Next.js AI Race Plan Builder

I need a self-contained Next.js module I can drop into my existing site that turns a runner’s inputs into a polished race-day plan. Runners will fill out a short form covering 1) race details and preferences, 2) their personal running statistics, and 3) any medical or dietary information they feel is relevant. Behind the scenes the app should combine rule-based logic (cut-off times, hydration ratios, taper length, etc.) with generative AI capable of delivering highly personalized recommendations—the AI angle is what will set this apart from generic calculators.

Core flow
• Collect the three input categories through a clean, responsive Next.js form.
• Feed the data to an AI layer (OpenAI, Vertex, or similar—open to your suggestion).
• Blend AI output with my hard rules so the final document is both creative and compliant.
• Return a neatly formatted race plan (PDF + on-screen) that the runner can save or share.

Deliverables
• Source-controlled Next.js code with clear component structure.
• Prompt engineering / function calls that drive the personalized recommendations.
• Rule engine or middleware showing where my fixed logic lives.
• PDF generation script or service.
• Brief README so I can redeploy and adjust rules myself.

Acceptance
A sample user should be able to enter a marathon in under 5 minutes and receive a coherent plan that references their pace history, nutrition needs, and stated preferences. If the plan omits any of those three data groups, it isn’t done.

If you have recent experience marrying React/Next.js with Gen AI APIs and PDF output, you’ll cruise through this. Let’s build something runners will actually trust on race day.