From c2f94df06df5b15e2295cf71e01716cc9d27ea5a Mon Sep 17 00:00:00 2001
From: Thomas Joise <thomas.joise@tecnostac.com>
Date: Mon, 13 Jul 2026 15:18:43 +0530
Subject: [PATCH] feat(hq): screen paper styles + documentHtmlSample + POST
 /previews/sample

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 apps/hq/src/api.ts                  | 47 ++++++++++++++++--
 apps/hq/src/templates.ts            | 45 ++++++++++++++++-
 apps/hq/test/preview-sample.test.ts | 77 +++++++++++++++++++++++++++++
 3 files changed, 163 insertions(+), 6 deletions(-)
 create mode 100644 apps/hq/test/preview-sample.test.ts

diff --git a/apps/hq/src/api.ts b/apps/hq/src/api.ts
index ccfdcd2..3607225 100644
--- a/apps/hq/src/api.ts
+++ b/apps/hq/src/api.ts
@@ -43,7 +43,7 @@ import {
 } from './repos-aws'
 import { pullMonthlyCosts } from './aws-costs'
 import { clientProfitability, duesAging, moduleRevenue, type DateRange } from './repos-reports'
-import { documentHtml } from './templates'
+import { documentHtml, documentHtmlSample } from './templates'
 import { renderPdf } from './pdf'
 import { emailStatus } from './repos-email'
 import { sendDocumentEmail, type GmailDeps } from './gmail'
@@ -59,6 +59,17 @@ export function apiRouter(db: DB, gmailDeps?: Partial<GmailDeps>): Router {
     ).all() as { key: string; value: string }[]
     return Object.fromEntries(rows.map((row) => [row.key, row.value]))
   }
+  // Shared letterhead field maps — the one definition every route (company profile,
+  // template settings, sample preview) uses to map request field → setting key.
+  const COMPANY_FIELDS: Record<string, string> = {
+    name: 'company.name', address: 'company.address', gstin: 'company.gstin',
+    stateCode: 'company.state_code', phone: 'company.phone', email: 'company.email', bank: 'company.bank',
+  }
+  const TEMPLATE_FIELDS: Record<string, string> = {
+    terms: 'template.terms', declaration: 'template.declaration', jurisdiction: 'template.jurisdiction',
+    footerNote: 'template.footer_note', signatoryLabel: 'template.signatory_label',
+  }
+  const DOC_TYPES = ['QUOTATION', 'PROFORMA', 'INVOICE', 'CREDIT_NOTE', 'RECEIPT'] as const
   // Env read at request time so gmail-connect can run without a restart.
   const gmail = (): GmailDeps => ({
     f: gmailDeps?.f ?? fetch,
@@ -224,6 +235,36 @@ export function apiRouter(db: DB, gmailDeps?: Partial<GmailDeps>): Router {
       res.status(400).json({ ok: false, error: err instanceof Error ? err.message : String(err) })
     }
   })
+  // Sibling preview: sample letterhead / quote-content through the ONE renderer.
+  // Body uses the same field keys as PUT /settings/template (unsaved edits), merged
+  // over the saved settings — so the preview shows exactly what Save would print.
+  r.post('/previews/sample', requireAuth, (req, res) => {
+    const body = req.body as {
+      company?: Record<string, unknown>; template?: Record<string, unknown>
+      titles?: Record<string, unknown>; logo?: unknown; contentLines?: unknown
+    }
+    const merged = companySettings() // company.* + template.*
+    const applyGroup = (group: Record<string, unknown> | undefined, fields: Record<string, string>): void => {
+      if (group === undefined || group === null) return
+      for (const [field, key] of Object.entries(fields)) {
+        const val = group[field]
+        if (typeof val === 'string') merged[key] = val
+      }
+    }
+    applyGroup(body.company, COMPANY_FIELDS)
+    applyGroup(body.template, TEMPLATE_FIELDS)
+    if (body.titles !== undefined && body.titles !== null) {
+      for (const t of DOC_TYPES) {
+        const val = body.titles[t]
+        if (typeof val === 'string') merged[`template.title_${t}`] = val
+      }
+    }
+    if (typeof body.logo === 'string') merged['template.logo'] = body.logo
+    const opts = Array.isArray(body.contentLines)
+      ? { contentLines: body.contentLines.filter((x): x is string => typeof x === 'string') }
+      : {}
+    res.json({ ok: true, html: documentHtmlSample(merged, opts) })
+  })
   r.get('/documents', requireAuth, (req, res) => {
     const filter: DocumentFilter = {}
     if (typeof req.query['type'] === 'string') filter.type = req.query['type']
@@ -580,10 +621,6 @@ export function apiRouter(db: DB, gmailDeps?: Partial<GmailDeps>): Router {
   })
 
   // ---------- company profile (owner-editable; PDFs read these live) ----------
-  const COMPANY_FIELDS: Record<string, string> = {
-    name: 'company.name', address: 'company.address', gstin: 'company.gstin',
-    stateCode: 'company.state_code', phone: 'company.phone', email: 'company.email', bank: 'company.bank',
-  }
   r.get('/settings/company', requireAuth, (_req, res) => {
     res.json({ ok: true, company: companySettings() })
   })
diff --git a/apps/hq/src/templates.ts b/apps/hq/src/templates.ts
index 0f58c76..0206406 100644
--- a/apps/hq/src/templates.ts
+++ b/apps/hq/src/templates.ts
@@ -1,4 +1,4 @@
-import { amountInWordsINR, formatINR, type BillLine, type Paise } from '@sims/domain'
+import { amountInWordsINR, formatINR, type BillLine, type BillTotals, type Paise } from '@sims/domain'
 import type { Client } from './repos-clients'
 import type { Doc, DocType } from './repos-documents'
 
@@ -81,6 +81,10 @@ export function documentHtml(doc: Doc, client: Client, company: Record<string, s
 <title>${esc(doc.docNo ?? 'Draft')}</title>
 <style>
   @page { size: A4; margin: 14mm; }
+  /* On screen (live preview) puppeteer is not involved, so @page margins do not
+     apply — mimic the 14mm print margin and a white page. page.pdf renders the
+     print media, so these screen-only rules never affect the actual PDF. */
+  @media screen { body { padding: 14mm; background: #fff; } }
   * { box-sizing: border-box; }
   body { font-family: 'Segoe UI', Arial, sans-serif; font-size: 11px; color: #1a1a1a; margin: 0; }
   .letterhead { border-bottom: 2px solid #1a1a1a; padding-bottom: 8px; }
@@ -200,6 +204,10 @@ function receiptHtml(doc: Doc, client: Client, company: Record<string, string>):
 <title>${esc(doc.docNo ?? 'Receipt')}</title>
 <style>
   @page { size: A4; margin: 14mm; }
+  /* On screen (live preview) puppeteer is not involved, so @page margins do not
+     apply — mimic the 14mm print margin and a white page. page.pdf renders the
+     print media, so these screen-only rules never affect the actual PDF. */
+  @media screen { body { padding: 14mm; background: #fff; } }
   * { box-sizing: border-box; }
   body { font-family: 'Segoe UI', Arial, sans-serif; font-size: 11px; color: #1a1a1a; margin: 0; }
   .letterhead { border-bottom: 2px solid #1a1a1a; padding-bottom: 8px; }
@@ -256,3 +264,38 @@ function receiptHtml(doc: Doc, client: Client, company: Record<string, string>):
 </body>
 </html>`
 }
+
+/**
+ * Canned sample doc for previewing letterhead + quote-content edits (design §4).
+ * Reuses documentHtml — no second renderer — so what the owner sees is exactly
+ * how a real bill prints. A TAX INVOICE so the header, GSTIN and bank box all
+ * render; the state code follows the company so the split is intra-state.
+ */
+export function documentHtmlSample(company: Record<string, string>, opts: { contentLines?: string[] } = {}): string {
+  const stateCode = company['company.state_code'] ?? '32'
+  const client: Client = {
+    id: 'sample', code: 'SAMPLE', name: 'Sample Client Pvt Ltd', gstin: '32ABCDE1234F1Z5',
+    stateCode, address: '1st Floor, MG Road, Kochi', contacts: [], status: 'active', notes: '',
+  }
+  const line: BillLine = {
+    itemId: 'sample', name: 'POS Billing — Yearly', hsn: '998313', qty: 1, unitCode: 'NOS',
+    unitPricePaise: 10_000_00, grossPaise: 10_000_00, discountPaise: 0, taxablePaise: 10_000_00,
+    taxRateBp: 1800, cgstPaise: 900_00, sgstPaise: 900_00, igstPaise: 0, cessPaise: 0, lineTotalPaise: 11_800_00,
+  }
+  const totals: BillTotals = {
+    grossPaise: 10_000_00, discountPaise: 0, taxablePaise: 10_000_00, cgstPaise: 900_00, sgstPaise: 900_00,
+    igstPaise: 0, cessPaise: 0, roundOffPaise: 0, payablePaise: 11_800_00, savingsVsMrpPaise: 0,
+  }
+  const doc: Doc = {
+    id: 'sample', docType: 'INVOICE', docNo: null, fy: '2026-27', clientId: 'sample',
+    docDate: new Date().toISOString().slice(0, 10), status: 'draft', refDocId: null,
+    taxablePaise: 10_000_00, cgstPaise: 900_00, sgstPaise: 900_00, igstPaise: 0,
+    roundOffPaise: 0, payablePaise: 11_800_00,
+    payload: {
+      lines: [line], totals,
+      lineContents: [opts.contentLines ?? ['Cloud POS billing', 'GST invoicing', 'Priority support']],
+    },
+    source: 'sample', createdBy: 'system', createdAt: '',
+  }
+  return documentHtml(doc, client, company)
+}
diff --git a/apps/hq/test/preview-sample.test.ts b/apps/hq/test/preview-sample.test.ts
new file mode 100644
index 0000000..b633f78
--- /dev/null
+++ b/apps/hq/test/preview-sample.test.ts
@@ -0,0 +1,77 @@
+// apps/hq/test/preview-sample.test.ts
+import { describe, it, expect, afterAll } from 'vitest'
+import express from 'express'
+import { openDb } from '../src/db'
+import { seedIfEmpty } from '../src/seed'
+import { createStaff } from '../src/auth'
+import { documentHtml, documentHtmlSample } from '../src/templates'
+import { apiRouter } from '../src/api'
+
+const sampleDoc = {
+  id: 'd1', docType: 'INVOICE', docNo: 'INV/26-27-0001', fy: '2026-27', clientId: 'c1',
+  docDate: '2026-07-13', status: 'draft', refDocId: null, taxablePaise: 10_000_00,
+  cgstPaise: 900_00, sgstPaise: 900_00, igstPaise: 0, roundOffPaise: 0, payablePaise: 11_800_00,
+  payload: { lines: [], totals: {} },
+} as never
+const sampleClient = { id: 'c1', code: 'X', name: 'X', stateCode: '32', address: '', contacts: [], status: 'active', notes: '' } as never
+
+describe('templates: screen paper styles + documentHtmlSample', () => {
+  it('documentHtml carries screen-only paper styles (PDF unaffected — print media)', () => {
+    expect(documentHtml(sampleDoc, sampleClient, { 'company.name': 'Tecnostac' })).toContain('@media screen')
+  })
+  it('documentHtmlSample renders letterhead, bank box and given bullets through the one renderer', () => {
+    const html = documentHtmlSample(
+      { 'company.name': 'Acme HQ', 'company.bank': 'HDFC ****9', 'company.state_code': '32' },
+      { contentLines: ['Cloud POS', 'GST filing'] },
+    )
+    expect(html).toContain('Acme HQ')
+    expect(html).toContain('HDFC ****9')  // bank box shows (sample is a TAX INVOICE)
+    expect(html).toContain('Cloud POS')
+    expect(html).toContain('GST filing')
+  })
+})
+
+function appWith() {
+  const db = openDb(':memory:'); seedIfEmpty(db)
+  createStaff(db, { email: 'owner@test.in', displayName: 'Owner', role: 'owner', password: 'owner-password' })
+  const app = express(); app.use(express.json()); app.locals['db'] = db; app.use('/api', apiRouter(db))
+  const server = app.listen(0)
+  const base = `http://localhost:${(server.address() as { port: number }).port}/api`
+  return { server, base }
+}
+
+describe('POST /previews/sample', () => {
+  const { server, base } = appWith()
+  afterAll(() => server.close())
+  const login = async () =>
+    (await (await fetch(`${base}/auth/login`, { method: 'POST', headers: { 'content-type': 'application/json' }, body: JSON.stringify({ email: 'owner@test.in', password: 'owner-password' }) })).json() as any).token
+  const call = async (token: string | null, body: unknown) => {
+    const res = await fetch(`${base}/previews/sample`, { method: 'POST', headers: { 'content-type': 'application/json', ...(token ? { authorization: `Bearer ${token}` } : {}) }, body: JSON.stringify(body) })
+    return { status: res.status, json: await res.json() as any }
+  }
+  it('requires auth', async () => { expect((await call(null, {})).status).toBe(401) })
+  it('renders unsaved company edits (field keys, merged over saved settings)', async () => {
+    const token = await login()
+    const r = await call(token, { company: { name: 'Edited Co', bank: 'ICICI ****7' } })
+    expect(r.status).toBe(200)
+    expect(r.json.html).toContain('Edited Co')
+    expect(r.json.html).toContain('ICICI ****7')
+  })
+  it('renders unsaved template.* edits, per-type title, and a picked logo', async () => {
+    const token = await login()
+    const r = await call(token, {
+      template: { footerNote: 'Live footer note', declaration: 'Live declaration' },
+      titles: { INVOICE: 'GST INVOICE' },
+      logo: 'data:image/png;base64,LIVELOGO',
+    })
+    expect(r.json.html).toContain('Live footer note')
+    expect(r.json.html).toContain('Live declaration')
+    expect(r.json.html).toContain('GST INVOICE')
+    expect(r.json.html).toContain('data:image/png;base64,LIVELOGO')
+  })
+  it('renders unsaved quote-content bullets', async () => {
+    const token = await login()
+    const r = await call(token, { contentLines: ['Only this bullet'] })
+    expect(r.json.html).toContain('Only this bullet')
+  })
+})