"""
Internal data models for the chunker pipeline.

These are pipeline-internal dataclasses, not schema models.
Schema-level ChunkJob is in core/schema/models/jobs.py.

Demonstrates: Core data structures (Interview Topic 5).
"""

from dataclasses import dataclass, field
from typing import Any, Dict, List, Optional


@dataclass
class Chunk:
    """A time-based segment of the source media file."""

    sequence: int
    start_time: float  # seconds
    end_time: float  # seconds
    source_path: str  # path to source file
    duration: float  # end_time - start_time
    checksum: str = ""  # computed after extraction


@dataclass
class ChunkResult:
    """Result of processing a single chunk."""

    sequence: int
    success: bool
    checksum_valid: bool = True
    processing_time: float = 0.0
    error: Optional[str] = None
    retries: int = 0
    worker_id: Optional[str] = None
    output_file: Optional[str] = None


@dataclass
class PipelineResult:
    """Aggregate result of the entire pipeline run."""

    total_chunks: int = 0
    processed: int = 0
    failed: int = 0
    retries: int = 0
    elapsed_time: float = 0.0
    throughput_mbps: float = 0.0
    worker_stats: Dict[str, Any] = field(default_factory=dict)
    errors: List[str] = field(default_factory=list)
    chunks_in_order: bool = True
    output_dir: Optional[str] = None
    chunk_files: List[str] = field(default_factory=list)