/**
* Gemini API client for image generation
*/
import { GoogleGenAI } from '@google/genai';
import * as fs from 'node:fs';
import * as path from 'node:path';
import { GenerationResult, DEFAULT_MODEL } from '../types.js';
let client: GoogleGenAI | null = null;
function getClient(): GoogleGenAI {
if (!client) {
const apiKey = process.env.GEMINI_API_KEY;
if (!apiKey) {
throw new Error(
'GEMINI_API_KEY not set. Get one at https://aistudio.google.com/apikey'
);
}
client = new GoogleGenAI({ apiKey });
}
return client;
}
export interface GenerateImageOptions {
prompt: string;
outputPath: string;
model?: string;
aspectRatio?: string;
overwrite?: boolean;
baseDir?: string;
}
export async function generateImage(
options: GenerateImageOptions
): Promise<GenerationResult> {
const {
prompt,
outputPath,
model = DEFAULT_MODEL,
aspectRatio,
overwrite = false,
baseDir = process.cwd()
} = options;
const startTime = Date.now();
// Resolve output path
const resolvedPath = path.isAbsolute(outputPath)
? outputPath
: path.resolve(baseDir, outputPath);
// Check if file exists
if (fs.existsSync(resolvedPath) && !overwrite) {
return {
success: true,
output_path: resolvedPath,
model_used: model,
generation_time_ms: Date.now() - startTime,
skipped: true
};
}
try {
const ai = getClient();
// Build generation config
const config: Record<string, unknown> = {};
if (aspectRatio) {
config.aspectRatio = aspectRatio;
}
// Generate image
const response = await ai.models.generateContent({
model,
contents: prompt,
config: Object.keys(config).length > 0 ? config : undefined
});
// Extract image from response
let imageData: string | null = null;
let promptTokens: number | undefined;
if (response.candidates?.[0]?.content?.parts) {
for (const part of response.candidates[0].content.parts) {
if ('inlineData' in part && part.inlineData) {
imageData = part.inlineData.data as string;
break;
}
}
}
// Get token usage if available
if (response.usageMetadata) {
promptTokens = response.usageMetadata.promptTokenCount;
}
if (!imageData) {
// Check if there's text explaining why no image was generated
let errorText = 'No image data in response';
if (response.candidates?.[0]?.content?.parts) {
for (const part of response.candidates[0].content.parts) {
if ('text' in part && part.text) {
errorText = part.text;
break;
}
}
}
return {
success: false,
output_path: resolvedPath,
model_used: model,
generation_time_ms: Date.now() - startTime,
skipped: false,
error: errorText
};
}
// Ensure directory exists
const dir = path.dirname(resolvedPath);
if (!fs.existsSync(dir)) {
fs.mkdirSync(dir, { recursive: true });
}
// Save image
const buffer = Buffer.from(imageData, 'base64');
fs.writeFileSync(resolvedPath, buffer);
return {
success: true,
output_path: resolvedPath,
model_used: model,
prompt_tokens: promptTokens,
generation_time_ms: Date.now() - startTime,
skipped: false
};
} catch (error) {
const errorMessage = error instanceof Error ? error.message : String(error);
return {
success: false,
output_path: resolvedPath,
model_used: model,
generation_time_ms: Date.now() - startTime,
skipped: false,
error: errorMessage
};
}
}
