feat: Added countries module

pkg/countries/constants.go

@@ -0,0 +1,10 @@
+package countries
+
+const flagImageUrl string = "https://flagcdn.com/w320/"
+const flagImageFormat string = ".png"
+const maxVariantsCount = 6
+const minVariantsCount = 2
+
+// error constants
+const variantsCountToBig string = "the number of variants is too large"
+const variantsCountToLow string = "the number of variants is too small"

pkg/countries/core.go

@@ -0,0 +1,49 @@
+package countries
+
+import (
+	"encoding/json"
+	"errors"
+	"io/ioutil"
+	"log"
+	"path/filepath"
+)
+
+var countriesDB []CountryData
+
+func init() {
+	countriesJson, err := ioutil.ReadFile(filepath.Join("data", "countries.json"))
+	if err != nil {
+		log.Printf("error opening file: %v \n", err)
+	}
+
+	err = json.Unmarshal((countriesJson), &countriesDB)
+	if err != nil {
+		log.Printf("error parsing JSON: %v \n", err)
+	}
+}
+
+func GetCapitalQuiz(variants int) (CapitalQuiz, error) {
+	if variants > maxVariantsCount {
+		return CapitalQuiz{}, errors.New(variantsCountToBig)
+	}
+
+	if variants < minVariantsCount {
+		return CapitalQuiz{}, errors.New(variantsCountToLow)
+	}
+
+	result := generateCapitalQuiz(variants)
+	return result, nil
+}
+
+func GetCountryQuiz(variants int) (CountryQuiz, error) {
+	if variants > maxVariantsCount {
+		return CountryQuiz{}, errors.New(variantsCountToBig)
+	}
+
+	if variants < minVariantsCount {
+		return CountryQuiz{}, errors.New(variantsCountToLow)
+	}
+
+	result := generateCountryQuiz(variants)
+	return result, nil
+}

pkg/countries/generator.go

@@ -0,0 +1,63 @@
+package countries
+
+import (
+	"math/rand"
+	"strings"
+
+	"github.com/cheatsnake/shadify/pkg/assists"
+)
+
+func generateCapitalQuiz(variantsCount int) CapitalQuiz {
+	variants := make([]string, variantsCount)
+	randomCountryIdx := rand.Intn(len(countriesDB))
+	randomCountry := countriesDB[randomCountryIdx]
+	flag := flagImageUrl + strings.ToLower(randomCountry.Code) + flagImageFormat
+	variants[0] = randomCountry.Capital
+
+	for i := 1; i < variantsCount; i += 0 {
+		randomIdx := rand.Intn(len(countriesDB))
+		capital := countriesDB[randomIdx].Capital
+
+		if assists.IndexOf(capital, variants) == -1 {
+			variants[i] = countriesDB[randomIdx].Capital
+			i++
+		}
+	}
+
+	rand.Shuffle(len(variants), func(i, j int) {
+		variants[i], variants[j] = variants[j], variants[i]
+	})
+
+	return CapitalQuiz{
+		Country:  randomCountry.Country,
+		Flag:     flag,
+		Variants: variants,
+		Answer:   randomCountry.Capital}
+}
+
+func generateCountryQuiz(variantsCount int) CountryQuiz {
+	variants := make([]string, variantsCount)
+	randomCountryIdx := rand.Intn(len(countriesDB))
+	randomCountry := countriesDB[randomCountryIdx]
+	flag := flagImageUrl + strings.ToLower(randomCountry.Code) + flagImageFormat
+	variants[0] = randomCountry.Country
+
+	for i := 1; i < variantsCount; i += 0 {
+		randomIdx := rand.Intn(len(countriesDB))
+		country := countriesDB[randomIdx].Country
+
+		if assists.IndexOf(country, variants) == -1 {
+			variants[i] = countriesDB[randomIdx].Country
+			i++
+		}
+	}
+
+	rand.Shuffle(len(variants), func(i, j int) {
+		variants[i], variants[j] = variants[j], variants[i]
+	})
+
+	return CountryQuiz{
+		Flag:     flag,
+		Variants: variants,
+		Answer:   randomCountry.Country}
+}

pkg/countries/types.go

@@ -0,0 +1,20 @@
+package countries
+
+type CountryData struct {
+	Code    string `json:"code"`
+	Country string `json:"country"`
+	Capital string `json:"capital"`
+}
+
+type CountryQuiz struct {
+	Flag     string   `json:"flag"`
+	Variants []string `json:"variants"`
+	Answer   string   `json:"answer"`
+}
+
+type CapitalQuiz struct {
+	Country  string   `json:"country"`
+	Flag     string   `json:"flag"`
+	Variants []string `json:"variants"`
+	Answer   string   `json:"answer"`
+}