package scenarios

import (
	"github.com/damirmukimov/city_resource_graph/models"
	"github.com/damirmukimov/city_resource_graph/models/params"
)

// ScenarioResult contains the results of a scenario analysis.
type ScenarioResult struct {
	Name        string              `json:"name"`
	Description string              `json:"description"`
	Parameters  ScenarioParams      `json:"parameters"`
	Result      *models.ModelResult `json:"result"`
	KeyMetrics  KeyMetrics          `json:"key_metrics"`
}

// ScenarioParams describes the parameter changes for a scenario.
type ScenarioParams struct {
	AdoptionMultiplier float64 `json:"adoption_multiplier"` // Multiplier for adoption rates
	PricingMultiplier  float64 `json:"pricing_multiplier"`  // Multiplier for pricing
	CostMultiplier     float64 `json:"cost_multiplier"`     // Multiplier for costs
}

// KeyMetrics contains the most important metrics for comparison.
type KeyMetrics struct {
	TotalRevenue   float64 `json:"total_revenue"`
	TotalCosts     float64 `json:"total_costs"`
	TotalProfit    float64 `json:"total_profit"`
	NPV            float64 `json:"npv"`
	IRR            float64 `json:"irr"`
	PaybackYears   float64 `json:"payback_years"`
	Year3Customers int     `json:"year3_customers"`
	Year3Revenue   float64 `json:"year3_revenue"`
}

// RunSensitivityAnalysis runs multiple scenarios with parameter variations.
func RunSensitivityAnalysis(baseParams *params.Params) []ScenarioResult {
	scenarios := []ScenarioResult{
		{
			Name:        "Base Case",
			Description: "Original parameters as configured",
			Parameters: ScenarioParams{
				AdoptionMultiplier: 1.0,
				PricingMultiplier:  1.0,
				CostMultiplier:     1.0,
			},
		},
		{
			Name:        "Optimistic",
			Description: "20% higher adoption, 10% higher pricing, 10% lower costs",
			Parameters: ScenarioParams{
				AdoptionMultiplier: 1.2,
				PricingMultiplier:  1.1,
				CostMultiplier:     0.9,
			},
		},
		{
			Name:        "Conservative",
			Description: "20% lower adoption, 10% lower pricing, 10% higher costs",
			Parameters: ScenarioParams{
				AdoptionMultiplier: 0.8,
				PricingMultiplier:  0.9,
				CostMultiplier:     1.1,
			},
		},
		{
			Name:        "High Growth",
			Description: "50% higher adoption, same pricing and costs",
			Parameters: ScenarioParams{
				AdoptionMultiplier: 1.5,
				PricingMultiplier:  1.0,
				CostMultiplier:     1.0,
			},
		},
		{
			Name:        "Cost Focused",
			Description: "Same adoption and pricing, 20% lower costs",
			Parameters: ScenarioParams{
				AdoptionMultiplier: 1.0,
				PricingMultiplier:  1.0,
				CostMultiplier:     0.8,
			},
		},
	}

	results := make([]ScenarioResult, len(scenarios))

	for i, scenario := range scenarios {
		// Create modified parameters for this scenario
		scenarioParams := createScenarioParams(baseParams, scenario.Parameters)

		// Run the model with modified parameters
		result, err := models.Calculate(scenarioParams)
		if err != nil {
			// In a real implementation, you'd want to handle errors better
			continue
		}

		// Extract key metrics
		keyMetrics := extractKeyMetrics(result)

		results[i] = ScenarioResult{
			Name:        scenario.Name,
			Description: scenario.Description,
			Parameters:  scenario.Parameters,
			Result:      result,
			KeyMetrics:  keyMetrics,
		}
	}

	return results
}

// createScenarioParams creates modified parameters for a scenario.
func createScenarioParams(base *params.Params, mods ScenarioParams) *params.Params {
	// Create a deep copy of the base parameters
	// For simplicity, we'll modify the key fields directly
	// In a production system, you'd want proper deep copying

	scenario := *base // Shallow copy

	// Modify adoption rates
	if mods.AdoptionMultiplier != 1.0 {
		for yearStr, original := range base.Adoption.TotalOrgs {
			scenario.Adoption.TotalOrgs[yearStr] = int(float64(original) * mods.AdoptionMultiplier)
		}
	}

	// Modify pricing
	if mods.PricingMultiplier != 1.0 {
		scenario.Pricing.Basic = base.Pricing.Basic * mods.PricingMultiplier
		scenario.Pricing.Business = base.Pricing.Business * mods.PricingMultiplier
		scenario.Pricing.Enterprise = base.Pricing.Enterprise * mods.PricingMultiplier
	}

	// Modify costs
	if mods.CostMultiplier != 1.0 {
		for yearStr, engineers := range base.Costs.Engineers {
			scenario.Costs.Engineers[yearStr] = int(float64(engineers) * mods.CostMultiplier)
		}
		for yearStr, infra := range base.Costs.Infrastructure {
			scenario.Costs.Infrastructure[yearStr] = infra * mods.CostMultiplier
		}
		for yearStr, marketing := range base.Costs.MarketingSales {
			scenario.Costs.MarketingSales[yearStr] = marketing * mods.CostMultiplier
		}
		for yearStr, ops := range base.Costs.Operations {
			scenario.Costs.Operations[yearStr] = ops * mods.CostMultiplier
		}
	}

	return &scenario
}

// extractKeyMetrics pulls the most important metrics from a model result.
func extractKeyMetrics(result *models.ModelResult) KeyMetrics {
	year3 := result.Years[len(result.Years)-1] // Last year (Year 3)

	return KeyMetrics{
		TotalRevenue:   result.Summary.TotalRevenue,
		TotalCosts:     result.Summary.TotalCosts,
		TotalProfit:    result.Summary.TotalProfit,
		NPV:            result.Profitability.NPV,
		IRR:            result.Profitability.IRR,
		PaybackYears:   result.Profitability.PaybackPeriod,
		Year3Customers: year3.Customer.TotalOrgs,
		Year3Revenue:   year3.Revenue.Total,
	}
}