moonmath/moonmath.go

package main

import (
	"fmt"
	"io"
	"log/slog"
	"os"
	"path/filepath"
	"strings"

	"code.humancabbage.net/sam/moonmath/coindesk"
	"code.humancabbage.net/sam/moonmath/config"
	"code.humancabbage.net/sam/moonmath/tui"
	"github.com/alecthomas/kong"
	tea "github.com/charmbracelet/bubbletea"
)

var CLI struct {
	Asset      []string `short:"a" default:"BTC" help:"Asset(s) to project."`
	ConfigFile string   `short:"c" help:"Path to YAML configuration file."`
	Perf       bool     `help:"Display internal performance stats."`
}

func main() {
	logFile := setupLogging()
	defer func() {
		_ = logFile.Close()
	}()
	ctx := kong.Parse(&CLI)
	if ctx.Error != nil {
		fail(ctx.Error)
	}
	allCfg, err := config.Load(CLI.ConfigFile)
	if err != nil {
		fail(err)
	}
	var assets []coindesk.Asset
	for i := range CLI.Asset {
		asset := coindesk.Asset(strings.ToUpper(CLI.Asset[i]))
		assets = append(assets, asset)
	}
	m := tui.New(assets, allCfg, CLI.Perf)
	p := tea.NewProgram(m,
		tea.WithAltScreen(),
		tea.WithFPS(30),
	)
	if _, err := p.Run(); err != nil {
		fail(err)
	}
}

func setupLogging() io.Closer {
	homePath, err := os.UserHomeDir()
	if err != nil {
		panic(err)
	}

	programConfigPath := filepath.Join(homePath, ".moonmath")
	err = os.MkdirAll(programConfigPath, 0755)
	if err != nil {
		panic(err)
	}

	errLogPath := filepath.Join(programConfigPath, "errors.log")
	errLogFile, err := os.OpenFile(
		errLogPath,
		os.O_CREATE|os.O_APPEND|os.O_WRONLY,
		0600,
	)
	if err != nil {
		panic(err)
	}

	slog.SetDefault(slog.New(
		slog.NewTextHandler(errLogFile, &slog.HandlerOptions{
			Level: slog.LevelError,
		})))
	return errLogFile
}

func fail(err error) {
	fmt.Printf("program error: %v\n", err)
	os.Exit(1)
}