package config

import (
	"errors"
	"fmt"
	"os"
	"path/filepath"

	"github.com/pelletier/go-toml/v2"
)

type Config struct {
	JournalDir string `toml:"journal_dir"`
}

func Default() (Config, error) {
	home, err := os.UserHomeDir()
	if err != nil {
		return Config{}, fmt.Errorf("cannot determine home dir: %w", err)
	}
	return Config{
		JournalDir: filepath.Join(home, "journal"),
	}, nil
}

func Path() (string, error) {
	cd, err := os.UserConfigDir()
	if err != nil {
		return "", fmt.Errorf("could not determine user config dir: %w", err)
	}
	configPath := filepath.Join(cd, "journal.toml")
	return configPath, nil
}

func LoadOrCreate() (Config, bool, error) {

	configPath, err := Path()
	if err != nil {
		return Config{}, false, fmt.Errorf("could not determine user config dir: %w", err)
	}

	f, err := os.Open(configPath)

	if err != nil && !errors.Is(err, os.ErrNotExist) {
		fmt.Printf("\n\nerr: %v %T\n\n", err, err)
		return Config{}, false, fmt.Errorf("could not open user config '%s': %w", configPath, err)
	} else if err != nil { // not exist
		f, err = os.Create(configPath)
		if err != nil {
			return Config{}, false, fmt.Errorf("could not create user config '%s': %w", configPath, err)
		}
		def, err := Default()
		if err != nil {
			return Config{}, false, fmt.Errorf("could not generate default config: %w", err)
		}

		err = toml.NewEncoder(f).Encode(def)
		if err != nil {
			return Config{}, false, fmt.Errorf("could not encode new config: %w", err)
		}

		err = f.Close()
		if err != nil {
			return Config{}, false, fmt.Errorf("could not close file: %w", err)
		}

		return def, true, createJournalDirIfNecessary(def)
	} else {
		config := Config{}
		err = toml.NewDecoder(f).Decode(&config)
		if err != nil {
			return Config{}, false, fmt.Errorf("could not decode config in '%s': %w", configPath, err)
		}
		err = f.Close()
		if err != nil {
			return Config{}, false, fmt.Errorf("could not close file: %w", err)
		}
		return config, false, createJournalDirIfNecessary(config)
	}
}

func createJournalDirIfNecessary(c Config) error {
	err := os.Mkdir(c.JournalDir, 0777)
	if err != nil && errors.Is(err, os.ErrExist) {
		return nil
	} else if err != nil {
		return err
	}
	return nil
}