from fastapi import FastAPI, UploadFile, File, HTTPException
from fastapi.responses import FileResponse, JSONResponse
from fastapi.middleware.cors import CORSMiddleware
import os
import uuid
import shutil

app = FastAPI()

# Configure CORS
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Allows all origins
    allow_credentials=True,
    allow_methods=["*"],  # Allows all methods
    allow_headers=["*"],  # Allows all headers
)

UPLOAD_DIRECTORY = "./uploads"

os.makedirs(UPLOAD_DIRECTORY, exist_ok=True)

def format_bytes(bytes_value):
    """Convert bytes to human readable format"""
    for unit in ['B', 'KB', 'MB', 'GB', 'TB']:
        if bytes_value < 1024.0:
            return f"{bytes_value:.2f} {unit}"
        bytes_value /= 1024.0
    return f"{bytes_value:.2f} PB"

def check_disk_space():
    """Check disk space on startup and log the information"""
    try:
        # Get disk usage for the current directory
        total, used, free = shutil.disk_usage(".")
        
        # Calculate usage percentage
        usage_percentage = (used / total) * 100 if total > 0 else 0
        
        print("=" * 50)
        print("DISK SPACE CHECK ON STARTUP")
        print("=" * 50)
        print(f"Total space: {format_bytes(total)}")
        print(f"Used space: {format_bytes(used)}")
        print(f"Free space: {format_bytes(free)}")
        print(f"Usage percentage: {usage_percentage:.2f}%")
        print(f"Upload directory: {os.path.abspath(UPLOAD_DIRECTORY)}")
        print(f"Upload directory exists: {os.path.exists(UPLOAD_DIRECTORY)}")
        
        # Warning if disk space is low
        if usage_percentage > 90:
            print("⚠️  WARNING: Disk space is critically low!")
        elif usage_percentage > 80:
            print("⚠️  WARNING: Disk space is getting low!")
        else:
            print("✅ Disk space is adequate")
        
        print("=" * 50)
        
    except Exception as e:
        print(f"❌ Failed to check disk space: {str(e)}")

@app.on_event("startup")
async def startup_event():
    """Run startup tasks"""
    check_disk_space()

@app.post("/upload")
async def upload_mp4(file: UploadFile = File(...)):
    if not file.filename.endswith(".mp4"):
        raise HTTPException(status_code=400, detail="Invalid file type. Only MP4 files are allowed.")

    file_id = str(uuid.uuid4()) + ".mp4"
    file_path = os.path.join(UPLOAD_DIRECTORY, file_id)

    try:
        with open(file_path, "wb") as buffer:
            while True:
                chunk = await file.read(1024 * 1024)  # Read in 1MB chunks
                if not chunk:
                    break
                buffer.write(chunk)
        return JSONResponse(content={"id": file_id, "message": "File uploaded successfully"}, status_code=200)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Failed to upload file: {str(e)}")

@app.get("/download/{mp4_id}")
async def download_mp4(mp4_id: str):
    file_path = os.path.join(UPLOAD_DIRECTORY, mp4_id)
    if not os.path.exists(file_path):
        raise HTTPException(status_code=404, detail="File not found")
    return FileResponse(file_path, media_type="video/mp4", filename=mp4_id)

@app.delete("/delete/{mp4_id}")
async def delete_mp4(mp4_id: str):
    file_path = os.path.join(UPLOAD_DIRECTORY, mp4_id)
    if not os.path.exists(file_path):
        raise HTTPException(status_code=404, detail="File not found")
    try:
        os.remove(file_path)
        return JSONResponse(content={"message": f"File {mp4_id} deleted successfully"}, status_code=200)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Failed to delete file: {str(e)}")