Phase 2: Canvas Editor Core

Implements the core canvas editor with react-konva:

- Added dependencies: react-konva, konva, use-image
- DesignCanvas component: 300×300px Stage with T-shirt SVG overlay
- TShirtSVG component: Visual t-shirt outline with print zone indicator
- ImageElement: Draggable/resizable image with Transformer handles
- TextElement: Draggable/resizable text with Transformer handles
- useDesignEditor hook: Element CRUD, selection, reordering
- Keyboard shortcut: Delete/Backspace removes selected element
- Test image added on mount for Phase 2 verification

Canvas info bar shows: "Design Area: 15" × 15" • Export: 4500 × 4500px @ 300 DPI"

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/package.json

@@ -11,7 +11,10 @@
   },
   "dependencies": {
     "react": "^19.2.5",
-    "react-dom": "^19.2.5"
+    "react-dom": "^19.2.5",
+    "react-konva": "^18.2.10",
+    "konva": "^9.3.18",
+    "use-image": "^1.1.1"
   },
   "devDependencies": {
     "@eslint/js": "^9.39.4",

client/src/App.jsx

@@ -1,12 +1,82 @@
+import { useEffect, useCallback } from 'react';
+import { DesignCanvas } from './components/canvas/DesignCanvas';
+import { useDesignEditor } from './hooks/useDesignEditor';
+
 function App() {
+  const {
+    elements,
+    selectedId,
+    addElement,
+    updateElement,
+    deleteElement,
+    selectElement,
+    deselectAll,
+  } = useDesignEditor();
+
+  // Keyboard shortcut: Delete/Backspace removes selected element
+  useEffect(() => {
+    const handleKeyDown = (e) => {
+      // Don't delete if user is typing in an input
+      if (e.target.tagName === 'INPUT' || e.target.tagName === 'TEXTAREA') {
+        return;
+      }
+      if (e.key === 'Delete' || e.key === 'Backspace') {
+        if (selectedId) {
+          deleteElement(selectedId);
+        }
+      }
+    };
+
+    window.addEventListener('keydown', handleKeyDown);
+    return () => window.removeEventListener('keydown', handleKeyDown);
+  }, [selectedId, deleteElement]);
+
+  // Test: Add sample image on mount (for Phase 2 testing)
+  useEffect(() => {
+    // Add a test image element
+    const testImageId = addElement({
+      type: 'image',
+      x: 75,
+      y: 75,
+      width: 150,
+      height: 150,
+      rotation: 0,
+      src: 'https://placehold.co/150x150/38bdf8/ffffff?text=Test',
+    });
+    console.log('Added test image with ID:', testImageId);
+  }, []); // eslint-disable-line react-hooks/exhaustive-deps
+
   return (
     <div style={{ padding: '2rem', textAlign: 'center' }}>
       <h1>Apparel Designer</h1>
-      <p style={{ color: 'var(--text-secondary)' }}>
+      <p style={{ color: 'var(--text-secondary)', marginBottom: '2rem' }}>
         T-shirt customization editor
       </p>
-      <div style={{ marginTop: '2rem', padding: '1rem', background: 'var(--bg-secondary)', borderRadius: 'var(--radius-md)' }}>
-        <p>Server Status: <code id="server-status">Checking...</code></p>
+
+      {/* Canvas container */}
+      <div style={{ marginBottom: '2rem' }}>
+        <DesignCanvas
+          elements={elements}
+          selectedId={selectedId}
+          onSelect={selectElement}
+          onDeselect={deselectAll}
+          onUpdate={updateElement}
+        />
+      </div>
+
+      {/* Debug info */}
+      <div style={{
+        padding: '1rem',
+        background: 'var(--bg-secondary)',
+        borderRadius: 'var(--radius-md)',
+        maxWidth: '400px',
+        margin: '0 auto',
+      }}>
+        <p>Elements: {elements.length}</p>
+        <p>Selected: {selectedId || 'None'}</p>
+        <p style={{ fontSize: '12px', color: 'var(--text-muted)' }}>
+          Tip: Click to select, drag to move, use handles to resize. Press Delete to remove.
+        </p>
       </div>
     </div>
   );

client/src/components/canvas/DesignCanvas.jsx

@@ -0,0 +1,95 @@
+import { Stage, Layer } from 'react-konva';
+import { TShirtSVG } from './TShirtSVG';
+import { ImageElement } from './ImageElement';
+import { TextElement } from './TextElement';
+
+const CANVAS_SIZE = 300;
+
+export function DesignCanvas({
+  elements,
+  selectedId,
+  onSelect,
+  onDeselect,
+  onUpdate,
+}) {
+  return (
+    <div style={{ position: 'relative', display: 'inline-block' }}>
+      {/* T-shirt SVG background */}
+      <TShirtSVG size={CANVAS_SIZE} />
+
+      {/* Canvas Stage */}
+      <Stage
+        width={CANVAS_SIZE}
+        height={CANVAS_SIZE}
+        onClick={onDeselect}
+        onTap={onDeselect}
+        style={{
+          position: 'absolute',
+          top: '50%',
+          left: '50%',
+          transform: 'translate(-50%, -50%)',
+          border: selectedId ? '2px solid #38bdf8' : '1px dashed #cbd5e1',
+          borderRadius: '8px',
+          background: 'rgba(255, 255, 255, 0.5)',
+        }}
+      >
+        <Layer>
+          {elements.map((el) => {
+            if (el.type === 'image') {
+              return (
+                <ImageElement
+                  key={el.id}
+                  id={el.id}
+                  x={el.x}
+                  y={el.y}
+                  width={el.width}
+                  height={el.height}
+                  rotation={el.rotation}
+                  src={el.src}
+                  isSelected={el.id === selectedId}
+                  onSelect={() => onSelect(el.id)}
+                  onUpdate={(attrs) => onUpdate(el.id, attrs)}
+                />
+              );
+            }
+            if (el.type === 'text') {
+              return (
+                <TextElement
+                  key={el.id}
+                  id={el.id}
+                  x={el.x}
+                  y={el.y}
+                  text={el.text}
+                  fontSize={el.fontSize}
+                  fontFamily={el.fontFamily}
+                  fill={el.fill}
+                  rotation={el.rotation}
+                  isSelected={el.id === selectedId}
+                  onSelect={() => onSelect(el.id)}
+                  onUpdate={(attrs) => onUpdate(el.id, attrs)}
+                />
+              );
+            }
+            return null;
+          })}
+        </Layer>
+      </Stage>
+
+      {/* Canvas info bar */}
+      <div
+        style={{
+          position: 'absolute',
+          bottom: '-40px',
+          left: '50%',
+          transform: 'translateX(-50%)',
+          fontSize: '12px',
+          color: 'var(--text-secondary)',
+          textAlign: 'center',
+          whiteSpace: 'nowrap',
+        }}
+      >
+        Design Area: 15" × 15" • Export: 4500 × 4500px @ 300 DPI
+      </div>
+    </div>
+  );
+}

client/src/components/canvas/ImageElement.jsx

@@ -0,0 +1,98 @@
+import { useEffect, useState } from 'react';
+import { Image, Transformer } from 'react-konva';
+import useImage from 'use-image';
+
+function URLImage({ src, ...props }) {
+  const [img] = useImage(src, 'anonymous');
+  return <Image image={img} {...props} />;
+}
+
+export function ImageElement({
+  id,
+  x,
+  y,
+  width,
+  height,
+  rotation,
+  src,
+  isSelected,
+  onSelect,
+  onUpdate,
+}) {
+  const shapeRef = null;
+  const trRef = null;
+
+  useEffect(() => {
+    if (isSelected && trRef.current) {
+      trRef.current.nodes([shapeRef.current]);
+      trRef.current.getLayer().batchDraw();
+    }
+  }, [isSelected]);
+
+  return (
+    <>
+      <URLImage
+        ref={shapeRef}
+        x={x}
+        y={y}
+        width={width}
+        height={height}
+        rotation={rotation}
+        src={src}
+        draggable
+        onClick={onSelect}
+        onTap={onSelect}
+        onDragEnd={(e) => {
+          onUpdate({
+            x: e.target.x(),
+            y: e.target.y(),
+          });
+        }}
+        onTransformEnd={(e) => {
+          const node = shapeRef.current;
+          const scaleX = node.scaleX();
+          const scaleY = node.scaleY();
+          node.scaleX(1);
+          node.scaleY(1);
+          onUpdate({
+            x: node.x(),
+            y: node.y(),
+            width: Math.max(20, node.width() * scaleX),
+            height: Math.max(20, node.height() * scaleY),
+            rotation: node.rotation(),
+          });
+        }}
+        boundBoxFunc={(oldBox, newBox) => {
+          // Minimum size constraint
+          if (newBox.width < 20 || newBox.height < 20) {
+            return oldBox;
+          }
+          return newBox;
+        }}
+      />
+      {isSelected && (
+        <Transformer
+          ref={trRef}
+          boundBoxFunc={(oldBox, newBox) => {
+            // Limit resize to minimum size
+            if (newBox.width < 20 || newBox.height < 20) {
+              return oldBox;
+            }
+            return newBox;
+          }}
+          anchorSize={8}
+          anchorCornerRadius={4}
+          borderStroke="#38bdf8"
+          anchorStroke="#38bdf8"
+          anchorFill="#ffffff"
+        />
+      )}
+    </>
+  );
+}
+
+ImageElement.defaultProps = {
+  width: 100,
+  height: 100,
+  rotation: 0,
+};

client/src/components/canvas/TShirtSVG.jsx

@@ -0,0 +1,59 @@
+export function TShirtSVG({ size = 300 }) {
+  const padding = size * 0.1;
+  const innerSize = size - padding * 2;
+
+  return (
+    <svg
+      width={size}
+      height={size}
+      viewBox={`0 0 ${size} ${size}`}
+      style={{
+        position: 'absolute',
+        top: '50%',
+        left: '50%',
+        transform: 'translate(-50%, -50%)',
+        pointerEvents: 'none',
+        zIndex: 0,
+      }}
+    >
+      {/* T-shirt outline */}
+      <path
+        d={`
+          M ${padding} ${padding + innerSize * 0.15}
+          L ${padding + innerSize * 0.15} ${padding}
+          L ${size - padding - innerSize * 0.15} ${padding}
+          L ${size - padding} ${padding + innerSize * 0.15}
+          L ${size - padding} ${size - padding}
+          L ${padding} ${size - padding}
+          Z
+        `}
+        fill="none"
+        stroke="var(--border)"
+        strokeWidth="2"
+        strokeDasharray="4,4"
+      />
+      {/* Chest area indicator (design zone) */}
+      <rect
+        x={size * 0.3}
+        y={size * 0.25}
+        width={size * 0.4}
+        height={size * 0.35}
+        fill="none"
+        stroke="var(--accent)"
+        strokeWidth="1.5"
+        opacity="0.5"
+      />
+      {/* Label */}
+      <text
+        x={size / 2}
+        y={size * 0.45}
+        textAnchor="middle"
+        fill="var(--text-muted)"
+        fontSize="10"
+        fontFamily="var(--font-mono)"
+      >
+        Print Zone
+      </text>
+    </svg>
+  );
+}

client/src/components/canvas/TextElement.jsx

@@ -0,0 +1,80 @@
+import { useEffect } from 'react';
+import { Text, Transformer } from 'react-konva';
+
+export function TextElement({
+  id,
+  x,
+  y,
+  text,
+  fontSize,
+  fontFamily,
+  fill,
+  rotation,
+  isSelected,
+  onSelect,
+  onUpdate,
+}) {
+  const textRef = null;
+  const trRef = null;
+
+  useEffect(() => {
+    if (isSelected && trRef.current) {
+      trRef.current.nodes([textRef.current]);
+      trRef.current.getLayer().batchDraw();
+    }
+  }, [isSelected]);
+
+  return (
+    <>
+      <Text
+        ref={textRef}
+        x={x}
+        y={y}
+        text={text}
+        fontSize={fontSize}
+        fontFamily={fontFamily}
+        fill={fill}
+        rotation={rotation}
+        draggable
+        onClick={onSelect}
+        onTap={onSelect}
+        onDragEnd={(e) => {
+          onUpdate({
+            x: e.target.x(),
+            y: e.target.y(),
+          });
+        }}
+        onTransformEnd={(e) => {
+          const node = textRef.current;
+          const scaleX = node.scaleX();
+          node.scaleX(1);
+          node.scaleY(1);
+          onUpdate({
+            x: node.x(),
+            y: node.y(),
+            fontSize: Math.max(12, node.fontSize() * scaleX),
+            rotation: node.rotation(),
+          });
+        }}
+      />
+      {isSelected && (
+        <Transformer
+          ref={trRef}
+          enabledAnchors={['top-left', 'top-right', 'bottom-left', 'bottom-right']}
+          anchorSize={8}
+          anchorCornerRadius={4}
+          borderStroke="#38bdf8"
+          anchorStroke="#38bdf8"
+          anchorFill="#ffffff"
+        />
+      )}
+    </>
+  );
+}
+
+TextElement.defaultProps = {
+  fontSize: 24,
+  fontFamily: 'DM Sans',
+  fill: '#0f172a',
+  rotation: 0,
+};

client/src/components/canvas/index.js

@@ -0,0 +1,4 @@
+export { DesignCanvas } from './DesignCanvas';
+export { TShirtSVG } from './TShirtSVG';
+export { ImageElement } from './ImageElement';
+export { TextElement } from './TextElement';

client/src/hooks/index.js

@@ -0,0 +1 @@
+export { useDesignEditor } from './useDesignEditor';

client/src/hooks/useDesignEditor.js

@@ -0,0 +1,59 @@
+import { useState, useCallback } from 'react';
+
+export function useDesignEditor() {
+  const [elements, setElements] = useState([]);
+  const [selectedId, setSelectedId] = useState(null);
+
+  const addElement = useCallback((element) => {
+    const newElement = {
+      ...element,
+      id: `element-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
+    };
+    setElements((prev) => [...prev, newElement]);
+    setSelectedId(newElement.id);
+    return newElement.id;
+  }, []);
+
+  const updateElement = useCallback((id, attrs) => {
+    setElements((prev) =>
+      prev.map((el) => (el.id === id ? { ...el, ...attrs } : el))
+    );
+  }, []);
+
+  const deleteElement = useCallback((id) => {
+    setElements((prev) => prev.filter((el) => el.id !== id));
+    if (selectedId === id) {
+      setSelectedId(null);
+    }
+  }, [selectedId]);
+
+  const selectElement = useCallback((id) => {
+    setSelectedId(id);
+  }, []);
+
+  const deselectAll = useCallback(() => {
+    setSelectedId(null);
+  }, []);
+
+  const reorderElement = useCallback((id, newOrder) => {
+    setElements((prev) => {
+      const index = prev.findIndex((el) => el.id === id);
+      if (index === -1 || index === newOrder) return prev;
+      const newElements = [...prev];
+      const [removed] = newElements.splice(index, 1);
+      newElements.splice(newOrder, 0, removed);
+      return newElements;
+    });
+  }, []);
+
+  return {
+    elements,
+    selectedId,
+    addElement,
+    updateElement,
+    deleteElement,
+    selectElement,
+    deselectAll,
+    reorderElement,
+  };
+}

client/src/main.jsx

@@ -1,31 +1,10 @@
-import { StrictMode, useEffect, useState } from 'react'
+import { StrictMode } from 'react'
 import { createRoot } from 'react-dom/client'
 import './index.css'
-
-function AppWithHealth() {
-  const [serverStatus, setServerStatus] = useState('Checking...');
-
-  useEffect(() => {
-    fetch('/api/health')
-      .then(res => res.ok ? setServerStatus('Connected ✓') : setServerStatus('Error'))
-      .catch(() => setServerStatus('Offline'));
-  }, []);
-
-  return (
-    <div style={{ padding: '2rem', textAlign: 'center' }}>
-      <h1>Apparel Designer</h1>
-      <p style={{ color: 'var(--text-secondary)' }}>
-        T-shirt customization editor
-      </p>
-      <div style={{ marginTop: '2rem', padding: '1rem', background: 'var(--bg-secondary)', borderRadius: 'var(--radius-md)' }}>
-        <p>Server Status: <code id="server-status">{serverStatus}</code></p>
-      </div>
-    </div>
-  );
-}
+import App from './App'
 
 createRoot(document.getElementById('root')).render(
   <StrictMode>
-    <AppWithHealth />
+    <App />
   </StrictMode>,
 )