package idp

import (
	"encoding/json"
	"math/rand"
	"strings"
)

var (
	lowerCharSet   = "abcdedfghijklmnopqrst"
	upperCharSet   = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
	specialCharSet = "!@#$%&*"
	numberSet      = "0123456789"
	allCharSet     = lowerCharSet + upperCharSet + specialCharSet + numberSet
)

type JsonParser struct{}

func (JsonParser) Marshal(v interface{}) ([]byte, error) {
	return json.Marshal(v)
}

func (JsonParser) Unmarshal(data []byte, v interface{}) error {
	return json.Unmarshal(data, v)
}

// GeneratePassword generates user password
func GeneratePassword(passwordLength, minSpecialChar, minNum, minUpperCase int) string {
	var password strings.Builder

	//Set special character
	for i := 0; i < minSpecialChar; i++ {
		random := rand.Intn(len(specialCharSet))
		password.WriteString(string(specialCharSet[random]))
	}

	//Set numeric
	for i := 0; i < minNum; i++ {
		random := rand.Intn(len(numberSet))
		password.WriteString(string(numberSet[random]))
	}

	//Set uppercase
	for i := 0; i < minUpperCase; i++ {
		random := rand.Intn(len(upperCharSet))
		password.WriteString(string(upperCharSet[random]))
	}

	remainingLength := passwordLength - minSpecialChar - minNum - minUpperCase
	for i := 0; i < remainingLength; i++ {
		random := rand.Intn(len(allCharSet))
		password.WriteString(string(allCharSet[random]))
	}
	inRune := []rune(password.String())
	rand.Shuffle(len(inRune), func(i, j int) {
		inRune[i], inRune[j] = inRune[j], inRune[i]
	})
	return string(inRune)
}