// Homework 33, challenge: A calculator.
//
// Write a form with method "get" and action "/calc", with text inputs a and b,
// and a <select> named op with the options add, sub, mul and div. Then write
// handleCalc, which replies with text like "6 div 3 = 2".
//
// These all reply with status 400 and a useful message: a or b is not a whole
// number, a or b is not from -1000000 to 1000000, op is not one of the four,
// and div by 0.
//
// Think about why this form uses GET and not POST.
//
// Run with: go run exercises/33/homework/04-calculator.go

package main

import (
	"fmt"
	"net/http"
)

// TODO: add a constant holding the form page, and a handleForm for GET /{$}.

func handleCalc(w http.ResponseWriter, r *http.Request) {
	// TODO: write your code here, in place of this placeholder line:
	fmt.Fprintln(w, "TODO: replace this line")
}

func main() {
	http.HandleFunc("GET /calc", handleCalc)

	fmt.Println("Server running at http://localhost:8080")
	fmt.Println("Press Ctrl+C to stop it.")

	err := http.ListenAndServe("localhost:8080", nil)
	if err != nil {
		fmt.Println("Server stopped:", err)
	}
}