from fastapi import FastAPI, HTTPException, UploadFile, File, Form
import subprocess
import base64
import os
import uuid
import shutil

app = FastAPI()

@app.get("/")
def greet_json():
    return {"status": "online", "engine": "Viral Cat Local Processor"}

def file_to_base64(filepath):
    if not os.path.exists(filepath): return None
    with open(filepath, "rb") as f:
        return base64.b64encode(f.read()).decode('utf-8')

@app.post("/process-video")
async def process_video(
    file: UploadFile = File(...), 
    fps: int = Form(2), 
    is_pro: bool = Form(False)
):
    job_id = str(uuid.uuid4())
    work_dir = f"/tmp/viralcat_{job_id}"
    os.makedirs(work_dir, exist_ok=True)
    
    video_path = os.path.join(work_dir, "video.mp4")
    audio_path = os.path.join(work_dir, "audio.mp3")
    
    try:
        # 1. Save the uploaded file locally
        with open(video_path, "wb") as buffer:
            shutil.copyfileobj(file.file, buffer)

        # 2. Check Duration (120s limit for free)
        probe = subprocess.run([
            "ffprobe", "-v", "error", "-show_entries", 
            "format=duration", "-of", "default=noprint_wrappers=1:nokey=1", 
            video_path
        ], capture_output=True, text=True, check=True)
        
        duration = float(probe.stdout.strip() or 0)
        if duration > 120 and not is_pro:
            raise ValueError(f"Video ({duration:.1f}s) exceeds 120s limit.")

        # 3. Extract Frames (2 per second)
        subprocess.run([
            "ffmpeg", "-y", "-i", video_path, 
            "-vf", f"fps={fps}", 
            "-q:v", "4", f"{work_dir}/frame_%04d.jpg"
        ], check=True, capture_output=True)

        # 4. Extract Audio
        subprocess.run([
            "ffmpeg", "-y", "-i", video_path, 
            "-q:a", "0", "-map", "a", "-ac", "1", "-b:a", "64k", audio_path
        ], check=True, capture_output=True)

        # 5. Base64 Conversion
        frame_files = sorted([f for f in os.listdir(work_dir) if f.startswith("frame_") and f.endswith(".jpg")])
        if len(frame_files) > 80: frame_files = frame_files[:80] # Safety cap

        frames_b64 =[file_to_base64(os.path.join(work_dir, f)) for f in frame_files]
        audio_b64 = file_to_base64(audio_path)
        
        print(f"Done with video, {len(frames_b64)}")
      
        return {
            "success": True,
            "total_frames": len(frames_b64),
            "duration": duration,
            "frames": frames_b64,
            "audio": audio_b64
        }

    except Exception as e:
        print(f"ERROR: {str(e)}")
        return {"success": False, "error": str(e)}
        
    finally:
        # CLEANUP
        if os.path.exists(work_dir):
            shutil.rmtree(work_dir, ignore_errors=True)