feat(sign): 支持多位置签名并优化坐标识别与模板版本校验

2026-09-30 18:14:22 +08:00
parent 69825dfa0a
commit e5f0a5ec97
17 changed files with 622 additions and 229 deletions
@@ -230,3 +230,52 @@ export async function fetchSignatureDataUrl(artifact: SigningArtifact): Promise<
    return ''
  }
 }
+
+/** Restore each position from the lossless evidence sheet; legacy images remain supported. */
+export async function fetchSignatureImages(
+  artifact: SigningArtifact,
+): Promise<Record<string, string>> {
+  const source = await fetchSignatureDataUrl(artifact)
+  if (!source) return {}
+  const entries = artifact.metadata.signatures
+  if (!Array.isArray(entries))
+    return { [String(artifact.metadata.signatureFieldId || 'signature')]: source }
+  if (!entries.length) return {}
+  const image = new Image()
+  image.src = source
+  await image.decode()
+  const result: Record<string, string> = {}
+  for (const entry of entries) {
+    if (!entry || typeof entry !== 'object') continue
+    const { field, sourceX, sourceY, imageWidth, imageHeight } = entry
+    if (
+      typeof field?.id !== 'string' ||
+      ![sourceX, sourceY, imageWidth, imageHeight].every(Number.isInteger) ||
+      sourceX < 0 ||
+      sourceY < 0 ||
+      imageWidth <= 0 ||
+      imageHeight <= 0 ||
+      sourceX + imageWidth > image.naturalWidth ||
+      sourceY + imageHeight > image.naturalHeight
+    )
+      continue
+    const canvas = document.createElement('canvas')
+    canvas.width = imageWidth
+    canvas.height = imageHeight
+    const context = canvas.getContext('2d')
+    if (!context) continue
+    context.drawImage(
+      image,
+      sourceX,
+      sourceY,
+      imageWidth,
+      imageHeight,
+      0,
+      0,
+      imageWidth,
+      imageHeight,
+    )
+    result[field.id] = canvas.toDataURL('image/png')
+  }
+  return result
+}