app.py

import io, os, uuid
from typing import List
from fastapi import FastAPI, File, UploadFile, Form, HTTPException
from fastapi.responses import StreamingResponse
from pptx import Presentation
from pptx.util import Inches

app = FastAPI(title="Images to PPT")

def build_ppt_from_uploads(files: List[UploadFile], fit="height", height_inches=6.5, margin_inches=0.5) -> bytes:
    prs = Presentation()
    blank = prs.slide_layouts[6]
    for f in files:
        if f.content_type and not f.content_type.startswith("image/"):
            # allow only images
            raise HTTPException(status_code=400, detail=f"Unsupported file type: {f.filename}")
        img_bytes = f.file.read()
        # write to temp on disk because python-pptx needs a file-like path or stream
        temp_name = f"{uuid.uuid4()}_{f.filename or 'image'}"
        with open(temp_name, "wb") as tmp:
            tmp.write(img_bytes)
        slide = prs.slides.add_slide(blank)
        if fit == "height":
            slide.shapes.add_picture(temp_name, Inches(margin_inches), Inches(margin_inches), height=Inches(height_inches))
        else:
            slide.shapes.add_picture(temp_name, Inches(margin_inches), Inches(margin_inches), width=Inches(10 - 2*margin_inches))
        os.remove(temp_name)

    bio = io.BytesIO()
    prs.save(bio)
    bio.seek(0)
    return bio.getvalue()

@app.post("/make-ppt")
async def make_ppt(images: List[UploadFile] = File(...), filename: str = Form(default="presentation.pptx")):
    if not images:
        raise HTTPException(status_code=400, detail="No images uploaded.")
    ppt_bytes = build_ppt_from_uploads(images)
    return StreamingResponse(
        io.BytesIO(ppt_bytes),
        media_type="application/vnd.openxmlformats-officedocument.presentationml.presentation",
        headers={"Content-Disposition": f'attachment; filename="{filename}"'}
    )

@app.get("/")
def root():
    return {"status": "ok", "usage": "POST /make-ppt with form-data: images=[files...] and optional filename"}