weather/main.go

package main

import (
	"context"
	"fmt"
	"os"
	"time"
)

const (
	defaultForecastTTL = 10 * time.Minute
)

func main() {
	if err := run(); err != nil {
		fmt.Fprintln(os.Stderr, err.Error())
		os.Exit(1)
	}
}

func run() error {
	opts, err := parseArgs(os.Args[1:])
	if err != nil {
		return err
	}

	ua, err := buildUserAgent()
	if err != nil {
		return err
	}

	cacheDir, err := cacheRoot()
	if err != nil {
		return err
	}

	cache := NewCache(cacheDir)
	ctx := context.Background()

	if opts.iconTest {
		printIconTest()
		return nil
	}

	if opts.wayland && opts.searchSet {
		if err := requireRofi(); err != nil {
			return err
		}
	}

	if opts.radarMode {
		if err := requireMPV(); err != nil {
			return err
		}
	}

	if opts.clearCache {
		if err := cache.Clear(); err != nil {
			return err
		}
		return nil
	}

	var loc Location
	if opts.wayland && opts.searchSet {
		if opts.searchValue == "" {
			var err error
			loc, err = interactiveSearch(ctx, cache, ua)
			if err != nil {
				return err
			}
		} else {
			var err error
			loc, err = interactiveSearch(ctx, cache, ua)
			if err != nil {
				return err
			}
		}
	} else if opts.searchSet {
		if opts.searchValue == "" {
			return fmt.Errorf("--search requires a value unless --wayland is set")
		}
		results, err := SearchLocations(ctx, opts.searchValue, ua)
		if err != nil {
			return err
		}
		loc, err = SelectLocation(results)
		if err != nil {
			return err
		}
		if err := cache.SaveLocation(opts.searchValue, loc); err != nil {
			return err
		}
	} else {
		var ok bool
		loc, ok, err = cache.LoadLocation()
		if err != nil {
			return err
		}
		if !ok {
			return fmt.Errorf("no cached location found; use -s to set a location")
		}
	}

	if opts.radarMode {
		return runRadar(ctx, cache, loc, opts.searchValue, ua)
	}
	if opts.discussion {
		text, err := runDiscussion(ctx, cache, loc, opts.searchValue, ua)
		if err != nil {
			return err
		}
		if opts.wayland {
			return runDiscussionWayland(ctx, formatAFDMarkdown(text))
		}
		fmt.Println(text)
		return nil
	}

	client := NewNWSClient(ua)
	var period ForecastPeriod
	if opts.refresh {
		var err error
		period, err = client.FetchForecast(ctx, loc, opts.temperatureU)
		if err != nil {
			return err
		}
		if err := cache.SaveForecast(loc, opts.temperatureU, period); err != nil {
			return err
		}
	} else {
		var err error
		var fromCache bool
		period, fromCache, err = cache.LoadForecast(loc, opts.temperatureU, defaultForecastTTL)
		if err != nil {
			return err
		}
		if !fromCache {
			period, err = client.FetchForecast(ctx, loc, opts.temperatureU)
			if err != nil {
				return err
			}
			if err := cache.SaveForecast(loc, opts.temperatureU, period); err != nil {
				return err
			}
		}
	}

	line := FormatOutput(loc, period, opts.includeDesc, opts.prettyOutput)
	fmt.Println(line)
	return nil
}