app/api/v1/schemas.py

"""
Pydantic schemas for API request/response models.
"""

from pydantic import BaseModel, Field, validator


class SummarizeRequest(BaseModel):
    """Request schema for text summarization."""

    text: str = Field(
        ..., min_length=1, max_length=32000, description="Text to summarize"
    )
    max_tokens: int | None = Field(
        default=256, ge=1, le=2048, description="Maximum tokens for summary"
    )
    temperature: float | None = Field(
        default=0.3, ge=0.0, le=2.0, description="Sampling temperature for generation"
    )
    top_p: float | None = Field(
        default=0.9, ge=0.0, le=1.0, description="Nucleus sampling parameter"
    )
    prompt: str | None = Field(
        default="Summarize the key points concisely:",
        max_length=500,
        description="Custom prompt for summarization",
    )

    @validator("text")
    def validate_text(cls, v):
        """Validate text input."""
        if not v.strip():
            raise ValueError("Text cannot be empty or only whitespace")
        return v.strip()


class SummarizeResponse(BaseModel):
    """Response schema for text summarization."""

    summary: str = Field(..., description="Generated summary")
    model: str = Field(..., description="Model used for summarization")
    tokens_used: int | None = Field(None, description="Number of tokens used")
    latency_ms: float | None = Field(
        None, description="Processing time in milliseconds"
    )


class HealthResponse(BaseModel):
    """Response schema for health check."""

    status: str = Field(..., description="Service status")
    service: str = Field(..., description="Service name")
    version: str = Field(..., description="Service version")
    ollama: str | None = Field(None, description="Ollama service status")


class StreamChunk(BaseModel):
    """Schema for streaming response chunks."""

    content: str = Field(..., description="Content chunk from the stream")
    done: bool = Field(..., description="Whether this is the final chunk")
    tokens_used: int | None = Field(None, description="Number of tokens used so far")


class ErrorResponse(BaseModel):
    """Error response schema."""

    detail: str = Field(..., description="Error message")
    code: str | None = Field(None, description="Error code")
    request_id: str | None = Field(None, description="Request ID for tracking")