import { GoogleGenAI } from "@google/genai";
import type { DetailLevel } from "./validators.js";
export class VideoAnalysisError extends Error {
constructor(message: string) {
super(message);
this.name = "VideoAnalysisError";
}
}
export class VideoAccessError extends VideoAnalysisError {
constructor(url: string, cause?: Error) {
super(
`Cannot access video: ${url}. Ensure video is public and not geo-restricted.`
);
this.name = "VideoAccessError";
this.cause = cause;
}
}
const DETAIL_PROMPTS: Record<DetailLevel, string> = {
brief: "Summarize this video in 2-3 sentences, capturing the main point.",
medium:
"Summarize this video with key points. Include timestamps (MM:SS format) for important moments.",
detailed:
"Provide a comprehensive breakdown of this video. Include: main topics, key points with timestamps, important quotes or statements, and a conclusion.",
};
export class GeminiVideoClient {
private client: GoogleGenAI;
private model: string;
constructor() {
const apiKey = process.env.GEMINI_API_KEY;
if (!apiKey) {
throw new Error(
"GEMINI_API_KEY environment variable is required. Set it before starting the server."
);
}
this.client = new GoogleGenAI({ apiKey });
this.model = process.env.GEMINI_MODEL || "gemini-2.5-flash";
}
async summarize(youtubeUrl: string, detailLevel: DetailLevel): Promise<string> {
const prompt = DETAIL_PROMPTS[detailLevel];
return this.analyze(youtubeUrl, prompt);
}
async ask(youtubeUrl: string, question: string): Promise<string> {
const prompt = `Based on this video, answer the following question:\n\n${question}`;
return this.analyze(youtubeUrl, prompt);
}
private async analyze(youtubeUrl: string, prompt: string): Promise<string> {
try {
const response = await this.client.models.generateContent({
model: this.model,
contents: [
{
role: "user",
parts: [
{
fileData: {
fileUri: youtubeUrl,
},
},
{
text: prompt,
},
],
},
],
});
const text = response.text;
if (!text) {
throw new VideoAnalysisError("Gemini returned an empty response");
}
return text;
} catch (error) {
if (error instanceof VideoAnalysisError) {
throw error;
}
const message = error instanceof Error ? error.message : String(error);
if (
message.toLowerCase().includes("video") ||
message.toLowerCase().includes("file") ||
message.toLowerCase().includes("access")
) {
throw new VideoAccessError(
youtubeUrl,
error instanceof Error ? error : undefined
);
}
if (
message.toLowerCase().includes("quota") ||
message.toLowerCase().includes("rate")
) {
throw new VideoAnalysisError(
"API quota exceeded or rate limited. Please try again later."
);
}
throw new VideoAnalysisError(`Failed to analyze video: ${message}`);
}
}
}
