package main

import (
	"errors"
	"flag"
	"fmt"
	"io/fs"
	"os"
	"path/filepath"
	"time"

	"github.com/peterbourgon/ff/v3"
)

var (
	resultmap = map[string]string{
		"y": "✔",
		"n": "✘",
		"a": "◒",
		"u": "‽",
		"i": "ⓘ",
		"w": "⚠",
	}
	supernums = "⁰¹²³⁴⁵⁶⁷⁸⁹"
	refresh   = time.Hour * 24 * 30
)

func main() {
	fs := flag.NewFlagSet("caniuse", flag.ContinueOnError)

	if err := ff.Parse(fs, os.Args[1:],
		ff.WithEnvVarPrefix("CANIUSE"),
	); err != nil {
		panic(err)
	}

	if fs.NArg() != 1 {
		fmt.Println("caniuse requires one argument")
		return
	}

	data, err := loadData()
	if err != nil {
		fmt.Printf("could not load data: %v", err)
	}

	fmt.Println(data)
}

func loadData() (Data, error) {
	var data Data

	cache, err := os.UserCacheDir()
	if err != nil {
		return data, fmt.Errorf("could not determine cache dir: %v", err)
	}

	caniuseCache := filepath.Join(cache, "caniuse")
	if err := os.MkdirAll(caniuseCache, os.ModePerm); err != nil {
		return data, fmt.Errorf("could not create dir %q: %v", caniuseCache, err)
	}

	dataPath := filepath.Join(caniuseCache, "data.json")
	fi, err := os.Stat(dataPath)
	if err != nil && !errors.Is(err, fs.ErrNotExist) {
		return data, fmt.Errorf("could not stat %q: %v", dataPath, err)
	} else if errors.Is(err, fs.ErrNotExist) || time.Since(fi.ModTime()) > refresh {
		if err := Download(dataPath); err != nil {
			return data, fmt.Errorf("could not download data: %v", err)
		}
	}

	return Load(dataPath)
}