing-flow
+plan: "04"
+subsystem: ui+api
+tags: [signature-modal, signature_pad, mobile-canvas, draw-type-saved, atomic-submission, pdf-embed, sha256, audit-trail, one-time-enforcement]
+
+# Dependency graph
+requires:
+  - phase: 06-signing-flow/06-01
+    provides: embedSignatureInPdf(), logAuditEvent(), signingTokens table, verifySigningToken()
+  - phase: 06-signing-flow/06-02
+    provides: sendAgentNotificationEmail()
+  - phase: 06-signing-flow/06-03
+    provides: SigningPageClient.tsx with onFieldClick stub, signaturesRef, signedFields state
+
+provides:
+  - SignatureModal: Draw/Type/Use Saved tabs with signature_pad (devicePixelRatio scaling, touch-none)
+  - SigningPageClient wired to modal: field click opens modal, confirmed field shows preview image
+  - POST /api/sign/[token]: atomic one-time claim, PDF embedding, SHA-256 hash, full audit trail
+  - /sign/[token]/confirmed: success page for post-submission redirect
+
+affects: [06-05]
+
+# Tech tracking
+tech-stack:
+  added: []
+  patterns:
+    - signature_pad initialized with devicePixelRatio scaling — canvas.width/height = offsetWidth/Height * ratio; ctx.scale(ratio, ratio) before mounting SignaturePad
+    - Typed signature rendered via offscreen canvas (document.createElement('canvas')) in Dancing Script 700 at 44px
+    - Use Saved tab conditioned on localStorage key 'teressa_homes_saved_signature' — only appears if saved sig exists
+    - Atomic one-time token claim via Drizzle UPDATE...WHERE isNull(usedAt).returning() — 0 rows returned = 409, no PDF written
+    - Coordinates for PDF embedding always from DB signatureFields, never from request body
+    - Fire-and-forget email via .then().catch() — sendAgentNotificationEmail failure does not fail the signing response
+    - /sign/[token]/confirmed is a static server component — no token re-validation (submission already committed)
+
+key-files:
+  created:
+    - teressa-copeland-homes/src/app/sign/[token]/_components/SignatureModal.tsx
+    - teressa-copeland-homes/src/app/sign/[token]/confirmed/page.tsx
+  modified:
+    - teressa-copeland-homes/src/app/sign/[token]/_components/SigningPageClient.tsx
+    - teressa-copeland-homes/src/app/api/sign/[token]/route.ts
+
+key-decisions:
+  - "signedFields changed from Set<string> to Map<string,string> (fieldId->dataURL) to support preview image rendering in field overlays"
+  - "handleSubmit in SigningPageClient POSTs to /api/sign/[token] and navigates to /sign/[token]/confirmed on 200 or 409"
+  - "Confirmed page is static (no token validation) — the submission already committed the token as used; re-validating would return 'used' state"
+  - "Agent notification email uses fire-and-forget pattern — email failure must never prevent the signing confirmation from reaching the client"
+  - "void save pattern in handleModalConfirm — save flag acknowledged but localStorage write happens inside SignatureModal before onConfirm fires"
+
+requirements-completed: [SIGN-04, SIGN-05, LEGAL-01, LEGAL-02]
+
+# Metrics
+duration: 7min
+completed: 2026-03-20
+---
+
+# Phase 6 Plan 04: Signature Modal + Submission Route Summary
+
+**SignatureModal with Draw/Type/Use Saved tabs (signature_pad + devicePixelRatio), POST /api/sign/[token] with atomic one-time-use enforcement, SHA-256 PDF hash, and full LEGAL-01/LEGAL-02 audit trail**
+
+## Performance
+
+- **Duration:** 7 min
+- **Started:** 2026-03-20T17:33:56Z
+- **Completed:** 2026-03-20T17:40:56Z
+- **Tasks:** 2
+- **Files modified:** 4
+
+## Accomplishments
+
+- SignatureModal.tsx: Draw tab with signature_pad (devicePixelRatio scaling + touch-action:none for mobile), Type tab with Dancing Script cursive preview, Use Saved tab conditionally shown from localStorage
+- Save for later checkbox persists drawn/typed signature to localStorage under `teressa_homes_saved_signature` key
+- SigningPageClient.tsx: modal wired to field click, signedFields Map tracks fieldId->dataURL, signed overlays show preview image
+- POST /api/sign/[token]: atomic UPDATE...WHERE usedAt IS NULL RETURNING — 0 rows = 409, PDF never written on race condition
+- embedSignatureInPdf called with server-side field coordinates (never client-supplied x/y)
+- pdfHash (SHA-256) and signedFilePath stored in documents table; document status updated to Signed
+- signature_submitted and pdf_hash_computed audit events logged (completing LEGAL-01 full 6-event audit trail)
+- Fire-and-forget sendAgentNotificationEmail — email failure never fails the signing response
+- /sign/[token]/confirmed success page created for post-submission redirect
+- npm run build passes cleanly; /sign/[token]/confirmed visible in route manifest
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: SignatureModal + SigningPageClient wiring** - `05b5207` (feat)
+2. **Task 2: POST /api/sign/[token] + confirmed page** - `d445c28` (feat)
+
+**Plan metadata:** (docs commit — see below)
+
+## Files Created/Modified
+
+- `teressa-copeland-homes/src/app/sign/[token]/_components/SignatureModal.tsx` - Draw/Type/Use Saved modal; signature_pad with DPR scaling; Dancing Script typed rendering; localStorage save/load
+- `teressa-copeland-homes/src/app/sign/[token]/_components/SigningPageClient.tsx` - Updated: modal state, signedFields Map, handleModalConfirm, handleSubmit POST, field preview images
+- `teressa-copeland-homes/src/app/api/sign/[token]/route.ts` - Added POST handler: atomic token claim, audit events, PDF embed, hash storage, document status update, agent notification
+- `teressa-copeland-homes/src/app/sign/[token]/confirmed/page.tsx` - Static success page: branded header, green checkmark, "Document Signed" message
+
+## Decisions Made
+
+- `signedFields` type changed from `Set<string>` to `Map<string, string>` (fieldId -> dataURL) — needed to render the signature preview image inside each signed overlay.
+- `handleSubmit` wired directly in `SigningPageClient` (not as a prop from the server component) — the token is already available as a prop; no need to thread a submit handler through the component tree.
+- `/sign/[token]/confirmed` is a static server component with no token validation — re-validation at this point would return `used` state (because the POST already set `usedAt`). The user has already confirmed submission.
+- `sendAgentNotificationEmail` is fire-and-forget via `.then().catch()` to avoid blocking the signing response on email delivery.
+- `clientName` for the agent email falls back to `doc.name` — the `sendAgentNotificationEmail` signature expects clientName; we use document name as a reasonable fallback when client lookup isn't worth an extra join.
+
+## Deviations from Plan
+
+### Auto-fixed Issues
+
+**1. [Rule 2 - Missing Critical] Created /sign/[token]/confirmed page**
+- **Found during:** Task 2 (POST handler)
+- **Issue:** The POST handler returns `{ ok: true }` and the client-side `handleSubmit` navigates to `/sign/${token}/confirmed`. Without this page, the redirect would land on a Next.js 404. The plan specified the redirect behavior but did not include a confirmed page task.
+- **Fix:** Created a static server component at `/sign/[token]/confirmed/page.tsx` with a branded success UI.
+- **Files modified:** `teressa-copeland-homes/src/app/sign/[token]/confirmed/page.tsx` (new)
+- **Commit:** `d445c28` (Task 2 commit)
+
+---
+
+**Total deviations:** 1 auto-fixed (Rule 2 — missing critical confirmed landing page)
+**Impact on plan:** Necessary for correctness — the POST redirect would 404 without it. Simple static page, no scope creep.
+
+## Issues Encountered
+
+None.
+
+## User Setup Required
+
+None — no external service configuration required for this plan.
+
+## Next Phase Readiness
+
+Phase 6 Plan 04 completes the core signing capture and submission loop:
+- Clients can draw, type, or reuse a saved signature for each field
+- Submitting POSTs all captured signatures; the server atomically claims the token, embeds all signatures at server-stored coordinates, records SHA-256 hash, updates document status to Signed
+- Full LEGAL-01 audit trail (6 events: document_prepared, email_sent, link_opened, document_viewed, signature_submitted, pdf_hash_computed) is now complete
+- LEGAL-02 SHA-256 hash stored in documents.pdfHash
+- Plan 05 can read signedFilePath to allow the agent to download the signed PDF from the portal
+
+---
+*Phase: 06-signing-flow*
+*Completed: 2026-03-20*
+
+## Self-Check: PASSED
+
+- FOUND: `teressa-copeland-homes/src/app/sign/[token]/_components/SignatureModal.tsx`
+- FOUND: `teressa-copeland-homes/src/app/sign/[token]/_components/SigningPageClient.tsx`
+- FOUND: `teressa-copeland-homes/src/app/api/sign/[token]/route.ts`
+- FOUND: `teressa-copeland-homes/src/app/sign/[token]/confirmed/page.tsx`
+- FOUND: `.planning/phases/06-signing-flow/06-04-SUMMARY.md`
+- Commit `05b5207` verified in git log
+- Commit `d445c28` verified in git log