class PipelineError(Exception):
    """Base class for pipeline failures. `stage` and `message` are shown to the
    user directly; the original exception (if any) is kept for logs only."""

    def __init__(self, stage: str, message: str, cause: Exception | None = None):
        self.stage = stage
        self.message = message
        self.cause = cause
        super().__init__(f"[{stage}] {message}")


class AudioExtractionError(PipelineError):
    def __init__(self, message: str, cause: Exception | None = None):
        super().__init__("audio_extraction", message, cause)


class TranscriptionError(PipelineError):
    def __init__(self, message: str, cause: Exception | None = None):
        super().__init__("transcription", message, cause)


class DiarizationError(PipelineError):
    def __init__(self, message: str, cause: Exception | None = None):
        super().__init__("diarization", message, cause)


class SummarizationError(PipelineError):
    def __init__(self, message: str, cause: Exception | None = None):
        super().__init__("summarization", message, cause)