package main

import (
	"fmt"
	"os"

	"gopkg.in/yaml.v2"
)

type YamlVersionProvider struct {
	File string
	Key  string
}

type YamlVersion string

func (y YamlVersion) String() string { return string(y) }

func (y YamlVersionProvider) GetVersion() (Version, error) {
	f, err := os.Open(y.File)
	if err != nil {
		return nil, fmt.Errorf("couldn't open yaml file for reading: %w", err)
	}
	defer f.Close()
	var data map[string]interface{}
	err = yaml.NewDecoder(f).Decode(&data)
	if err != nil {
		return nil, fmt.Errorf("couldn't parse yaml file: %w", err)
	}

	val, ok := data[y.Key]
	if !ok {
		return nil, fmt.Errorf("couldn't find key \"%s\"", y.Key)
	}

	return YamlVersion(fmt.Sprintf("%v", val)), nil
}