package service

import (
	"bytes"
	"context"
	"crypto/rand"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"math/big"
	"net/http"
	"regexp"
	"strings"
	"text/template"
	"time"

	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/repository"
	applogger "github.com/gochat/gochat/pkg/logger"
)

// CaptainCustomToolService implements business logic for CaptainCustomTool operations.
// Reference: Chatwoot enterprise/app/controllers/api/v1/captain/custom_tools_controller.rb
type CaptainCustomToolService struct {
	toolRepo    *repository.CaptainCustomToolRepo
	accountRepo *repository.AccountRepo
	httpClient  HTTPDoer
}

const (
	maxCaptainCustomToolsPerAccount = 15
	maxCaptainCustomToolSlugLength  = 64
	customToolSlugCollisionSuffix   = 7
)

var ErrCaptainCustomToolLimitExceeded = errors.New("You can create a maximum of 15 custom tools per account")

type CaptainCustomToolValidationError struct {
	Message    string
	Attributes []string
}

func (e *CaptainCustomToolValidationError) Error() string {
	return e.Message
}

type HTTPDoer interface {
	Do(req *http.Request) (*http.Response, error)
}

// NewCaptainCustomToolService creates a new CaptainCustomToolService.
func NewCaptainCustomToolService(toolRepo *repository.CaptainCustomToolRepo, accountRepo ...*repository.AccountRepo) *CaptainCustomToolService {
	svc := &CaptainCustomToolService{toolRepo: toolRepo, httpClient: &http.Client{Timeout: 30 * time.Second}}
	if len(accountRepo) > 0 {
		svc.accountRepo = accountRepo[0]
	}
	return svc
}

func (s *CaptainCustomToolService) SetHTTPClient(client HTTPDoer) {
	if client != nil {
		s.httpClient = client
	}
}

func (s *CaptainCustomToolService) CustomToolsEnabled(ctx context.Context, accountID uint) bool {
	if s.accountRepo == nil {
		return true
	}
	account, err := s.accountRepo.FindByID(ctx, accountID)
	if err != nil {
		return false
	}
	return featureFlagStringEnabled(account.FeatureFlags, "custom_tools") || featureFlagStringEnabled(account.FeatureFlags, "captain_integration_v2")
}

// --- Request DTOs ---

// CreateCustomToolRequest is the DTO for creating a custom tool.
type CreateCustomToolRequest struct {
	Title            string          `json:"title" validate:"required"`
	Slug             string          `json:"slug"`
	Description      string          `json:"description"`
	EndpointURL      string          `json:"endpoint_url" validate:"required"`
	HTTPMethod       string          `json:"http_method"`
	AuthType         string          `json:"auth_type"`
	AuthConfig       json.RawMessage `json:"auth_config"`
	ParamSchema      json.RawMessage `json:"param_schema"`
	RequestTemplate  string          `json:"request_template"`
	ResponseTemplate string          `json:"response_template"`
}

// UpdateCustomToolRequest is the DTO for updating a custom tool.
type UpdateCustomToolRequest struct {
	Title            string          `json:"title"`
	Description      string          `json:"description"`
	EndpointURL      string          `json:"endpoint_url"`
	HTTPMethod       string          `json:"http_method"`
	AuthType         string          `json:"auth_type"`
	AuthConfig       json.RawMessage `json:"auth_config"`
	ParamSchema      json.RawMessage `json:"param_schema"`
	RequestTemplate  string          `json:"request_template"`
	ResponseTemplate string          `json:"response_template"`
	Enabled          *bool           `json:"enabled"`
}

// --- CRUD Operations ---

// Create creates a new CaptainCustomTool.
func (s *CaptainCustomToolService) Create(ctx context.Context, accountID uint, req *CreateCustomToolRequest) (*model.CaptainCustomTool, error) {
	var err error

	// Default values
	httpMethod := req.HTTPMethod
	if httpMethod == "" {
		httpMethod = "GET"
	}
	authType := req.AuthType
	if authType == "" {
		authType = "none"
	}
	slug := req.Slug
	if slug == "" {
		slug, err = s.uniqueCustomToolSlug(ctx, accountID, req.Title)
		if err != nil {
			return nil, err
		}
	}

	tool := &model.CaptainCustomTool{
		AccountID:        accountID,
		Title:            req.Title,
		Slug:             slug,
		Description:      req.Description,
		EndpointURL:      req.EndpointURL,
		HTTPMethod:       httpMethod,
		AuthType:         model.ToolAuthType(authType),
		AuthConfig:       req.AuthConfig,
		ParamSchema:      req.ParamSchema,
		RequestTemplate:  req.RequestTemplate,
		ResponseTemplate: req.ResponseTemplate,
		Enabled:          true,
	}
	if err := validateCaptainCustomTool(tool); err != nil {
		return nil, err
	}
	if req.Slug != "" && s.customToolSlugExists(ctx, accountID, req.Slug) {
		return nil, newCaptainCustomToolValidationError("Slug has already been taken", "slug")
	}
	count, err := s.toolRepo.CountByAccount(ctx, accountID)
	if err != nil {
		return nil, fmt.Errorf("count custom tools: %w", err)
	}
	if count >= maxCaptainCustomToolsPerAccount {
		return nil, ErrCaptainCustomToolLimitExceeded
	}

	if err := s.toolRepo.Create(ctx, tool); err != nil {
		applogger.L().Errorf("Create captain custom tool: %v", err)
		return nil, fmt.Errorf("create custom tool: %w", err)
	}
	return tool, nil
}

// Get retrieves a custom tool by ID.
func (s *CaptainCustomToolService) Get(ctx context.Context, id uint) (*model.CaptainCustomTool, error) {
	tool, err := s.toolRepo.GetByID(ctx, id)
	if err != nil {
		applogger.L().Errorf("Get captain custom tool: %v", err)
		return nil, fmt.Errorf("get custom tool: %w", err)
	}
	return tool, nil
}

func (s *CaptainCustomToolService) GetByAccount(ctx context.Context, accountID, id uint) (*model.CaptainCustomTool, error) {
	tool, err := s.toolRepo.GetByAccountAndID(ctx, accountID, id)
	if err != nil {
		applogger.L().Errorf("Get captain custom tool: %v", err)
		return nil, fmt.Errorf("get custom tool: %w", err)
	}
	return tool, nil
}

// Update updates an existing custom tool.
func (s *CaptainCustomToolService) Update(ctx context.Context, id uint, req *UpdateCustomToolRequest) (*model.CaptainCustomTool, error) {
	tool, err := s.toolRepo.GetByID(ctx, id)
	if err != nil {
		return nil, fmt.Errorf("custom tool not found: %w", err)
	}

	if req.Title != "" {
		tool.Title = req.Title
	}
	if req.Description != "" {
		tool.Description = req.Description
	}
	if req.EndpointURL != "" {
		tool.EndpointURL = req.EndpointURL
	}
	if req.HTTPMethod != "" {
		tool.HTTPMethod = req.HTTPMethod
	}
	if req.AuthType != "" {
		tool.AuthType = model.ToolAuthType(req.AuthType)
	}
	if len(req.AuthConfig) > 0 && string(req.AuthConfig) != "null" {
		tool.AuthConfig = req.AuthConfig
	}
	if len(req.ParamSchema) > 0 && string(req.ParamSchema) != "null" {
		tool.ParamSchema = req.ParamSchema
	}
	if req.RequestTemplate != "" {
		tool.RequestTemplate = req.RequestTemplate
	}
	if req.ResponseTemplate != "" {
		tool.ResponseTemplate = req.ResponseTemplate
	}
	if req.Enabled != nil {
		tool.Enabled = *req.Enabled
	}

	if err := s.toolRepo.Update(ctx, tool); err != nil {
		applogger.L().Errorf("Update captain custom tool: %v", err)
		return nil, fmt.Errorf("update custom tool: %w", err)
	}
	return tool, nil
}

func (s *CaptainCustomToolService) UpdateByAccount(ctx context.Context, accountID, id uint, req *UpdateCustomToolRequest) (*model.CaptainCustomTool, error) {
	tool, err := s.toolRepo.GetByAccountAndID(ctx, accountID, id)
	if err != nil {
		return nil, fmt.Errorf("custom tool not found: %w", err)
	}
	applyCustomToolUpdate(tool, req)
	if err := validateCaptainCustomTool(tool); err != nil {
		return nil, err
	}
	if err := s.toolRepo.Update(ctx, tool); err != nil {
		applogger.L().Errorf("Update captain custom tool: %v", err)
		return nil, fmt.Errorf("update custom tool: %w", err)
	}
	return tool, nil
}

// Delete deletes a custom tool by ID.
func (s *CaptainCustomToolService) Delete(ctx context.Context, id uint) error {
	if err := s.toolRepo.Delete(ctx, id); err != nil {
		applogger.L().Errorf("Delete captain custom tool: %v", err)
		return fmt.Errorf("delete custom tool: %w", err)
	}
	return nil
}

func (s *CaptainCustomToolService) DeleteByAccount(ctx context.Context, accountID, id uint) error {
	if _, err := s.toolRepo.GetByAccountAndID(ctx, accountID, id); err != nil {
		return fmt.Errorf("custom tool not found: %w", err)
	}
	if err := s.toolRepo.DeleteByAccount(ctx, accountID, id); err != nil {
		applogger.L().Errorf("Delete captain custom tool: %v", err)
		return fmt.Errorf("delete custom tool: %w", err)
	}
	return nil
}

// List retrieves custom tools for an account with pagination.
func (s *CaptainCustomToolService) List(ctx context.Context, accountID uint, offset, limit int) ([]model.CaptainCustomTool, int64, error) {
	tools, count, err := s.toolRepo.ListByAccount(ctx, accountID, offset, limit)
	if err != nil {
		applogger.L().Errorf("List captain custom tools: %v", err)
		return nil, 0, fmt.Errorf("list custom tools: %w", err)
	}
	return tools, count, nil
}

func applyCustomToolUpdate(tool *model.CaptainCustomTool, req *UpdateCustomToolRequest) {
	if req.Title != "" {
		tool.Title = req.Title
	}
	if req.Description != "" {
		tool.Description = req.Description
	}
	if req.EndpointURL != "" {
		tool.EndpointURL = req.EndpointURL
	}
	if req.HTTPMethod != "" {
		tool.HTTPMethod = req.HTTPMethod
	}
	if req.AuthType != "" {
		tool.AuthType = model.ToolAuthType(req.AuthType)
	}
	if len(req.AuthConfig) > 0 && string(req.AuthConfig) != "null" {
		tool.AuthConfig = req.AuthConfig
	}
	if len(req.ParamSchema) > 0 && string(req.ParamSchema) != "null" {
		tool.ParamSchema = req.ParamSchema
	}
	if req.RequestTemplate != "" {
		tool.RequestTemplate = req.RequestTemplate
	}
	if req.ResponseTemplate != "" {
		tool.ResponseTemplate = req.ResponseTemplate
	}
	if req.Enabled != nil {
		tool.Enabled = *req.Enabled
	}
}

func (s *CaptainCustomToolService) uniqueCustomToolSlug(ctx context.Context, accountID uint, title string) (string, error) {
	baseSlug := customToolSlug(title)
	if !s.customToolSlugExists(ctx, accountID, baseSlug) {
		return baseSlug, nil
	}

	truncated := truncateString(baseSlug, maxCaptainCustomToolSlugLength-customToolSlugCollisionSuffix)
	for i := 0; i < 5; i++ {
		candidate := truncated + "_" + randomLowerAlphanumeric(6)
		if !s.customToolSlugExists(ctx, accountID, candidate) {
			return candidate, nil
		}
	}
	return "", fmt.Errorf("slug generation failed")
}

func (s *CaptainCustomToolService) customToolSlugExists(ctx context.Context, accountID uint, slug string) bool {
	_, err := s.toolRepo.GetBySlug(ctx, accountID, slug)
	return err == nil
}

func validateCaptainCustomTool(tool *model.CaptainCustomTool) error {
	var messages []string
	var attributes []string
	add := func(attr, message string) {
		messages = append(messages, message)
		attributes = append(attributes, attr)
	}

	if strings.TrimSpace(tool.Title) == "" {
		add("title", "Title can't be blank")
	}
	if strings.TrimSpace(tool.EndpointURL) == "" {
		add("endpoint_url", "Endpoint url can't be blank")
	}
	if len(tool.Slug) > maxCaptainCustomToolSlugLength {
		add("slug", "Slug is too long (maximum is 64 characters)")
	}
	if tool.HTTPMethod != "GET" && tool.HTTPMethod != "POST" {
		add("http_method", "Http method is not included in the list")
	}
	switch tool.AuthType {
	case model.ToolAuthTypeNone, model.ToolAuthTypeBearer, model.ToolAuthTypeBasic, model.ToolAuthTypeApiKey:
	default:
		add("auth_type", "Auth type is not included in the list")
	}
	for _, validation := range validateCaptainCustomToolParamSchema(tool.ParamSchema) {
		add(validation.attribute, validation.message)
	}

	if len(messages) == 0 {
		return nil
	}
	return &CaptainCustomToolValidationError{Message: strings.Join(messages, ", "), Attributes: uniqueStrings(attributes)}
}

type customToolParamSchemaValidation struct {
	attribute string
	message   string
}

func validateCaptainCustomToolParamSchema(raw json.RawMessage) []customToolParamSchemaValidation {
	if len(raw) == 0 || string(raw) == "null" {
		return nil
	}
	var items []map[string]any
	if err := json.Unmarshal(raw, &items); err != nil {
		return []customToolParamSchemaValidation{{attribute: "param_schema", message: "Param schema must be of type array"}}
	}

	allowed := map[string]bool{"name": true, "type": true, "description": true, "required": true}
	var validations []customToolParamSchemaValidation
	for _, item := range items {
		for _, field := range []string{"name", "type", "description"} {
			value, ok := item[field]
			if !ok {
				validations = append(validations, customToolParamSchemaValidation{attribute: field, message: customToolFieldLabel(field) + " is required"})
				continue
			}
			if _, ok := value.(string); !ok {
				validations = append(validations, customToolParamSchemaValidation{attribute: field, message: customToolFieldLabel(field) + " must be of type string"})
			}
		}
		if value, ok := item["required"]; ok {
			if _, ok := value.(bool); !ok {
				validations = append(validations, customToolParamSchemaValidation{attribute: "required", message: "Required must be of type boolean"})
			}
		}
		for field := range item {
			if !allowed[field] {
				validations = append(validations, customToolParamSchemaValidation{attribute: field, message: customToolFieldLabel(field) + " is not permitted"})
			}
		}
	}
	return validations
}

func customToolFieldLabel(field string) string {
	if field == "" {
		return field
	}
	return strings.ToUpper(field[:1]) + field[1:]
}

func newCaptainCustomToolValidationError(message, attribute string) error {
	return &CaptainCustomToolValidationError{Message: message, Attributes: []string{attribute}}
}

func uniqueStrings(values []string) []string {
	seen := make(map[string]bool, len(values))
	unique := make([]string, 0, len(values))
	for _, value := range values {
		if seen[value] {
			continue
		}
		seen[value] = true
		unique = append(unique, value)
	}
	return unique
}

func customToolSlug(title string) string {
	slug := strings.ToLower(strings.TrimSpace(title))
	slug = regexp.MustCompile(`[^a-z0-9]+`).ReplaceAllString(slug, "_")
	slug = strings.Trim(slug, "_")
	return truncateString("custom_"+slug, maxCaptainCustomToolSlugLength)
}

func truncateString(value string, maxLen int) string {
	if len(value) <= maxLen {
		return value
	}
	return value[:maxLen]
}

func randomLowerAlphanumeric(length int) string {
	const alphabet = "abcdefghijklmnopqrstuvwxyz0123456789"
	var b strings.Builder
	b.Grow(length)
	for i := 0; i < length; i++ {
		n, err := rand.Int(rand.Reader, big.NewInt(int64(len(alphabet))))
		if err != nil {
			b.WriteByte(alphabet[time.Now().UnixNano()%int64(len(alphabet))])
			continue
		}
		b.WriteByte(alphabet[n.Int64()])
	}
	return b.String()
}

// --- Tool Execution ---

// ExecuteToolResult holds the result of executing a custom tool.
type ExecuteToolResult struct {
	Success bool        `json:"success"`
	Data    interface{} `json:"data"`
	Error   string      `json:"error,omitempty"`
}

type TestToolResult struct {
	Status int    `json:"status"`
	Body   string `json:"body"`
}

// ExecuteTool calls the external HTTP endpoint configured in the custom tool.
// Reference: Chatwoot Captain::CustomTool#execute
func (s *CaptainCustomToolService) ExecuteTool(ctx context.Context, id uint, params map[string]interface{}) (*ExecuteToolResult, error) {
	tool, err := s.toolRepo.GetByID(ctx, id)
	if err != nil {
		return nil, fmt.Errorf("custom tool not found: %w", err)
	}

	if !tool.Enabled {
		return nil, fmt.Errorf("custom tool is disabled")
	}

	// Build request body from template + params
	requestBody, err := buildRequestBody(tool.RequestTemplate, params)
	if err != nil {
		return nil, fmt.Errorf("build request body: %w", err)
	}

	// Create HTTP request
	method := strings.ToUpper(tool.HTTPMethod)
	var httpReq *http.Request
	if method == "GET" || method == "DELETE" {
		httpReq, err = http.NewRequestWithContext(ctx, method, tool.EndpointURL, nil)
	} else {
		httpReq, err = http.NewRequestWithContext(ctx, method, tool.EndpointURL, bytes.NewReader(requestBody))
	}
	if err != nil {
		return nil, fmt.Errorf("create HTTP request: %w", err)
	}

	// Set content type for methods with body
	if method != "GET" && method != "DELETE" {
		httpReq.Header.Set("Content-Type", "application/json")
	}

	// Apply authentication
	if err := applyAuth(httpReq, tool); err != nil {
		return nil, fmt.Errorf("apply auth: %w", err)
	}

	// Execute HTTP call
	resp, err := s.httpClient.Do(httpReq)
	if err != nil {
		applogger.L().Errorf("ExecuteTool HTTP call: %v", err)
		return &ExecuteToolResult{Success: false, Error: err.Error()}, nil
	}
	defer resp.Body.Close()

	respBody, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
	if err != nil {
		return nil, fmt.Errorf("read response: %w", err)
	}

	// Parse response through response template if defined
	var resultData interface{}
	if tool.ResponseTemplate != "" {
		parsed, err := parseResponseTemplate(tool.ResponseTemplate, respBody)
		if err != nil {
			applogger.L().Errorf("ExecuteTool parse response template: %v", err)
			resultData = string(respBody)
		} else {
			resultData = parsed
		}
	} else {
		// Try to parse as JSON; fall back to raw string
		var jsonData interface{}
		if err := json.Unmarshal(respBody, &jsonData); err == nil {
			resultData = jsonData
		} else {
			resultData = string(respBody)
		}
	}

	success := resp.StatusCode >= 200 && resp.StatusCode < 300
	return &ExecuteToolResult{
		Success: success,
		Data:    resultData,
	}, nil
}

// buildRequestBody renders the Go template with params to produce the HTTP request body.
func buildRequestBody(templateStr string, params map[string]interface{}) ([]byte, error) {
	if templateStr == "" {
		// No template — send params as JSON directly
		return json.Marshal(params)
	}

	tmpl, err := template.New("request").Parse(templateStr)
	if err != nil {
		return nil, fmt.Errorf("parse request template: %w", err)
	}

	var buf bytes.Buffer
	if err := tmpl.Execute(&buf, params); err != nil {
		return nil, fmt.Errorf("execute request template: %w", err)
	}
	return buf.Bytes(), nil
}

// parseResponseTemplate renders the response template with the raw response body.
func parseResponseTemplate(templateStr string, rawBody []byte) (interface{}, error) {
	// Parse the raw body as a map for template rendering
	var data interface{}
	if err := json.Unmarshal(rawBody, &data); err != nil {
		data = map[string]interface{}{"raw": string(rawBody)}
	}

	tmpl, err := template.New("response").Parse(templateStr)
	if err != nil {
		return nil, fmt.Errorf("parse response template: %w", err)
	}

	var buf bytes.Buffer
	if err := tmpl.Execute(&buf, data); err != nil {
		return nil, fmt.Errorf("execute response template: %w", err)
	}

	// Try to parse the rendered template output as JSON
	var result interface{}
	rendered := buf.Bytes()
	if err := json.Unmarshal(rendered, &result); err != nil {
		return string(rendered), nil
	}
	return result, nil
}

// applyAuth sets authentication headers on the HTTP request based on tool config.
func applyAuth(req *http.Request, tool *model.CaptainCustomTool) error {
	switch tool.AuthType {
	case model.ToolAuthTypeNone:
		// No auth required
		return nil
	case model.ToolAuthTypeBasic:
		var authCfg struct {
			Username string `json:"username"`
			Password string `json:"password"`
		}
		if err := json.Unmarshal(tool.AuthConfig, &authCfg); err != nil {
			return fmt.Errorf("parse basic auth config: %w", err)
		}
		req.SetBasicAuth(authCfg.Username, authCfg.Password)
		return nil
	case model.ToolAuthTypeBearer:
		var authCfg struct {
			Token string `json:"token"`
		}
		if err := json.Unmarshal(tool.AuthConfig, &authCfg); err != nil {
			return fmt.Errorf("parse bearer auth config: %w", err)
		}
		req.Header.Set("Authorization", "Bearer "+authCfg.Token)
		return nil
	case model.ToolAuthTypeApiKey:
		var authCfg struct {
			Key    string `json:"key"`
			Value  string `json:"value"`
			Header string `json:"header"` // default: "X-API-Key"
		}
		if err := json.Unmarshal(tool.AuthConfig, &authCfg); err != nil {
			return fmt.Errorf("parse api_key auth config: %w", err)
		}
		headerName := authCfg.Header
		if headerName == "" {
			headerName = "X-API-Key"
		}
		req.Header.Set(headerName, authCfg.Value)
		return nil
	default:
		return fmt.Errorf("unsupported auth type: %s", tool.AuthType)
	}
}

// --- Tool Testing ---
// Reference: Chatwoot Captain::CustomToolsController#test
// TestTool allows testing a custom tool with parameters before enabling it.
// Unlike ExecuteTool, TestTool does not require the tool to be enabled
// and returns detailed error information for debugging.

// TestToolRequest is the DTO for testing a custom tool.
type TestToolRequest struct {
	ToolID           uint                   `json:"tool_id"`
	Title            string                 `json:"title"`
	Description      string                 `json:"description"`
	EndpointURL      string                 `json:"endpoint_url"`
	HTTPMethod       string                 `json:"http_method"`
	AuthType         string                 `json:"auth_type"`
	AuthConfig       json.RawMessage        `json:"auth_config"`
	ParamSchema      json.RawMessage        `json:"param_schema"`
	RequestTemplate  string                 `json:"request_template"`
	ResponseTemplate string                 `json:"response_template"`
	Params           map[string]interface{} `json:"params"`
}

// TestTool tests a custom tool with given parameters without requiring it to be enabled.
func (s *CaptainCustomToolService) TestTool(ctx context.Context, accountID uint, req *TestToolRequest) (*TestToolResult, error) {
	tool := &model.CaptainCustomTool{
		AccountID:        accountID,
		Title:            req.Title,
		Description:      req.Description,
		EndpointURL:      req.EndpointURL,
		HTTPMethod:       req.HTTPMethod,
		AuthType:         model.ToolAuthType(req.AuthType),
		AuthConfig:       req.AuthConfig,
		ParamSchema:      req.ParamSchema,
		RequestTemplate:  req.RequestTemplate,
		ResponseTemplate: req.ResponseTemplate,
		Enabled:          true,
	}
	if req.ToolID != 0 {
		stored, err := s.toolRepo.GetByID(ctx, req.ToolID)
		if err != nil {
			return nil, fmt.Errorf("custom tool not found: %w", err)
		}
		if stored.AccountID != accountID {
			return nil, fmt.Errorf("custom tool does not belong to this account")
		}
		tool = stored
	}
	if tool.EndpointURL == "" {
		return nil, fmt.Errorf("endpoint_url is required")
	}
	if tool.HTTPMethod == "" {
		tool.HTTPMethod = "GET"
	}
	if tool.AuthType == "" {
		tool.AuthType = model.ToolAuthTypeNone
	}

	status, body, err := executeCustomToolHTTP(ctx, s.httpClient, tool, req.Params)
	if err != nil {
		return nil, err
	}
	if len(body) > 500 {
		body = body[:500]
	}
	return &TestToolResult{Status: status, Body: body}, nil
}

func executeCustomToolHTTP(ctx context.Context, client HTTPDoer, tool *model.CaptainCustomTool, params map[string]interface{}) (int, string, error) {
	requestBody, err := buildRequestBody(tool.RequestTemplate, params)
	if err != nil {
		return 0, "", fmt.Errorf("build request body: %w", err)
	}

	method := strings.ToUpper(tool.HTTPMethod)
	var httpReq *http.Request
	if method == "GET" || method == "DELETE" {
		httpReq, err = http.NewRequestWithContext(ctx, method, tool.EndpointURL, nil)
	} else {
		httpReq, err = http.NewRequestWithContext(ctx, method, tool.EndpointURL, bytes.NewReader(requestBody))
	}
	if err != nil {
		return 0, "", fmt.Errorf("create HTTP request: %w", err)
	}
	if method != "GET" && method != "DELETE" {
		httpReq.Header.Set("Content-Type", "application/json")
	}
	if err := applyAuth(httpReq, tool); err != nil {
		return 0, "", fmt.Errorf("apply auth: %w", err)
	}

	resp, err := client.Do(httpReq)
	if err != nil {
		return 0, "", err
	}
	defer resp.Body.Close()

	respBody, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20))
	if err != nil {
		return 0, "", fmt.Errorf("read response: %w", err)
	}
	return resp.StatusCode, string(respBody), nil
}