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package main

import "fmt"

type server interface {
	handleRequest(string, string) (int, string)
}

type nginx struct {
	appServer         *appServer
	maxAllowedRequest int
	rateLimiter       map[string]int
}

func newNginxServer() *nginx {
	return &nginx{
		appServer:         &appServer{},
		maxAllowedRequest: 2,
		rateLimiter:       make(map[string]int),
	}
}

func (n *nginx) handleRequest(url, method string) (int, string) {
	allowed := n.checkRateLimiting(url)
	if !allowed {
		return 403, "Not Allowed"
	}
	return n.appServer.handleRequest(url, method)
}

func (n *nginx) checkRateLimiting(url string) bool {
	if n.rateLimiter[url] == 0 {
		n.rateLimiter[url] = 1
	}
	if n.rateLimiter[url] > n.maxAllowedRequest {
		return false
	}
	n.rateLimiter[url] = n.rateLimiter[url] + 1
	return true
}

type appServer struct{}

func (a *applServer) handleRequest(url, method string) (int, string) {
	if url == "/app/status" && method == "GET" {
		return 200, "Ok"
	}
	if url == "/create/user" && method == "POST" {
		return 201, "User Created"
	}
	return 404, "Not Ok"
}

func main() {
	nginxServer := newNginxServer()
	appStatusURL := "/app/status"
	createuserURL := "/create/user"

	for i := 0; i <= nginxServer.maxAllowedRequest; i++ {
		httpCode, body := nginxServer.handleRequest(appStatusURL, "GET")
		fmt.Printf("\nUrl: %s\nHttpCode: %d\nBody: %s\n", appStatusURL, httpCode, body)
	}

	httpCode, body := nginxServer.handleRequest(createuserURL, "POST")
	fmt.Printf("\nUrl: %s\nHttpCode: %d\nBody: %s\n", createuserURL, httpCode, body)

	httpCode, body = nginxServer.handleRequest(createuserURL, "GET")
	fmt.Printf("\nUrl: %s\nHttpCode: %d\nBody: %s\n", createuserURL, httpCode, body)
}