import os
import subprocess
from pathlib import Path
import json
import logging
from datetime import datetime
import shutil

# ANSI color codes
class Colors:
    PURPLE = '\033[95m'
    BLUE = '\033[94m'
    GREEN = '\033[92m'
    YELLOW = '\033[93m'
    RED = '\033[91m'
    ENDC = '\033[0m'

def get_gpu_selection():
    while True:
        print(f"\n{Colors.BLUE}Select GPU slot:{Colors.ENDC}")
        print("0 - First GPU")
        print("1 - Second GPU")
        print("2 - Third GPU")
        gpu = input(f"{Colors.YELLOW}Enter GPU number (0-2):{Colors.ENDC} ").strip()
        if gpu in ['0', '1', '2']:
            return gpu
        print(f"{Colors.RED}Invalid selection. Please try again.{Colors.ENDC}")

# Custom file handler that silently handles I/O errors (for network shares)
class SafeFileHandler(logging.FileHandler):
    """File handler that silently handles I/O errors during flush"""
    def flush(self):
        """Override flush to silently handle I/O errors"""
        try:
            super().flush()
        except (OSError, IOError):
            # Silently ignore I/O errors (network share issues)
            pass
        except Exception:
            # Silently ignore all other errors during flush
            pass
    
    def emit(self, record):
        """Override emit to handle errors gracefully"""
        try:
            super().emit(record)
        except (OSError, IOError):
            # Silently ignore I/O errors - we'll fall back to console output
            self.handleError(record)
        except Exception:
            # Handle other errors
            self.handleError(record)
    
    def handleError(self, record):
        """Override to prevent error messages from being printed"""
        # Don't print "--- Logging error ---" messages
        pass

# Set up logging
log_dir = "logs"
os.makedirs(log_dir, exist_ok=True)
log_file = os.path.join(log_dir, f"encode_{datetime.now().strftime('%Y%m%d_%H%M%S')}.log")

# Configure logging with custom handler that handles network share errors
handler = SafeFileHandler(log_file, mode='w', encoding='utf-8')
handler.setLevel(logging.INFO)
formatter = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
handler.setFormatter(formatter)

logger = logging.getLogger()
logger.setLevel(logging.INFO)
logger.addHandler(handler)
# Remove default handlers to avoid duplicate output
logger.handlers = [handler]

def get_file_info(input_file):
    cmd = [
        'ffprobe',
        '-v', 'error',
        '-show_entries', 'format=duration,size:stream=codec_name,width,height,r_frame_rate,channels,channel_layout',
        '-of', 'json',
        input_file
    ]
    result = subprocess.run(cmd, capture_output=True, text=True)
    return json.loads(result.stdout)

def get_audio_labels(input_file):
    cmd = [
        'ffprobe',
        '-v', 'error',
        '-select_streams', 'a',
        '-show_entries', 'stream=index:stream_tags=title',
        '-of', 'json',
        input_file
    ]
    result = subprocess.run(cmd, capture_output=True, text=True)
    info = json.loads(result.stdout)
    labels = []
    for stream in info.get('streams', []):
        title = stream.get('tags', {}).get('title', None)
        labels.append(title)
    return labels

def format_size(size_bytes):
    for unit in ['B', 'KB', 'MB', 'GB']:
        if size_bytes < 1024:
            return f"{size_bytes:.2f} {unit}"
        size_bytes /= 1024
    return f"{size_bytes:.2f} TB"

def safe_log_info(message, print_msg=None):
    """Safely log info message, ensuring console output even if logging fails"""
    try:
        logging.info(message)
    except (OSError, IOError) as e:
        # Logging failed (likely network share issue) - print to console
        if print_msg is None:
            print(f"{Colors.YELLOW}[Logging failed: {e}] {message}{Colors.ENDC}")
        else:
            print(print_msg)
            print(f"{Colors.YELLOW}[Logging failed: {e}]{Colors.ENDC}")
        return
    except Exception as e:
        # Other logging errors
        if print_msg is None:
            print(f"{Colors.YELLOW}[Logging error: {e}] {message}{Colors.ENDC}")
        else:
            print(print_msg)
            print(f"{Colors.YELLOW}[Logging error: {e}]{Colors.ENDC}")
        return
    
    # Always print to console if message provided
    if print_msg is not None:
        print(print_msg)

def safe_log_error(message, print_msg=None):
    """Safely log error message, ensuring console output even if logging fails"""
    try:
        logging.error(message)
    except (OSError, IOError) as e:
        # Logging failed (likely network share issue) - print to console
        if print_msg is None:
            print(f"{Colors.RED}[Logging failed: {e}] {message}{Colors.ENDC}")
        else:
            print(print_msg)
            print(f"{Colors.RED}[Logging failed: {e}]{Colors.ENDC}")
        return
    except Exception as e:
        # Other logging errors
        if print_msg is None:
            print(f"{Colors.RED}[Logging error: {e}] {message}{Colors.ENDC}")
        else:
            print(print_msg)
            print(f"{Colors.RED}[Logging error: {e}]{Colors.ENDC}")
        return
    
    # Always print to console if message provided
    if print_msg is not None:
        print(print_msg)
    else:
        print(f"{Colors.RED}{message}{Colors.ENDC}")

def encode_dvr(input_file, output_dir, gpu):
    input_path = Path(input_file)
    output_path = Path(output_dir) / f"{input_path.stem}{input_path.suffix}"

    # Get file info for logging
    file_info = get_file_info(str(input_path))
    input_size = int(file_info['format']['size'])
    duration = float(file_info['format']['duration'])
    
    safe_log_info(f"Processing file: {input_path}")
    safe_log_info(f"Input size: {format_size(input_size)}")
    safe_log_info(f"Duration: {duration:.2f} seconds")
    
    print(f"\n{Colors.BLUE}Processing file: {input_path}{Colors.ENDC}")
    print(f"Input size: {format_size(input_size)}")
    print(f"Duration: {duration:.2f} seconds")
    
    # Log stream information
    for i, stream in enumerate(file_info.get('streams', [])):
        stream_type = 'Video' if stream.get('codec_name', '').startswith('h') else 'Audio'
        safe_log_info(f"Stream {i} ({stream_type}):")
        for key, value in stream.items():
            safe_log_info(f"  {key}: {value}")

    # Skip if output file already exists
    if output_path.exists():
        output_size = output_path.stat().st_size
        safe_log_info(f"Skipping {input_path} - output already exists: {output_path}")
        safe_log_info(f"Output size: {format_size(output_size)}")
        print(f"{Colors.YELLOW}Skipping {input_path} - output already exists{Colors.ENDC}")
        return

    # Get audio labels
    audio_labels = get_audio_labels(str(input_path))
    safe_log_info(f"Audio labels: {audio_labels}")

    # FFmpeg command with NVIDIA HEVC encoder and maximum quality
    cmd = [
        'ffmpeg',
        '-v', 'verbose',  # Enable verbose output
        '-i', str(input_path),
        '-c:v', 'hevc_nvenc',
        '-gpu', gpu,
        '-preset', 'p7',
        '-tune', 'hq',
        '-rc', 'vbr',  # Variable bitrate mode
        '-rc-lookahead', '32',  # Increase lookahead for better VBR decisions
        '-spatial-aq', '1',  # Enable spatial AQ for better quality
        '-aq-strength', '15',  # Maximum allowed AQ strength
        '-cq', '30',
        '-b:v', '0',  # Let VBR determine bitrate
        '-c:a', 'copy',
        '-map', '0',
    ]
    # Add metadata for each audio stream if label exists
    for idx, label in enumerate(audio_labels):
        if label:
            cmd += [f'-metadata:s:a:{idx}', f'title={label}']
    cmd.append(str(output_path))

    try:
        # Run FFmpeg and capture output
        process = subprocess.Popen(
            cmd,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            universal_newlines=True
        )
        
        # Log FFmpeg output in real-time
        while True:
            try:
                output = process.stderr.readline()
                if output == '' and process.poll() is not None:
                    break
                if output:
                    text = output.strip()
                    if text.startswith('frame=') or ' fps=' in text:
                        safe_log_info(f"Progress: {text}", f"{Colors.PURPLE}Progress: {text}{Colors.ENDC}")
                    else:
                        safe_log_info(f"FFmpeg: {text}", f"{Colors.GREEN}FFmpeg: {text}{Colors.ENDC}")
            except (OSError, IOError) as e:
                # I/O error reading from pipe - log it
                safe_log_error(f"I/O error reading FFmpeg output: {e}")
                break
            except Exception as e:
                # Unexpected error
                safe_log_error(f"Unexpected error processing FFmpeg output: {e}")

        if process.returncode == 0:
            # Get output file info
            output_info = get_file_info(str(output_path))
            output_size = int(output_info['format']['size'])
            compression_ratio = input_size / output_size if output_size > 0 else 0
            
            safe_log_info(f"Successfully encoded: {output_path}", f"{Colors.GREEN}Successfully encoded: {output_path}{Colors.ENDC}")
            safe_log_info(f"Output size: {format_size(output_size)}")
            safe_log_info(f"Compression ratio: {compression_ratio:.2f}x", f"Compression ratio: {compression_ratio:.2f}x")
        else:
            # Convert Windows error code to signed integer if needed
            return_code = process.returncode
            if return_code > 2147483647:  # If it's a large unsigned int, convert to signed
                return_code = return_code - 4294967296
            safe_log_error(f"FFmpeg process failed with return code {return_code}", 
                          f"{Colors.RED}FFmpeg process failed with return code {return_code}{Colors.ENDC}")
            
    except subprocess.CalledProcessError as e:
        safe_log_error(f"Error encoding {input_path}: {e}", f"{Colors.RED}Error encoding {input_path}: {e}{Colors.ENDC}")
    except Exception as e:
        safe_log_error(f"Unexpected error encoding {input_path}: {type(e).__name__}: {e}", 
                      f"{Colors.RED}Unexpected error encoding {input_path}: {e}{Colors.ENDC}")

if __name__ == "__main__":
    # Get GPU selection
    gpu = get_gpu_selection()
    safe_log_info(f"Selected GPU: {gpu}")
    
    input_dir = "input"
    output_dir = "output"
    os.makedirs(output_dir, exist_ok=True)
    
    # Get list of files to process
    files = [f for f in os.listdir(input_dir) if f.endswith(('.mp4', '.DVR.mp4'))]
    total_files = len(files)
    
    if total_files == 0:
        safe_log_info("No files to process in input directory", f"{Colors.YELLOW}No files to process in input directory{Colors.ENDC}")
    else:
        safe_log_info(f"Found {total_files} files to process", f"{Colors.BLUE}Found {total_files} files to process{Colors.ENDC}")
        
        for i, file in enumerate(files, 1):
            input_file = os.path.join(input_dir, file)
            safe_log_info(f"Processing file {i}/{total_files}: {file}")
            print(f"\n{Colors.BLUE}Processing file {i}/{total_files}: {file}{Colors.ENDC}")
            encode_dvr(input_file, output_dir, gpu)