import { GoogleGenAI } from "@google/genai";
import { GenerateImageArgs, GeneratedImage } from "../types.js";
import { saveBase64Image } from "../utils/fs.js";
const DEFAULT_MODEL = "gemini-2.5-flash-image-preview";
export async function generateImageGemini(args: GenerateImageArgs): Promise<GeneratedImage> {
const apiKey = process.env.GOOGLE_API_KEY;
if (!apiKey) throw new Error("Missing GOOGLE_API_KEY environment variable");
const model = args.model || process.env.GOOGLE_IMAGE_MODEL || DEFAULT_MODEL;
const ai = new GoogleGenAI({ apiKey });
// The new SDK accepts contents as a string for simple prompts
const response = await ai.models.generateContent({
model,
contents: args.prompt,
} as any);
const candidates = (response as any)?.candidates || [];
if (!candidates.length) throw new Error("Gemini returned no candidates");
// Find the first inline image part
let base64: string | undefined;
let mimeType: string = "image/png";
outer: for (const c of candidates) {
const parts = c?.content?.parts || [];
for (const p of parts) {
if (p?.inlineData?.data) {
base64 = p.inlineData.data as string;
if (p.inlineData.mimeType) mimeType = p.inlineData.mimeType as string;
break outer;
}
}
}
if (!base64) {
// If the model responded with text, surface it for debugging
const texts: string[] = [];
for (const c of candidates) {
const parts = c?.content?.parts || [];
for (const p of parts) if (p?.text) texts.push(p.text as string);
}
const msg = texts.length ? `Gemini returned text instead of image: ${texts.join(" | ")}` : "Gemini returned no image data";
throw new Error(msg);
}
const ext = mimeType.includes("png") ? "png" : mimeType.includes("jpeg") || mimeType.includes("jpg") ? "jpg" : mimeType.includes("webp") ? "webp" : "png";
const outputDir = process.env.OUTPUT_DIR || "outputs";
const name = (args.filenameHint || "gemini-image")
.toLowerCase()
.replace(/[^a-z0-9-_]+/g, "-")
.replace(/-+/g, "-")
.replace(/^-|-$/g, "");
const filename = `${Date.now()}-${name || "image"}.${ext}`;
const path = saveBase64Image(base64, outputDir, filename);
return {
path,
mimeType,
base64: args.returnBase64 ? base64 : undefined,
provider: "google",
model,
};
}
