Support Images and PDFs (#447)

packages/server/src/core/geminiRequest.ts

@@ -0,0 +1,71 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { type PartListUnion, type Part } from '@google/genai';
+
+/**
+ * Represents a request to be sent to the Gemini API.
+ * For now, it's an alias to PartListUnion as the primary content.
+ * This can be expanded later to include other request parameters.
+ */
+export type GeminiCodeRequest = PartListUnion;
+
+export function partListUnionToString(value: PartListUnion): string {
+  if (typeof value === 'string') {
+    return value;
+  }
+
+  if (Array.isArray(value)) {
+    return value.map(partListUnionToString).join('');
+  }
+
+  // Cast to Part, assuming it might contain project-specific fields
+  const part = value as Part & {
+    videoMetadata?: unknown;
+    thought?: string;
+    codeExecutionResult?: unknown;
+    executableCode?: unknown;
+  };
+
+  if (part.videoMetadata !== undefined) {
+    return `[Video Metadata]`;
+  }
+
+  if (part.thought !== undefined) {
+    return `[Thought: ${part.thought}]`;
+  }
+
+  if (part.codeExecutionResult !== undefined) {
+    return `[Code Execution Result]`;
+  }
+
+  if (part.executableCode !== undefined) {
+    return `[Executable Code]`;
+  }
+
+  // Standard Part fields
+  if (part.fileData !== undefined) {
+    return `[File Data]`;
+  }
+
+  if (part.functionCall !== undefined) {
+    return `[Function Call: ${part.functionCall.name}]`;
+  }
+
+  if (part.functionResponse !== undefined) {
+    return `[Function Response: ${part.functionResponse.name}]`;
+  }
+
+  if (part.inlineData !== undefined) {
+    return `<${part.inlineData.mimeType}>`;
+  }
+
+  if (part.text !== undefined) {
+    return part.text;
+  }
+
+  return '';
+}