cost-model/pkg/mcp/server.go

package mcp

import (
	"context"
	"crypto/rand"
	"encoding/hex"
	"fmt"
	"strings"
	"time"

	"github.com/go-playground/validator/v10"

	"github.com/opencost/opencost/core/pkg/filter"
	"github.com/opencost/opencost/core/pkg/filter/allocation"
	cloudcostfilter "github.com/opencost/opencost/core/pkg/filter/cloudcost"
	"github.com/opencost/opencost/core/pkg/opencost"
	models "github.com/opencost/opencost/pkg/cloud/models"
	"github.com/opencost/opencost/pkg/cloudcost"
	"github.com/opencost/opencost/pkg/costmodel"
)

// QueryType defines the type of query to be executed.
type QueryType string

const (
	AllocationQueryType QueryType = "allocation"
	AssetQueryType      QueryType = "asset"
	CloudCostQueryType  QueryType = "cloudcost"
)

// MCPRequest represents a single turn in a conversation with the OpenCost MCP server.
type MCPRequest struct {
	SessionID string                `json:"sessionId"`
	Query     *OpenCostQueryRequest `json:"query"`
}

// MCPResponse is the response from the OpenCost MCP server for a single turn.
type MCPResponse struct {
	Data      interface{}   `json:"data"`
	QueryInfo QueryMetadata `json:"queryInfo"`
}

// QueryMetadata contains metadata about the query execution.
type QueryMetadata struct {
	QueryID        string        `json:"queryId"`
	Timestamp      time.Time     `json:"timestamp"`
	ProcessingTime time.Duration `json:"processingTime"`
}

// OpenCostQueryRequest provides a unified interface for all OpenCost query types.
type OpenCostQueryRequest struct {
	QueryType QueryType `json:"queryType" validate:"required,oneof=allocation asset cloudcost"`

	Window string `json:"window" validate:"required"`

	AllocationParams *AllocationQuery `json:"allocationParams,omitempty"`
	AssetParams      *AssetQuery      `json:"assetParams,omitempty"`
	CloudCostParams  *CloudCostQuery  `json:"cloudCostParams,omitempty"`
}

// AllocationQuery contains the parameters for an allocation query.
type AllocationQuery struct {
	Step                                  time.Duration `json:"step,omitempty"`
	Accumulate                            bool          `json:"accumulate,omitempty"`
	ShareIdle                             bool          `json:"shareIdle,omitempty"`
	Aggregate                             string        `json:"aggregate,omitempty"`
	IncludeIdle                           bool          `json:"includeIdle,omitempty"`
	IdleByNode                            bool          `json:"idleByNode,omitempty"`
	IncludeProportionalAssetResourceCosts bool          `json:"includeProportionalAssetResourceCosts,omitempty"`
	IncludeAggregatedMetadata             bool          `json:"includeAggregatedMetadata,omitempty"`
	ShareLB                               bool          `json:"sharelb,omitempty"`
	Filter                                string        `json:"filter,omitempty"` // Filter expression for allocations (e.g., "cluster:production", "namespace:kube-system")
}

// AssetQuery contains the parameters for an asset query.
type AssetQuery struct {
	// Currently no specific parameters needed for asset queries as it only takes window as parameter
}

// CloudCostQuery contains the parameters for a cloud cost query.
type CloudCostQuery struct {
	Aggregate  string `json:"aggregate,omitempty"`  // Comma-separated list of aggregation properties
	Accumulate string `json:"accumulate,omitempty"` // e.g., "week", "day", "month"
	Filter     string `json:"filter,omitempty"`     // Filter expression for cloud costs
	Provider   string `json:"provider,omitempty"`   // Cloud provider filter (aws, gcp, azure, etc.)
	Service    string `json:"service,omitempty"`    // Service filter (ec2, s3, compute, etc.)
	Category   string `json:"category,omitempty"`   // Category filter (compute, storage, network, etc.)
	Region     string `json:"region,omitempty"`     // Region filter
	// Additional explicit fields for filtering
	AccountID       string            `json:"accountID,omitempty"`       // Alias of Account; maps to accountID
	InvoiceEntityID string            `json:"invoiceEntityID,omitempty"` // Invoice entity ID filter
	ProviderID      string            `json:"providerID,omitempty"`      // Cloud provider resource ID filter
	Labels          map[string]string `json:"labels,omitempty"`          // Label filters (key->value)
}

// AllocationResponse represents the allocation data returned to the AI agent.
type AllocationResponse struct {
	// The allocation data, as a map of allocation sets.
	Allocations map[string]*AllocationSet `json:"allocations"`
}

// AllocationSet represents a set of allocation data.
type AllocationSet struct {
	// The name of the allocation set.
	Name        string            `json:"name"`
	Properties  map[string]string `json:"properties"`
	Allocations []*Allocation     `json:"allocations"`
}

// TotalCost calculates the total cost of all allocations in the set.
func (as *AllocationSet) TotalCost() float64 {
	var total float64
	for _, alloc := range as.Allocations {
		total += alloc.TotalCost
	}
	return total
}

// Allocation represents a single allocation data point.

type Allocation struct {
	Name string `json:"name"` // Allocation key (namespace, cluster, etc.)

	CPUCost      float64 `json:"cpuCost"`      // Cost of CPU usage
	GPUCost      float64 `json:"gpuCost"`      // Cost of GPU usage
	RAMCost      float64 `json:"ramCost"`      // Cost of memory usage
	PVCost       float64 `json:"pvCost"`       // Cost of persistent volumes
	NetworkCost  float64 `json:"networkCost"`  // Cost of network usage
	SharedCost   float64 `json:"sharedCost"`   // Shared/unallocated costs assigned here
	ExternalCost float64 `json:"externalCost"` // External costs (cloud services, etc.)
	TotalCost    float64 `json:"totalCost"`    // Sum of all costs above

	CPUCoreHours float64 `json:"cpuCoreHours"` // Usage metrics: CPU core-hours
	RAMByteHours float64 `json:"ramByteHours"` // Usage metrics: RAM byte-hours
	GPUHours     float64 `json:"gpuHours"`     // Usage metrics: GPU-hours
	PVByteHours  float64 `json:"pvByteHours"`  // Usage metrics: PV byte-hours

	Start time.Time `json:"start"` // Start timestamp for this allocation
	End   time.Time `json:"end"`   // End timestamp for this allocation
}

// AssetResponse represents the asset data returned to the AI agent.
type AssetResponse struct {
	// The asset data, as a map of asset sets.
	Assets map[string]*AssetSet `json:"assets"`
}

// AssetSet represents a set of asset data.
type AssetSet struct {
	// The name of the asset set.
	Name string `json:"name"`

	// The asset data for the set.
	Assets []*Asset `json:"assets"`
}

// Asset represents a single asset data point.
type Asset struct {
	Type       string            `json:"type"`
	Properties AssetProperties   `json:"properties"`
	Labels     map[string]string `json:"labels,omitempty"`

	Start time.Time `json:"start"`
	End   time.Time `json:"end"`

	Minutes    float64 `json:"minutes"`
	Adjustment float64 `json:"adjustment"`
	TotalCost  float64 `json:"totalCost"`

	// Disk-specific fields
	ByteHours      float64  `json:"byteHours,omitempty"`
	ByteHoursUsed  *float64 `json:"byteHoursUsed,omitempty"`
	ByteUsageMax   *float64 `json:"byteUsageMax,omitempty"`
	StorageClass   string   `json:"storageClass,omitempty"`
	VolumeName     string   `json:"volumeName,omitempty"`
	ClaimName      string   `json:"claimName,omitempty"`
	ClaimNamespace string   `json:"claimNamespace,omitempty"`
	Local          float64  `json:"local,omitempty"`

	// Node-specific fields
	NodeType     string  `json:"nodeType,omitempty"`
	CPUCoreHours float64 `json:"cpuCoreHours,omitempty"`
	RAMByteHours float64 `json:"ramByteHours,omitempty"`
	GPUHours     float64 `json:"gpuHours,omitempty"`
	GPUCount     float64 `json:"gpuCount,omitempty"`
	CPUCost      float64 `json:"cpuCost,omitempty"`
	GPUCost      float64 `json:"gpuCost,omitempty"`
	RAMCost      float64 `json:"ramCost,omitempty"`
	Discount     float64 `json:"discount,omitempty"`
	Preemptible  float64 `json:"preemptible,omitempty"`

	// Breakdown fields (can be used for different types)
	Breakdown    *AssetBreakdown `json:"breakdown,omitempty"`
	CPUBreakdown *AssetBreakdown `json:"cpuBreakdown,omitempty"`
	RAMBreakdown *AssetBreakdown `json:"ramBreakdown,omitempty"`

	// Overhead (Node-specific)
	Overhead *NodeOverhead `json:"overhead,omitempty"`

	// LoadBalancer-specific fields
	Private bool   `json:"private,omitempty"`
	Ip      string `json:"ip,omitempty"`

	// Cloud-specific fields
	Credit float64 `json:"credit,omitempty"`
}

// NodeOverhead represents node overhead information
type NodeOverhead struct {
	RamOverheadFraction  float64 `json:"ramOverheadFraction"`
	CpuOverheadFraction  float64 `json:"cpuOverheadFraction"`
	OverheadCostFraction float64 `json:"overheadCostFraction"`
}
type AssetProperties struct {
	Category   string `json:"category,omitempty"`
	Provider   string `json:"provider,omitempty"`
	Account    string `json:"account,omitempty"`
	Project    string `json:"project,omitempty"`
	Service    string `json:"service,omitempty"`
	Cluster    string `json:"cluster,omitempty"`
	Name       string `json:"name,omitempty"`
	ProviderID string `json:"providerID,omitempty"`
}

type AssetBreakdown struct {
	Idle   float64 `json:"idle"`
	Other  float64 `json:"other"`
	System float64 `json:"system"`
	User   float64 `json:"user"`
}

// CloudCostResponse represents the cloud cost data returned to the AI agent.
type CloudCostResponse struct {
	// The cloud cost data, as a map of cloud cost sets.
	CloudCosts map[string]*CloudCostSet `json:"cloudCosts"`
	// Summary information
	Summary *CloudCostSummary `json:"summary,omitempty"`
}

// CloudCostSummary provides summary information about cloud costs
type CloudCostSummary struct {
	TotalNetCost       float64            `json:"totalNetCost"`
	TotalAmortizedCost float64            `json:"totalAmortizedCost"`
	TotalInvoicedCost  float64            `json:"totalInvoicedCost"`
	KubernetesPercent  float64            `json:"kubernetesPercent"`
	ProviderBreakdown  map[string]float64 `json:"providerBreakdown,omitempty"`
	ServiceBreakdown   map[string]float64 `json:"serviceBreakdown,omitempty"`
	RegionBreakdown    map[string]float64 `json:"regionBreakdown,omitempty"`
}

// CloudCostSet represents a set of cloud cost data.
type CloudCostSet struct {
	// The name of the cloud cost set.
	Name string `json:"name"`

	// The cloud cost data for the set.
	CloudCosts []*CloudCost `json:"cloudCosts"`

	// Aggregation information
	AggregationProperties []string `json:"aggregationProperties,omitempty"`

	// Time window
	Window *TimeWindow `json:"window,omitempty"`
}

// TimeWindow represents a time range
type TimeWindow struct {
	Start time.Time `json:"start"`
	End   time.Time `json:"end"`
}

// CloudCostProperties defines the properties of a cloud cost item.
type CloudCostProperties struct {
	ProviderID        string            `json:"providerID,omitempty"`
	Provider          string            `json:"provider,omitempty"`
	AccountID         string            `json:"accountID,omitempty"`
	AccountName       string            `json:"accountName,omitempty"`
	InvoiceEntityID   string            `json:"invoiceEntityID,omitempty"`
	InvoiceEntityName string            `json:"invoiceEntityName,omitempty"`
	RegionID          string            `json:"regionID,omitempty"`
	AvailabilityZone  string            `json:"availabilityZone,omitempty"`
	Service           string            `json:"service,omitempty"`
	Category          string            `json:"category,omitempty"`
	Labels            map[string]string `json:"labels,omitempty"`
}

// CloudCost represents a single cloud cost data point.
type CloudCost struct {
	Properties       CloudCostProperties `json:"properties"`
	Window           TimeWindow          `json:"window"`
	ListCost         CostMetric          `json:"listCost"`
	NetCost          CostMetric          `json:"netCost"`
	AmortizedNetCost CostMetric          `json:"amortizedNetCost"`
	InvoicedCost     CostMetric          `json:"invoicedCost"`
	AmortizedCost    CostMetric          `json:"amortizedCost"`
}

// CostMetric represents a cost value with Kubernetes percentage
type CostMetric struct {
	Cost              float64 `json:"cost"`
	KubernetesPercent float64 `json:"kubernetesPercent"`
}

// MCPServer holds the dependencies for the MCP API server.
type MCPServer struct {
	costModel    *costmodel.CostModel
	provider     models.Provider
	cloudQuerier cloudcost.Querier
}

// NewMCPServer creates a new MCP Server.
func NewMCPServer(costModel *costmodel.CostModel, provider models.Provider, cloudQuerier cloudcost.Querier) *MCPServer {
	return &MCPServer{
		costModel:    costModel,
		provider:     provider,
		cloudQuerier: cloudQuerier,
	}
}

// ProcessMCPRequest processes an MCP request and returns an MCP response.

func (s *MCPServer) ProcessMCPRequest(request *MCPRequest) (*MCPResponse, error) {
	// 1. Validate Request
	if err := validate.Struct(request); err != nil {
		return nil, fmt.Errorf("validation failed: %w", err)
	}

	// 2. Query Dispatching
	var data interface{}
	var err error

	queryStart := time.Now()

	switch request.Query.QueryType {
	case AllocationQueryType:
		data, err = s.QueryAllocations(request.Query)
	case AssetQueryType:
		data, err = s.QueryAssets(request.Query)
	case CloudCostQueryType:
		data, err = s.QueryCloudCosts(request.Query)
	default:
		return nil, fmt.Errorf("unsupported query type: %s", request.Query.QueryType)
	}

	if err != nil {
		// Handle error appropriately, maybe return a JSON-RPC error response
		return nil, err
	}

	processingTime := time.Since(queryStart)

	// 3. Construct Final Response
	mcpResponse := &MCPResponse{
		Data: data,
		QueryInfo: QueryMetadata{
			QueryID:        generateQueryID(),
			Timestamp:      time.Now(),
			ProcessingTime: processingTime,
		},
	}
	return mcpResponse, nil
}

// validate is the singleton validator instance.
var validate = validator.New()

func generateQueryID() string {
	bytes := make([]byte, 8) // 16 hex characters
	if _, err := rand.Read(bytes); err != nil {
		// Fallback to timestamp-based ID if crypto/rand fails
		return fmt.Sprintf("query-%d", time.Now().UnixNano())
	}
	return fmt.Sprintf("query-%s", hex.EncodeToString(bytes))
}

func (s *MCPServer) QueryAllocations(query *OpenCostQueryRequest) (*AllocationResponse, error) {
	// 1. Parse Window
	window, err := opencost.ParseWindowWithOffset(query.Window, 0) // 0 offset for UTC
	if err != nil {
		return nil, fmt.Errorf("failed to parse window '%s': %w", query.Window, err)
	}

	// 2. Set default parameters
	var step time.Duration
	var aggregateBy []string
	var includeIdle, idleByNode, includeProportionalAssetResourceCosts, includeAggregatedMetadata, sharedLoadBalancer, shareIdle bool
	var accumulateBy opencost.AccumulateOption
	var filterString string

	// 3. Parse allocation parameters if provided
	if query.AllocationParams != nil {
		// Set step duration (default to window duration if not specified)
		if query.AllocationParams.Step > 0 {
			step = query.AllocationParams.Step
		} else {
			step = window.Duration()
		}

		// Parse aggregation properties
		if query.AllocationParams.Aggregate != "" {
			aggregateBy = strings.Split(query.AllocationParams.Aggregate, ",")
		}

		// Set boolean parameters
		includeIdle = query.AllocationParams.IncludeIdle
		idleByNode = query.AllocationParams.IdleByNode
		includeProportionalAssetResourceCosts = query.AllocationParams.IncludeProportionalAssetResourceCosts
		includeAggregatedMetadata = query.AllocationParams.IncludeAggregatedMetadata
		sharedLoadBalancer = query.AllocationParams.ShareLB
		shareIdle = query.AllocationParams.ShareIdle

		// Set filter string
		filterString = query.AllocationParams.Filter

		// Validate filter string if provided
		if filterString != "" {
			parser := allocation.NewAllocationFilterParser()
			_, err := parser.Parse(filterString)
			if err != nil {
				return nil, fmt.Errorf("invalid allocation filter '%s': %w", filterString, err)
			}
		}

		// Set accumulation option
		if query.AllocationParams.Accumulate {
			accumulateBy = opencost.AccumulateOptionAll
		} else {
			accumulateBy = opencost.AccumulateOptionNone
		}
	} else {
		// Default values when no parameters provided
		step = window.Duration()
		accumulateBy = opencost.AccumulateOptionNone
		filterString = ""
	}

	// 4. Call the existing QueryAllocation function with all parameters
	asr, err := s.costModel.QueryAllocation(
		window,
		step,
		aggregateBy,
		includeIdle,
		idleByNode,
		includeProportionalAssetResourceCosts,
		includeAggregatedMetadata,
		sharedLoadBalancer,
		accumulateBy,
		shareIdle,
		filterString,
	)
	if err != nil {
		return nil, fmt.Errorf("failed to query allocations: %w", err)
	}

	// 5. Handle the AllocationSetRange result
	if asr == nil || len(asr.Allocations) == 0 {
		return &AllocationResponse{
			Allocations: make(map[string]*AllocationSet),
		}, nil
	}

	// 6. Transform the result to MCP format
	// If we have multiple sets, we'll combine them or return the first one
	// For now, let's return the first allocation set
	firstSet := asr.Allocations[0]
	return transformAllocationSet(firstSet), nil
}

// transformAllocationSet converts an opencost.AllocationSet into the MCP's AllocationResponse format.
func transformAllocationSet(allocSet *opencost.AllocationSet) *AllocationResponse {
	if allocSet == nil {
		return &AllocationResponse{Allocations: make(map[string]*AllocationSet)}
	}

	mcpAllocations := make(map[string]*AllocationSet)

	// Create a single set for all allocations
	mcpSet := &AllocationSet{
		Name:        "allocations",
		Allocations: []*Allocation{},
	}

	// Convert each allocation
	for _, alloc := range allocSet.Allocations {
		if alloc == nil {
			continue
		}

		mcpAlloc := &Allocation{
			Name:         alloc.Name,
			CPUCost:      alloc.CPUCost,
			GPUCost:      alloc.GPUCost,
			RAMCost:      alloc.RAMCost,
			PVCost:       alloc.PVCost(), // Call the method
			NetworkCost:  alloc.NetworkCost,
			SharedCost:   alloc.SharedCost,
			ExternalCost: alloc.ExternalCost,
			TotalCost:    alloc.TotalCost(),
			CPUCoreHours: alloc.CPUCoreHours,
			RAMByteHours: alloc.RAMByteHours,
			GPUHours:     alloc.GPUHours,
			PVByteHours:  alloc.PVBytes(), // Use the method directly
			Start:        alloc.Start,
			End:          alloc.End,
		}
		mcpSet.Allocations = append(mcpSet.Allocations, mcpAlloc)
	}

	mcpAllocations["allocations"] = mcpSet

	return &AllocationResponse{
		Allocations: mcpAllocations,
	}
}

func (s *MCPServer) QueryAssets(query *OpenCostQueryRequest) (*AssetResponse, error) {
	// 1. Parse Window
	window, err := opencost.ParseWindowWithOffset(query.Window, 0) // 0 offset for UTC
	if err != nil {
		return nil, fmt.Errorf("failed to parse window '%s': %w", query.Window, err)
	}

	// 2. Set Query Options
	start := *window.Start()
	end := *window.End()

	// 3. Call CostModel to get the asset set
	assetSet, err := s.costModel.ComputeAssets(start, end)
	if err != nil {
		return nil, fmt.Errorf("failed to compute assets: %w", err)
	}

	// 4. Transform Response for the MCP API
	return transformAssetSet(assetSet), nil
}

// transformAssetSet converts a opencost.AssetSet into the MCP's AssetResponse format.
func transformAssetSet(assetSet *opencost.AssetSet) *AssetResponse {
	if assetSet == nil {
		return &AssetResponse{Assets: make(map[string]*AssetSet)}
	}

	mcpAssets := make(map[string]*AssetSet)

	// Create a single set for all assets
	mcpSet := &AssetSet{
		Name:   "assets",
		Assets: []*Asset{},
	}

	for _, asset := range assetSet.Assets {
		if asset == nil {
			continue
		}

		properties := asset.GetProperties()
		labels := asset.GetLabels()

		mcpAsset := &Asset{
			Type: asset.Type().String(),
			Properties: AssetProperties{
				Category:   properties.Category,
				Provider:   properties.Provider,
				Account:    properties.Account,
				Project:    properties.Project,
				Service:    properties.Service,
				Cluster:    properties.Cluster,
				Name:       properties.Name,
				ProviderID: properties.ProviderID,
			},
			Labels:     labels,
			Start:      asset.GetStart(),
			End:        asset.GetEnd(),
			Minutes:    asset.Minutes(),
			Adjustment: asset.GetAdjustment(),
			TotalCost:  asset.TotalCost(),
		}

		// Handle type-specific fields
		switch a := asset.(type) {
		case *opencost.Disk:
			mcpAsset.ByteHours = a.ByteHours
			mcpAsset.ByteHoursUsed = a.ByteHoursUsed
			mcpAsset.ByteUsageMax = a.ByteUsageMax
			mcpAsset.StorageClass = a.StorageClass
			mcpAsset.VolumeName = a.VolumeName
			mcpAsset.ClaimName = a.ClaimName
			mcpAsset.ClaimNamespace = a.ClaimNamespace
			mcpAsset.Local = a.Local
			if a.Breakdown != nil {
				mcpAsset.Breakdown = &AssetBreakdown{
					Idle:   a.Breakdown.Idle,
					Other:  a.Breakdown.Other,
					System: a.Breakdown.System,
					User:   a.Breakdown.User,
				}
			}
		case *opencost.Node:
			mcpAsset.NodeType = a.NodeType
			mcpAsset.CPUCoreHours = a.CPUCoreHours
			mcpAsset.RAMByteHours = a.RAMByteHours
			mcpAsset.GPUHours = a.GPUHours
			mcpAsset.GPUCount = a.GPUCount
			mcpAsset.CPUCost = a.CPUCost
			mcpAsset.GPUCost = a.GPUCost
			mcpAsset.RAMCost = a.RAMCost
			mcpAsset.Discount = a.Discount
			mcpAsset.Preemptible = a.Preemptible
			if a.CPUBreakdown != nil {
				mcpAsset.CPUBreakdown = &AssetBreakdown{
					Idle:   a.CPUBreakdown.Idle,
					Other:  a.CPUBreakdown.Other,
					System: a.CPUBreakdown.System,
					User:   a.CPUBreakdown.User,
				}
			}
			if a.RAMBreakdown != nil {
				mcpAsset.RAMBreakdown = &AssetBreakdown{
					Idle:   a.RAMBreakdown.Idle,
					Other:  a.RAMBreakdown.Other,
					System: a.RAMBreakdown.System,
					User:   a.RAMBreakdown.User,
				}
			}
			if a.Overhead != nil {
				mcpAsset.Overhead = &NodeOverhead{
					RamOverheadFraction:  a.Overhead.RamOverheadFraction,
					CpuOverheadFraction:  a.Overhead.CpuOverheadFraction,
					OverheadCostFraction: a.Overhead.OverheadCostFraction,
				}
			}
		case *opencost.LoadBalancer:
			mcpAsset.Private = a.Private
			mcpAsset.Ip = a.Ip
		case *opencost.Network:
			// Network assets have no specific fields beyond the base asset structure
			// All relevant data is in Properties, Labels, Cost, etc.
		case *opencost.Cloud:
			mcpAsset.Credit = a.Credit
		case *opencost.ClusterManagement:
			// ClusterManagement assets have no specific fields beyond the base asset structure
			// All relevant data is in Properties, Labels, Cost, etc.
		}

		mcpSet.Assets = append(mcpSet.Assets, mcpAsset)
	}

	mcpAssets["assets"] = mcpSet

	return &AssetResponse{
		Assets: mcpAssets,
	}
}

// QueryCloudCosts translates an MCP query into a CloudCost repository query and transforms the result.
func (s *MCPServer) QueryCloudCosts(query *OpenCostQueryRequest) (*CloudCostResponse, error) {
	// 1. Check if cloud cost querier is available
	if s.cloudQuerier == nil {
		return nil, fmt.Errorf("cloud cost querier not configured - check cloud-integration.json file")
	}

	// 2. Parse Window
	window, err := opencost.ParseWindowWithOffset(query.Window, 0) // 0 offset for UTC
	if err != nil {
		return nil, fmt.Errorf("failed to parse window '%s': %w", query.Window, err)
	}

	// 3. Build query request
	request := cloudcost.QueryRequest{
		Start:  *window.Start(),
		End:    *window.End(),
		Filter: nil, // Will be set from CloudCostParams if provided
	}

	// 4. Apply filtering and aggregation from CloudCostParams
	if query.CloudCostParams != nil {
		request = s.buildCloudCostQueryRequest(request, query.CloudCostParams)
	}

	// 5. Query the repository (this handles multiple cloud providers automatically)
	ccsr, err := s.cloudQuerier.Query(context.TODO(), request)
	if err != nil {
		return nil, fmt.Errorf("failed to query cloud costs: %w", err)
	}

	// 6. Transform Response
	return transformCloudCostSetRange(ccsr), nil
}

// buildCloudCostQueryRequest builds a QueryRequest from CloudCostParams
func (s *MCPServer) buildCloudCostQueryRequest(request cloudcost.QueryRequest, params *CloudCostQuery) cloudcost.QueryRequest {
	// Set aggregation
	if params.Aggregate != "" {
		aggregateBy := strings.Split(params.Aggregate, ",")
		request.AggregateBy = aggregateBy
	}

	// Set accumulation
	if params.Accumulate != "" {
		request.Accumulate = opencost.ParseAccumulate(params.Accumulate)
	}

	// Build filter from individual parameters or filter string
	var filter filter.Filter
	var err error

	if params.Filter != "" {
		// Parse the filter string directly
		parser := cloudcostfilter.NewCloudCostFilterParser()
		filter, err = parser.Parse(params.Filter)
		if err != nil {
			// Log error but continue without filter rather than failing the entire request
			fmt.Printf("Warning: failed to parse filter string '%s': %v\n", params.Filter, err)
		}
	} else {
		// Build filter from individual parameters
		filter = s.buildFilterFromParams(params)
	}

	request.Filter = filter
	return request
}

// buildFilterFromParams creates a filter from individual CloudCostQuery parameters
func (s *MCPServer) buildFilterFromParams(params *CloudCostQuery) filter.Filter {
	var filterParts []string

	// Add provider filter
	if params.Provider != "" {
		filterParts = append(filterParts, fmt.Sprintf(`provider:"%s"`, params.Provider))
	}

	// Add providerID filter
	if params.ProviderID != "" {
		filterParts = append(filterParts, fmt.Sprintf(`providerID:"%s"`, params.ProviderID))
	}

	// Add service filter
	if params.Service != "" {
		filterParts = append(filterParts, fmt.Sprintf(`service:"%s"`, params.Service))
	}

	// Add category filter
	if params.Category != "" {
		filterParts = append(filterParts, fmt.Sprintf(`category:"%s"`, params.Category))
	}

	// Region is intentionally not supported here

	// Add account filter (maps to accountID)
	if params.AccountID != "" {
		filterParts = append(filterParts, fmt.Sprintf(`accountID:"%s"`, params.AccountID))
	}

	// Add invoiceEntityID filter
	if params.InvoiceEntityID != "" {
		filterParts = append(filterParts, fmt.Sprintf(`invoiceEntityID:"%s"`, params.InvoiceEntityID))
	}

	// Add label filters (label[key]:"value")
	if len(params.Labels) > 0 {
		for k, v := range params.Labels {
			if k == "" {
				continue
			}
			filterParts = append(filterParts, fmt.Sprintf(`label[%s]:"%s"`, k, v))
		}
	}

	// If no filters specified, return nil
	if len(filterParts) == 0 {
		return nil
	}

	// Combine all filter parts with AND logic (parser expects 'and')
	filterString := strings.Join(filterParts, " and ")

	// Parse the combined filter string
	parser := cloudcostfilter.NewCloudCostFilterParser()
	filter, err := parser.Parse(filterString)
	if err != nil {
		// Log error but return nil rather than failing
		fmt.Printf("Warning: failed to parse combined filter '%s': %v\n", filterString, err)
		return nil
	}

	return filter
}

// transformCloudCostSetRange converts a opencost.CloudCostSetRange into the MCP's CloudCostResponse format.
func transformCloudCostSetRange(ccsr *opencost.CloudCostSetRange) *CloudCostResponse {
	if ccsr == nil || len(ccsr.CloudCostSets) == 0 {
		return &CloudCostResponse{
			CloudCosts: make(map[string]*CloudCostSet),
			Summary: &CloudCostSummary{
				TotalNetCost: 0,
			},
		}
	}

	mcpCloudCosts := make(map[string]*CloudCostSet)
	var totalNetCost, totalAmortizedCost, totalInvoicedCost float64
	providerBreakdown := make(map[string]float64)
	serviceBreakdown := make(map[string]float64)
	regionBreakdown := make(map[string]float64)

	// Process each cloud cost set in the range
	for i, ccSet := range ccsr.CloudCostSets {
		if ccSet == nil {
			continue
		}

		setName := fmt.Sprintf("cloudcosts_%d", i)
		mcpSet := &CloudCostSet{
			Name:                  setName,
			CloudCosts:            []*CloudCost{},
			AggregationProperties: ccSet.AggregationProperties,
			Window: &TimeWindow{
				Start: *ccSet.Window.Start(),
				End:   *ccSet.Window.End(),
			},
		}

		// Convert each cloud cost item
		for _, item := range ccSet.CloudCosts {
			if item == nil {
				continue
			}

			mcpCC := &CloudCost{
				Properties: CloudCostProperties{
					ProviderID:        item.Properties.ProviderID,
					Provider:          item.Properties.Provider,
					AccountID:         item.Properties.AccountID,
					AccountName:       item.Properties.AccountName,
					InvoiceEntityID:   item.Properties.InvoiceEntityID,
					InvoiceEntityName: item.Properties.InvoiceEntityName,
					RegionID:          item.Properties.RegionID,
					AvailabilityZone:  item.Properties.AvailabilityZone,
					Service:           item.Properties.Service,
					Category:          item.Properties.Category,
					Labels:            item.Properties.Labels,
				},
				Window: TimeWindow{
					Start: *item.Window.Start(),
					End:   *item.Window.End(),
				},
				ListCost: CostMetric{
					Cost:              item.ListCost.Cost,
					KubernetesPercent: item.ListCost.KubernetesPercent,
				},
				NetCost: CostMetric{
					Cost:              item.NetCost.Cost,
					KubernetesPercent: item.NetCost.KubernetesPercent,
				},
				AmortizedNetCost: CostMetric{
					Cost:              item.AmortizedNetCost.Cost,
					KubernetesPercent: item.AmortizedNetCost.KubernetesPercent,
				},
				InvoicedCost: CostMetric{
					Cost:              item.InvoicedCost.Cost,
					KubernetesPercent: item.InvoicedCost.KubernetesPercent,
				},
				AmortizedCost: CostMetric{
					Cost:              item.AmortizedCost.Cost,
					KubernetesPercent: item.AmortizedCost.KubernetesPercent,
				},
			}
			mcpSet.CloudCosts = append(mcpSet.CloudCosts, mcpCC)

			// Update summary totals
			totalNetCost += item.NetCost.Cost
			totalAmortizedCost += item.AmortizedNetCost.Cost
			totalInvoicedCost += item.InvoicedCost.Cost

			// Update breakdowns
			providerBreakdown[item.Properties.Provider] += item.NetCost.Cost
			serviceBreakdown[item.Properties.Service] += item.NetCost.Cost
			regionBreakdown[item.Properties.RegionID] += item.NetCost.Cost
		}

		mcpCloudCosts[setName] = mcpSet
	}

	// Calculate cost-weighted average Kubernetes percentage (by NetCost)
	var avgKubernetesPercent float64
	var numerator, denominator float64
	for _, ccSet := range ccsr.CloudCostSets {
		for _, item := range ccSet.CloudCosts {
			if item == nil {
				continue
			}
			cost := item.NetCost.Cost
			percent := item.NetCost.KubernetesPercent
			if cost <= 0 {
				continue
			}
			numerator += cost * percent
			denominator += cost
		}
	}
	if denominator > 0 {
		avgKubernetesPercent = numerator / denominator
	}

	summary := &CloudCostSummary{
		TotalNetCost:       totalNetCost,
		TotalAmortizedCost: totalAmortizedCost,
		TotalInvoicedCost:  totalInvoicedCost,
		KubernetesPercent:  avgKubernetesPercent,
		ProviderBreakdown:  providerBreakdown,
		ServiceBreakdown:   serviceBreakdown,
		RegionBreakdown:    regionBreakdown,
	}

	return &CloudCostResponse{
		CloudCosts: mcpCloudCosts,
		Summary:    summary,
	}
}