from fastapi import APIRouter, Depends, HTTPException
from typing import List, Dict, Any
from app.models.goal_models import (
    ClientProfile, InvestmentGoal, GoalsDashboard,
    SIPCalculationRequest, SIPCalculationResponse,
    RequiredSIPRequest, RequiredSIPResponse, GoalsDashboardRequest
)
from app.services.sip_calculator import SIPCalculator

router = APIRouter()

@router.post("/dashboard", response_model=GoalsDashboard)
async def get_goals_dashboard(request: GoalsDashboardRequest):
    """
    Calculate goals dashboard metrics including total required SIP, shortfall/surplus
    """
    try:
        total_required_sip = sum(goal.required_sip for goal in request.goals)
        shortfall = max(0, total_required_sip - request.monthly_savings)
        surplus = max(0, request.monthly_savings - total_required_sip)
        
        return GoalsDashboard(
            goals=request.goals,
            total_required_sip=total_required_sip,
            monthly_savings=request.monthly_savings,
            shortfall=shortfall,
            surplus=surplus
        )
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error calculating goals dashboard: {str(e)}")

@router.post("/calculate-sip", response_model=SIPCalculationResponse)
async def calculate_sip(
    request: SIPCalculationRequest,
    include_yearly_breakdown: bool = False
):
    """
    Calculate SIP maturity amount based on monthly investment, expected return, and time period
    """
    try:
        calculator = SIPCalculator()
        result = calculator.get_sip_calculation(request, include_yearly_breakdown)
        return result
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error calculating SIP: {str(e)}")

@router.post("/required-sip", response_model=RequiredSIPResponse)
async def calculate_required_sip(request: RequiredSIPRequest):
    """
    Calculate required SIP amount to reach a target amount
    """
    try:
        calculator = SIPCalculator()
        result = calculator.get_required_sip(request)
        return result
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error calculating required SIP: {str(e)}")

@router.post("/inflation-adjusted")
async def calculate_inflation_adjusted_amount(
    target_amount: float,
    years: int,
    expected_inflation: float
):
    """
    Calculate inflation-adjusted target amount for a goal
    """
    try:
        inflation_adjusted_amount = target_amount * ((1 + expected_inflation/100) ** years)
        calculator = SIPCalculator()
        required_sip = calculator.calculate_required_sip(inflation_adjusted_amount, years, 12)
        
        return {
            "original_amount": target_amount,
            "inflation_adjusted_amount": inflation_adjusted_amount,
            "required_sip": required_sip,
            "years": years,
            "expected_inflation": expected_inflation
        }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error calculating inflation-adjusted amount: {str(e)}")