"""
Error handling utilities for VidGen
"""

import streamlit as st
import time
import functools
from typing import Any, Callable, Optional

def retry_on_error(max_retries: int = 3, delay: float = 1.0, backoff: float = 2.0):
    """Decorator to retry functions on specific errors"""
    def decorator(func: Callable) -> Callable:
        @functools.wraps(func)
        def wrapper(*args, **kwargs) -> Any:
            last_exception = None
            
            for attempt in range(max_retries):
                try:
                    return func(*args, **kwargs)
                except Exception as e:
                    last_exception = e
                    error_msg = str(e).lower()
                    
                    # Check for retryable errors
                    retryable_errors = [
                        'bodystreamBuffer was aborted',
                        'connection error',
                        'timeout',
                        'network error',
                        'temporary failure',
                        'rate limit'
                    ]
                    
                    is_retryable = any(err in error_msg for err in retryable_errors)
                    
                    if not is_retryable or attempt == max_retries - 1:
                        raise e
                    
                    wait_time = delay * (backoff ** attempt)
                    st.warning(f"⚠️ Attempt {attempt + 1} failed: {e}. Retrying in {wait_time:.1f}s...")
                    time.sleep(wait_time)
            
            raise last_exception
        return wrapper
    return decorator

def handle_stream_error(func: Callable) -> Callable:
    """Handle stream buffer errors specifically"""
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        try:
            return func(*args, **kwargs)
        except Exception as e:
            error_msg = str(e).lower()
            if 'bodystreamBuffer' in error_msg or 'aborted' in error_msg:
                st.error("🔄 Connection interrupted. Please try again.")
                st.info("💡 Tip: Try refreshing the page if the issue persists.")
                return None
            else:
                raise e
    return wrapper

class ProgressTracker:
    """Track progress with better error handling"""
    
    def __init__(self, total_jobs: int):
        self.total_jobs = total_jobs
        self.current_job = 0
        self.progress_bar = None
        self.status_text = None
        
    def start(self):
        """Initialize progress tracking"""
        self.progress_bar = st.progress(0)
        self.status_text = st.empty()
        
    def update(self, job_idx: int, status: str = "Processing..."):
        """Update progress"""
        if self.progress_bar and self.status_text:
            progress = (job_idx + 1) / self.total_jobs
            self.progress_bar.progress(progress)
            self.status_text.text(f"{status} ({job_idx + 1}/{self.total_jobs})")
            
    def complete(self):
        """Mark as complete"""
        if self.progress_bar and self.status_text:
            self.progress_bar.progress(1.0)
            self.status_text.text("✅ All jobs completed!")