/*
 * File: Validator.cpp
 * Description: Validates inputs like phone number, email, password
 * Author: Trenser
 * Created: 18-May-2026
 */

#include <string>
#include <cctype>
#include "Validator.h"

 /*
  * Function: isPhoneNumberValid
  * Description: Validates whether the given string is a valid phone number.
  * Parameters:
  *     phoneNumber - string containing the phone number to validate
  * Returns:
  *     bool - true if the phone number is valid (10 digits, all numeric), false otherwise
  */
bool util::isPhoneNumberValid(const std::string& phoneNumber)
{
    if (phoneNumber.size() != 10)
    {
        return false;
    }
    return std::all_of(phoneNumber.begin(), phoneNumber.end(),
        [](char character)
        {
            return std::isdigit(character);
        }
    );
}

/*
 * Function: isEmailValid
 * Description: Validates whether the given string is a properly formatted email address.
 * Parameters:
 *     email - string containing the email address to validate
 * Returns:
 *     bool - true if the email contains exactly one '@' character and is not at the start or end, false otherwise
 */
bool util::isEmailValid(const std::string& email)
{
    size_t index = email.find('@');
    if (index == std::string::npos)
    {
        return false;
    }
    if (email.find('@', index + 1) != std::string::npos)
    {
        return false;
    }
    if (index == 0 || index == email.size() - 1)
    {
        return false;
    }
    return true;
}

/*
 * Function: isPasswordValid
 * Description: Validates whether the given string meets password requirements.
 * Parameters:
 *     password - string containing the password to validate
 * Returns:
 *     bool - true if the password is valid, false otherwise
 * Notes:
 *     - Must not equal the default password
 *     - Must be at least 8 characters long
 *     - Must contain at least one uppercase letter, one lowercase letter,
 *       one digit, and one special character
 *     - Must not contain whitespace
 */
bool util::isPasswordValid(const std::string& password)
{
    if (password.length() < 8)
    {
        return false;
    }
    bool hasUpper = false;
    bool hasLower = false;
    bool hasDigit = false;
    bool hasSpecial = false;
    for (char character : password)
    {
        if (std::isspace(static_cast<unsigned char>(character)))
        {
            return false;
        }
        if (std::isupper(static_cast<unsigned char>(character)))
        {
            hasUpper = true;
        }
        else if (std::islower(static_cast<unsigned char>(character)))
        {
            hasLower = true;
        }
        else if (std::isdigit(static_cast<unsigned char>(character)))
        {
            hasDigit = true;
        }
        else
        {
            hasSpecial = true;
        }
    }

    return hasUpper && hasLower && hasDigit && hasSpecial;
}

/*
 * Function: isUsernameDuplicate
 * Description: Checks if the given username already exists among active users.
 * Parameters:
 *     username - string containing the username to validate
 *     usersMap - map of user objects keyed by identifier
 * Returns:
 *     bool - true if the username is already in use by an active user, false otherwise
 */
bool util::isUsernameDuplicate(const std::string& username, const util::Map<std::string, User*>& usersMap)
{
    int index = usersMap.findIf(
        [&](const std::string&, User* user)
        {
            return (user->getUserName() == username);
        }
    );
    return index != -1;
}

/*
 * Function: isPhoneDuplicate
 * Description: Checks if the given phone number already exists among active users.
 * Parameters:
 *     phone - string containing the phone number to validate
 *     usersMap - map of user objects keyed by identifier
 * Returns:
 *     bool - true if the phone number is already in use by an active user, false otherwise
 * Notes:
 *     - Only considers users with state util::State::ACTIVE
 */
bool util::isPhoneDuplicate(const std::string& phone, const util::Map<std::string, User*>& usersMap)
{
    int index = usersMap.findIf(
        [&](const std::string&, User* user)
        {
            return (user->getPhone() == phone && user->getState() == util::State::ACTIVE);
        }
    );
    return index != -1;
}

/*
 * Function: isEmailDuplicate
 * Description: Checks if the given email address already exists among active users.
 * Parameters:
 *     email - string containing the email address to validate
 *     usersMap - map of user objects keyed by identifier
 * Returns:
 *     bool - true if the email address is already in use by an active user, false otherwise
 * Notes:
 *     - Only considers users with state util::State::ACTIVE
 */
bool util::isEmailDuplicate(const std::string& email, const util::Map<std::string, User*>& usersMap)
{
    int index = usersMap.findIf(
        [&](const std::string&, User* user)
        {
            return (user->getEmail() == email && user->getState() == util::State::ACTIVE);
        }
    );
    return index != -1;
}