package matrixbotlib

import (
	"errors"
	"os"

	"github.com/kelseyhightower/envconfig"
	"gopkg.in/yaml.v2"
)

// MatrixClientConfig represents the config requires to log into the matrix server
type MatrixClientConfig struct {
	Homeserver string `required:"true" yaml:"homeserver"`
	Domain     string `required:"true" yaml:"domain"`
	Dimension  string `yaml:"dimension"`
	Username   string `required:"true" yaml:"username"`
	Password   string `required:"true" yaml:"password"`
	Statefile  string `yaml:"statefile,omitempty"`
	Token      string `yaml:"token"`
	filename   string
}

// LoadMatrixClientConfig reads info from a file
func LoadMatrixClientConfig(filename string) (*MatrixClientConfig, error) {
	cnf := MatrixClientConfig{}
	if filename != "" {
		yamlFile, err := os.ReadFile(filename)
		if err == nil {
			err = yaml.Unmarshal(yamlFile, &cnf)
		} else {
			return &cnf, err
		}
		if err != nil {
			return &cnf, err
		}
		cnf.filename = filename
	} else {
		err := envconfig.Process("matrix", &cnf)
		if err != nil {
			return nil, err
		}
	}
	return &cnf, nil
}

// WriteMatrixClientConfig saves current running config to a file
func WriteMatrixClientConfig(cnf *MatrixClientConfig) error {
	if cnf.filename == "" {
		return errors.New("not loaded from config file")
	}
	file, err := os.OpenFile(cnf.filename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0o600)
	if err != nil {
		return err
	}
	defer file.Close()

	enc := yaml.NewEncoder(file)

	err = enc.Encode(cnf)
	if err != nil {
		return err
	}
	return nil
}