backend/models.py

"""
Pydantic request/response models for the Health Insurance AI Copilot API.
"""

from pydantic import BaseModel, Field
from typing import List, Optional
from datetime import datetime


# ── Request Models ─────────────────────────────────────────────────────────────

class ChatRequest(BaseModel):
    session_id: str = Field(..., description="Unique session identifier (UUID)")
    query: str = Field(..., min_length=1, max_length=2000, description="User question")
    plan_tier: Optional[str] = Field(None, description="User's selected plan tier")


class ClearSessionRequest(BaseModel):
    session_id: str


# ── Response Models ────────────────────────────────────────────────────────────

class ChatMessage(BaseModel):
    role: str           # "human" or "ai"
    content: str
    timestamp: Optional[str] = None


class ChatResponse(BaseModel):
    session_id: str
    query: str
    answer: str
    intent: str              # SIMPLE_LOOKUP | POLICY_QUESTION | MULTI_HOP | COMPARISON
    steps_log: List[str]
    memories_used: List[str] = []   # Facts Mem0 extracted and stored from this turn
    timestamp: str
    run_id: Optional[str] = None         # LangSmith trace run ID (None if tracing disabled)
    confidence: Optional[str] = None    # HIGH | MEDIUM | LOW | BLOCKED (new confidence scorer)
    confidence_reason: Optional[str] = None  # Human-readable confidence explanation
    blocked: bool = False                # True if query_guard blocked the query
    sub_questions: List[str] = []       # Sub-questions from query_decomposer (MULTI_HOP)


class SessionHistoryResponse(BaseModel):
    session_id: str
    history: List[ChatMessage]
    message_count: int


class ComponentHealth(BaseModel):
    status: str         # "ok" | "error" | "not_checked"
    detail: Optional[str] = None


class HealthResponse(BaseModel):
    status: str         # "healthy" | "degraded" | "unhealthy"
    timestamp: str
    version: str = "1.0.0"
    components: dict
    active_sessions: int


class ErrorResponse(BaseModel):
    error: str
    detail: Optional[str] = None
    session_id: Optional[str] = None


# ── Workflow / Trace Models ──────────────────────────────────────────────────

class WorkflowStep(BaseModel):
    step_id: str
    name: str
    description: str
    status: str = "completed"
    output_summary: Optional[str] = None


class WorkflowTraceResponse(BaseModel):
    session_id: str
    query: str
    intent: str
    steps: List[WorkflowStep]
    full_trace: List[str]
    retrieved_context_preview: str

class WorkflowDiagramResponse(BaseModel):
    session_id: str
    query: str
    intent: str
    diagram: str
    steps_log: List[str] | None = None


# ── Memory Models ─────────────────────────────────────────────────────────────

class MemoryFact(BaseModel):
    id: Optional[str] = None
    memory: str
    created_at: Optional[str] = None


class MemoryResponse(BaseModel):
    session_id: str
    memory_count: int
    facts: List[MemoryFact]
    note: str = "In-memory only — resets on server restart"