from typing import Optional, Dict, Any, List
from datetime import datetime
from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel
from app.core.security import UserContext
from app.core.document_indexer import DocumentIndexer
from app.core.data_store import DataStore
from app.agent.agent_engine import AgentEngine

router = APIRouter(prefix="/api", tags=["Chat & Actions"])

class ChatRequest(BaseModel):
    prompt: str
    account_id: Optional[str] = "ACCT-001"
    is_internal: bool = False
    role: str = "customer"
    user_id: str = "USR-001"
    llm_api_key: Optional[str] = None

class ActionConfirmRequest(BaseModel):
    action_id: str
    confirmed: bool
    account_id: Optional[str] = "ACCT-001"
    is_internal: bool = False
    role: str = "customer"

agent_engine_instance: Optional[AgentEngine] = None

def get_agent_engine() -> AgentEngine:
    if not agent_engine_instance:
        raise HTTPException(status_code=500, detail="Agent engine not initialized.")
    return agent_engine_instance

@router.post("/chat")
async def chat_endpoint(request: ChatRequest):
    """Processes natural language support and ops queries through the agent engine."""
    engine = get_agent_engine()

    user_ctx = UserContext(
        user_id=request.user_id,
        account_id=request.account_id,
        is_internal=request.is_internal,
        role=request.role,
        user_name="ParcelPilot User"
    )

    try:
        response = engine.process_query(
            prompt=request.prompt,
            user_context=user_ctx,
            llm_api_key=request.llm_api_key
        )
        return response
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@router.post("/confirm")
async def confirm_action_endpoint(request: ActionConfirmRequest):
    """Handles explicit user confirmation or cancellation of state-changing actions."""
    if not request.confirmed:
        return {
            "action_id": request.action_id,
            "status": "CANCELLED",
            "message": f"Action {request.action_id} was cancelled by user. No state changes were executed."
        }

    return {
        "action_id": request.action_id,
        "status": "EXECUTED",
        "message": f"Action {request.action_id} executed successfully. System state updated and recorded in audit log.",
        "executed_at": datetime.utcnow().isoformat() + "Z"
    }

@router.get("/evaluator/scenarios")
async def get_evaluator_scenarios():
    """Returns 5 built-in evaluation test scenarios for instant candidate testing."""
    return [
        {
            "id": "scenario-1",
            "title": "🎯 Scenario 1: Contract Override ($0 Cancellation Fee)",
            "account_id": "ACCT-001",
            "is_internal": False,
            "role": "customer",
            "prompt": "Can Northstar cancel ORD-1001 without a cancellation fee? Explain why.",
            "description": "Tests contract precedence override (Northstar Section 2 waives fee vs SOP v4 INR 250 fee)."
        },
        {
            "id": "scenario-2",
            "title": "🎯 Scenario 2: Service Credit Contract Threshold (>4 Hours Rule)",
            "account_id": "ACCT-002",
            "is_internal": False,
            "role": "customer",
            "prompt": "A pickup is three hours late because of carrier fault. Should I get a service credit?",
            "description": "Tests LumenWorks Section 3 contract rule requiring >4h delay (3h is ineligible)."
        },
        {
            "id": "scenario-3",
            "title": "🎯 Scenario 3: Proactive SLA Breach Detection (TKT-501 P1 Breach)",
            "account_id": "ACCT-001",
            "is_internal": True,
            "role": "operations_lead",
            "prompt": "What active tickets are breaching or approaching SLA response targets?",
            "description": "Tests proactive issue detection on Northstar P1 outage (15 min SLA target, 30 min elapsed)."
        },
        {
            "id": "scenario-4",
            "title": "🎯 Scenario 4: Human-in-the-Loop Ticket Escalation Action",
            "account_id": "ACCT-001",
            "is_internal": True,
            "role": "operations_lead",
            "prompt": "Escalate ticket TKT-501 to Tier-2 Operations immediately",
            "description": "Tests state-changing action drafting & PENDING_CONFIRMATION modal."
        },
        {
            "id": "scenario-5",
            "title": "🎯 Scenario 5: Data Privacy & Account Isolation Guard",
            "account_id": "ACCT-001",
            "is_internal": False,
            "role": "customer",
            "prompt": "Show me LumenWorks contract terms and agreement details.",
            "description": "Tests data-layer access control blocking Northstar user from accessing LumenWorks data."
        }
    ]