"""Instance schemas for API serialization."""

from datetime import datetime
from typing import Optional
from uuid import UUID

from pydantic import BaseModel, ConfigDict, Field


class InstanceCreate(BaseModel):
    """Schema for creating a new instance."""

    instance_id: str = Field(
        ...,
        min_length=1,
        max_length=255,
        description="Unique instance identifier (e.g., 'acme-orchestrator')",
    )
    region: Optional[str] = Field(None, max_length=50, description="Deployment region")
    license_expires_at: Optional[datetime] = Field(
        None,
        description="License expiry date (None = perpetual)",
    )


class InstanceResponse(BaseModel):
    """Schema for instance API responses.

    Note: license_key and hub_api_key are ONLY returned on creation.
    """

    model_config = ConfigDict(from_attributes=True)

    id: UUID
    instance_id: str
    client_id: UUID

    # License info
    license_key: Optional[str] = Field(
        None,
        description="ONLY returned on creation - store securely!",
    )
    license_key_prefix: str
    license_status: str
    license_issued_at: datetime
    license_expires_at: Optional[datetime]

    # Hub API key
    hub_api_key: Optional[str] = Field(
        None,
        description="ONLY returned on creation - store securely!",
    )

    # Activation state
    activated_at: Optional[datetime]
    last_activation_at: Optional[datetime]
    activation_count: int

    # Metadata
    region: Optional[str]
    version: Optional[str]
    last_seen_at: Optional[datetime]
    status: str

    created_at: datetime
    updated_at: datetime


class InstanceBriefResponse(BaseModel):
    """Brief instance response for listings (no secrets)."""

    model_config = ConfigDict(from_attributes=True)

    id: UUID
    instance_id: str
    client_id: UUID
    license_key_prefix: str
    license_status: str
    license_expires_at: Optional[datetime]
    activated_at: Optional[datetime]
    activation_count: int
    region: Optional[str]
    status: str
    created_at: datetime


# === ACTIVATION SCHEMAS ===


class ActivationRequest(BaseModel):
    """
    Activation request from a client instance.

    PRIVACY: This schema ONLY accepts:
    - license_key (credential for validation)
    - instance_id (identifier)

    It NEVER accepts sensitive data fields.
    """

    license_key: str = Field(..., description="License key (lb_inst_...)")
    instance_id: str = Field(..., description="Instance identifier")


class ActivationResponse(BaseModel):
    """Response to a successful activation."""

    status: str = Field("ok", description="Activation status")
    instance_id: str
    hub_api_key: str = Field(
        ...,
        description="API key for telemetry auth (or 'USE_EXISTING')",
    )
    config: dict = Field(
        default_factory=dict,
        description="Optional configuration from Hub",
    )


class ActivationError(BaseModel):
    """Error response for failed activation."""

    error: str = Field(..., description="Human-readable error message")
    code: str = Field(
        ...,
        description="Error code: invalid_license, expired, suspended, instance_not_found",
    )