package mydict

import "errors"

// Dictionary type
type Dictionary map[string]string

var (
	errNotFound   = errors.New("Not Found")
	errCantUpdate = errors.New("Cant update non-existing word")
	errWordExists = errors.New("That word  already exists")
)

// Search for a word
func (d Dictionary) Search(word string) (string, error) {
	value, exists := d[word]
	if exists {
		return value, nil
	}
	return "", errNotFound
}

// Add a word to the dictionary
func (d Dictionary) Add(word, def string) error {
	_, err := d.Search(word)
	switch err {
	case errNotFound:
		d[word] = def
	case nil:
		return errWordExists
	}

	return nil
}

// Update a word
func (d Dictionary) Update(word, definition string) error {
	_, err := d.Search(word)
	switch err {
	case nil:
		d[word] = definition
	case errNotFound:
		return errCantUpdate
	}
	return nil
}

// Delete a word
func (d Dictionary) Delete(word string) {
	delete(d, word)
}

package main

import (
	"fmt"

	"github.com/y00913/learngo/mydict"
)

func main() {
	dictionary := mydict.Dictionary{"first": "First word"}
	baseWord := "hello"
	dictionary.Add(baseWord, "First")
	dictionary.Search(baseWord)
	dictionary.Delete(baseWord)
	word, err := dictionary.Search(baseWord)
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Println(word)
	}
}