"""Common schemas used across the API."""

from pydantic import BaseModel, Field


class ErrorDetail(BaseModel):
    """Individual error detail for validation errors."""

    loc: list[str | int] = Field(description="Location of the error (field path)")
    msg: str = Field(description="Error message")
    type: str = Field(description="Error type identifier")


class ErrorResponse(BaseModel):
    """Structured error response returned by all error handlers."""

    error: str = Field(description="Error type (e.g., 'not_found', 'validation_error')")
    message: str = Field(description="Human-readable error message")
    details: list[ErrorDetail] | None = Field(
        default=None, description="Additional error details for validation errors"
    )
    request_id: str | None = Field(
        default=None, description="Request trace ID for debugging"
    )

    model_config = {
        "json_schema_extra": {
            "examples": [
                {
                    "error": "not_found",
                    "message": "Incident not found",
                    "request_id": "abc123def456",
                },
                {
                    "error": "validation_error",
                    "message": "Request validation failed",
                    "details": [
                        {"loc": ["body", "title"], "msg": "Field required", "type": "missing"}
                    ],
                    "request_id": "abc123def456",
                },
            ]
        }
    }


class CursorParams(BaseModel):
    """Pagination parameters using cursor-based pagination."""

    cursor: str | None = Field(default=None, description="Cursor for pagination")
    limit: int = Field(default=20, ge=1, le=100, description="Number of items per page")


class PaginatedResponse[T](BaseModel):
    """Generic paginated response wrapper."""

    items: list[T]
    next_cursor: str | None = Field(
        default=None, description="Cursor for next page, null if no more items"
    )
    has_more: bool = Field(description="Whether there are more items")