src/application/dtos/processing_result_dto.py

"""Processing Result Data Transfer Object"""

from dataclasses import dataclass
from typing import Optional, Dict, Any
from datetime import datetime


@dataclass
class ProcessingResultDto:
    """DTO for pipeline output data
    
    Contains the results of processing audio through the
    STT -> Translation -> TTS pipeline.
    """
    success: bool
    original_text: Optional[str] = None
    translated_text: Optional[str] = None
    audio_path: Optional[str] = None
    processing_time: float = 0.0
    error_message: Optional[str] = None
    error_code: Optional[str] = None
    metadata: Optional[Dict[str, Any]] = None
    timestamp: Optional[datetime] = None
    
    def __post_init__(self):
        """Validate and set defaults after initialization"""
        self._validate()
        if self.metadata is None:
            self.metadata = {}
        if self.timestamp is None:
            self.timestamp = datetime.utcnow()
    
    def _validate(self):
        """Validate processing result data"""
        if not isinstance(self.success, bool):
            raise ValueError("Success must be a boolean value")
        
        if self.processing_time < 0:
            raise ValueError("Processing time cannot be negative")
        
        if self.success:
            # For successful processing, we should have some output
            if not self.original_text and not self.translated_text and not self.audio_path:
                raise ValueError("Successful processing must have at least one output (text or audio)")
        else:
            # For failed processing, we should have an error message
            if not self.error_message:
                raise ValueError("Failed processing must include an error message")
        
        # Validate error code format if provided
        if self.error_code:
            valid_error_codes = [
                'STT_ERROR', 'TRANSLATION_ERROR', 'TTS_ERROR',
                'AUDIO_FORMAT_ERROR', 'VALIDATION_ERROR', 'SYSTEM_ERROR'
            ]
            if self.error_code not in valid_error_codes:
                raise ValueError(f"Invalid error code: {self.error_code}. Valid codes: {valid_error_codes}")
        
        # Validate metadata if provided
        if self.metadata and not isinstance(self.metadata, dict):
            raise ValueError("Metadata must be a dictionary")
    
    @property
    def has_text_output(self) -> bool:
        """Check if result has text output"""
        return bool(self.original_text or self.translated_text)
    
    @property
    def has_audio_output(self) -> bool:
        """Check if result has audio output"""
        return bool(self.audio_path)
    
    @property
    def is_complete(self) -> bool:
        """Check if processing is complete (success or failure with error)"""
        return self.success or bool(self.error_message)
    
    def add_metadata(self, key: str, value: Any) -> None:
        """Add metadata entry"""
        if self.metadata is None:
            self.metadata = {}
        self.metadata[key] = value
    
    def get_metadata(self, key: str, default: Any = None) -> Any:
        """Get metadata value"""
        if self.metadata is None:
            return default
        return self.metadata.get(key, default)
    
    def to_dict(self) -> dict:
        """Convert to dictionary representation"""
        return {
            'success': self.success,
            'original_text': self.original_text,
            'translated_text': self.translated_text,
            'audio_path': self.audio_path,
            'processing_time': self.processing_time,
            'error_message': self.error_message,
            'error_code': self.error_code,
            'metadata': self.metadata or {},
            'timestamp': self.timestamp.isoformat() if self.timestamp else None,
            'has_text_output': self.has_text_output,
            'has_audio_output': self.has_audio_output,
            'is_complete': self.is_complete
        }
    
    @classmethod
    def success_result(cls, original_text: str = None, translated_text: str = None, 
                      audio_path: str = None, processing_time: float = 0.0,
                      metadata: Dict[str, Any] = None) -> 'ProcessingResultDto':
        """Create a successful processing result"""
        return cls(
            success=True,
            original_text=original_text,
            translated_text=translated_text,
            audio_path=audio_path,
            processing_time=processing_time,
            metadata=metadata
        )
    
    @classmethod
    def error_result(cls, error_message: str, error_code: str = None,
                    processing_time: float = 0.0, metadata: Dict[str, Any] = None) -> 'ProcessingResultDto':
        """Create a failed processing result"""
        return cls(
            success=False,
            error_message=error_message,
            error_code=error_code,
            processing_time=processing_time,
            metadata=metadata
        )
    
    @classmethod
    def from_dict(cls, data: dict) -> 'ProcessingResultDto':
        """Create instance from dictionary"""
        timestamp = None
        if data.get('timestamp'):
            timestamp = datetime.fromisoformat(data['timestamp'].replace('Z', '+00:00'))
        
        return cls(
            success=data['success'],
            original_text=data.get('original_text'),
            translated_text=data.get('translated_text'),
            audio_path=data.get('audio_path'),
            processing_time=data.get('processing_time', 0.0),
            error_message=data.get('error_message'),
            error_code=data.get('error_code'),
            metadata=data.get('metadata'),
            timestamp=timestamp
        )