package main

import (
	"encoding/json"
	"html/template"
	"log"
	"net/http"
)

type todo struct {
	UserID    int    `json:"userId"`
	ID        int    `json:"id"`
	Title     string `json:"title"`
	Completed bool   `json:"completed"`
}

var form = `
<h2>Todo #{{.ID}}</h2>
<div>{{printf "User %d" .UserID}}</div>
<div>{{printf "%s (status: %t)" .Title .Completed}}</div>
	`

func handler(w http.ResponseWriter, r *http.Request) {
	const base = "https://jsonplaceholder.typicode.com/"
	resp, err := http.Get(base + r.URL.Path[1:])
	if err != nil {
		http.Error(w, err.Error(), http.StatusServiceUnavailable)
		return
	}

	defer resp.Body.Close()

	var item todo

	if err = json.NewDecoder(resp.Body).Decode(&item); err != nil {
		http.Error(w, err.Error(), http.StatusServiceUnavailable)
		return
	}
	tmpl, err := template.New("Mine").Parse(form)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	if err := tmpl.Execute(w, item); err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
}

func main() {
	http.HandleFunc("/", handler)
	log.Fatal(http.ListenAndServe(":9090", nil))
}