from fastapi import APIRouter, UploadFile, File, HTTPException
from app.core.config import settings
import shutil
import uuid
from pathlib import Path

router = APIRouter()

@router.post("/")
async def upload_material(file: UploadFile = File(...)):
    if not file.filename.lower().endswith(('.mp4', '.mov', '.avi')):
        raise HTTPException(400, "Invalid format")
    
    file_id = str(uuid.uuid4())
    ext = Path(file.filename).suffix
    save_path = settings.UPLOAD_DIR / "materials" / f"{file_id}{ext}"
    
    # Save file
    with open(save_path, "wb") as buffer:
        shutil.copyfileobj(file.file, buffer)
    
    # Calculate size
    size_mb = save_path.stat().st_size / (1024 * 1024)
        
    return {
        "id": file_id,
        "name": file.filename, 
        "path": f"uploads/materials/{file_id}{ext}",
        "size_mb": size_mb,
        "type": "video"
    }

@router.get("/")
async def list_materials():
    materials_dir = settings.UPLOAD_DIR / "materials"
    files = []
    if materials_dir.exists():
        for f in materials_dir.glob("*"):
            try:
                stat = f.stat()
                files.append({
                    "id": f.stem,
                    "name": f.name,
                    "path": f"uploads/materials/{f.name}",
                    "size_mb": stat.st_size / (1024 * 1024),
                    "type": "video",
                    "created_at": stat.st_ctime
                })
            except Exception:
                continue
    # Sort by creation time desc
    files.sort(key=lambda x: x.get("created_at", 0), reverse=True)
    return {"materials": files}