From 39f763614b48b626eca97c7e695573e980723573 Mon Sep 17 00:00:00 2001
From: Julien Calixte <julien.calixte@theodo.com>
Date: Thu, 28 May 2026 11:47:39 +0200
Subject: [PATCH] feat: add styled QR code generator with logo and edge
 customization

Generates QR codes from a URL with center logo upload, adjustable logo
padding and size, dot/corner-square/corner-dot style pickers, color
controls, and PNG/SVG export. Uses error correction level H so the
logo can occlude up to ~30% of modules without breaking scannability.
---
 src/App.vue                  | 154 ++++++++++++++++++++++
 src/composables/useQrCode.ts |  66 ++++++++++
 src/style.css                | 242 +++++++++++++++++++++++++++++++++++
 3 files changed, 462 insertions(+)
 create mode 100644 src/App.vue
 create mode 100644 src/composables/useQrCode.ts
 create mode 100644 src/style.css

diff --git a/src/App.vue b/src/App.vue
new file mode 100644
index 0000000..2826291
--- /dev/null
+++ b/src/App.vue
@@ -0,0 +1,154 @@
+<script setup lang="ts">
+import { reactive, ref } from 'vue'
+import { useQrCode, type QrOptions } from './composables/useQrCode'
+
+const preview = ref<HTMLDivElement | null>(null)
+
+const options = reactive<QrOptions>({
+  data: 'https://example.com',
+  size: 320,
+  dotsType: 'rounded',
+  dotsColor: '#1f2937',
+  cornersSquareType: 'extra-rounded',
+  cornersSquareColor: '#1f2937',
+  cornersDotType: 'dot',
+  cornersDotColor: '#1f2937',
+  backgroundColor: '#ffffff',
+  image: null,
+  imageMargin: 8,
+  imageSize: 0.4,
+  hideBackgroundDots: true,
+})
+
+const { download } = useQrCode(preview, options)
+
+const dotTypes = ['square', 'dots', 'rounded', 'classy', 'classy-rounded', 'extra-rounded'] as const
+const cornerSquareTypes = ['square', 'dot', 'extra-rounded'] as const
+const cornerDotTypes = ['square', 'dot'] as const
+
+function onLogoChange(e: Event) {
+  const file = (e.target as HTMLInputElement).files?.[0]
+  if (!file) return
+  const reader = new FileReader()
+  reader.onload = () => {
+    options.image = reader.result as string
+  }
+  reader.readAsDataURL(file)
+}
+
+function clearLogo() {
+  options.image = null
+  const input = document.getElementById('logo-input') as HTMLInputElement | null
+  if (input) input.value = ''
+}
+</script>
+
+<template>
+  <div class="app">
+    <header>
+      <h1>QR Code Studio</h1>
+      <p class="subtitle">Generate styled QR codes with logo, dots, and corner customization</p>
+    </header>
+
+    <main>
+      <section class="controls">
+        <div class="field">
+          <label for="url">URL or text</label>
+          <input id="url" v-model="options.data" type="text" placeholder="https://example.com" />
+        </div>
+
+        <fieldset>
+          <legend>Logo</legend>
+          <div class="field">
+            <input id="logo-input" type="file" accept="image/*" @change="onLogoChange" />
+          </div>
+          <div v-if="options.image" class="logo-actions">
+            <img :src="options.image" alt="logo preview" class="logo-thumb" />
+            <button type="button" class="ghost" @click="clearLogo">Remove logo</button>
+          </div>
+          <div class="field">
+            <label>
+              Logo padding
+              <span class="value">{{ options.imageMargin }} px</span>
+            </label>
+            <input v-model.number="options.imageMargin" type="range" min="0" max="40" step="1" />
+          </div>
+          <div class="field">
+            <label>
+              Logo size
+              <span class="value">{{ Math.round(options.imageSize * 100) }} %</span>
+            </label>
+            <input v-model.number="options.imageSize" type="range" min="0.1" max="0.6" step="0.01" />
+          </div>
+          <label class="checkbox">
+            <input v-model="options.hideBackgroundDots" type="checkbox" />
+            Hide dots behind logo
+          </label>
+        </fieldset>
+
+        <fieldset>
+          <legend>Body</legend>
+          <div class="field">
+            <label for="dotsType">Dot style</label>
+            <select id="dotsType" v-model="options.dotsType">
+              <option v-for="t in dotTypes" :key="t" :value="t">{{ t }}</option>
+            </select>
+          </div>
+          <div class="field">
+            <label for="dotsColor">Dot color</label>
+            <input id="dotsColor" v-model="options.dotsColor" type="color" />
+          </div>
+        </fieldset>
+
+        <fieldset>
+          <legend>Corners</legend>
+          <div class="field">
+            <label for="csType">Outer square style</label>
+            <select id="csType" v-model="options.cornersSquareType">
+              <option v-for="t in cornerSquareTypes" :key="t" :value="t">{{ t }}</option>
+            </select>
+          </div>
+          <div class="field">
+            <label for="csColor">Outer square color</label>
+            <input id="csColor" v-model="options.cornersSquareColor" type="color" />
+          </div>
+          <div class="field">
+            <label for="cdType">Inner dot style</label>
+            <select id="cdType" v-model="options.cornersDotType">
+              <option v-for="t in cornerDotTypes" :key="t" :value="t">{{ t }}</option>
+            </select>
+          </div>
+          <div class="field">
+            <label for="cdColor">Inner dot color</label>
+            <input id="cdColor" v-model="options.cornersDotColor" type="color" />
+          </div>
+        </fieldset>
+
+        <fieldset>
+          <legend>Background</legend>
+          <div class="field">
+            <label for="bg">Background color</label>
+            <input id="bg" v-model="options.backgroundColor" type="color" />
+          </div>
+          <div class="field">
+            <label>
+              Size
+              <span class="value">{{ options.size }} px</span>
+            </label>
+            <input v-model.number="options.size" type="range" min="160" max="640" step="20" />
+          </div>
+        </fieldset>
+      </section>
+
+      <section class="preview-pane">
+        <div class="preview-card">
+          <div ref="preview" class="preview"></div>
+        </div>
+        <div class="download">
+          <button type="button" @click="download('png')">Download PNG</button>
+          <button type="button" @click="download('svg')">Download SVG</button>
+        </div>
+      </section>
+    </main>
+  </div>
+</template>
diff --git a/src/composables/useQrCode.ts b/src/composables/useQrCode.ts
new file mode 100644
index 0000000..eb73a05
--- /dev/null
+++ b/src/composables/useQrCode.ts
@@ -0,0 +1,66 @@
+import { onMounted, shallowRef, watch, type Ref } from 'vue'
+import QRCodeStyling, {
+  type DotType,
+  type CornerSquareType,
+  type CornerDotType,
+  type FileExtension,
+} from 'qr-code-styling'
+
+export type QrOptions = {
+  data: string
+  size: number
+  dotsType: DotType
+  dotsColor: string
+  cornersSquareType: CornerSquareType
+  cornersSquareColor: string
+  cornersDotType: CornerDotType
+  cornersDotColor: string
+  backgroundColor: string
+  image: string | null
+  imageMargin: number
+  imageSize: number
+  hideBackgroundDots: boolean
+}
+
+export function useQrCode(container: Ref<HTMLElement | null>, options: QrOptions) {
+  const qr = shallowRef<QRCodeStyling | null>(null)
+
+  onMounted(() => {
+    qr.value = new QRCodeStyling(toLibOptions(options))
+    if (container.value) qr.value.append(container.value)
+  })
+
+  watch(
+    () => ({ ...options }),
+    () => qr.value?.update(toLibOptions(options)),
+    { deep: true },
+  )
+
+  const download = (extension: FileExtension) => {
+    qr.value?.download({ name: 'qrcode', extension })
+  }
+
+  return { download }
+}
+
+function toLibOptions(o: QrOptions) {
+  return {
+    width: o.size,
+    height: o.size,
+    type: 'svg' as const,
+    data: o.data || ' ',
+    image: o.image ?? undefined,
+    margin: 0,
+    qrOptions: { errorCorrectionLevel: 'H' as const },
+    dotsOptions: { color: o.dotsColor, type: o.dotsType },
+    backgroundOptions: { color: o.backgroundColor },
+    cornersSquareOptions: { color: o.cornersSquareColor, type: o.cornersSquareType },
+    cornersDotOptions: { color: o.cornersDotColor, type: o.cornersDotType },
+    imageOptions: {
+      crossOrigin: 'anonymous',
+      margin: o.imageMargin,
+      imageSize: o.imageSize,
+      hideBackgroundDots: o.hideBackgroundDots,
+    },
+  }
+}
diff --git a/src/style.css b/src/style.css
new file mode 100644
index 0000000..2da65b9
--- /dev/null
+++ b/src/style.css
@@ -0,0 +1,242 @@
+:root {
+  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
+  color-scheme: light;
+  color: #0f172a;
+  background: #f1f5f9;
+  -webkit-font-smoothing: antialiased;
+  text-rendering: optimizeLegibility;
+}
+
+* {
+  box-sizing: border-box;
+}
+
+body {
+  margin: 0;
+  min-height: 100vh;
+}
+
+#app {
+  min-height: 100vh;
+}
+
+.app {
+  max-width: 1100px;
+  margin: 0 auto;
+  padding: 32px 24px 64px;
+}
+
+header {
+  margin-bottom: 28px;
+}
+
+h1 {
+  margin: 0 0 6px;
+  font-size: 28px;
+  font-weight: 700;
+  letter-spacing: -0.01em;
+}
+
+.subtitle {
+  margin: 0;
+  color: #64748b;
+  font-size: 15px;
+}
+
+main {
+  display: grid;
+  grid-template-columns: minmax(0, 1fr) minmax(0, 380px);
+  gap: 28px;
+  align-items: start;
+}
+
+@media (max-width: 880px) {
+  main {
+    grid-template-columns: 1fr;
+  }
+}
+
+.controls,
+.preview-card {
+  background: #fff;
+  border: 1px solid #e2e8f0;
+  border-radius: 14px;
+  padding: 20px;
+  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
+}
+
+.controls {
+  display: flex;
+  flex-direction: column;
+  gap: 18px;
+}
+
+fieldset {
+  border: 1px solid #e2e8f0;
+  border-radius: 10px;
+  padding: 14px 16px 16px;
+  margin: 0;
+  display: flex;
+  flex-direction: column;
+  gap: 12px;
+}
+
+legend {
+  padding: 0 6px;
+  font-size: 13px;
+  font-weight: 600;
+  color: #475569;
+  text-transform: uppercase;
+  letter-spacing: 0.06em;
+}
+
+.field {
+  display: flex;
+  flex-direction: column;
+  gap: 6px;
+}
+
+.field label {
+  font-size: 13px;
+  font-weight: 500;
+  color: #334155;
+  display: flex;
+  justify-content: space-between;
+  gap: 8px;
+}
+
+.value {
+  color: #64748b;
+  font-variant-numeric: tabular-nums;
+  font-weight: 400;
+}
+
+input[type="text"],
+select {
+  width: 100%;
+  padding: 9px 11px;
+  border: 1px solid #cbd5e1;
+  border-radius: 8px;
+  font: inherit;
+  background: #fff;
+  transition: border-color 0.12s, box-shadow 0.12s;
+}
+
+input[type="text"]:focus,
+select:focus {
+  outline: none;
+  border-color: #6366f1;
+  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.18);
+}
+
+input[type="color"] {
+  width: 100%;
+  height: 38px;
+  padding: 2px;
+  border: 1px solid #cbd5e1;
+  border-radius: 8px;
+  background: #fff;
+  cursor: pointer;
+}
+
+input[type="range"] {
+  width: 100%;
+  accent-color: #6366f1;
+}
+
+input[type="file"] {
+  font: inherit;
+  font-size: 13px;
+}
+
+.checkbox {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  font-size: 13px;
+  color: #334155;
+  cursor: pointer;
+}
+
+.logo-actions {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+}
+
+.logo-thumb {
+  width: 44px;
+  height: 44px;
+  object-fit: contain;
+  border: 1px solid #e2e8f0;
+  border-radius: 8px;
+  background: #f8fafc;
+  padding: 4px;
+}
+
+.preview-pane {
+  display: flex;
+  flex-direction: column;
+  gap: 14px;
+  position: sticky;
+  top: 24px;
+}
+
+.preview-card {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 24px;
+  min-height: 360px;
+}
+
+.preview {
+  display: flex;
+}
+
+.preview svg,
+.preview canvas {
+  display: block;
+  max-width: 100%;
+  height: auto;
+}
+
+.download {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 10px;
+}
+
+button {
+  font: inherit;
+  font-weight: 600;
+  font-size: 14px;
+  padding: 10px 14px;
+  border-radius: 10px;
+  border: 1px solid transparent;
+  background: #4f46e5;
+  color: #fff;
+  cursor: pointer;
+  transition: background 0.12s, transform 0.05s;
+}
+
+button:hover {
+  background: #4338ca;
+}
+
+button:active {
+  transform: translateY(1px);
+}
+
+button.ghost {
+  background: transparent;
+  color: #475569;
+  border-color: #cbd5e1;
+  padding: 6px 10px;
+  font-size: 13px;
+}
+
+button.ghost:hover {
+  background: #f1f5f9;
+  color: #1e293b;
+}