package config

import (
	"io/ioutil"

	"gopkg.in/yaml.v2"
)

type Config struct {
	Homeserver homeserver `yaml:"homeserver"`
	Appservice appservice `yaml:"appservice"`
	Bridge     bridge     `yaml:"bridge"`
	Logging    logging    `yaml:"logging"`
}

func (cfg *Config) validate() error {
	if err := cfg.Homeserver.validate(); err != nil {
		return err
	}

	if err := cfg.Appservice.validate(); err != nil {
		return err
	}

	if err := cfg.Bridge.validate(); err != nil {
		return err
	}

	if err := cfg.Logging.validate(); err != nil {
		return err
	}

	return nil
}

func (cfg *Config) UnmarshalYAML(unmarshal func(interface{}) error) error {
	type rawConfig Config

	raw := rawConfig{}
	if err := unmarshal(&raw); err != nil {
		return err
	}

	*cfg = Config(raw)

	return cfg.validate()
}

func FromBytes(data []byte) (*Config, error) {
	cfg := Config{}

	if err := yaml.Unmarshal(data, &cfg); err != nil {
		return nil, err
	}

	if err := cfg.validate(); err != nil {
		return nil, err
	}

	return &cfg, nil
}

func FromString(str string) (*Config, error) {
	return FromBytes([]byte(str))
}

func FromFile(filename string) (*Config, error) {
	data, err := ioutil.ReadFile(filename)
	if err != nil {
		return nil, err
	}

	return FromBytes(data)
}

func (cfg *Config) Save(filename string) error {
	data, err := yaml.Marshal(cfg)
	if err != nil {
		return err
	}

	return ioutil.WriteFile(filename, data, 0600)
}