I have verified that the index.html file correctly includes the `ma…

[Giom-V]

…gic_mirror.js` script and that the script contains all the necessary logic for the application to run.

[gemini-code-assist]

Summary of Changes

Hello @Giom-V, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request completely refactors the quickstarts-js directory by removing the extensive Get_Started.js example and introducing a new, interactive "Magic Mirror" web application. The new application demonstrates the Gemini API's image generation capabilities, allowing users to capture their webcam feed and transform it into a "princess" image, accompanied by witty, rhyming responses from an AI-powered "magic mirror."

Highlights

• Replaced comprehensive quickstart: The previous quickstarts-js/Get_Started.js file, which contained a broad range of Gemini API examples, has been removed.
• Introduced "Magic Mirror" application: A new web-based application is introduced, featuring an index.html for the user interface and magic_mirror.js for its functionality.
• Webcam integration and image generation: The magic_mirror.js script captures live webcam input, sends it to the Gemini API (gemini-2.5-flash-image-preview model), and displays the AI-generated image transformation.
• Persona-driven AI interaction: The application utilizes Gemini's system instruction feature to make the "magic mirror" respond in a witty, sassy, and rhyming manner, enhancing user engagement.

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[gemini-code-assist]

Code Review

This pull request introduces a new 'Magic Mirror' web application example, which is a great addition. However, it also removes the comprehensive Get_Started.js quickstart file. This is a significant change that isn't mentioned in the pull request description and will require an update to the quickstarts-js/README.md to avoid broken links and confusion for users.

I've found a critical issue in magic_mirror.js where the API key is accessed using process.env.GEMINI_API_KEY. This is a Node.js environment variable and will not work in a browser, preventing the application from functioning. I've also added comments regarding error handling, safe data access, and coding conventions to improve the robustness and consistency of the new code.

[gemini-code-assist]

process.env.GEMINI_API_KEY is a Node.js feature and is not available in the browser. This will cause a ReferenceError: process is not defined and the application will fail to initialize the GenAI client. For a client-side demo application, a simple approach is to prompt the user to enter their API key.

Suggested change

	const ai = new GoogleGenAI({ apiKey: process.env.GEMINI_API_KEY });
	const ai = new GoogleGenAI({ apiKey: window.prompt("Please enter your Gemini API Key:") });

[gemini-code-assist]

This function lacks error handling for the API call and has unsafe access to the response object. If generateContent fails or returns no candidates (e.g., due to safety filters), the app will either have an unhandled error or throw a TypeError. It's better to wrap the logic in a try...catch block and check for the existence of candidates before processing them. This suggestion refactors the function to be more robust.

async function edit_camera_image() {
    try {
        const context = canvas.getContext('2d');
        context.drawImage(video, 0, 0, 640, 480);
        const dataUrl = canvas.toDataURL('image/png');
        const imageData = dataUrl.split(',')[1]; // Get only base64 string

        const imagePart = {
            inlineData: {
                data: imageData,
                mimeType: "image/png"
            }
        };

        const response = await ai.models.generateContent({
            model: MODEL_ID,
            contents: [imagePart, 'Mirror, mirror on the wall, make me a princess after all!'],
            config: {
                systemInstruction: "You are a magic mirror. You are witty, a bit sassy, and you always speak in rhymes. You are here to make people's dreams come true, but you do it with a bit of flair and humor.",
            }
        });

        const candidate = response?.candidates?.[0];
        if (candidate) {
            for (const part of candidate.content.parts) {
                if (part.text) {
                    speech.textContent = part.text;
                }
                if (part.inlineData) {
                    const base64ImageBytes = part.inlineData.data;
                    const imageUrl = `data:image/png;base64,${base64ImageBytes}`;
                    result.src = imageUrl;
                }
            }
        } else {
            speech.textContent = "The mirror has nothing to show or say... Try again?";
        }
    } catch (err) {
        console.error("Error generating content:", err);
        speech.textContent = "Oops! The magic mirror is a bit shy today. Please try again.";
    }
}

[gemini-code-assist]

The function name edit_camera_image uses snake_case. While the provided style guide is for Python, the common convention for JavaScript is camelCase (editCameraImage). Using camelCase would also make it consistent with the startWebcam function in this file. Remember to update the function definition on line 44 as well.

Suggested change

	snap.addEventListener('click', edit_camera_image);
	snap.addEventListener('click', editCameraImage);