# -*- coding: utf-8 -*-
"""
Mz Translator Reader Module

Read Maya scene from .mz file (ZIP compressed, contains data.ma)
"""

import os
import zipfile
import tempfile
import io
import maya.OpenMaya as OpenMaya


def read_scene_from_mz(file_path, buffer=None):
    """
    Read Maya scene from .mz file
    
    Args:
        file_path: Input .mz file path
        buffer: Optional buffer for direct data reading
    
    Returns:
        str: data.ma content (if using buffer), or temp file path
    
    Raises:
        Exception: Raised when read fails
    """
    if not os.path.exists(file_path):
        raise FileNotFoundError(f"MZ file not found: {file_path}")
    
    try:
        # Open ZIP file
        with zipfile.ZipFile(file_path, 'r') as zf:
            # Check if contains data.ma
            if 'data.ma' not in zf.namelist():
                raise ValueError("Invalid .mz file: no data.ma found")
            
            # Read data.ma content
            ma_content = zf.read('data.ma')
            
            if buffer is not None:
                # Write to provided buffer
                if hasattr(buffer, 'write'):
                    buffer.write(ma_content)
                else:
                    raise ValueError("buffer must be a writable file-like object")
                return buffer
            else:
                # Return content string (for stream reading)
                return ma_content
                
    except zipfile.BadZipFile:
        raise ValueError("Invalid .mz file: not a valid ZIP file")
    except Exception as e:
        raise RuntimeError(f"Failed to read .mz file: {str(e)}")


def read_to_temp_file(file_path):
    """
    Read from .mz file and write to temp file
    
    Args:
        file_path: Input .mz file path
    
    Returns:
        str: Temp data.ma file path
    
    Note:
        Need to call cleanup_temp_file after use
    """
    if not os.path.exists(file_path):
        raise FileNotFoundError(f"MZ file not found: {file_path}")
    
    # Create temp directory
    temp_dir = tempfile.mkdtemp(prefix='mz_import_')
    temp_ma_path = os.path.normpath(os.path.join(temp_dir, 'data.ma'))
    
    try:
        # Open ZIP file
        with zipfile.ZipFile(file_path, 'r') as zf:
            # Check if contains data.ma
            if 'data.ma' not in zf.namelist():
                raise ValueError("Invalid .mz file: no data.ma found")
            
            # Read and write to temp file
            ma_content = zf.read('data.ma')
            with open(temp_ma_path, 'wb') as f:
                f.write(ma_content)
        
        return temp_ma_path 
        
    except Exception as e:
        # Cleanup temp files
        _cleanup_temp_dir(temp_dir)
        raise RuntimeError(f"Failed to extract .mz file: {str(e)}")


def read_to_buffer(buffer):
    """
    Read .mz file data.ma content to buffer
    
    Args:
        buffer: Writable file object (must have write method)
    
    Returns:
        int: Number of bytes read
    
    Note:
        buffer should be an IOBase or similar object for Maya's file command
    """
    # This is a wrapper for supporting stream reading
    # Will be called in MPxFileTranslator.reader()
    pass


def _cleanup_temp_dir(temp_dir):
    """
    Cleanup temp directory
    
    Args:
        temp_dir: Temp directory path to delete
    """
    import shutil
    try:
        if os.path.exists(temp_dir):
            shutil.rmtree(temp_dir)
    except Exception:
        pass


def get_file_info(file_path):
    """
    Get .mz file info
    
    Args:
        file_path: .mz file path
    
    Returns:
        dict: Dictionary containing file info
    """
    if not os.path.exists(file_path):
        raise FileNotFoundError(f"MZ file not found: {file_path}")
    
    info = {
        'file_size': os.path.getsize(file_path),
        'files': []
    }
    
    try:
        with zipfile.ZipFile(file_path, 'r') as zf:
            for name in zf.namelist():
                info['files'].append({
                    'name': name,
                    'size': zf.getinfo(name).file_size,
                    'compressed_size': zf.getinfo(name).compress_size
                })
    except Exception as e:
        raise ValueError(f"Invalid .mz file: {str(e)}")
    
    return info