init

src/lib/fileLoader.ts

@@ -0,0 +1,53 @@
+export function readAsDataUrl(file: File): Promise<string> {
+  return new Promise((resolve, reject) => {
+    const reader = new FileReader()
+    reader.onload = () => resolve(reader.result as string)
+    reader.onerror = () => reject(reader.error)
+    reader.readAsDataURL(file)
+  })
+}
+
+export function loadImage(src: string): Promise<HTMLImageElement> {
+  return new Promise((resolve, reject) => {
+    const img = new Image()
+    img.crossOrigin = 'anonymous'
+    img.onload = () => resolve(img)
+    img.onerror = () => reject(new Error(`failed to load image: ${src.slice(0, 60)}…`))
+    img.src = src
+  })
+}
+
+export interface Dimensions {
+  width: number
+  height: number
+}
+
+export function parseSvgDimensions(svgText: string): Dimensions | null {
+  const doc = new DOMParser().parseFromString(svgText, 'image/svg+xml')
+  const svg = doc.documentElement
+  if (!svg || svg.nodeName !== 'svg') return null
+
+  const parseLen = (attr: string | null) => {
+    if (!attr) return 0
+    const num = parseFloat(attr)
+    return Number.isFinite(num) ? num : 0
+  }
+
+  let w = parseLen(svg.getAttribute('width'))
+  let h = parseLen(svg.getAttribute('height'))
+
+  if (!w || !h) {
+    const vb = svg.getAttribute('viewBox')?.trim().split(/[\s,]+/).map(Number)
+    if (vb && vb.length === 4 && vb.every((n) => Number.isFinite(n))) {
+      if (!w) w = vb[2]
+      if (!h) h = vb[3]
+    }
+  }
+
+  if (!w || !h) return null
+  return { width: w, height: h }
+}
+
+export function isSvgFile(file: File): boolean {
+  return file.type === 'image/svg+xml' || file.name.toLowerCase().endsWith('.svg')
+}