Add SVG/PNG/draw.io export for rack concepts, center the add-device hint

- Extract the elevation's <svg> body into inc/elevation_svg_content.html,
  shared by the on-page elevation and a new standalone export template
  so they never drift apart.
- Add "Export" dropdown above the elevation: Front/Rear as standalone
  SVG (self-contained inline styles, no dependency on the page's CSS,
  absolute device-type image URLs so the file still works once saved
  elsewhere), Front/Rear as PNG (rasterized entirely client-side via
  <canvas> from that same SVG - no new server-side image dependency),
  and the whole concept as a draw.io (.drawio / mxGraph XML) diagram
  with both faces side by side, reusing the identical block geometry.
- Center the "+ Add device" hint on empty units instead of
  right-aligning it.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

README.md

@@ -44,6 +44,11 @@ Dazu:
   unverkabelten Komponente wird sie mit einem Concept Cable verbunden. Ein „Add
   Components"-Dropdown (genau wie am echten Gerät) legt neue Komponenten pro Typ an —
   nötig für Platzhalter ohne Gerätetyp, die nichts zum Syncen haben.
+* **Export** – Button **„Export"** über der Elevation: Front bzw. Rear jeweils als
+  eigenständige **SVG**- oder **PNG**-Datei, sowie das ganze Konzept (beide Seiten) als
+  **Draw.io**-Diagramm (`.drawio`, per Datei > Öffnen oder Extras > Diagramm bearbeiten
+  in diagrams.net einlesbar). PNG wird komplett im Browser aus dem SVG gerastert —
+  dafür ist keine zusätzliche Bildbibliothek auf dem Server nötig.
 * Vollständige REST-API, Filter, CSV-Import/-Export, Bulk-Edit, Changelog, Journal,
   Tags, Custom Fields und globale Suche — wie bei jedem Core-Objekt.
 

netbox_rack_concept/drawio.py

@@ -0,0 +1,112 @@
+"""
+Export a rack concept as a draw.io (diagrams.net) diagram.
+
+Reuses the same Elevation/ElevationBlock geometry the on-page SVG and the SVG export
+are built from, so all three always agree on where everything sits. The output is a
+plain mxGraph XML file - drawio can open it directly (File > Open) or import it
+(Extras > Edit Diagram accepts the same XML pasted in).
+"""
+import html as html_lib
+
+from .elevation import get_elevations
+
+__all__ = ('build_drawio',)
+
+LABEL_HEIGHT = 30
+FACE_GAP = 60
+
+
+def _escape(text):
+    """HTML-escape for use inside an html=1 cell value (which is itself XML-escaped
+    again by the caller) - two layers, same as any HTML embedded in an XML attribute."""
+    return html_lib.escape(text or '', quote=False)
+
+
+def _quote_attr(value):
+    """XML-attribute-escape a string, matching xml.sax.saxutils.quoteattr but always
+    using double quotes so it's safe to splice straight into our hand-built XML."""
+    return '"' + (
+        value.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;').replace('"', '&quot;')
+    ) + '"'
+
+
+class _CellBuilder:
+    """Accumulates mxCell XML fragments and hands out fresh ids."""
+
+    def __init__(self):
+        self._next_id = 1
+        self.cells = []
+
+    def _id(self):
+        self._next_id += 1
+        return f'c{self._next_id}'
+
+    def add(self, value, style, x, y, width, height):
+        cell_id = self._id()
+        self.cells.append(
+            f'        <mxCell id="{cell_id}" value={_quote_attr(value)} style={_quote_attr(style)} '
+            f'vertex="1" parent="1">\n'
+            f'          <mxGeometry x="{x:.2f}" y="{y:.2f}" width="{width:.2f}" height="{height:.2f}" '
+            f'as="geometry"/>\n'
+            f'        </mxCell>'
+        )
+        return cell_id
+
+
+def _device_style(block):
+    style = (
+        f'rounded=1;whiteSpace=wrap;html=1;arcSize=8;'
+        f'fillColor=#{block.color};fontColor=#{block.text_color};fontSize=11;'
+    )
+    if block.opposite:
+        style += 'dashed=1;opacity=45;'
+    return style
+
+
+def build_drawio(concept):
+    front, rear = get_elevations(concept)
+    builder = _CellBuilder()
+
+    offset_x = 0.0
+    for elevation in (front, rear):
+        builder.add(
+            _escape(elevation.face_label.title()),
+            'text;html=1;align=center;verticalAlign=middle;fontStyle=1;fontSize=14;',
+            offset_x, 0, elevation.width, LABEL_HEIGHT - 4
+        )
+        builder.add(
+            '', 'rounded=0;whiteSpace=wrap;html=1;fillColor=none;strokeColor=#35404A;strokeWidth=2;',
+            offset_x + elevation.rack_x, LABEL_HEIGHT + 6, elevation.rack_width, elevation.height - 12
+        )
+        for unit in elevation.units:
+            builder.add(
+                str(unit.number),
+                'text;html=1;align=right;verticalAlign=middle;fontSize=10;fontColor=#808F9C;spacingRight=4;',
+                offset_x, LABEL_HEIGHT + unit.y, elevation.rack_x - 4, unit.height
+            )
+        for block in elevation.blocks:
+            label = _escape(block.label)
+            if block.sublabel:
+                label += '<br>' + _escape(block.sublabel)
+            builder.add(
+                label, _device_style(block),
+                offset_x + block.x, LABEL_HEIGHT + block.y, block.width, block.height
+            )
+        offset_x += elevation.width + FACE_GAP
+
+    body = '\n'.join(builder.cells)
+
+    return (
+        '<mxfile host="netbox-rack-concept">\n'
+        f'  <diagram id="concept-{concept.pk}" name={_quote_attr(concept.name)}>\n'
+        '    <mxGraphModel dx="800" dy="600" grid="1" gridSize="10" guides="1" tooltips="1" connect="1" '
+        'arrows="1" fold="1" page="1" pageScale="1" pageWidth="850" pageHeight="1100" math="0" shadow="0">\n'
+        '      <root>\n'
+        '        <mxCell id="0"/>\n'
+        '        <mxCell id="1" parent="0"/>\n'
+        f'{body}\n'
+        '      </root>\n'
+        '    </mxGraphModel>\n'
+        '  </diagram>\n'
+        '</mxfile>\n'
+    )

netbox_rack_concept/elevation.py

@@ -116,6 +116,7 @@ class Elevation:
         self.rack_width = RACK_WIDTH
         self.rack_x = RACK_X
         self.rack_right = RACK_X + RACK_WIDTH
+        self.rack_center_x = RACK_X + RACK_WIDTH / 2
         self.width = RACK_X + RACK_WIDTH + MARGIN
         self.height = concept.u_height * UNIT_HEIGHT + MARGIN * 2
 

netbox_rack_concept/static/netbox_rack_concept/export.js

@@ -0,0 +1,83 @@
+/*
+ * "Export as PNG" - fetches the same standalone SVG the SVG download link points to
+ * and rasterizes it client-side via <canvas>. Deliberately no server-side image
+ * library involved: a NetBox plugin shouldn't need one just for this, and every
+ * browser can already turn an SVG into a PNG on its own.
+ */
+(function () {
+    'use strict';
+
+    const SCALE = 2; // render at 2x so the PNG stays crisp
+
+    document.querySelectorAll('.concept-export-png').forEach(function (link) {
+        link.addEventListener('click', function (event) {
+            event.preventDefault();
+            exportPng(link.dataset.svgUrl, link.dataset.filename || 'export.png');
+        });
+    });
+
+    function exportPng(svgUrl, filename) {
+        fetch(svgUrl, { credentials: 'same-origin' })
+            .then(function (response) {
+                if (!response.ok) {
+                    throw new Error('Could not load the SVG (' + response.status + ').');
+                }
+                return response.text();
+            })
+            .then(function (svgText) {
+                rasterize(svgText, filename);
+            })
+            .catch(function () {
+                window.alert('The PNG could not be generated.');
+            });
+    }
+
+    function rasterize(svgText, filename) {
+        const sizeMatch = svgText.match(/<svg[^>]*\swidth="([\d.]+)"[^>]*\sheight="([\d.]+)"/);
+        const width = sizeMatch ? parseFloat(sizeMatch[1]) : 800;
+        const height = sizeMatch ? parseFloat(sizeMatch[2]) : 600;
+
+        const svgBlob = new Blob([svgText], { type: 'image/svg+xml;charset=utf-8' });
+        const svgUrl = URL.createObjectURL(svgBlob);
+        const img = new Image();
+
+        img.onload = function () {
+            URL.revokeObjectURL(svgUrl);
+
+            const canvas = document.createElement('canvas');
+            canvas.width = width * SCALE;
+            canvas.height = height * SCALE;
+            const ctx = canvas.getContext('2d');
+            // The SVG itself has a white background, but that's inside a <style> block,
+            // which some rasterizers (older WebKit) ignore when drawing to canvas.
+            ctx.fillStyle = '#ffffff';
+            ctx.fillRect(0, 0, canvas.width, canvas.height);
+            ctx.drawImage(img, 0, 0, canvas.width, canvas.height);
+
+            canvas.toBlob(function (blob) {
+                if (!blob) {
+                    window.alert('The PNG could not be generated.');
+                    return;
+                }
+                const downloadUrl = URL.createObjectURL(blob);
+                const link = document.createElement('a');
+                link.href = downloadUrl;
+                link.download = filename;
+                document.body.appendChild(link);
+                link.click();
+                link.remove();
+                URL.revokeObjectURL(downloadUrl);
+            }, 'image/png');
+        };
+
+        img.onerror = function () {
+            URL.revokeObjectURL(svgUrl);
+            // Most likely a device type image from a different origin without
+            // permissive CORS headers, which taints the canvas and blocks toBlob().
+            window.alert('The PNG could not be generated. This can happen when a device '
+                + 'type image is hosted on a different domain without CORS enabled.');
+        };
+
+        img.src = svgUrl;
+    }
+})();

netbox_rack_concept/templates/netbox_rack_concept/elevation_export.html

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
+     width="{{ elevation.width }}" height="{{ elevation.height }}"
+     viewBox="0 0 {{ elevation.width }} {{ elevation.height }}">
+  <title>{{ elevation.concept.name }} - {{ elevation.face_label|title }}</title>
+  <style>
+    /* Concrete colours, not the on-page CSS custom properties: this file is meant to
+       be opened outside NetBox, where those variables don't exist. */
+    svg { background-color: #ffffff; font-family: -apple-system, "Segoe UI", Roboto, Arial, sans-serif; }
+    .unit-slot { fill: #f6f8fa; stroke: #dadfe5; stroke-width: 1; }
+    .unit-label { font-size: 10px; fill: #808f9c; }
+    .rack-frame { stroke: #35404a; stroke-width: 2; }
+    .device-rect { stroke: rgba(0, 0, 0, 0.35); stroke-width: 1; }
+    .device-label { font-size: 11px; }
+    .device-image-label { font-size: 11px; }
+    .device-image-label-stroke { fill: none; stroke: #000000; stroke-width: 0.2em; stroke-linejoin: round; }
+    .device-image-label-fill { fill: #ffffff; }
+    .opposite-hint { font-size: 9px; opacity: 0.8; }
+    .device-block.opposite .device-rect { stroke-dasharray: 3 2; }
+    .add-device-hint { display: none; }
+  </style>
+  {% include 'netbox_rack_concept/inc/elevation_svg_content.html' %}
+</svg>

netbox_rack_concept/templates/netbox_rack_concept/inc/elevation.html

@@ -1,90 +1,10 @@
 {% load i18n %}
-{% load l10n %}
-{% comment %}
-  One face of a concept rack. Localization is switched off below because SVG
-  coordinates must use a dot as the decimal separator whatever the UI language is.
-{% endcomment %}
-{% localize off %}
 <div class="concept-elevation" data-face="{{ elevation.face }}">
   <h5 class="text-center text-muted mb-2">{{ elevation.face_label|title }}</h5>
   <svg width="{{ elevation.width }}" height="{{ elevation.height }}"
        viewBox="0 0 {{ elevation.width }} {{ elevation.height }}"
        class="concept-elevation-svg" role="img"
        aria-label="{% blocktrans with face=elevation.face_label name=elevation.concept.name %}{{ face }} elevation of {{ name }}{% endblocktrans %}">
-
+    {% include 'netbox_rack_concept/inc/elevation_svg_content.html' %}
-    {# Unit rows and legend. An empty unit becomes a click target for adding a device
-       here, exactly like a real rack's elevation. #}
-    {% for unit in elevation.units %}
-      <g class="unit">
-        {% if not unit.occupied and can_add_device %}
-          <a href="{% url 'plugins:netbox_rack_concept:conceptdevice_add' %}?concept={{ elevation.concept.pk }}&amp;position={{ unit.number }}&amp;face={{ elevation.face }}&amp;return_url={{ elevation.concept.get_absolute_url }}">
-            <rect x="{{ elevation.rack_x }}" y="{{ unit.y }}"
-                  width="{{ elevation.rack_width }}" height="{{ unit.height }}"
-                  class="unit-slot free"
-                  data-unit="{{ unit.number }}"></rect>
-            <text x="{{ elevation.rack_right|add:'-6' }}" y="{{ unit.y }}" dy="15"
-                  class="add-device-hint" text-anchor="end">+ {% trans "Add device" %}</text>
-          </a>
-        {% else %}
-          <rect x="{{ elevation.rack_x }}" y="{{ unit.y }}"
-                width="{{ elevation.rack_width }}" height="{{ unit.height }}"
-                class="unit-slot"
-                data-unit="{{ unit.number }}"></rect>
-        {% endif %}
-        <text x="{{ elevation.rack_x }}" y="{{ unit.y }}" dx="-4" dy="15"
-              class="unit-label" text-anchor="end">{{ unit.number }}</text>
-      </g>
-    {% endfor %}
-
-    {# Devices #}
-    {% for block in elevation.blocks %}
-      <g class="device-block {% if block.opposite %}opposite{% endif %}"
-         data-device-id="{{ block.device.pk }}"
-         data-position="{{ block.device.position }}"
-         data-u-height="{{ block.device.effective_u_height }}"
-         data-width-fraction="{{ block.device.width_fraction }}">
-        <a href="{{ block.device.get_absolute_url }}">
-          <rect x="{{ block.x }}" y="{{ block.y }}" width="{{ block.width }}" height="{{ block.height }}"
-                rx="2" fill="#{{ block.color }}"
-                fill-opacity="{% if block.opposite %}0.35{% else %}1{% endif %}"
-                class="device-rect"></rect>
-          {% comment %}
-            The plain label is always in the markup, image or not - toggling "images
-            only" just layers the (opaque) image on top of it, exactly like NetBox's
-            own rack elevation does. That way there is one code path, not two.
-          {% endcomment %}
-          {% if block.show_text %}
-            <text x="{{ block.x }}" y="{{ block.y }}" dy="15" dx="6"
-                  fill="#{{ block.text_color }}" class="device-label">
-              {{ block.label }}{% if block.opposite %} <tspan class="opposite-hint">({% trans "rear" %})</tspan>{% endif %}
-            </text>
-          {% endif %}
-          {% if block.image %}
-            <clipPath id="concept-block-{{ elevation.face }}-{{ block.device.pk }}">
-              <rect x="{{ block.x }}" y="{{ block.y }}" width="{{ block.width }}" height="{{ block.height }}" rx="2"></rect>
-            </clipPath>
-            <image href="{{ block.image.url }}" x="{{ block.x }}" y="{{ block.y }}"
-                   width="{{ block.width }}" height="{{ block.height }}"
-                   preserveAspectRatio="xMidYMid slice"
-                   clip-path="url(#concept-block-{{ elevation.face }}-{{ block.device.pk }})"
-                   opacity="{% if block.opposite %}0.35{% else %}1{% endif %}"
-                   class="device-image"></image>
-            {% if block.show_text %}
-              {# Outlined white-on-black text, drawn as a stroke pass then a fill pass, so it reads over any image without a background box. #}
-              <text x="{{ block.x }}" y="{{ block.y }}" dy="15" dx="6"
-                    class="device-image-label device-image-label-stroke">{{ block.label }}</text>
-              <text x="{{ block.x }}" y="{{ block.y }}" dy="15" dx="6"
-                    class="device-image-label device-image-label-fill">{{ block.label }}</text>
-            {% endif %}
-          {% endif %}
-          <title>{{ block.label }}{% if block.sublabel %} &middot; {{ block.sublabel }}{% endif %} &middot; U{{ block.device.position }}</title>
-        </a>
-      </g>
-    {% endfor %}
-
-    <rect x="{{ elevation.rack_x }}" y="6"
-          width="{{ elevation.rack_width }}" height="{{ elevation.height|add:'-12' }}"
-          class="rack-frame" fill="none"></rect>
   </svg>
 </div>
-{% endlocalize %}

netbox_rack_concept/templates/netbox_rack_concept/inc/elevation_svg_content.html

@@ -0,0 +1,86 @@
+{% load i18n %}
+{% load l10n %}
+{% comment %}
+  Everything inside one face's <svg>...</svg> - shared by the on-page elevation
+  (inc/elevation.html) and the standalone SVG export (elevation_export.html), so the
+  two never drift apart. Localization is switched off because SVG coordinates must use
+  a dot as the decimal separator whatever the UI language is.
+{% endcomment %}
+{% localize off %}
+{# Unit rows and legend. An empty unit becomes a click target for adding a device
+   here, exactly like a real rack's elevation. #}
+{% for unit in elevation.units %}
+  <g class="unit">
+    {% if not unit.occupied and can_add_device %}
+      <a href="{% url 'plugins:netbox_rack_concept:conceptdevice_add' %}?concept={{ elevation.concept.pk }}&amp;position={{ unit.number }}&amp;face={{ elevation.face }}&amp;return_url={{ elevation.concept.get_absolute_url }}">
+        <rect x="{{ elevation.rack_x }}" y="{{ unit.y }}"
+              width="{{ elevation.rack_width }}" height="{{ unit.height }}"
+              class="unit-slot free"
+              data-unit="{{ unit.number }}"></rect>
+        <text x="{{ elevation.rack_center_x }}" y="{{ unit.y }}" dy="15"
+              class="add-device-hint" text-anchor="middle">+ {% trans "Add device" %}</text>
+      </a>
+    {% else %}
+      <rect x="{{ elevation.rack_x }}" y="{{ unit.y }}"
+            width="{{ elevation.rack_width }}" height="{{ unit.height }}"
+            class="unit-slot"
+            data-unit="{{ unit.number }}"></rect>
+    {% endif %}
+    <text x="{{ elevation.rack_x }}" y="{{ unit.y }}" dx="-4" dy="15"
+          class="unit-label" text-anchor="end">{{ unit.number }}</text>
+  </g>
+{% endfor %}
+
+{# Devices #}
+{% for block in elevation.blocks %}
+  <g class="device-block {% if block.opposite %}opposite{% endif %}"
+     data-device-id="{{ block.device.pk }}"
+     data-position="{{ block.device.position }}"
+     data-u-height="{{ block.device.effective_u_height }}"
+     data-width-fraction="{{ block.device.width_fraction }}">
+    <a href="{{ block.device.get_absolute_url }}">
+      <rect x="{{ block.x }}" y="{{ block.y }}" width="{{ block.width }}" height="{{ block.height }}"
+            rx="2" fill="#{{ block.color }}"
+            fill-opacity="{% if block.opposite %}0.35{% else %}1{% endif %}"
+            class="device-rect"></rect>
+      {% comment %}
+        The plain label is always in the markup, image or not - toggling "images
+        only" just layers the (opaque) image on top of it, exactly like NetBox's
+        own rack elevation does. That way there is one code path, not two.
+      {% endcomment %}
+      {% if block.show_text %}
+        <text x="{{ block.x }}" y="{{ block.y }}" dy="15" dx="6"
+              fill="#{{ block.text_color }}" class="device-label">
+          {{ block.label }}{% if block.opposite %} <tspan class="opposite-hint">({% trans "rear" %})</tspan>{% endif %}
+        </text>
+      {% endif %}
+      {% if block.image %}
+        <clipPath id="concept-block-{{ elevation.face }}-{{ block.device.pk }}">
+          <rect x="{{ block.x }}" y="{{ block.y }}" width="{{ block.width }}" height="{{ block.height }}" rx="2"></rect>
+        </clipPath>
+        {# Absolute when we have a request (the export - a file that outlives the page
+           it came from needs a URL that still resolves once it's saved elsewhere). #}
+        <image href="{% if request %}{{ request.scheme }}://{{ request.get_host }}{% endif %}{{ block.image.url }}"
+               x="{{ block.x }}" y="{{ block.y }}"
+               width="{{ block.width }}" height="{{ block.height }}"
+               preserveAspectRatio="xMidYMid slice"
+               clip-path="url(#concept-block-{{ elevation.face }}-{{ block.device.pk }})"
+               opacity="{% if block.opposite %}0.35{% else %}1{% endif %}"
+               class="device-image"></image>
+        {% if block.show_text %}
+          {# Outlined white-on-black text, drawn as a stroke pass then a fill pass, so it reads over any image without a background box. #}
+          <text x="{{ block.x }}" y="{{ block.y }}" dy="15" dx="6"
+                class="device-image-label device-image-label-stroke">{{ block.label }}</text>
+          <text x="{{ block.x }}" y="{{ block.y }}" dy="15" dx="6"
+                class="device-image-label device-image-label-fill">{{ block.label }}</text>
+        {% endif %}
+      {% endif %}
+      <title>{{ block.label }}{% if block.sublabel %} &middot; {{ block.sublabel }}{% endif %} &middot; U{{ block.device.position }}</title>
+    </a>
+  </g>
+{% endfor %}
+
+<rect x="{{ elevation.rack_x }}" y="6"
+      width="{{ elevation.rack_width }}" height="{{ elevation.height|add:'-12' }}"
+      class="rack-frame" fill="none"></rect>
+{% endlocalize %}

netbox_rack_concept/templates/netbox_rack_concept/rackconcept.html

@@ -140,6 +140,37 @@
           {% if perms.netbox_rack_concept.change_conceptdevice %}
             <span class="badge text-bg-secondary">{% trans "Drag devices to move them" %}</span>
           {% endif %}
+          <div class="dropdown">
+            <button type="button" class="btn btn-outline-secondary btn-sm dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">
+              <i class="mdi mdi-download"></i> {% trans "Export" %}
+            </button>
+            <ul class="dropdown-menu dropdown-menu-end">
+              <li><h6 class="dropdown-header">{% trans "Front" %}</h6></li>
+              <li>
+                <a class="dropdown-item" href="{% url 'plugins:netbox_rack_concept:rackconcept_export_svg' pk=object.pk %}?face=front">SVG</a>
+              </li>
+              <li>
+                <a class="dropdown-item concept-export-png" href="#"
+                   data-svg-url="{% url 'plugins:netbox_rack_concept:rackconcept_export_svg' pk=object.pk %}?face=front"
+                   data-filename="{{ object.name|slugify }}-front.png">PNG</a>
+              </li>
+              <li><h6 class="dropdown-header">{% trans "Rear" %}</h6></li>
+              <li>
+                <a class="dropdown-item" href="{% url 'plugins:netbox_rack_concept:rackconcept_export_svg' pk=object.pk %}?face=rear">SVG</a>
+              </li>
+              <li>
+                <a class="dropdown-item concept-export-png" href="#"
+                   data-svg-url="{% url 'plugins:netbox_rack_concept:rackconcept_export_svg' pk=object.pk %}?face=rear"
+                   data-filename="{{ object.name|slugify }}-rear.png">PNG</a>
+              </li>
+              <li><hr class="dropdown-divider"></li>
+              <li>
+                <a class="dropdown-item" href="{% url 'plugins:netbox_rack_concept:rackconcept_export_drawio' pk=object.pk %}">
+                  {% trans "Draw.io (.drawio)" %}
+                </a>
+              </li>
+            </ul>
+          </div>
         </div>
       </div>
       <div class="card-body">
@@ -172,4 +203,5 @@
 {% block javascript %}
   {{ block.super }}
   <script src="{% static 'netbox_rack_concept/elevation.js' %}"></script>
+  <script src="{% static 'netbox_rack_concept/export.js' %}"></script>
 {% endblock %}

netbox_rack_concept/views.py

@@ -6,18 +6,22 @@ from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.db import transaction
 from django.db.models import Count
-from django.http import HttpResponseForbidden, JsonResponse
+from django.http import HttpResponse, HttpResponseForbidden, JsonResponse
 from django.shortcuts import get_object_or_404, redirect, render
+from django.template.loader import render_to_string
 from django.urls import reverse
+from django.utils.text import slugify
 from django.utils.translation import gettext as _
 from django.views.generic import View
 
+from dcim.choices import DeviceFaceChoices
 from dcim.models import Rack
 from netbox.views import generic
 from utilities.views import ObjectPermissionRequiredMixin, ViewTab, register_model_view
 
 from . import components, deploy, filtersets, forms, tables
 from .choices import ConceptComponentTypeChoices
+from .drawio import build_drawio
 from .elevation import get_elevations
 from .models import ConceptCable, ConceptComponent, ConceptDevice, RackConcept
 
@@ -62,6 +66,45 @@ class RackConceptView(generic.ObjectView):
         }
 
 
+@register_model_view(RackConcept, 'export_svg', path='export/svg')
+class RackConceptExportSVGView(ObjectPermissionRequiredMixin, View):
+    """Download one face's elevation as a standalone SVG file."""
+    queryset = RackConcept.objects.all()
+
+    def get_required_permission(self):
+        return 'netbox_rack_concept.view_rackconcept'
+
+    def get(self, request, pk):
+        concept = get_object_or_404(self.queryset.restrict(request.user, 'view'), pk=pk)
+        face = request.GET.get('face')
+        if face not in (DeviceFaceChoices.FACE_FRONT, DeviceFaceChoices.FACE_REAR):
+            face = DeviceFaceChoices.FACE_FRONT
+
+        front, rear = get_elevations(concept)
+        elevation = front if face == DeviceFaceChoices.FACE_FRONT else rear
+
+        svg = render_to_string('netbox_rack_concept/elevation_export.html', {'elevation': elevation}, request=request)
+        response = HttpResponse(svg, content_type='image/svg+xml')
+        response['Content-Disposition'] = f'attachment; filename="{slugify(concept.name)}-{face}.svg"'
+        return response
+
+
+@register_model_view(RackConcept, 'export_drawio', path='export/drawio')
+class RackConceptExportDrawioView(ObjectPermissionRequiredMixin, View):
+    """Download both faces of a concept as one draw.io (diagrams.net) diagram."""
+    queryset = RackConcept.objects.all()
+
+    def get_required_permission(self):
+        return 'netbox_rack_concept.view_rackconcept'
+
+    def get(self, request, pk):
+        concept = get_object_or_404(self.queryset.restrict(request.user, 'view'), pk=pk)
+        xml = build_drawio(concept)
+        response = HttpResponse(xml, content_type='application/xml')
+        response['Content-Disposition'] = f'attachment; filename="{slugify(concept.name)}.drawio"'
+        return response
+
+
 @register_model_view(RackConcept, 'devices')
 class RackConceptDevicesView(generic.ObjectChildrenView):
     queryset = RackConcept.objects.all()