//
//  CommFunc.swift
//  AIGrammar
//
//  Created by oscar on 2024/8/5.
//

import Foundation

class CommonFunc {
    static let shared = CommonFunc()
    private let profanityList: [String] = ["fuck", "shit", "porn", "习近平", "鸡巴", "阴茎"] // Example profanity words

    private init() {} // Private initializer to ensure singleton usage

    func validateInputEng(input: String, isSingleWord: Bool = false) -> (isValid: Bool, message: String) {
        // Check for profanity
        for badWord in profanityList {
            if input.lowercased().contains(badWord) {
                return (false, globalEnvironment.DirtyInputErrToast)
            }
        }
        
        // Check characters based on the isSingleWord flag
        let pattern = isSingleWord ? "^[A-Za-z]+$" : "^[A-Za-z0-9 .,;:!?'\"@-]+$"
        let regex = try! NSRegularExpression(pattern: pattern)
        let range = NSRange(location: 0, length: input.utf16.count)

        if regex.firstMatch(in: input, options: [], range: range) == nil {
            let characterSet = isSingleWord ? "english letters" : "english letters, numbers, and punctuation"
            return (false, "Input should only contain \(characterSet).")
        }
        
        return (true, "Input is valid.")
    }
    
    func validateChineseInput(input: String) -> (isValid: Bool, message: String) {
        // Check for profanity
        for word in profanityList {
            if input.contains(word) {
                return (false, globalEnvironment.DirtyInputErrToast)
            }
        }

        // Check if all characters are valid Chinese characters or punctuation
        for character in input {
            if !character.isPunctuation && !(0x4E00...0x9FFF).contains(character.unicodeScalars.first!.value) &&
                !(0x3400...0x4DBF).contains(character.unicodeScalars.first!.value) &&
                !(0x20000...0x2A6DF).contains(character.unicodeScalars.first!.value) {
                // 既不是中文，又不是英文，返回错误
                let res = self.validateInputEng(input: input)
                if !res.isValid{
                    return (false, "Input contains invalid characters.")
                }
            }
        }
        return (true, "Input is valid.")
    }
        
}